Introduction to Valves (Mechanical Engineering and Oil and Gas) | SaVRee 3D | Skillshare

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Introduction to Valves (Mechanical Engineering and Oil and Gas)

teacher avatar SaVRee 3D, Where engineers go to learn.

Watch this class and thousands more

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Taught by industry leaders & working professionals
Topics include illustration, design, photography, and more

Watch this class and thousands more

Get unlimited access to every class
Taught by industry leaders & working professionals
Topics include illustration, design, photography, and more

Lessons in This Class

100 Lessons (4h 23m)
    • 1. 00 Course Overview

    • 2. 01 Welcome To The Course

    • 3. 02 Short Introduction to Valves

    • 4. 03 How Do Valves Get Their Names?

    • 5. 04 Introduction to Valve Types

    • 6. 05 Purpose of a Valve and Construction

    • 7. 06 Rotary and Linear Motion Valves

    • 8. 07 Valve Construction and Components

    • 9. 08 Valve Actuators

    • 10. 09 Pressure Drop

    • 11. 10 Response Time

    • 12. 11 Length of Travel

    • 13. 12 Ball Valves

    • 14. 13 Butterfly Valves

    • 15. 14 Diaphragm Valves

    • 16. 15 Gate Valves

    • 17. 16 Pinch Valves

    • 18. 17 Plug Valves

    • 19. 18 Basic Course Final Thoughts

    • 20. 19 Welcome To The Advanced Course

    • 21. 20 Valve Body

    • 22. 21 Valve Bonnet

    • 23. 22 Valve Trim

    • 24. 23 Valve Disc and Seat

    • 25. 24 Valve Stem

    • 26. 25 Valve Actuator

    • 27. 26 Valve Packing

    • 28. 27 Valve Functions and Basic Parts Summary

    • 29. 28 Introduction to Valve Actuators

    • 30. 29 Valve Actuators

    • 31. 30 Manual, Fixed, and Hammer Actuators

    • 32. 31 Handwheels Fixed to Stem

    • 33. 32 Hammer Handwheel

    • 34. 33 Gears

    • 35. 34 Electric Motor Actuators

    • 36. 35 Pneumatic Actuators

    • 37. 36 Hydraulic Actuators

    • 38. 37 Self Actuated Valves

    • 39. 38 Solenoid Actuated Valves

    • 40. 39 Speed of Power Actuators

    • 41. 40 Valve Position Indication

    • 42. 41 Valve Actuators Summary

    • 43. 42 Gate Valves

    • 44. 43 Gate Valve Disk Design

    • 45. 44 Solid Wedge

    • 46. 45 Flexible Wedge

    • 47. 46 Split Wedge

    • 48. 47 Parallel Wedge

    • 49. 48 Gate Valve Stem Design

    • 50. 49 Gate Valve Seat Design

    • 51. 50 Globe Valves

    • 52. 51 Globe Valve Body Designs

    • 53. 52 Z Body Design

    • 54. 53 Y Body Design

    • 55. 54 Angle Valve Design

    • 56. 55 Globe Valve Discs

    • 57. 56 Ball Disc

    • 58. 57 Composition Disc

    • 59. 58 Plug Disc

    • 60. 59 Globe Valve Disc and Stem Connections

    • 61. 60 Globe Valve Seats

    • 62. 61 Globe Valve Direction of Flow

    • 63. 62 Ball Valves

    • 64. 63 Ball Valve Advantages

    • 65. 64 Ball Valve Disadvantages

    • 66. 65 Ball Valve Port Patterns

    • 67. 66 Ball Valve Materials

    • 68. 67 Ball Valve Stem Design

    • 69. 68 Ball Valve Bonnet Design

    • 70. 69 Ball Valve Position

    • 71. 70 Plug Valves

    • 72. 71 Plug Ports

    • 73. 72 Multiport Plug Valves

    • 74. 73 Plug Valve Disks

    • 75. 74 Diamond Port Plug

    • 76. 75 Lubricated Plug Valve Design

    • 77. 76 Non Lubricated Plugs

    • 78. 77 Manually Operated Plug Valve Installation

    • 79. 78 Plug Valve Glands

    • 80. 79 Diaphragm Valves

    • 81. 80 Diaphragm Construction

    • 82. 81 Diaphragm Valve Stem Assemblies

    • 83. 82 Diaphragm Valve Bonnet Assemblies

    • 84. 83 Reducing Valves

    • 85. 84 Pinch Valves

    • 86. 85 Pinch Valve Bodies

    • 87. 86 Butterfly Valves

    • 88. 87 Butterfly Valve Seat Construction

    • 89. 88 Butterfly Valve Body Construction

    • 90. 89 Butterfly Valve Disk and Stem Assemblies

    • 91. 90 Needle Valves

    • 92. 91 Needle Valve Applications

    • 93. 92 Needle Valve Body Designs

    • 94. 93 Check Valves

    • 95. 94 Swing Check Valves

    • 96. 95 Relief and Safety Valves

    • 97. 96 Pilot Operated Relief Valves

    • 98. 97 Types of Valves Summary

    • 99. 98 Final Thoughts

    • 100. 99 Bonus Video - Pneumatic Actuated Globe Valve

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About This Class

Learn about valve construction, design and application. Discover the ball, butterfly, diaphragm, gate, globe and plug valves...and many more valve types!

Ever wondered:

  • Why do we need so many different valve types?

  • What kind of valve is correct for x,y,z application?

  • What are the pros and cons of each valve type?

  • Why do valves have weird names i.e. butterfly valve?

This course will help you answer these questions...and many more!

The course is designed to take you from zero to hero concerning valve knowledge. Even if you already have some background knowledge, this course will serve as an efficient refresher. Whatever your level of understanding or engineering background (oil, gas, marine, power etc.), I can guarantee you will have never taken an engineering course like this one.

Interactive 3D models are used extensively to show you exactly how valves and their components work.

The course is packed with 2D images, 2D animations and 3D animations.

Written content has been read aloud so that you can 'learn on the go' without needing to watch the screen constantly.

I hope to see you on the course!



This course is split into Basic and Advanced.


Meet Your Teacher

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SaVRee 3D Where engineers go to learn.


saVRee produces high quality video courses for the engineering market. Our courses are taught by subject matter experts (SMEs) with years of experience in many different industries.

If you are interested in HVAC, Mechanical, Electrical, Automobile, Chemical, Power or Industrial Engineering, we have courses for you!

Courses are presented using interactive 3D models and 3D animations. The 3D models can be exploded into their parts and a cross section feature allows you to see exactly what is happening inside the machine.

We also read written content aloud so that you can learn 'on-the-go'

If you are a professional engineer, or a student preparing for entry into the exciting world of engineering, we guarantee you will find our courses of great benefit.

Jo... See full profile

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1. 00 Course Overview: valves they used in every engineering industry on the planet. Whenever you want to start, stop or regulate flow within a process, you're going to need to use a valve. They're some of the most common components that you're ever likely to encounter when working in an engineering industry. But what about valves? Why do we have so many different types? How do you select the right valve for the right application? A. Wider Some valves have such weird names like the butterfly valve. Well, in this course, we're going to answer all of these questions and many, many more. By the time he finished his course, you're going to know all of the main components that make up a vow. You're going to be able to identify each valve type. You're going to know the advances and disadvantages associated with each type of our, and you're going to know which type of valve is suitable for which application. We're going to use interactive three D models throughout the entire course. You're going to see how each type of valve works you're going to see inside each type of valve, using a unique cross section feature. We're gonna hide in show parts so that you get a greater understanding of how valves components fit together in order for it to work. There are also two D images and high quality written text. This course is suitable for anyone who is working in an engineering industry or training to enter one. Even if you've been working in engineering industry for a long time, this course will serve as an efficient refresher. So check out some of the free preview videos, see if the content and teaching style agrees with you. And if it does, I hope so. You on the course. 2. 01 Welcome To The Course: Hi, John here. I just wanted to do a short video just to say thank you very much for purchasing this course. This is a welcome video of put in all of my courses, and it's just a way of saying thank you. I know there's a 1,000,001 other things that you could be doing with your time right now on the fact that you've taken time out on actually spent some money to purchases, course and invested time it takes to learn from it is really great and trauma say thanks. The other reason I want to say thank you is because your purchase helps me personally produce more more content on this is something that I really enjoy. I enjoy helping people learn. I enjoy teaching. A new perch in this course helps me continue. So without further ado, let's start the course. Its get stuck right in. I really hope you enjoy it. If you've got any feedback, please do let me know because this is really valuable. It helps me improve the course, the courses in static. I'm going to continue to improve it, change things on feedback is always, always welcome. 20 questions then, please, do you shoot them off to me? I'll answer them as quickly and thoroughly as I can. Great. Thanks very much for your time. 3. 02 Short Introduction to Valves: John here in this video, I'm going to explain to you how the blow gate ball plug, butterfly diaphragm check pinch and safety valves work. I'm also going to tell you about the different types of valve classification. How valves get their names, what vowels actually do. So let's start with the basics. How do we name a valve? Almost always. Valves get their name from the type of disc used. The disk is depart the valve that is used open, close or regulate the flow through the valve. Regulating the flow is referred to as throttling. What we're looking at now is a ball valve because of the ball like shape of the disc. The Butterfly valve, his name because of its similar appearance to a butterfly on the gate valve, is named because of its similar appearance to a gate. There are exceptions to the rule, though Globe valves are named after the shape of the valve body itself. That's a useful stopping and starting flow, varying the amount of flow control in the direction of float, regulating downstream system or process pressure, and finally, for relieving system over and under pressure vows could be categorized as rotary or linear motion valves. Rotary valves are those which require 1/4 of a turn in orders to change position from fully open to fully closed or vice versa. Rotary valves. Our fast acting valves. Examples of rotary valves would include the ball plug on butterfly house Lini. Emotion valves are slower to operate in court. To turn valves, linear motion vows raise or lower the disc in order to open, regulate or close the flow through the valve. Examples of linear motion valves includes the gate and globe site valves. There are four main types of actuators used to operate the valves. These are mechanical, electrical, hydraulic and pneumatic. A ball valve is a rotary motion valve that uses a ball shaped disc to stop or start float. When the valve handle is turned to open the valve, the ball rotates to a point where the whole threw. The ball is in line with the valve, body, inlet and outlet. When the valve is shot, the ball is rotated so that the whole is perpendicular to the flow. Opening of the valve body on the floor has stopped. Ball valves are not suitable for front wing or regulating flow the pressure drop across ball valves when fully open is very low. Small to medium sized ball valves. Our fast acting board to turn valves large. A ball valves. Employer. Planetary gearbox. The planetary gearbox allows the use of a relatively small hand wheel on operating force to operate a fairly large valve. A butterfly valve is a rotary motion valve that is used to stop regulate and start flow. Like all Quarter two involves. The butterfly valve is fast acting larger. Butterfly vows employed planetary type gearboxes. Butterfly vows possessed many advantages over gate globe. Plug on ball type valves, especially for larger applications. Savings in weight spaces costs of the most obvious advantages. The pressure drop across the butterfly valve when the valve is really open is low. But if I valves are very well suited for the handling of large flows of liquids or gases are relatively low pressures. A diaphragm valve is a linear motion type valve that is used to start regulate or stop fluid flow. A flexible diaphragm can be raised or lowered onto the valve seat in order to open or close the valve. A great advantage with the diaphragm type valve is that very few parts are exposed to the flowing medium. The valve is constructed so that only the flexible diaphragm on internal valve flow passages are exposed to the flowing medium. This makes it particularly well suited for the handling of corrosive fluids, fibrous Lorries, radioactive fluids or other fluids that must remain free from contamination. Gate valves. The most common type of vows employed today. Gate valves, Illini emotion type valve. Used to start or stop flow. It is not suitable for regulating flow. The main gate is derived from the appearance of the valve disk. The disc of the gate valve is completely removed from the flow upstream when the valve is fully open. This allows flow through the valve with virtually no resistance. This gives the valve at a very low pressure drop across the valve. The major of answers is with the gate valve of additives. Cheap has a simple design, and there is a very low pressure drop across the valve when it is fully open. The major disadvantages with gate valves, whether they are not suitable for frightening applications there are also prone to excessive vibration when only partially open compared to a globe valves they're more susceptible to see and disk wear on. Potential leaking globe valves is a linear motion valve used to stop, start and regulate fluid flow. There are four main glow Val designs. Straight flow angle flow, cross flow on Dwight flow compared to a gate valve, A globe valve generally yields much less see leakage. This is because the dis deceit ring contact is more right angles, which commits the force of closing too tightly. Seat the disc. Globe valves are almost always installed with the system pressure on the underside of the valve. See, this makes it easier to open. The valve on also removes the pressure on the stem packing on bonnet when the valve is closed. The largest disadvantage with a globe valve is that there is a relatively large pressure drop across the valve. In addition, large globe valve sizes require considerable power to operate on our especially noisy and high pressure applications. Globe valves are also often heavier than other type of vows with the same flow rating. Pinch valves are inexpensive and are the simplest of any valve design. The pinch control valve consists of a sleeve molded of rubber or other synthetic material on a pinching mechanism. Pinch valves could be used to start, stop or regulate flow. However, the effective throttling range is usually between 10% and 95% of the rate of flow capacity . There is almost no pressure drop across a pinch valve. Pinch valves are ideally suited for the handling of Slattery's with large amounts of suspended solids. This is because they have a very large seating area because the operating mechanisms off the valve are completely isolated from the floor. In medium, these valves are very well suited, where corrosion or metal contamination of the flow medium might be a problem. A flood valve is a rotary motion valve used to start or stop float. The name is derived from the shape of the disc, which resembles a plug. The design is very similar to a ball valve where the shape of the disk is different In the open position, the passage in the blood lines up with the inlet and outlet ports of the valve body. When the plug is turned 90 degrees from the open position, the solid part of plug block supports and stops float when the blood valve is fully open, there is a very low pressure drop across the valves. An important characteristic of the plug valve is that it is easy to adapt for multi port applications. The use of a multi port valve, depending upon the number of ports in the plug valve, eliminates the need of a Semenya's four conventional shut off valves. This is a considerable cost on space saving plug Vows are often used in non throttling on off applications, particularly where the valve must be operated frequently. Check valves are designed to prevent the reversal of flow in a piping system. These valves air activated by the float material in the pipeline. The pressure of the fluid passing through the system opens a valve. Whilst any reversal of flow will close, the valve closure is accomplished by the weight of the check mechanism. Buy back pressure by a spring or by any combination of these means. The most common type of check valves are the swing, tilting disk, piston, butterfly and stop valves. The type of check valve used will depend upon the system pressure, temperature and flow requirements. For example, swing check balls are very well suited for medium velocity. High volume flow applications. There is also a relatively low pressure drop across this type of valve. A needle valve is used to make relatively fine adjustments in the amount of fluid flow. The most distinguishing characteristic of a needle valve is the long, tapered, needle like point on the end of the valve stem. The needle acts as a disc. The longer part, the needle is smaller than the orifice in the Val see on passes through the orifice before the needle seats. This arrangement permits a very gradual increase or decrease in the size of the opening need allows. Frequently used as meeting valves. This is because the number of turns of the hand wheel could be directly correlated to the amount of float relief in safety. Vows prevent equipment damaged by relieving accidental system over pressurization. A relief valve gradually opens as the inlet pressure increases above the set point. The valve only opens enough to relieve the overpressure condition. Where is the safety valve? Rapidly pops fully open as soon as the pressure setting is reached and it will stay fully open until the pressure drops below a reset pressure solenoid valves, electro mechanically operated valves. They are very well suited to opening and closing operations. They can be used to start or stop flow, but are not well suited for regulating float. This type of valve is fast acting. An electro magnet is used to operate the valve when current is supplied to the wind ing's. The spring is used to return the valve to its fail safe position when the electrical current is no longer present. 4. 03 How Do Valves Get Their Names?: So let's start with the absolute basics here. How do valves get their names in the first place? Well, the simple answer is the valve is nine times out of 10. Named after the type of disc it uses on the disk Is this center component here? This is the bit that does the opening and closing and regulating of the valve on in this case at disc is, as the label says, a bull. So this is a all. And if we check out another design now, here is another valve design. It's the needle valve on the new valve has a disc shaped like a needle. It's just area. Here on a final example would be a gate valve. You can see this gate actually raises and lowers or is raised and lowered, and it's similar to a gate that they reduced at a castle. In other words, it drops down on it is raised up, and that is a gate type fouls. So that is nine times out of 10. How valves get their names. But there are exceptions. I'll show you one. Now we can see here that this type of valve, which is a globe valve does not have a disc of these spherical in shape or shaped like a globe. That is the disk here. Zoom in and it doesn't look like a globe whatsoever. It would be more called a flat pancake valves. But if we spin around, the valve body itself is slightly spherical on. This is the reason why the valve is called a globe valve. So although the rule is that the valve should be named after the disk, there are exceptions. And the glow vow is one of them, However, for the ball, Butterfly Needle on Diaphragm vows they are all named after the type of disc used. 5. 04 Introduction to Valve Types: introduction to valve types. Because of the diversity of the types of systems, fluids and environments in which violence must operate, a vast array of valve types have been developed. Examples of the common types are the globe valve, gate valve, ball valve, plug valve, butterfly valve, diaphragm valve check, 12 pinch 12 and safety valve. Each type of valve has been designed to meet specific needs. Some valves, a capable of throttling flow. Other valves types can only stop float. Others work well in corrosive systems. Another's handle high pressure fluids. Each valve type has certain inherent advantages and disadvantages. Understanding these differences in how they affect the valves, application or operation is necessary for the successful operation of a facility. Although vows have the same basic components and function to control flow in some fashion, the method of controlling the flow can vary dramatically. In general, there are four methods of controlling flow through a valve one movie discs or plug into or against an orifice, for example, global needle type valves to slide a flat, cylindrical or spherical surface across an orifice. For example, Gaitan plug valves, three rotating disc or lips about a shaft extending across the diameter of an orifice. For example, a butterfly or ball valve for move a flexible material into the flow passage. For example, diaphragm and pinch valves, each method of controlling flow as characteristics that make it the best choice for a given application of function. Due to various environments, system fluids and system conditions in which flow must be controlled, a large number of valve designs have been developed. Basic understanding of the differences between the various types of valves and how these differences affect valve function will help ensure the proper application of each valve type during design on the proper use of each valve type during operation. By the end of this course, you should be able to visually identify many common both types on no for which application they are best suited. So let's do a short recap. We can see that there are many different types off valves such as globe gate ball, plug, etcetera. There's one is missing on this list and that is the needle valve. And we're also gonna talk about that later in the course. In the next lesson we're actually look at is why we have valves in the first place on the functions of a valve 6. 05 Purpose of a Valve and Construction: how construction a valve control system or process fluid flow on pressure while performing any of the following functions. Stopping and starting fluid flow varying or front wing. The amount of fluid flow. Controlling direction of fluid flow. Regulating downstream system or process pressure relieving component or piping overpressure . These are the five main functions off a valve. There are many valve designs and types that satisfy one form or off the functions identified above. A multitude of al types and designs safely accommodate a wide variety of industrial applications, regardless of type. Almost all valves have the following basic components. Body bonnet trim, which is the internal elements off the valve actuator. This may be a handle or a hand wheel, or perhaps it will be pneumatic lee actuated or hydraulically actuated. They're actually four main types of actuator that we're gonna look at later. In the course on packing, which is used for sealing, the basic parts of the valve is shown below. I think it's very important that before we go too far into the course, you should learn all off the main valve component names so that as we go through the course and discuss each of the components and we go through the terminology will be aware off exactly what I'm talking about on this or aid massively with your level of understanding. Let's not go to next lesson. Look at some valve components. 7. 06 Rotary and Linear Motion Valves: throughout the course, we're gonna often refer to rotary and linear motion valves. Rotary motion valves are those that require only 1/4 of a turn to operate, such as a butterfly valve off the one we're looking at now you can see he is now fully open on. When you've rotates back. Their direction is now fully closed, so that is a butterfly Vowels. Rotary motion vowels are also referred to his core to turn valves because they only require rotation of 90 degrees in order to move from the fully open to fully closed position. Another rotary motion about design would be the bull vow again. Now it is really closed, and now it is fully open. The big advantage with Rotary motion vows is that they are very quick or fast to operate. You only need to turn them 90 degrees, and then they are fully open or fully closed. The opposite of a rotary motion valve is a linear motion fouls. Linear motion valves are multi turn valves because they require multiple turns of the actuator in order to move from the fully open to fully closed position for a need of off. This is fine because each turn is proportional to the amount of flow going through the valve. And it's also sometimes slightly advantageous. Because, for example, if we look at a gate valve when the gate foul gradually moves from the fully opens fully closed position, we are less likely to get water hammer because the valve is opened. Gradually, it's open slowly. If we open the valve suddenly, then we're likely to get water. Hammer hole we could do on that will damage downstream components. So examples of Rachel Emotion vows would be the plug butterfly on ball valves. On examples off linear motion values would be the gate globe on needle valves. 8. 07 Valve Construction and Components: So let's have a look now at a valve and its construction and some of the main components. As you can see in front of us, we've got a valve. This is actually a globe valve. What does give it a little spin? What we're gonna do is work through the exterior, the vile first, and I'll explain to you the main components off the valve. And then we'll take a cross section of valve and I'll show you some of the internal components. So let's start a top at the top of the valve. We have what's called a actuator now an actuator. It maybe pneumatic or hydraulic, or it may be manually operated or perhaps even electrically operated, such as with the motor. But the actuator is essentially opening or closing the valve or moving into a position between opening or closing, which is known as frog cling. As we can see here, this is a hand operated valve is the hand will resume in. We can see some labeling on the right. We have clothes, and on the left we have open. This means if we turn the valve to the right, we will put it into the closed position on Stop the medium flowing through the valve. This may be a liquid or fluid or perhaps a guess, or we can turn it to left, which is to open a valve on again. We will then have a medium that flows through the valve. The set up for valves is always the same. It's always righty. Tighty lefty loosey try remember that. Otherwise you're gonna put the valve into the wrong position. Now let's sue. Now we can see the actuator. It's being turned to left. The valve is now open. I understand. Which is this spindle long screw shape has now come out the top. This is known as a rising valve because we can see that the stem is risen out off the valve . And if we go back the other way, the valve is now being closed. Is being turned to the right. The hand wheel understand, has gone back into the valve that's arising type valve. Soon now conceded that the stem comes down on bond can see it here, continuing down into the main valve body on at this point here, we actually into the ceiling arrangement will part the ceiling arrangement for the valve. So there's always gonna be some sort of the seating arrangement to stop the fluid or the gas passing between the valve on the stem and leaking outwards. So that is this ceiling arrangement that we're looking at now. I'm going to take a cross section of that later. So let's just to now, then war. You can see another area of interest here. This is referred to his opponent. The bonnet is held on by these array of nuts going around the entire top of the valve on the bonnet is designed so that we can open the valve and access the internals. The internal components are actually referred to as trim, so we're gonna access the truth. Almost all the house will have some form of bonnet because it is essential to be able to get in there and maintain the valve. However, there are exceptions to this. Some vowels are not maintained in this manner, especially some of the small of ours that have a lower monetary value. In other words, it doesn't make sense to repair them or maintain them. It's a lot easier and quicker just to replace them. Let's go down a bit further, we can see we've got a connection on the end. This connection with ALS, the holes these holes are actually for passing bolts fruit, and then we will use a boat and not arrangement to tighten the flanges. That is, if you look from the side here, this whole section that's referred to as a flanges on each end as a flat match, we can see another flinch here on the flank enables us to connect to the piping and support the valve between the piping. Typically, we're going to use nuts and bolts, although it is possible also to weld the flanges to the pipe work. Obviously, once you welded the valve to the pipe work, it's a lot more difficult to remove. And if you've used a not involved arrangement, but you're generally only uses welding type arrangement when the medium flowing through the valve is particularly hazardous now each of the flanges also has a ceiling arrangement. This allows us to seal the valve to the pipe, work on if we can see here. This seating arrangement is the black highlighted area we're looking at now. It has a reached profile. This helps it to seal. And typically we use a paper Gasquet or maybe a night trial rubber gasket on that will help us to seal the valves to the pipe work when we can in the nuts and bolts together. The main reason for the gasket is simply that if we tried to clamp to metal surfaces together, there would be some sort of leakage on. This is because when you press two metal surfaces together, they're both quite hard. So when you press them together, they don't see all very well. There's always some sort of a gap between them, and they shall use a very soft metal. So what we'll do? We use some sort of rubber or paper gasket on. We'll squeeze that between the two metal surfaces on, and this will then inform our seal. We can see the inlet on discharge holes. Not sure which is which have to have a look around. The valve can see here on the side that there is actually a flow indicator that is this arrow here. So the flow is coming from the left and going to the right. That means on the left hand side we have the suction or the inlet on. On the right hand side, we have the discharge for the outlet between the two. Flanges is actually the body of the valve that is the entire area between the two flanges. Sometimes people will also include the flanges as part off the body and the body houses. The internals of the valve referred to his trip. So let's now take a cross section so we can look at the internal components. Okay, so there we are. Now we can see some of the internal components, and as you can see, we've also added some labels. So let's do the same again. Let's start at the top. You can see uh, well as it's labeled there or handle will as it's been labeled on. We've got a yoke sleeve that allows us to lower and raise the stem that is effectively an anchor point on. Without it, we would just be spending the valve right or left, and we would not have any vertical movement. So the yolks leave allows us to draw the stem up or lower it down. That is essentially its main function. If we look off to the right now, we can see the label for the stem. We can see something girls, which refers to as a gland bush on the gland. Bush is used to press Dow onto what we refer to is a gland packing on the gland. Bush will press down onto the packing, and that will give us a seal. Now, gland packing has come a long way in the past 100 years. Traditionally, they would have used something like horse hair and they would have wound it together on. Then they would have inserted that in the area we're looking at now. Where this gland packing is that's the black three stripes area we're seeing on this sort of wound horse here would have been stuffed in there on. We would have used the gland bush to press down onto this coarse hair and squeeze it between the valve bonnet on the valve stem that essentially then forms are seal and prevent any liquid or gas, or whatever the flow medium is from leaking out off the valve. Now, obviously we come a long way since using horsehair, we now often use plastics or Teflon on it is a lot more durable than horsehair. The generals I mentioned that also would use you have been soaked in some sort of fat or oil to make it a little bit more durable and to allow the stem to turn more easily. The way the resealing arrangement actually works is if we got to the top here, we can see on the left hand side of the screen. Now we have a not stud arrangement. Hey, stud is essentially a boat, but without a head so we can see that the study has gone through the entire piece here, and it has to Nuts on the end. Sumi, there is one not And here is the other. Not so we're not using a knot bolt arrangement were using what's called a stud and study and nuts arrangement. And we're gonna clamp these two nuts down, and we're gonna do the same on the other side to switch back so you can see it on when we tighten these down. Were since she going to push this metal plates the top metal plate down on that isn't gonna push the gland pushing down this section off wheeling about here as the glam pushing get pushed down is going to compress the packing on as it compresses the packing. It is going to steal the space between the stem on the valve on it. And that's how we get our seal important to realize that we don't want to over tighten the top nuts and studs. Because if we do over tighten those nuts at the top on we pushed the gland Bush too far down onto the packing we're actually gonna do is squeeze the packing quite onto the stem on also the valve bonnet. This is going to create a lot of friction when we try and open or close the valve. In fact, it could be incredibly difficult to open or close the valve when someone has over tightened the packing. Let's go down now we're going past the bonnet. We can see that the bonnet has bean again sealed onto the body. There was another seal. Raise this black piece here and so resealed the body Lower piece to the bonnet, the upper piece on. We've sealed the stem to the bonnet and that's gonna be there. Pressure boundary area. So we're gonna be staying inside this space. We'll go around with my mouse now and that's very important. We want to ensure that we have as few seals as possible on where we do have seals. We want ensure that they are adequate and sufficient to prevent leakage. As we can see now we've gone down, down, down. This is the stent coming down on. We're going to finally reach what refer to as disk. The disk is also sometimes referred to as the lid. So this is the little The disc on the disk is going to sit onto a seat. Now let me just push play so we can get some distance between R C and disk. Okay, so we can you see that the disc has moved up. The valve is now indie open position. Let's have a look at the seat with seat. Is this area just assuming yeah, where I am with my mouse Now this is the seat and including the side peace. And we want the disk to come down and land on the sea and four, ideally, a perfect seal, and then we will prevent any flow through the valve. That is when the vow is in the closed position on when we want in the open position of lid will rise or will move away from the main seating area on. Then we were allowed to medium to flow through the valve. It is very important that the disk and see contact service areas are clean. I wanted to be a clean is possible because any debris or foreign bodies that gets stuck between the disk and the seats are essentially going to stop it from ceiling correctly. And then we're gonna have a valve that allows the medium to pass fruit when it shouldn't. So imagine for a moment that we had just, for example, a big piece of metal that got stuck across the valve. See here, and as that this came down, it tried to crush the metal, but unfortunately wouldn't be able to do that. And what we actually have is a gap between the seats on the disk to assume up to imagine a gap here on the fluid or liquid or gas or whatever is moving through the valve he's gonna pass through here on. Then we've got a leaking valve, or what we refer to is passing a passing valve and that is no good. We don't want that the idea of the valve is it can open or close. We can start or stop fluids flowing on. We can't do that if the disk and the sea and not perfectly ceiling together and we actually refer to this is seating. So the valve should seat perfectly. And if it's not seating perfectly, then we're not gonna have a seal. So when you look in a valve, ask yourself, What is it doing? And then how is it doing it on? Then apply the knowledge that you got from this video and you will have to figure out the rest. 9. 08 Valve Actuators: There are four main types of valve actuators he's on mechanical, electrical, pneumatic and hydraulic. Mechanical actuacion would include just a simple hand lever or a gear wheel. Example we're seeing now is a gear wheel mounted for a gearbox. On this is to rotate plug. This example is a electrical actuated plug valve resume in. We can actually see the table connection that is, this area here on the electrical cable would connect. We could change them. He plug valve position from open to close, inconceivable indication on the top off the actuator itself. Now we've got a pneumatic actuator. The pneumatic act trader is a lot larger because the pressure used is quite moved, typically between 60 a bar eight being quite high and that again is used to actually plug valve. The only other time remaining is the hydraulically actuated type. Hydraulics use a much higher pressure on because they using my child pressure, they require less space to install than a pneumatic electorate. Involve but hydraulically actuated valves. Do you have some downsides, such as the fact that you need to have a drink piping associate with the valves running all over the plant? We'll also need associate pumps Ondas A risk off contamination, which is far less than if you were using pneumatic valves on associated compressed air system. So those are the four main actuated types mechanical, electrical, pneumatic on hydraulic. 10. 09 Pressure Drop: when we refer to pressure drop across the valve were actually referring to the pressure differential off the inlet compared to the outlet. Now we actually want a very low pressure differential as thief low passes through the valve . The reason is that the pressure differential represents resistance on if we have a high resistance than we have a high pressure differential. This ultimately means that it takes more energy to get the liquid or the guests through the valve. Then, if we had a lower pressure differential with correspondingly lower resistance. So if we look at a gate valve, which is a type of valve with a very low pressure differential, the flow would come in on this side. On it will pass through the valve. The disk is fully closed now on day is now fully open. Noticed that disk is well out the way off the flow. Normally, it would be totally retracted into the bonnet, so the pressure differential across the valve is very low. It's one of the big advantages with this type of valve. We can see here with the globe valves that there is something totally different occurring. The flow is coming in at the bottom of the valve coming along here on it is then going to pass upwards, screw or wait for this to move, gotta pass up with here, and then it's going to flow out on the other side. We're going now. So all of this means that were actually rather than just flowing straight ahead, which is like what we would do for a gate valve. We've got a flow along here, then we gotta change direction. Then we got a slow up here and then we got to change direction on. Then we got to flow along this way. That's why this type of RV sometimes referred to as a dead body valve. They call it a straight flow valve, sometimes a straight body. But this is not true. It's Maura's ed body float design on the pressure differential across the valve is a lot higher than for a gate valve. So when we referred to Pressure Differential for other course, now you'll know it's a form or a measurement off resistance to flow 11. 10 Response Time: when we talk about the response time, what we're actually referring to is the amount of time it takes for the valve. Teoh actuate a move between the fully open to fully closed position. We're very, very true motion valve. You can expect the response time to be quite low unless is a gearbox involved. We have a linear motion valve. You can expect the response time to be a lot longer compared to a rotary motion valve. This is simply because leaning emotion valves are multi turn valves, so it takes them longer to get from the fully open, fully closed position or vice versa. So that's what response time is referring to. 12. 11 Length of Travel: when we refer to length of travel when talking about valves. The length of travel is the distance that the disc travels within the valve body, and it's a distance that the Disney's to travel from fully open to fully closed or fully closed to fully open. Don't really refer to much to length of travel in this course, but it's still a term that you should be aware off. 13. 12 Ball Valves: in this video, we are going to look at the ball valve on. We're going to explain to you how the ball valve works on some of its main components, and at the end of the video, we're going toe. Look at the advantages and disadvantages associated with this type of valve. By the end of it, you should get a feeling off where we can use the valve on what sort of applications. So let's first pause the animation for a moment and we'll do a little spin. You can see the ball valve on this side. We can see the body night. Is that the body slightly larger here? This is because this is where our four is housed. Go around here and see through the valve on there we go backgrounds, the cross section side. I'll take a full view on. We can have a look again, and it's symmetrical on the opposite side. He's got quite a unique shape. But in order to fully understand the valve and how it works, let's just take a cross section and I let the labels, although we're not going to talk in great detail about that right now, we'll do that later in the course. So here we have the whole valve, with some of the main components labeled the ball valve gets his name from the type of diskette employees, which is the ball that is this item here. And we could see now that the ball valve is in the fully open position, you can see directly through the valve. If we press the play button, the animation now will close the valve on. What we've effectively done is stop the flow. Notice that we only turn the valve 90 degrees so this type of valve belongs to 1/4 tone or 90 degree rotation valve family. Other valves. 1/4 turn would include the plug valve on the butterfly valve. As with all quarter turn valves, there are quite quick to operate. You can install a gearbox on the top, a planetary type gearbox, although this means you'll slow down the actuacion speed off the valves or what they refer to as the response time. As you can see that this is manufactured off a metal material looks to be stainless steel, as is the body itself. The seat is manufactured from a softer material on this is going to be perhaps Teflon or some type of your last time. Eric material, perhaps new cream or a stiff, rubbery type off material. This allows us to press the disc in tight against the seat. When we get a really good seal, we can see on top of the ball valve, the stem is connected to the ball valve. In what looks to be a little rich, we'll do. I'll actually just get rid of some of these parts so we can see what is happening, such as the body. Okay, so now we can see the stem connects. Get the labels as well. The stem connects into the top or in this groove on top of the ball. And that's what allows us to rotate the ball and open and close the valve. Notice that the shape it is rectangular, and this allows us to apply a high amount talk without deforming the top off the ball valve . Gonna talk about deforming or defamation. I mean, rounding off the top of the ball valve. So we've got quite a large area for the stent. Come into contact with the disc so we don't run the risk of rounding the top off the ball valve, which would mean then that we can't turn the ball anymore. There are three different types off ball valve. These are Venturi, reduced and for bore with a full bore the ball itself or have a flow passage going through it that matches the internal diameter of the piping to which it's connected. And this leads us on to some of the advantages and disadvantages off the ball valve. Ball valve itself, because it can open up to allow complete throw through the valve, has a very low pressure drop. That means the flow is almost unrestricted through the valve. That is one big advantage. Another advantage is that the valve can be actuated very quickly. You don't know requires 1/4 of a turn. Both of itself is relatively cheap, and as low maintenance costs, it requires no lubrication on. One of the final of anti is is that the ball steals very well against the seat on this reduces the likelihood off leakage. Disadvantaged with ball valve is simply that is very poor at front wing. In this respect, it's very similar to gate valve. If we were to fossil the flow through the valve, then what we end up with is a very high velocity flow between the gap between the disk on the seat when it's in the throttle position on this high velocity of flow could potentially damage the disk. All the sea on a powerful, no longer see correctly. So that is the big disadvantage with the ball valve is simply that you can only use it for honor off applications on not for frakking flow. As I mentioned previously, the seat that is used will often be constructed of the last primary materials will have some form of rubber neoprene Teflon, etcetera. This material is a lot softer than the disc itself, which is good cause it allows us to see the disc within the see very well. But unfortunately, it means we cannot use the valve for high temperature applications. If we do use the valve for high temperature applications, we will heat up. The seat on the seat will become quite hard and we will end up with what we refer to as plastic deformation. Once we have a plastic deformation, it means that the shape that the CDs in will no longer return to the shape that it was previously. And if this occurs, then what we'll have is leakage between the discourtesy on the valve will pass and allow flow through the valve, so that's a big disadvantage through this type of valve. It's not normally suitable for high temperature applications, so that is our A ball valve works. We've looked at the advantages on disadvantages. You have a rough idea that you can use this foul for on off applications. Not so much for high temperature applications on definitely no for frightening applications . 14. 13 Butterfly Valves: in this lesson. We're gonna look at the butterfly valves. We're going to look at some of the main components ongoing. Explain to you what the advantages and disadvantages are off the butterfly valve. Let's get stuck in. We can see here. We've got a butterfly valve to a short spin. This butterfly valve is actually electrically actuated valves. We can see that on the top here and see the voltage in the power etcetera on. That would be an electric motor. Got on the top. Some form of Indication concedes open on now it is closed. You just do. Now we can see that again. Opening up Andi. Then it's gonna move back to the closed position. When the disk in the center is in the closed position, we can see that is in line with the body. We just backed that up moment. It is in line with the body on it is fully closed, removed to the open position you can see is now fully open. On the disk is a line perpendicular to the body. So that's essentially how the butterfly about works. Just push play so you can see it going again. It's a relatively simple operation. This type of valve is 1/4 turn valve similar to the ball and plug type valves. That means it could be actuated relatively quickly, only requires 90 degrees off. Turn in order for it to move from the fully open to fully closed position. The larger valves you'll actually use a gearbox, which means the response time from fully open fully closed slightly longer. However, it does make it easier to actuate the valve because she using a gearbox, we look at the body starting at the bottom that she got quite a thin body compared to other types. Off valve on. We can see that there are also holds here. Would I ever screw bolting to this body and connecting directly onto flanges for a pipeline , for example, Or we could pass bold, starkly through on. We would then couple the flanges to the butterfly valve. This type of body design is called the lug way, for the lug refers to the bolts. They're attached to the butterfly valve body or passed through it on. The big advantage here is that the valve is quite thin. We've got a full bore passage. See the black area here. This would match the internal pipe diameter. So we've got full flow through the valve, almost totally unobstructed, especially when we see in the fully open position right now the distance dinner, which it normally would be. And the flow can pass through almost unobstructed. This gives us a very, very low pressure drop, and that is a big advantage, I said. Really, the valve is quite thin on this makes installing the butterfly valve quite easy. If we had a butterfly valve that was leaking and we needed to replace it and we would jack the pipes off from the right hand side on the left on, then we would be able to remove the butterfly valve and install a new one while the old one is being repaired. So we've got a considerable space saving compared to, for example, a ball valve, which is another type of quarter to involve. Go down to the bottom might be able to see a bit off the stem to spin it. It's important that the stem passes out of the bottom here and also out of the top. The reason it's important is because this helps the disc stay in the center off the valve on this helps to discuss, then see correctly. The's them will actually pass through here on will be retained by bushings on. We will then have some sort of seal, which may be an iron ring or similar resume out. We can see a black area here. That black area he's actually the seat on. This is usually a relatively soft material or soft compared to metal, and it will be rubber based or polymer based, and this allows us to press the disc into the seat. Andi. Then, when it's pressed into the sea, we will get quite a good seal and see if we can actually get the dis pressing into the seat . Now when you rotates backwards. Okay, so there goes. That disk is now pressed against the sea on. We have a seal. The disc itself will be connected to the stem by square or hex head, and that will be a slot in the top off the disk on. If it's not connected like that, the stem will actually be connected to the disk for aboard passage, so the stem will extend through here out of our here on. We were then have four bolts or four pins which connect the stem directly to disk. We have a look up here. We can actually see the stem is quite sure here they never connection with a gasket that is essentially a whole lots of fly vowels. What I've done now, that should just taking a cross section off the butterfly valve on will run from the bottom to the top again. And see here, we've got a retaining ring on the bottom and cap packing. You have a lowest them bearing in here. The bushing will also be within this area. Got the disk itself. We've got the seat. Black area here. You've got the upper sten bearing on. There will be another pushing within this space as well. Packing stack, land packing. All of that is for sealing purposes so that we don't get me leak each rex, you're gonna have some form of packing at the base of the valve as well. And then we have the chef on finally on the top. Here we have the actuator. So in summary, butterfly valves are very good at starting, stopping and regulating flow their quarter turn valves and they can be operated quite quickly. They only need 90 degrees of rotation to move from fully open to put it closed. Very good for large flow low pressure applications. Andi offer a significant saving in weight size of cost compared to other similar valves, such as the ball valve, a good handling Slattery's or liquids with a lot off suspended solids. This is because the seating area is actually quite large. The maintenance costs with this type of valve actually quite low on, there are no spaces within the valve where pockets of gas can accumulate. 15. 14 Diaphragm Valves: in this video, we're gonna look a diaphragm south. I'm gonna explain to you how it works. We'll look at some of the main components, and then we'll look at some of the diaphragm vowels, advantages and disadvantages along with some of its applications. So let's do a quick spin. You can see the one side of the diaphragm and how it would normally see it when it's installed. And also see here that we've got an indicator for flow. That means that the in ladies here on the outlet is on the opposite side. This type of valve is used for open closed on front wing applications. You can see that the valve is being actuated. Now it's moving up and down in a vertical direction. And if we zoom in, you can have a look at the dire from which is where the diaphragm valve gets. Its name can see the diaphragm being pulled up. Now the valve is in the open position. Diaphragm is now pressed outwards on a dire friend is in the closed position. Okay, so we've got the compressor. Is this item here? And that is what we're using to lower and raise the dire from the diaphragms. Actually quiet, flexible to be made awesome form of polymer material perhaps save rubber type material or something quite similar has to be flexible because it is going to be lowered and raised down by the compressor on it needs to be able to withstand potentially frequent operation. If we go upwards, we can actually see a piston. That is the blue area here on the piston is used to press down on their compressor. On also, to lift the compressor back up again. We've actually got to yellow connections on the side of the valve. These are connections to a compress their system on. We will either had impressed there to the top or the bottom on this is gonna push the Kristen up or down on the top of the valve. We've got an indicator for a position indicator. Andi, this indicates to us now that the Valdez open on now it closed. Press pours. We can see the over ring, which is used for sealing on another I ring, which is also used for sealing to stop the air on the top, passing through and going to the underside of the piston largest advantage with this type of 1000 is that it can be used for corrosive systems. Because the dire Fran is no metal, it will be made from, for example, of rubber like material. Because the valve body itself is also made from a polymer or plastic material, it can be used within systems where metal may react with a certain liquid or a guess on orders. Get around this problem. We were used a plastic body on the rubber like material to the diaphragm. If resuming now or pause animation, we can see that if we were flowing through the valve, such as we are doing now, we will encounter only the body on the dire. From there is the outlet. We'll zoom becau the bodies here and the daughter from on the bodies on the opposite side. And those are the only two parts off the valves that we were coming to contact with. This is a huge advantage if the flow medium is very corrosive or perhaps is toxic because fewer parts means a lower probability that we will have a leak. There are simply not as many seals, so they're not as many places where we can have leaks, and we also have the advantage that contaminants cannot get into the system. Perhaps we have a floating gas that has to be incredibly clean on, cannot tolerate anything more than one partner 1,000,000,000 of dusk or foreign particles I'm in this instance we can use a diaphragm valve because probability that we will get ambient air going into the system or that we will get a leak is very low. So it's a huge advantage with the stop valve. The disadvantage with the stop valve and this is common for a lot off elastomers materials such as the dire friend or plastic materials such as the body is that the materials become quite soft or malleable at higher temperatures. And if they're not soft, infallible, they may even become quite brittle. It would become brittle. It means, as its load and raised it will crack on. Then we will get leaking or passing through the valve 16. 15 Gate Valves: in this video we're gonna look at the date valve gave those quite interesting because it's one of the most common types off valve, and it's also one of the simplest. Let's take a cross section so we can actually have a look at the insides off the valve. So here we have a gate fell off, opposed to play button on. Then we can watch the gate valve operating or actuate ing. So now it's in there close position, and it's moving up to the open position. You can see the winter valve is fully open. There is very little resistance to flow passing through the valve. This is very good, because this means we're gonna have a very low pressure drop. So as the fluid or the gas is flowing through the valve, he's gonna encounter very little resistance, and we'll have a corresponding low pressure drop gate valves and normally used in line. That means they're used just to pass flow through, but occasion. You might need to close the valve and isolate the system, and that is what gate valve is. Four gate valves are only used for open and close. They're not used for front Lingle regulating the float. I'll show you why we look down here. The bottom of the valve concedes fully closed. Now that disk is pressed against the sea or pause it now it is only half open. So this is in the ruffled position. Problem with this is that firstly, the amount of flow through the valve is not proportional to the amount that this gate has traveled. So the disc section here has traveled up and he looks like approximately half way. But the flow through the valve is not gonna be half of the max flow capacity. The flow through the valve is no linear or proportional to the amount the valve is open. This means that when you actually opened the valve halfway, you're going to get a lot of flow between the disk on the body year and this is gonna be proportionally quite a large amount of flow with a high velocity. This high velocity off the leads to seat on disk where the other problem, apart from the high velocity, is the turbulence. As the flow passes through this small gap between the disc in the body, there is a lot of turbulence on This also creates a larger pressure drop, which again is what you don't want. This is resistance to flow, so gay valves are not very well suited to fraud. Cling. In fact, they should either be only fully open or fully closed. What were down here? We could have a quick look at the sea of seats. This area around here is normally either part of the body, such as a flat machine surface or use. Seat rings on seat rings are usually metal rings. The advantage of the seat brings is that if the seat becomes warn, you could just change the secret. So see brings make it easier to repair a valve, such as by repair, and see if it's leaking by simply swapping the rings out. In order for the valve to seek correctly, we need both the disk on the seat to be machined flat so that they compress against each other and former seal. So we already know that we can potentially use seat rings and we can replace the seat rings if the seat surface becomes established. But that still leaves the disc. The disk is gonna be one of two designs, so they're gonna be inclined or parallel. There are three different designs for inclined discs. He's actually referred to a solid which split which and flexible which and then we have the parallel disk, which is not an inclined dissed. So the three designs that are inclined and one design which is actually parallel, which is too flat surface, is we're gonna talk about all of those disks desires later on in the course, as well as the seat designs, we move up, we can actually see the stem stem passes away through the valve bonnet through the seating arrangement on up through the handle wheel. This is interesting, because if we watch, we can actually see the stem rising out the top off the hand Well, on dropping back down again. So it's going to keep rising up and dropping back down. This type of design is what we refer to as a rising stem gate valve. Makes it really easy to see the position that the valve is in because systems just gonna out of the took in order to achieve this. What we've actually done is fixed the stem. What was that moment? Fix the stem to the disk so the stem is connected to the disk is not gonna move inside the disk or anything like that. It's totally fixed on That means that as we rotate the hand wheel, the stem is gonna be pulled upwards on. It's gonna pull the disc up. Is this a slightly different design to what they call a non rising stem gate valves? There are two main designs rising stem on non rising stem. As I said earlier, it's easy to see if the valve is open or closed. The downside is that sometimes you will carry bits of dirt on the stem here on when you close the valve like now the dirt etcetera will pass through the packing or potentially damage the packing, which will damage the seal on may be. Then you will get a leak. So contamination is a potential problem. We've rising stem gate valves by the big benefit is that you can actually see visually. If the valve is fully open or fully closed. We just take a look. Now, at a non rising type of gay path, this is a non rising type. Gate valve will explode out and I can show you the parts suit on the hand wheel bonnet, a smooth gasket for sealing to stem. And we can see the stem in comparison to the other design that we looked up as a Fred going all the way down. The reason that we have this Fred going all the way down is because as we opened the valve , Fred is going to screw into the disc to this section here is gonna go all the way through the disc as it screws into the disk. The disk is gonna be pulled up to stem as it's pulled up to stem. We're gonna open valve. So rather than having a rising stem, we're gonna have a normal rising stem because this is just gonna turn. And as it turns the D school move from here, the bottom part off the stem on it's gonna be dragged upwards, obviously, until it reaches the bottom off the disk. Typical service temperatures are gonna be between about minus 26 degrees Celsius. Pressures up to approximately 16 bath. The 1000 not suitable for very high pressures. Gosh, actually going to blow the packing our or course the packing to leak. So 16 bar would be the max service pressure on for flow rates. You're looking at anything between 5 to 20 meters for a second, depending upon if the flow medium is a liquid or a gas for liquids, the flow rate is actually to be less. So you're looking in the five meters max per second range on the gases you're looking up to maybe 20 meters per second. We're gonna look all of these aspects off the gate valve later in the course, and we're gonna go into a lot more detail. So let's now go to next lesson. We can have a look at the next valve design. 17. 16 Pinch Valves: today, we're gonna look at a pinch. Fouls. I'm gonna explain to you how it works. We'll look at some of the men components, and we'll also look at some of the pinch valves applications so we can see that a pinch valve is actuated at the moment. It is moving from the open position to the close position, but before we get into the details, let's first have a look at a pinch valve, how it would normally look. And this is how we would normally see a pinch valve, depending on the size. Designs do differ. We can see that it is incredibly streamlined. It has very few parts, and there's a very unique type of South compared to a lot of the other vows have been looking at, such as the Gate global on butterfly type valves. Let's take a cross section again and what I do like some labels. So here we have a pinch valves. The pinch valve is named a pinch valve simply because we are pinching this black item here from for to us a sleeve on. We're pinching sleeve together in order to close the valve. We'll see closing in a moment and now the valve is close. It could be no flow through the valve. We returned to our full view because cities totally opposed if we were trying to get through. Now you'll see there is no hole that is big enough on the fluid. Or perhaps the solids or gases would just be stuck on this side of the valve. However, if we release the pressure on the outside of sleeve, the valve opens on. We can go through the South. Pinch valves can be used for starting, stopping and regulating flow, but the effective frog cling range for this type of valve is between 10 and 95% off the Brady flow capacity. I think it's fair to say that the concept of the valve is relatively easy to understand. You could literally just imagine the thumb and fingers were pressing down or for grabbing his black Jube and pinching it or squeezing it together. That's gonna put in the closed position and we will open her hand on it's gonna put in the open position very simple concept. In order to achieve this open, close operation, what actually going to do is apply compressed air on this side through this whole on the compressed air when applied is going to squeeze sleeve together on it's going to close the valve. We can also then drain the air pressure off in order to open the valve again. This whole black area is called sleeve with the peace just outside of this leave being referred to as the cartridge that is this area here. We didn't have the valve body, this area here, andan in place. This area here which is screwed on to the body. There are very few components. As you can see, there is no bonnet. There is no packing. There is no stem. I really speaking. The disk itself is also the seat. So now we know how it works on. We've looked at its main components. Let's now have a talk about some of the advantages and disadvantages. Use associate ID with this type of valve. One of the biggest advantages with this time a valve is that the pressure drop through the valve is very low. The pinch valve, when open, offers almost unobstructed flow through the valve. We can see here that the pinch valve offers only a very small reduction in internal pipe diameter. This is section along here, and that means that we're going to offer very little resistance to flow, which ultimately is going to give us a very low pressure drop through the valve. Another big advantage with this type of valve is that there are very few components which also makes evolve quite cheap. As mentioned previously, this falcon be used to stop start regulate flow, which again is a big advantage when you consider that some other types of valves can only start and stop flow. Below are valve is new Merete actuated? It's also possible to hydraulically actuated pinch house. I think by far the largest advantage with this type of Valvo is that because of the low number off components, there are very few opportunities for the valve to leak, and they're also very few opportunities for contamination to get into the system. This means if we have quite corrosive substances flowing through the valve, they're gonna be fully contained by the sleeve on the body, and we can choose materials for the sleeve in the body that a very corrosive on Biro sieve resistant. The only disadvantage we pinch fouls, that is quite difficult to use a pinch valve within a system that has a vacuum. If we have a vacuum within system, this tends to collapse sleeve because we're effectively sucking sleep together, which is going to close valve. In order to get around this, we can actually apply a vacuum on the outside, off the sleeve between the body and the sleeve itself. On this counter acts the vacuum on the interior side of sleeve, which ultimately prevents the sleeve from clamping together and closing. Typically, fouled will be used for Slattery's that is liquid with a large amount suspended bodies. And this is because the seating areas valve is quite large. We press play. You can see now that the seating area, the valve stretches from here to here on, that ensures we get a good seal, which means evolve is not gonna pass, and we're not gonna get any leakage. These vials are also commonly used in pneumatic systems that conveyed solids such as Granules 18. 17 Plug Valves: today, we're gonna look at the blood vessels. I'm going to explain to you how it works. We'll look at some of the main components. Well, look at the advantages and disadvantages of this type of valve, and finally, we'll look at some of the applications of plug valves. So let's just take a quick look at the valve or pulls. The animation will go to a full view. We can see this is a plug. Valves is in the closed position when we can see that because the handle is perpendicular to the body, let's take a prosection so we can see the internal parts. Okay, so we can see the cross section. Now I'm going to zoom in, get a better look at the internal components, and we could play the animation again. Plug valves are quarter turn type valves. They're only require 90 degrees of rotation to go from the fully close to fully open position, or vice versa because they quarter turn valves like the butterfly valve bull. Those they are fast acting blood valve, as we can see, gets its name from the disc, which is shaped like a plug. We can see that the disk is installed within the body. This type of valve is used for open and close applications but is not suitable for fraud Bling. The reason it's not suitable is the same reason that we had for the gate valve. And that is simply that if we leave the valve in the half open position, such as now, the velocity off the fluid or the flow medium going through, the valve is very high, and this tends to erode our seat on disk. If we rode the seat and disk, then it won't seal correctly on the valve will pass. In other words, it would leak and will get flow through the valve. The pressure drop associated with this type of south is quite low. This is because when we open it, we can have either a four or passage, which means it's the same size hole in the disc as the internal damage of the pipe. Or it will be rectangular in shape, which is about 70% of the flow capacity compared to the full diameter off the pipe. If we have a full bore valve than the pressure drop is very low in the same manner as a ball valve is also very low. There's very little flow restriction with a rectangular valve. This is not the case because we have a restriction simply because the flow is reduced down to 70% off the total area off the internal pipe. So it is gonna be resistance offered by the valve on this. Resistance is going to slow down the flow through the valve and ultimately give us a larger pressure drop. There are two different types of blood found that you're likely to see. These are the lubricated on the non lubricated types. The non lubricated types used Teflon or plastic, which is installed at the base off. The plug on this piece of plastic will fit very flustered with the disc, and it will allow us to rotate the disk without any leakage occurring. Because it's Teflon and the material is softer compared to the disk, it can be considered self lubricating with a lubricated type of valve. We were used lubrication at the top and bottom of the disc, but the big downside here is that the lubricant has to be very suitable for the system. If we've got a fresh water system where people are drinking fresh water, then we don't want to use a lubricant. These hydrocarbon, based on may poison the people drinking the water or perhaps made them feel slightly unwell . So if we are using some form of lubricant, it has to be suitable for application, and we need to think about within which system it is used. My temperatures do affect this type off south. The high temperatures will tend to make the seats soft because the sea is made of a plastic or customer material. And if the C goes hot will and not with plastic deformation, which means the disc will no longer seat correctly on again, the valve will pass or leak. If we spin around here, we can see the valve actuator that is this red handle. So this is a manually operated quarter turn valve. It's gonna be quite small. Notice how big the handle is with respect to the valve body. So it's important to keep in mind that you're gonna need space to install not just the valve but the very long handle as well. It's not unusual that people install these blood valves on. Then they figure out that the handle doesn't fit, then they will cut it off, for example here, which ultimately makes it more difficult to open and close the valve. The advantages associated with the plug valve are that it is 1/4 turn valve, so it can be actuated quickly. If the valve uses a full bore passage, then the pressure drop freely available below. And what is quite unique about this valve is that it is suitable for multi port applications. It's imagine for a moment we were using a normal plug valve. If we add additional ports to the blood disk, then we can use the valve for multiple applications. This means that instead of having, for example, four separate valves, we could have one plug valve with a multi port design. So that is an advantage with this type of valve, and it is probably the biggest advantage. The disadvantage Dues are simply that this type of valve is only suitable for open close applications on is not suitable for fraud, cling 19. 18 Basic Course Final Thoughts: Okay, so a short video. Now, just to explain where we're gonna go with the course we've done the basic section on. If you just wanted to get an overview valves and what they looked like on some of the advantages and disadvantages, etcetera, then we've already gone through that. We've seen the three D models and the animations and stuff like that on the idea with Basic Val, of course, was to really just show you everything on Bond, let you learn it visually. So that was a sort of concept. You have a very general overview, but a quite a good one. I think. Now we're gonna move on with the advanced course. The advanced course is not as visual because you can only really take that so far. At some point, you have to read or have a bit of text sort of explained to you, and that's what we're gonna do in the advanced course, wherever possible. I have used animations or to the images or or anything like that photographs because this really helps with understanding, but only goes so far. So in the event, of course, you're going to see that there's a lot more written text. I've read it aloud, off elaborated with some my own case studies on examples where possible on Hopefully this will help you. I understand we'll get a deeper understanding of the whole topics. Off valves, particularly halal valves, are employed on bond what their applications are. So it's going with your vast course well done for making it this far. 20. 19 Welcome To The Advanced Course: so world. I'm finishing the basic course. We're not gonna be wrong with the advanced course. There is going to be a lot more information coming. The advanced course. It's not gonna be as visual, although wherever possible have tried to use to the animations and three D animations and three D models on just a bit of under standing and to make life a little bit easy for you. As you look, there will be a bit of repetition, so I'm sorry about that. I try to keep the whole thing going on, making fluid in a dynamic but recording these videos over the space of a month. It's kind of difficult to remember what did and did not teach on. I tried to, where possible. Just elaborate a little bit on some of the items. Again, I'm sorry if this is a little bit annoying me. Think I heard that about two hours ago, but it doesn't hurt just to do a recap on, I think. Ultimately, if you understand the concepts and the logic behind each of the valves and design features , you really does help when you're in the field because you can look at stuff on. If you no aware off what you're looking at, what? Actually forgotten some key details? Then you can analyze it logically. So we're not learning parrot fashion here. We're learning logic. When you actually understand al valves work. We need to understand what components were used on the reasons behind it. This is what engineering is all about. Sorry. It's going with the advanced course already. How you enjoy it. Good luck. 21. 20 Valve Body: fouls body. The body, sometimes called the shell, is the primary pressure boundary of a valve. It serves as the principal element of a valve assembly because it is the framework that holds everything together. The body, the first pressure boundary of a valve, resists fluid pressure lows from connecting piping. It receives inlet and outlet piping through threaded, bolted or welded joints. Our bodies are cast or forced into a variety of shapes. Although a sphere or a cylinder with theoretically be the most economical shape to resist fluid pressure, one of our eyes open. There are many other considerations. For example, many vowels require partition across the valve body to support the seat opening, which is a throttling or flow control orifice. With the valve, close loading on the body is difficult to determine. The valve in connections also distort loads on a simple sphere. On more complicated shapes, Ease of manufacture, assembly and costs are additionally important considerations. Hence, the basic form of a valve body typically is not spherical, but ranges from simple brock shapes to highly complex shapes in which the bonnet a removable piece to make access to the valve internals possible forms, part of the pressure resisting body narrowing of the fluid passage. Venturi effect is also a common method for reducing the overall size and cost of a vow. You know the instances, large ends added to the valve for connection into a larger line. So let's do a short recap here. We're talking about the valve body, and we're talking about the pressure of boundary can consider that to be the entire internal area off the valve body that is exposed to the flowing medium. In other words, it's exposed to the system pressure now. Ideally, we would just have a round shape or a spear, and that would be a valve. But unfortunately it is not possible because we have to connect piping to the valve. We also may need a bonnet or a place for the stem to pierce or penetrate fruit. The body and all of this means that we are creating what they refer to as stress raisers. Now, a stress razor is a point off weakness. In other words, if we had a flat metal plate or a fact, let's consider a a cylinder. We have a cylinder similar to a dive cylinder or a dive bottle on. If we drill a hole in the top of this perfect cylinder, we've created a stress. Fraser Stress Razor is an area where the stress residual stress off the material is higher than the surrounding area. The Bromley stress raises is that if they are too high, we were end up with cracks or what I refer to as crack propagation. So we wanna have a stress razor. But the stress raisers should be as low as possible. And this means that when the cylinder or the bottle is put under pressure, we will not initiate a crack around the stress razor on this crack will not propagate, which means it will not grow. The more holes we put into our cylinder, the weaker the shape off the cylinder becomes because we had him or and more stress raisers again. The problem here would be that perhaps we would get a crack and the cracked would propagate , and generally the trend is that the crap grows from one stress razor to another on this could lead to a catastrophic failure. So although we would like a perfect sphere, we would like to have the valve within the sphere this is impossible. So what we do is change the design slightly on. We try to world flanges on to the end, and we try to create the valve so that it can resist the system pressure despite the fact that is not the optimal shape. If this topic interest you and you want to learn more about crack propagation and stress raises, etcetera, then Google fracture mechanics on there. You we have to learn a lot about stress and strain on why it's so important in engineering . 22. 21 Valve Bonnet: sounds donor. The cover for the opening in the valve body is called the Bonnet. In some designs, the body itself is split into two sections. The ball together, like found bodies on its vary in design. Some bonnets function simply is valve covers or others. Support vows. Internals on accessories. Such a stent disk an actuator. The bonnet is the second principle pressure boundary of evolve. It is cast or forged. Of the same material is the body and is connected to the body by a threaded, bolted or welded joint. In all cases, the attachment of the bonnet to the body is considered a pressure boundary. This means that the world join or bolts that connect the bonnet to the body off pressure retaining parts. How on its lower necessity for most valves represent a cause for concern. Bonnets can complicate the manufacturer. Valves. Increased valve size represent a significant cost portion of the valve cost. Andi are a source of potential leakage. Now, just to clarify what I evolved, Bonnie is imagine you have a pumpkin on its Halloween and then you cut the top off the pumpkin off. Now you want to be able to put the top back onto the punkin and take it off easily so that you can get inside and change the candle, which is what people do at Halloween. This is essentially the same as with the valve on it. You want to take the money off on access the internals off the valve, which we know now is referred to as the trim, and you want to be able to maintain the internals off the valve on, maybe expect the interior off the valve. But then you want to be able to easily replace the bonnet and install it again so that the valve is again complete and whole. So that is the function off the bonnet. But bonnets are not fitted on to all types of valve. Some valves have no bonnet whatsoever. An example would be a pinch valve. If there is no bonnet than the valve can be considered to be stronger, then that was a vowels with aborning. When I say stronger, I mean structurally stronger, in other words, because we didn't have to cut the top off a pinch valve, for example, the pressure distribution is farm or even on. We have no stress raisers whereas with a gate valve where there will be a bonnet thes stress razor is the top of the valve body. At the point where the bonnet is attached, the bonnet has to be manufactured from the same materials as the body. The reasoning behind this is that the bonnet should be as strong or have a mechanical strength that is equal to that off the body. Another reason would be that due to thermal expansion, it's important that both materials expand and contract at the same race. This is what we call the thermal cover fishing off expansion or the coefficient of thermal expansion. It wouldn't make sense if we had a bonnet manufactured of a different material that when it gets hot or war, it expands significantly compared to the body, because this would lead to leakage as the gasket place between the bonnet and the body with no longer align correctly. 23. 22 Valve Trim: valves trim the internal elements of a valve are collectively referred to as a valves trip . True typically includes a disc, seats them and sleeves needed to guide to stem avows. Performance is determined by the disk and see interface on the relation off the disposition to the sea. Because of the trim, basic motions and flow control of possible in rotational motion trend designs, the disc slides closely capacity to produce a change in flow opening. When we talk here about rotational motion, I also referred to as Rotary Motion. So this is a rotary motion type off valve. This is actually a plug valve. Other types of rotary motion valves include the ball valve on the butterfly valve. So here we can see that the plug is in the middle. That's where the valve gets its name from Push Play will see the plug being turned 90 degrees or 1/4 of a turn on guys moving the valve from the open to closed position. So this is a rotary motion valve in lily emotions and designs. Disc lifts perpendicular early away from the sea so that an annular orifice is opened. We can see that with this valve here. This is a globe type of valve would again, with a pneumatic actuator on, we could see its position changing from open to closed. So there are two main designs off valve or to categorizations. One is the rotational motion or rotary motion type of valve. This is a ball or plug butterfly type of valve, and we have a linear motion type of valves, which would be a globe on gate house. 24. 23 Valve Disc and Seat: this and seat the valves having a bonnet. The disk is the third primary principle. Pressure boundary to diss provides the capability for permitting and prohibiting fluid flow . With the disclosed full system, pressure is applied across the disk if the outlet side is depressurized. For this reason that this is a pressure retaining part. Disks are typically forged on in some designs, hard surfaced to provide good wear characteristics. A fine surface finish of the seating area of the disk is necessary for good ceiling. When the valve is closed, most valves are named in part according to the design off the disks to see or seal rings provide the seating surface for the disk. In some designs, the bodies machine to serve as the seating surface and seal rings and not used in other designs. Forward seal rings a threaded or welded to the body to provide the seating surface, do improve the wear resistance off the seal rings surfaces often hard faced by welding on, then machining the contact surface of the story. A fine surface finish of the seating area is necessary for good ceiling. When the valve is closed. Seal rings are not usually considered pressure boundary parts because the body has sufficient all thickness that withstand the design pressure without relying upon the thickness off the seal rings. So we could see here that the disk for some types of valves is a pressure retaining part. That means that when the valve is closed, the side that is exposed to the system pressure is a pressure retaining part or forms part of the pressure boundary. So you said before that the pressure boundary includes the bonnet on the body on it can also include the disc. One important thing to realize here is well is that the disc itself needs to be strong or a strong as the body and the bonnet, but is the seating area that is our main point of interest on? In order for the valve to see graphically, the disc needs to be machines, so that has a flat surface which could be used to then press against the valve seat. And it's for this reason that they were normally machine the disk on the seats, and they will try to make the discord the seat off relatively hard erosion resistant material so that there is no damage to the disc or the seat in the seating area, and that means that there will be no leakage or it will reduce the likelihood of leakage. If we have leakage from the pressure side to the non pressurized side, that means through the disc or a gap between the disc in the seat. This is actually referred to as passing, and we will say the valve is passing. This is a problem because it means we can no longer isolate systems completely on the valve for life we need to be repaired or replaced. 25. 24 Valve Stem: stem the stem, which connects the actuator and disk, is responsible for positioning. The disc stems are typically forged and connected to the disk by Fred. It'll welded joints the valve designs requiring stem packing or ceiling to prevent leakage . A fine surface finish of the stem in the area of the seal is necessary. Typically, stem is not considered a pressure boundary. Part connection off the distance stem can allow some rocking or rotation to ease the positioning off the disk on the sea. Ultimately, the stem may be flexible enough to let the disposition itself against the sea, however constant fluttering or rotation off. A flexible or loosely connected disc can destroy the disk on or its connection to the stem . The two common types of valve stems are rising stems on non rising stems. These two types of stems are easily distinguished by observation, for a rising Stine valve stem will rise above the actuator as the valve is opened. This occurs because sustain is threaded on, mated with the bush in front of a yoke, is an integral part off or is mounted to the bonnet so we can see here that we have a rising and non rising type of valve. Here is the norm. Rising type on is the rising. The thing that you will notice is that as the valve is open on this diagram here, those stem pops out the top. You can watch. It's coming out about the top on out there. That is a rising stem gate valve for rising stem. It's very useful because you can actually see the position off the valve from away off. So if you're walking around the plant and you want to check the position of sir valves, this is gonna be a way to easily do that. You can just quickly look on your notice. If the stem is raised or lowered on, then you're most. The valve is open or closed. Have a look. Now the non rising type you can see here the non rising type is moving upwards, moving to the open position, but there is no stem popping out of the top. What's actually happening here? You can actually see it on the top. We have here a straight connection from the stem to the main gate of the dissed On it is more or less pulling the gate disc for the disk upwards with the number rising type. This isn't happening. What we're actually doing is we are screwing this stem into the disc, Andi. Then we are jacking off or screwing up the disc. So that's how it functions. There is no upward stem movement from outside the foul for a non rising stem design for the non rising stem designed the valve disk is Freddie internally on mates with stem threats. So, as they say here, we can fix the standard to the valve, and then we can raise it directly, quids on in this one. Here we will actually screw into the disk on that will pull disc upwards. So let's just recap. We can see that the one year is raising the stem on. We have a yoke, which is? This device on top of the bonnet on the yoke is essentially pulling disc upwards on the non rising type. We do not have a yoke. What we're actually doing is screwing the stem mawr arm or into the valve in order that we can open the valve on lift the disk. So two slightly different designs there. But they refer to a city rising on non rising stem types 26. 25 Valve Actuator: now actuators, some type of actor is necessary to allow for the positioning of evolve. Actuators vary from simple manual hand wheels to relatively complex electrical and hydraulic manipulators. Typical actuated designs include manual electric, pneumatic or hydraulic actuators. 27. 26 Valve Packing: Louth, packing most valves you some for packing to prevent leakage from the space between the stem on the bonnet. Backing is commonly a fibrous material. Such flax or another compound such Teflon. The forms a seal between the internal parts of a valve on the outside, where the stem extends through the body valve packing must be properly compressed to prevent fluid loss and damage to the valve stem. If a violence packages to loose the value of leak, which is a safety hazard, the packing is too tight. It will impair valve actuacion movement and possibly damaged stem, so packing is very important. Without it, we would have no seal between the stem on the bonnet. In the past, it was possible simply to use horsehair on some form of oil or grease over timing off. The backing will actually make it very difficult to actuator valve on. You'll also damage to stem as you very take the valve, you'll actually wear a groove into stem on. This will lead to leakage so important not to over tighten if possible. One of the methods I've seen is to record the talk that is placed on the pattern follower or, if you are using the valve for something like seawater or freshwater or Sweetwater, as you call it when you could actually do is tying up the packing up to a point where you believe it is seen incorrectly, and then you may open the valve to system pressure on. Then you can type in the packing up further until any leaking through the packing stops. Obviously, this is system dependent for water. It's not an issue. If you have a different material flowing through the valve for the packing, especially if it's corrosive or erosive, then you will be not using this tightening up method. Another problem with this method, if you're tightening the packing up whilst the valve is in service, is simply that you may leave deposits between the packing and the stem on. These deposits then will lead to where on the stem or the packing and potential leakage. So, ideally, you want to have the backing tightened up before it goes into service, so that you believe it's working correctly. And if it's installed on a system where you believe you can tighten up when it's in service and that's not okay. Obviously, as I mentioned before, though, you do need to be a bit careful. It really is system dependent 28. 27 Valve Functions and Basic Parts Summary: malfunctions and basic parts. Summary. The following important information in this chapter is summarised below. There are four basic types of flow control elements employed involved. Design while move the disc or plug into or against an orifice, for example, glow or needle type valves to slide a flat, cylindrical or spherical surface across an orifice. For example, gate and plug valves free right a a disk or re lips about a shaft extending across the diameter of an orifice. For example, a butterfly, a ball valve move a flexible material into the flow passage. For example, diaphragm and pinch valves. Valve stem leakage is usually controlled by properly compressing the pattern around the valve stem. There are seven basic parts common to most valves, so in summary, we've learned a little bit about each type of valve, such as how they open and closed. We've learned about linear and rotary motion type valves on. We've learned the basic compartments common to almost all valve designs 29. 28 Introduction to Valve Actuators: introduction to valve actuators. Valve actuators are selected based upon a number of factors, including the talk necessary to operate the valve and the need for automatic actuacion type of actuators include manual hand will manual lever, electric motor, pneumatic solenoid, hydraulic piston on self actuated. All actresses except manual hand wheel lever are adaptable to automatic actuacion. So what was then here is that all of these types of actuators can be actuated remotely and automatically, with the exception of the manual hand wheel on manual lever types. 30. 29 Valve Actuators: valve actuator. The actuator operates the stem and disk assembly, an actuator, maybe a manually operated hand wheel, manual lever, motor operator, saal annoyed operator, pneumatic operator or hydraulic operator. And some designs. The actuator is supported by the bonnet. In other designs, a yoke amounted to the bonnet supports the actuator, except for certain hydraulically controlled vowels, actuators or outside off the pressure Boundary yolks, when used, are always outside of the pressure boundary. So the actuator is gonna be installed normally on top, off the valve, away from the system pressure so it's not exposed to system pressure. It'll and we may have a hand lever like that show now. Or we may have a hand well, such as that shown now. Or it may be operated by a motor like the one we're looking at now. Or perhaps it will be a dramatically actuated valve, such as that displayed now, so there are different types of design. There are also the solenoid and hydraulic types off actuator. Generally, when we're using a manual lever, this is going to be for a relatively small or medium sized valve. A lever is typically only used for a 90 degree or quarter turn valve. This is simply because you only wanna turn it around 90 degrees. You don't want to wind it round and around with the lever. If you are doing that motion winding it around and around, then you're going to use a hand wheel for larger types, off valve or larger courts. During times of Alves, you're gonna use a gearbox normally, and then you're going to use the hand well again. She simply because you need a lot of talk to turn these larger valves, and you're normally not able to do that by hand, at least not directly. So you use a gearbox and you use a planetary style gearbox on your manually. Want the gear wheel that will close or open the valve proportionally. So in other words, you be able to apply very little talk on the hand wheel, but you'll get some incremental movement on the valve, so although you'll lose speed, you can't actuated valves quickly. It does make actually in the valve a little easier. Pneumatic actuators are a lot larger than hydraulic actuators are simply because the pressures are a lot smaller. A hydraulic actuated may use pressures up to 150 bar or more, whereas a pneumatic actuator typically may use eight bar or six part. This is what we refer to us control. Use different actuators for different things. A soul annoyed actuators ideal for on and off but is very poorly suited for fraud. Cling. So desire on or off with no flow regulation whatsoever. So below the valve design may be well suited for on or four front link. It is also the actuator that has to be considered. It's pointless having a globe valve that is well suited for front wing. If you're then gonna have a Solon oId actuator, there is only ever the position of on or off the solenoid. There's not gonna be the position in between. So having the globe valve there is not necessarily an advantage concerning flow control. You could just as easily have a different type off valve fitted, so the actuator has to fit the design off south in order that it could be applied correctly 31. 30 Manual, Fixed, and Hammer Actuators: manual fixed and hammer actuators. Manual actuators are capable of placing the valve in any position but do not permit automatic operation. The most common type of mechanical actuators. The hand wheel, this tie concludes. Hand wheels fixed to the stem have a hot wheels and hand wheels connected to the stem through gears can see here an example of a hand well actuated gate fouls. And, as we mentioned before, this is a non rising stem valve. Concede there is no stem popping out of the top off the valve. 32. 31 Handwheels Fixed to Stem: on wheels fixed to step on wheels fixed to the stem provide only the mechanical advantage of the wheel when these vows were exposed to high operating temperatures. Vow binding makes operation difficult her a few times here coming into play. One is mechanical advantage that is referring to the difficulty off opening or closing the valve. So when we say it provides mechanical advantage, we mean it makes it easier to open and close the valve. As an example, we could take a large ball valve if we wanted simply to pull a large ball valve from the open to close position. We have to apply a lot of talk, however, if we use that hand wheel or perhaps a hand well with the gearbox. We have a mechanical advantage because we can apply less talk on. We can close or open the valve incrementally. Another toned that we should be aware off school binding. That is, when the parts off the valve expand on, we will end up with a almost seized or blinded valve on that makes it incredibly difficult to operate 33. 32 Hammer Handwheel: hammer hand. Well, the hammer hand will moves freely for a portion of its tone on, then hits against the luck on a secondary wheel. The secondary real is attached to develop stem. With this arrangement, the valve can be pounded shut for tight closure or pounded open if it is stuck shut. Can see here a primary wheel Jeez in pink, the secondary wheel so we can see on the inside. Then we got Lux on day threaded stem. The hammer hand wheel is actually quite an interesting type of valve because we're able to wind the primary wheel slightly backwards on. Then get some momentum as we bang into the Lux in order that the lugs will then be hit by the hand well, and we can Frida valve if it's stuck in the open or close position. So that's essentially what we would have the primary were. It's so weaken, rotated, quickly, banging into logs and weaken jack the disk off the sea. Or we can put the valve again into motion. If it has seized or bind it 34. 33 Gears: years. If additional mechanical advantage is necessary for a manually operated valve, the valve on it is fitted with manually operated gearheads has illustrated below a special rent your hand wheel attached. That opinion shaft permits one individual to operate the valve when two individuals might be needed without the gear advantage, because several turns of opinion are necessary to produce one turn of the valve stem, your Creighton time of large valves is exceptionally long. The use of portable air motors connected to the pinion shaft decreases the valve operating time. Have a look. You got a manual gear head we've got is a manual hand well, and we can retake that on this. Will wrote. A secondary gear wheel on the secondary gear will rotate a much slower rpm, so this allows us to apply a talk to the hand wheel. And rather than trying to turn the entire vow through perhaps 1/4 quarter turn, we're gonna close it or open it incrementally. Now this is great because the talk applied is relatively low on. This reduces our chance off cheering stem whenever you apply a very high talk to a hand well or any type of actuator. All of that talk is placed on the weakest part, which is normally the stem. It's no unusual to rotate a hand wheel, especially when it's totally seized, or bind it shut on to share the stem at the point where attach is to the disk. Now, once you've done this, the first thing you'll do is sigh because you just made yourself a lot of work on. The second thing you'll notice is that when you rotate the hand wheel, it is suddenly freewheeling or free moving. In other words, because it's not connected to the disc anymore. It is incredibly easy to wind to stem up or down or to turn it in a rotary motion direction . So I do be aware that if you cheer stem or if it breaks, then you'll suddenly notice That is incredibly easy to operate the valve, and that's simply because you're not operating the valve anymore. All you're doing is operating the stem 35. 34 Electric Motor Actuators: electric motor actuators, electric motors permit manual, semi automatic and automatic operation of the valve motors used mostly for open close functions. Although they are adaptable to positioning the valve to any opening or closing point, the motor is usually a reversible high speed type connected through a gear train to reduce the motor speed and thereby increase the talk at the stem direction of motor rotation determines the direction of disk motion. The electric actuacion can be semiautomatic, as when the military started by control system. Ah, hand wheel, which could be engaged to the gear train, provides from manual operating off the valve limit switches and normally provided to stop the motor automatically at full open on full close valve positions limits, which is operated on the physically by position of the valve or Torsten early by talk of the motor. And we can actually see on electrically actuated valves here, receiving motor fitted on top of the butterfly valve. There are some advantages when using electric motors. The first is simply the when we're using a motor, the only thing we need to supply the motor with his electrical current. If we're using a hydraulic actuator, then we need to pump hydraulic fluid to the valve. It's a lot easier to lay a cable than it is to lay a hydraulic line, which you don't need to prime with hydraulic fluid. In addition to that, Elektronik cable has a lower fire load and is less of a fire risk. We can use electric motors to rotate either clockwise or anti clockwise, and we can also use a gearbox in order that we can rotate the motor and increase. The talker is applied to the stem. In addition to that, electric motors could be actuated remotely, such as by not greater sitting in the control room several kilometers away. So all in all electric motors have many advantages and can be used the numerous applications. 36. 35 Pneumatic Actuators: pneumatic actuators. Pneumatic actuators as illustrated below revival, automatic or semi automatic valve operation. These actuators translate and air signal into valve stem motion by air pressure. Acting on a diaphragm or piston connected to the step. Pneumatic actuators are used. Infertile vows for open close positioning. Where fast action is required is a video of a numerically actuated valves concedes actually plug valve because he's being moved from the open to closed position. Notice that the actuator, because of the low pressure of compressed air that issues he used is quite large. So we're gonna need a large actuator for the nomadic type of actuator. As mentioned previously, hydraulic actuators can be smaller because the pressure used in the hydraulic system is far greater. When air pressure closes the valve and spring action opens a valve. The actuators terms direct acting. When air pressure opens a valve and spring action closes the valve, the actuator is termed reversed. Acting duplex actuators have air supplied to both sides off the dire from differential pressure. Across the die from positions about stem automatic operation is provided when the air signals are automatically controlled by circuitry. Semi automatic operation is provided by manual switches in the circuitry to the air control valves. Let's go down. I want to keep the descriptions in the top of the screen. If possible, we can see here. This is a glow type half a globe said type valve on it is new, magically actuated. The springs are used to return the valve to its open position. On the air, pressure is used to close the valve. So this type of art is called direct acting. Because when air pressure closes the valve and spring action opens the valve, the axe raters turned direct acting. Another common way of referring to this valve is simply to say it is a closed spring open, so you'll hear a lot of times people say a close spring open or vice versa. That's telling you the air is used to close the valve on springs are used to open a valve. Personally, I find it so easy to remember if you can say that the valve these air closed spring open rather than saying the star if acting. But I suppose it depends on your personal preference 37. 36 Hydraulic Actuators: hydraulic actuators. Hydraulic actuators provide for semi automatic or automatic positioning of the valve similar to pneumatic actuators. Hydraulic actuators use a piston to convert a signal pressure into valve stem motion. Hydraulic fluid is fed to either side of the piston, while the other side is drained or bled. Water, oil or a mixture of both, is used as the hydraulic fluid, solemn vows that typically used for automatic control of the hydraulic fluid to directly open or close the valve. Manual valves can also be used for controlling the hydraulic fluid, thus providing semiautomatic operation quick. Now here. If we are using a mixture of water on oil, you'll actually hear this refer to as a emotion no se. It's an emotion hydraulic system on very, very, very large oil water systems, or where you require a lot of water for the actuacion of a valve, or perhaps raid very large pista. You use a mixture of about 98% water on 2% oil. If you ever visit a large aluminium or steel plant where they press a piece of aluminium in order to make a large cylinder, they essentially use a very large piston. They ran it against a block of aluminium or steel on, they forced the steel into the shape off a cylinder. Or they may just knock a cylindrical block out of the center of an aluminium or steel block . In order to do this, they need huge amounts off hydraulic fluid. This will be a mixture of 98% wards and to let's have a look at a hydraulic cylinder. Press it there can see. Now it's going to move from the left side to the right, so we're inducing flow on the left side. On that, I dropped fluid as it flows in the left is gonna Brewster cylinder towards the right, and that would be how we actuate a valve. We're, in this case, a culinary Moshe involved before we go to next lesson. What's actually quite interesting with these 98% water, 2% oil emotion systems is that one of the biggest dangers is actually bacterial growth. There are some types of bacteria like to live in the oil, and they will actually live quite happily in the oil. Andi spread very quickly in the same manner that you can sometimes get bacteria growing and fuel, if this happens, is an absolute disaster, because this bacteria clogs up filters very, very quickly and gives off a sulfur or smelly odor in order to avoid this that she does it with bio side. And this kills off any bacteria and you'll actually sample the oil water emotion system about once every three months. There's very slightly sidetracked there back after a bit of knowledge may be useful to you one day. 38. 37 Self Actuated Valves: self actuated valves. Self actuated valves used a system fluid to position a valve. Relief valves, safety valves, check valves and steam traps are examples of self actuated valves. All of these valves you some characteristic of the system fluid to actress valve, no source of power outside the system. Fluid energy is necessary for operation off these valves, so a good example of a self actuated valves would be every for safety valve on essentially the system pressure builds up on when the system pressure is too high, it will lift the disk off. The valve on the valve will be open. Then we'll push it into the open position. So you were using the system pressure to activate the valve. You're not using a hand wheel or any other type of actuator, although we've mentioned relief safety check valves of steam traps. Another good example would be a vacuum breaker. That is simply that if the system is placed under vacuum than the valve will open on, allow Andean air into the system. This is very useful for things such as silos or tanks onboard, a large motive, maybe vessel, because if we're pumping a liquid out of the tank. We need to replace that liquid with Andy in air or normally with ambient air on. The reason is, if we don't replace the liquid with ambient air, we're gonna put a vacuum on the entire tank on. In extreme cases, we can actually implode the tank, so that's the opposite of an explosion. We can have an implosion and the tank literally crumpled together on fall apart. I've actually seen this of one plant in Hamburg. They pumped the tank out, or they pump the liquid out. The breather on the top of the tank, which is supposed to allow air to flow in and out of the tank freely, was actually blocked with some form of vegetable oil because that was what they were working with and because the air can flow in and out of the tank freely, they pumped the liquid Allah's tank and they imploded or crumpled a tank together pretty much on then it fell over. So very important. Not only that relief valves are able to relieve pressure, but also the vacuum type vows can relieve under pressure 39. 38 Solenoid Actuated Valves: so annoyed. Actuated valves. Solenoid activated valves provide automatic, open, close valve positioning. Most solid wood actuated valves also have a manual override that permits manual positioning of the valve for as long as the override is manually positioned. Solar noise Position of our by attracting a magnetic slug attached to develop stem in single solenoid valves. Spring pressure acts against the motion of the slug. When power is supplied to Sahl. Annoyed, these valves could be arranged. That's the power to the solenoid. Either opens or closes the valve. When the power to the solar Norges removed spring returns of after the opposite position to solar noise could be used to provide for both opening and closing by playing power to the appropriate Saal. Annoyed. Consider some annoyed image there or an image of a solenoid valve. Single solid or 1000 turn fail open or failed closed, depending on the position of the valve. With the solenoid de energized, they'll open solid. My vows opened by spring pressure and closed by energizing the solenoid. They'll close. Solenoid valves are closed by spring pressure on open by energizing the solenoid. Double solenoid valves typically fail as is. That is the valve position does not change when both solid noise de energized. One common application of some bivalves is in compressed air systems such as those used to supply to pneumatic valve actuators, solenoid valves used to control the air supply to the pneumatic actuator and thus the position of the pneumatic actuated valve, a solenoid valve just to elaborate still anymore on this is essentially a coil off conductor or a coil conductor on. When you allow electrical current to flow through this school conductor, you'll create a magnetic field. If you put a piece of metal within the magnetic field, you can either pull it or push it in a certain direction. We actually call this attracting or repelling depending upon the north and south off the magnetic field. So it's a very important concept. If you don't already know when current flows through a conductor, it creates a magnetic field on. When you create a coil conductor, you can create a stronger magnet field and that magnetic field we're having north and the South. So what we have essentially done is put a piece of metal in the middle, and when we allow the current flow, it's gonna push the metal downwards or upwards, and that's going to change the position of the valve. Another important concept here is failed. Open or fail. Closed the systems where you they are safety critical. It's very important that they fail to the correct position as an example here. Imagine that we had a fire in an engine room. Now the first thing we want to do we have a firearm injury or any type of plan is to completely isolate any fluid or gas or mixture that may aid the fire or worsen the condition. So if a fire alarm actuate within a machinery space, we want automatically closed the diesel valves. We want to automatically close the methane gas valves when a close off any liquid or gas that is going into the machinery space and for this will use a fail safe, valuable, failed, closed type of valve. This means that upon power loss in the event of a fire, perhaps the valve will close on. That means that no more diesel or flammable mixtures or gases liquid etcetera will enter the machinery space. Now it doesn't necessarily have to be upon loss of power, although usually it is, it may be that the file on actual rates we still have power. But we will cut off the power to these particular valves, and that means that we've completely isolated the machinery space. If you've ever visited a public building such as a hospital, you may notice that doors are held open by magnets on the doors are usually spring closed. What happens is the doors are held open by electromagnets on if the far along actuate it's will cut the electricity to these magnets. When we turn the electricity off to these magnets, the doors will then or close. That's a very unique and interesting design. It means that whenever there's a fire or far along, we can completely isolate Intar sections of the hospital. And these fire doors were all rated so that they last. For example, several hours before this design became available, every time there was a fire alarm, somebody would have to run around and quickly close all the doors or ensure that the doors were closed as much as possible. Typically, that hang a sign, and it says fire door, please keep closed. So these electromagnetic violence kind of get around that problem a little bit, although it's not unusual for people to put a door which underneath these fire doors in order that they remain firmly open even when the power is cut off. So as with everything in life, you can only help people so much. 40. 39 Speed of Power Actuators: speed of power actuators. Plant safety considerations dictate valve operation speeds for certain safety related valves. Where a system must be very quickly isolated or happened very fast. Vows actuacion is required where the opening of a valve results in injection or relatively cold water to a hot system. Slow opening is necessary to reduce the risk of thermal shock. Engineering design selects the actuator for a safety related vows based upon speed, power requirements and availability of energy to the actuator. In general, fastest actuacion is provided by hydraulic, pneumatic and Sahlin oil actuators. However, Sol annoyed or not practical for large fouls because their size and power requirements would be excessive. Also, hydraulic and pneumatic actuators require system for providing hydraulic or pneumatic energy speed of actuacion. Neither case can be set by installing appropriately incised orifice is in the hydraulic or pneumatic lines. In certain cases, the valve is closed by the spring pressure, which is opposed by hydraulic or pneumatic pressure to keep the valve open. Electrical motors provide relatively fast actuacion. Actual valve speed is set by the combination of motor speed and gear ratio. This combination can be selected to provide full valve travel within a range from about two seconds to several seconds. Let's go back to the top here. We can see one of the examples mentioned where the opening of a valve results in injection of relatively cold water to a hot system. Imagine for a moment that we had a valve leading to a boiler, and the boiler was relatively hot on the water. Being injected to the boiler was cold. This is thermal shocking. We don't want toe suddenly allow a huge amount called water into a very hot boiler because , well, thermal shock the boiler on. We may rupture or crack pipes if you don't know what film was. Shocking is. And imagine a car being outside on a very cold day. Same minus 20 degrees Celsius. If you boil water in a kettle and then you take the kettle outside and you pour this hot water, which may be in 90 degrees all over the glass of the car window. The glass window will immediately shatter. On that what were referred to his thermal shock? I have never seen a solenoid use for very large valve applications. This is simply because you would need a large saal annoyed a large conductor or a wound conductor on this generates a lot of heat, so it's not really practical also for hydraulic and pneumatic systems. If you have a lot of hydraulic and pneumatic actuators, that's okay. It's not a problem that obviously you also need to have a lot of piping to support the pneumatic and hydraulic actuators. So this is not always practical. When you have a very large plan spread over perhaps kilometers and kilometers, you don't want oh run hydraulic fighting all over the plan or pneumatic plating. I would say that generally it is possible if the plan is within a couple of kilometres or if it is maximum, say, one or two kilometres wide, that you could use pneumatic actuators, hydraulic actuators slain more difficult simply because you can need a lot more hydraulic fluid on the fire risk when pumping hydraulic fluid around. The plan is also far greater 41. 40 Valve Position Indication: love position. Indication operators require indication of the position of certain valves to permit knowledgeable operation of the plan with such valves. Remote valve position Indication is providing the former position lights that indicate if the vowels are open green or closed red remote valve position. Indication circuits. Use the position detector senses, stem and disposition or actuated position. One type of position detector is the mechanical limits, which which is physically operated by valve movement. Another type is Magnetics, which is, or transformers that sense movement of the magnetic cause, which are physically operated by valve movement. Local valve position indication refers to some visually discernible characteristic of the valve that indicates the valves position. Rising stem valve position is indicated by the stem position. Non rising stem loves sometimes have small mechanical pointers that are operated by the valve actuator. Simultaneously revolve Operation Power. Actuated valves typically have a mechanical point of that provides local valve position indication. On the other hand, some valves do not have any features for position Indication. Have a look on the example here we can see that we've used a needle or a position indicator to show the position off this globe valve. So normally the needle would actually have a red dot at the bottom or on a side plate and a green dot the top on we would move then between the open and close position on. We would know the position by looking at the color of the dot or a symbol such as, Oh, and see for open and close just pulls that one we can see here, some other type of indication. They plug valves numerically actuated valves to see on the top that has moved from open to yellow to closed, which is red. Just keep in mind that whenever you have an indicator, whether it be a pointer or a indicated like this on the top of the valve that the further away is from the disk itself, the higher the likelihood that if the stem breaks, you actually gonna get false Indication. What I mean here is that if the stem shears at this position here above the disc, which is not uncommon, then the indicator that you're seeing is more or less useless. All you're seeing is the position of the stem. As it moves up and down the disk itself. We sheared and no longer attached to the stem. The best kind of indicated that you can never see will measure the position off the disk itself on not the position off the stem. However, measuring the disc or the position off the disk is relatively difficult on. Measuring the position of the stem is relatively easy. Just keep in mind whether what you see is not always what you get revolves, and it's very difficult to problem solve or to find faults in a pressure line if you don't know the position of the valves with certainty. 42. 41 Valve Actuators Summary: do a short valve actuator summary. The important information in this chapter is summarised below. Manual actuators are the most common type of valve actuators. Manual act races include hand wheels attached to the valve stem directly and hand wheels attached three gears to provide a mechanical advantage. Electric motor actuators consist of reversible electric motors connected to the valve. Stem through a gear train that reduces rotational speed and increases. Talk. Pneumatic actuators used air pressure on one side or both sides off a diaphragm to provide the force to position a valve. Hydraulic actuators use a pressurized liquid on one or both sides of the piston to provide the force required to position the valve. Seoul Annoyed actuators have a magnetic slug attached to the valve stem. The force to position The valve comes from the magnetic attraction between the slogan a valve stem and the coil off the electro magnet in the valve actuator. So what we've done, there is recap on the different types of actuators. If you remember nothing else from this part of the course, just try to remember that we have five different main types off actuator. On these will be manual electric, pneumatic hydraulic on solid Lloyd type actuators 43. 42 Gate Valves: gate valves, gate valves, Isaly emotion valve used to start or stop fluid flow. However, it does not regulate or throttle flow. Main gate is derived from the appearance off the disc in the flow stream below. Immediately straight small gave valve used for common domestic applications. There we go. We can see a gate valves with solid. The main components labeled such is the actuator, which in this case is a hand well, Bonnie Screw Fred, which allows us to screw the Bonny into the valve body. Stay this on body itself. The disc of a gate valves is completely removed from the flow stream when the valve was fully open. This characteristic office virtually no resistance to flow when the valve is open. Hence there is little pressure. Drop across an open gate valves when the valve is fully closed. A distance you're in contact. Service exist for 360 degrees on good ceiling is provided the proper mating of a distance. You'll ring very little or no Leakage occurs across the disc when the gate valve is closed on opening the gate valves, the flow path is enlarged in our highly nonlinear Lana. With respect to percent of opening. This means that flow rate does not change evenly. Wrist and travel. Also, a partially open gate disc tends to vibrate from the fluid float. Most of the flow change occurs near shut off with a relatively high fluid, velocity causing Diskant seat where on eventual leakage refused to regulate. Float these reasons. Gate valves are not used to regulate or frontal float. Gate valve can be used for a wide variety of fluids and provides a tight seal when closed. The major disadvantages to the use of the gay fells are it is not suitable for threatening applications. It is prone to vibration in the partially open state. It is more subject to see and this square than a globe valves repairs such as lapping and grinding, a generally more difficult to accomplish. So again, it's too quick. Recap. Here we have a gate valve on memory retract on the open. The gate valves, or actually do is pull this entire disc upwards. Move it from the flow stream on because it's entirely removed from the flow stream. Pressure differential across the valve is low on. This is a good advantage. There's also very little turbulence because the flow just goes straight through the vials. Without any obstruction, we can also see the round seating area here. This was the 360 degree seating area we're talking about and that allows us to get very good type sealed. If we use of our for throttling, then what actually happened is we will open the vow halfway on. We will get a very turbulent path. The flow flowing underneath the disk or between the disk and the body on this turbulent flow often makes the valve chatter. Or it will make a vibrating noise is the disc wobbles back and forth against the body and it's gonna also damage to stay on in the ceiling arrangement. So gave hours very good for simple, open close applications. Also good ceiling, but really not intended for throttling 44. 43 Gate Valve Disk Design: they felt this design gate valves are available with a variety of disks. Classification of gate houses, usually made by the type of disused solid witch flexible wage split which or parallel disk solid, which is flexible wedgies and split wedges are used involves having incline seats parallel . This used involves having parallel seats regards to the style of wedge or disc used. This is usually irreplaceable in services where solid or high velocity made cause rapid erosion of the sea or disc. These components should have ah, high service hardness and should have replacement sees as well as discs. If the seats are no replaceable, seek damage requires removal off the valve from the line for re facing off the seat or re facing off the seat in place or in situ. Vows being used in corrosion service should normally be specified with replaceable seats, so the main types off valve. This design would be the solid, which flexible, which split which or parallel this. We're gonna look into these in more detail in the moment. Just keep in mind those names, if possible, on also keeping wind at the first free, which is to solid, flexible and split which is these are used where the foul has an inclined seat on the parallel disk is not. The parallel disk is used when there is no incline seat. In other words, the disk and the sea sit parallel with each other, and we'll check out some examples and extra lessons, so you can better visualize that on the final. But we mentioned, used to do with the seats and disks themselves on the factory leisure hardened surface. Or if they don't have a hardened surface to protect against erosion, they'll actually have easily replaceable seats or you'll be able to replace a disk. And this means that you can restore the valve to its original states for at least it will seal or seat again correctly. 45. 44 Solid Wedge: So if the four different gay about discs the solid, which is 1st 1 on our list, the solid which gate valve shown below is the most commonly used disk because of its simplicity and strength, evolve with this type of which may be installed in any position, and it is suitable for isil fluids. It is practical for turbulent flow. This is a solid which gave out design when we can also see that we see is inclined only lower piece here, up to the top, and that helps it is still better against the seat. 46. 45 Flexible Wedge: flexible, which the flex for wedge gate valve in Australia below is one piece disc with a cup around the perimeter to improve the ability to match error or changing the angle between the seats . The cut Berries in size, shape on death shallow, narrow cut gives little flexibility but retains strength. A deeper and wider cup or casting recess leaves little material at the center, which allows more flexibility but compromises strength. It's not looking a flexible which gave off, conceded design. There will talk for this in a moment. A correct profile of the disc are from the flexible. Which design can give uniformed deflection properties at the disc H so that they're waiting for supplies and seating will force the disc seating surface uniformly and tightly against the seat gate. Valves used in steam systems have flexible, which is the reason for using a flexible gate is to prevent binding of the gate within the valves when the valve is in the closed position, when steam lines are heated to expand and cause some distortion of our bodies. If a solid gate fits snugly between the CEO of our cold steam system, when the steam is easier than pipes Elongate is to say they expand seats will compress against the gate and clamp the valve shop. This problem was overcome by using a flexible gate whose design allows the gate to flex as the valve seat compresses it. A major problem associated with flexible gates is that water tends to collect in the body neck under certain conditions. The admission of steam may cause the valve body next to rupture. The bonnet to lived off or the sea bring to collapse following correct warned procedures prevents these problems. So a flexible which gave valve is similar to the initial solid, which gave out that we saw earlier. The main advantages with this type there are that we can have a cup around the perimeter of the disc, and this is going to allow it to see more easily and give us a better seal. So the tolerances for the flexible wedge seating are not a spine. As with the solid, which on this has already described for seem, systems is a big advantage because we're allowing some room for thermal expansion and contraction on the valve disk itself will still see correctly 47. 46 Split Wedge: So this is the final inclined disc for a gate valve, and it's referred to us. A split which split which gave Alves, is shown below or off the ball and socket design. He's our self adjusting and self aligning to both seating surfaces. Discuss free to adjust itself to the seating surface. If 1/2 of the dispute slightly out of the Lyman because of for a matter lodged between the disc half on the secret, it started wedges suitable for handling non condensing gases on liquids at normal temperatures, particularly corrosive liquids. Freedom of movement of the disc in the carrier prevents binding, even though the valves may have been closed when hot and later contracted to its cooling. This type of valve should be installed with the stent in the vertical position. So the big advantage with the split wedges that both sides off the disc are free to align on. To see no is the split, which is the last incline which gave bath design 48. 47 Parallel Wedge: Carol Disk Barrel Dis gave off is designed to prevent valve binding due to thermal transients. This design is used by flow and high pressure applications, which surfaces between the parallel face. The scarves are caused to press together, understand frost and spread apartment. This to seal against the seats, the tape in which is maybe part of this carves. Or they may be separate elements. The lawyer, which may bottom out on a rube of the valve bottom so that the stem can develop seating force. In one version, the way to contact surfaces are curved to keep the point of contact close to the optimum. In other parallel dis case to half did not move apart under which action. Instead, the upstream pressure holds the downstream disk against C carrier ring lifts the disks on the spring or springs, oldest afar and seated when there is no upstream pressure. Another parallel gate. This design provides for sealing only one port. In these designs, the high pressure side pushes to disk open, relieving the disk on the high press aside for forces to disclosed on the local society who such designs the amount of seat leak each tends to decrease as differential pressure across the sea increases. These vows were used at the flow direction, which will show which side is the high pressure. Side care should be taken to ensure that these valves are not installed backwards in the system. Some parallel disk A plows used in high pressure systems are made with an integral bon event and bypass line. Freeway valve was used to position a line to bypass in order to equalize pressure across the discs. Price opening. When the gate was closed, three way valve is positioned to vent the bonnet to one side or the other. This prevents moisture from accumulating in the bonnet. Freeway vowed his position to the high pressure side of the gate valve when closed. To ensure that flow does not bypass the isolation valves. The high pressure acts against spring compression on Foresee one gay off it. See three way valve. Inslee's float back to the pressure source so the barrel of this design is effectively a disk with two plates on either side. The idea is actually screwed down the disc into the closed position. It will apply a pressure trans firstly and push the two plates against the seat on this effectively are seal on a more pressure you apply than the more you're Presley's to place against the seating surfaces. So that's what way it works. The other way works is simply to use the pressure on one side of the system to push one of the plates against the sea, and that will give us a seal as well. Well, they should know, is where I'm pushing the two plates onto the sea. Now it's direction or are only pressing one of the plates onto the seat. So C is gonna be obviously a lot better if we have two plates or both sides of the disc. Precedent gets the seat rather than only one side of this pressing against the seat. 49. 48 Gate Valve Stem Design: gatehouse. Stem Design Gate 1000 Classified as I've arising stem or non rising steam valves for the non rising extend gate valve Stanley stranded on the lower end into the game as the have well on the stem is irritated. Gate travels up or down to stand on the threats. While the stem remains vertically stationary, this type of valve will almost always have appointed type indicator. Freddie Gone to the upper end of the stem to indicate valve position. The number rising stem configuration places to stem friends within the boundary established for the valve packing out of contact with the environment. This configuration ensures a stem merely rotating the backing without much danger of carrying dirt into the backing from outside to inside. So we can see a normal rise in gay bath notice. Essentially that the only difference is bottoms and small construction on top of the bonnet usually is a stem does not rise out top off the hand. Well, you'll see that in a minute with the rising gay path, rising stem gate valves, a design so that the stem is raised out of the flow path. When the valve was open, rises thin gate valves come into two basic designs. Some of the stent that rises through the how will, while others have a standard, is traded to the bonnet. He's a rising type, and we can see that the stem comes out of the top on. The difference we got on here is this construction, and that allows us to draw the entire disc anistan out of the valve. It's actually called a yolk. You could see on the other valve that we don't have that. The other difference here is that the stem as he's retracted, such as for here the number rising type it will through into the disk, and that is what lifts disc upwards. So that's a non rising type with the rising type. We're not screwing into the disk. It's attached to the disks. Solidly we're actually doing is screwing into a joke on. Then we're gonna draw up the entire stem on the disk rather than screw the stem into the disc. 50. 49 Gate Valve Seat Design: gate valve seat design seats for gay now's arrive provided into go with the valve body or in a secret type of construction. Searing construction provides seats, which are the threaded into position, or press into position and seal welded to the valve. 40. The latter former construction is recommended for higher temperature service. Integral seats provide a sea of the same material of construction is the valve body, while depressed in or fretted in seats for mitt, Variation rings with hard facings, maybe supplies to the application where they're required. Small forge Steel Gate House may also have hard faced seats pressed into the body in some Siri's. This type of valve in sizes from hearts or two inches, is rated for 2500 PS I steam service in large gate valves. Discs are often off the solid wedge type of seat brings fretted in, welded in or pressed in. Screwed in seedlings are considered replaceable since they may be removed on new seat rings installed. So there are two main designs for gay laugh seats. They're either gonna be directly integrated into the valve body. What I mean here is the valve body is gonna have a machine area that forms to see the downside. Here is, if a secret's damage, you could have two machine it again, and you can only do this so many times before the valve will no longer seek correctly, whereas you can also have Seat brings on. This gives you the opportunity to just change. The seat brings when they start to where this is a lot easier, more convenient than replacing the entire both. So replacing the seat rings and potentially the disk is a lot easier than replacing the entire valve as well as that's its considerable cost saving. 51. 50 Globe Valves: glowing valves. Bro Valve is a linear motion valve used to stop star regulate fluid flow is that body blow vow is shown below notice. It said. Flow path coming in from the left is going to go back up here and there across to the right . That's why it's called a sick body glow. Look at these designs in a moment is actually four different types of design has shown a path. The globe valve Diskant be totally removed from the flight path, or it can completely close the flow path. The central principle of globe valve operation is a perpendicular movement of two discs away from the sea. This causes the annular space between the disc conceiving to gradually close as the disk is closed. This characteristic gives the Globe valve good falling ability, which permitted use regulating float. Therefore, the globe valve may be used to boast stopping as starting fluid float on for regulating float When compared to a gate valve, a globe valve generally yields much less seat leakage. This is because the dis deceiver in contact is more right angles, which permits the force of closing too tightly. Seek the disc glove after the arranged discloses against were in the same direction of fluid flow. When the discloses against the direction afloat, the Connecticut New Jersey fluid impedes closing eight. Opening of the valve when the discloses in the same direction of float the kinetic energy of the fluid eight closing but impedes opening, this characteristic is preferable to other designs when quick acting stop powers unnecessary globe Thousands are drawbacks. The most evident shortcoming of the simple glow valve was the high head lost from to a war right and turns of flooring, fluid, obstructions and discontinuities and flow perfectly to head loss. In a large high pressure line, the fluid dynamic effects from pulsations impacts and pressure drops condemn is true stem packing and actuators. In addition, large valve sizes require considerable power to operate on our especially noisy in high pressure applications. Other drawbacks Off glow vows are the large openings necessary for disc assembly, heavier weight than other valves of the same floor rating on the cantilevered mountain of the disk to the step. So the globe valve, which we're gonna look at another video soon. See the design on this said type design actually leads to a larger pressure drop because the flow is not so direct through the valve, the some form of obstruction. So this gives us a lot of pressure dropped, which is not what we want. Do you want a lower pressure drop, however, the advantages that it seals relatively well because the disc, which is here, presses down onto the seat and gives us a good seal because it's a 90 degree angle. The amount of flow through the valley was a workload proportional to the amount that we open the valve. There's a gate valve. This is not actually the case. The gate valve. We can crack the vow, then opening slowly but in our flow through the valve is not proportional to the way open. Where is the decline Valdez? And that's what makes it much more suitable for fucking usually glow vows of being stored with the pressure on the lower side off the disk. Reason is, you want the pressure on the lighter side of this so that the pressure is not constantly applied to the bonnet on the ceiling arrangement. This makes it easier to open a valve that more difficult to close the valve 52. 51 Globe Valve Body Designs: clothe our body designs the three primary body designs for clothes, house ours. Everybody straight. Why body on angle? 1/4 less common type is the cross flow clove out design. We could see the full designs here straight, which is also known a set you see flow through. But the annular flow again flows up past the disc onto the rights or two left or wherever the triangle will be and cross flow. We're rejoining onto a different pipeline. And why, for again, which is a slightly different variation. What you gotta imagine here is it is a stem coming up to this point here. Another stem? Yeah, Just then. Yeah, I understand. Yeah. So the disk is gonna move this way or back up. Down, up, down, down. Those are four different flow valve body designs. 53. 52 Z Body Design: zit body design. The simplest design and most common for water applications is that body you can see on the image here. This is a zed body also referred to as a straight body or straight float. Not quite sure why it's referred to a straight flow because the passage isn't straight. We have this zed shaped here, or perhaps in the other direction for this body design gazette shape diaphragm or partition across the globular body contains the seat. The horizontal setting off the sea allows the stem and dish to travel at right angles to the pipe axes. The stand passes through the bonnet, which is attached to a large opening of the top off the Vow body. This provides a symmetrical form that simplifies manufacturer installation and repair. They were actually talking about here. Is that the stand? When it passes through the body, it will be going vertical through here on. This allows us them to make a relatively simple design bonnet, and simple designs are normally cheaper to manufacture, so that's the idea behind it. One thing that isn't discussed here, but perhaps should be, is that this said body shape actually gives us quite a significant pressure drop or perhaps not significant, but compared to, for example, a butterfly valve where the passage flows directly through the valve, this dead body design has quite a large pressure drop. So that's the drawback with this type off design, although you are able to regulate the flow using this design. 54. 53 Y Body Design: why body design The blow image illustrates a typical widebody globe valve. This design is a remedy for the high pressure drop inherent in globe valves to see. Instead, my angled approximately 45 degrees. The angle uses straight to flow path. But full opening on provides the stem Bonnie and packing a relatively pressure resistant envelope. So he's, ah, why body glove out? Design on the idea behind this is simply to reduce the pressure drop through the valve, which, as we discussed a moment ago for the dead body, is quite a significant disadvantage. Why body globe valves, the best suited for high pressure and other severe services in small sizes for intermittent flows? The pressure lost may not be as important as the other considerations favoring the widebody design. Hence the flow. Passage of small, widebody globe valves is not as carefully streamlined Is that for larger valves, we can see why body design here, the flow coming in from the left on when the disk is retracted or put in the open position on the phone will pass through here as it's already mentioned, Widebody designs are better suited for higher pressures on severe service and is to be used where the pressure dropped through. The valve is not one of the main considerations 55. 54 Angle Valve Design: angle valve design. The animal body glow about design is a simple modification of the basic glow valve. Having ends at right angles, the diaphragm can be a simple flat plate. The fluid is able to flow through with only a single 90 degree turn on discharge downward more symmetrically than the discharge from an ordinary globe. We can see here an angle flow globe valve body design, with a flow coming through here when the disk is extracted or moved upwards on the floor would just go off to the right hand side. A particular advantage of the angle body design is that it can function as both a valve on a piping elbow for moderate conditions of pressure, temperature and flow. The angle valve closely resembles the ordinary globe. The angle valves discharge conditions are favorable with respect to fluid dynamics and erosion. So essentially, what we've got here is something that's very similar to a globe valve. But if we wanted to use it instead as a piping elbow, maybe we didn't have enough space to install a globe valve. Or perhaps it just makes sense to install a valve on angle like this one here, right angle. Then that is when we reduce an angle flow globe valve just to give you an example. One off the valves I saw when I worked on merchant Navy vessels and container ships. The design was very similar to this. In fact, it was pretty much the same on what would actually have here is the bottom of the ship. We call it the Kill, and it would be in line with this love flans here on. Then we would draw seawater directly up through the globe valve on. That is how we would then get seawater into the boat for cooling and for making fresh water . So it's a much better designs. We can end for a stem extending along here with an actuator, and we can open and close the valve. The pressure is also on the underside off the disk. Now, if we tried to do that with, for example, a normal globe valve would have to bring the piping up, then a right angling on. Then install the valve here on. We've got all of this piping, which has no valve. So if any of that piping, or if that piping should have a crack then we have a problem because we got no way to isolate that part off the piping. And if you're on a boat a crap, Seawater five is definitely not a good thing. So the idea is you can install a valve directly on the keel, and then the only bit that could really crack and cause elite is that bit below the disk and the body here. So there's an example of when you would use an angle flow type globe valve. 56. 55 Globe Valve Discs: Globe valves disks. Most globe valves use one of three basic disc designs. The ball disk, the composition disk on the plug disk. 57. 56 Ball Disc: full disk. The ball disc fits on a tapered flat surface. See, the boldest design is used primarily in relatively low pressure and low temperature systems . It's capable of throttling flow but is primarily used to stop and start float. So this type of disc is a very simple design is for low pressure, low temperature. It's quite common, but it's only used starting and stopping off floats and regulating. 58. 57 Composition Disc: composition disk. The composition disc design uses a heart nonmetallic insert ring on the disk. The insert ring created tighter closure composition. This are primarily used in steam and hot water applications. They resist erosion and are sufficiently resilient to close on solid particles without damaging the valve composition. This are replaceable. So really started disk we can actually just replace it on is resistant to erosion, which is very good when you're from playing the valve. Is this actually seat pretty well and is used for hot water or high temperature applications? 59. 58 Plug Disc: plant this because of its configuration. The plug disc provides better throttling than ball or composition disks. Blood This are available in a variety of specific configurations in general. There, all long on tapered. This type of disc actually is similar, or the concept is similar to, for example, a needle valve. We use a pointed needle shape in order that as we open the valve, the float will proportionally increase, so there's no massive increase or jumping float. And that's one of the reasons why or the main reason why it's very suitable for throttling applications. 60. 59 Globe Valve Disc and Stem Connections: Globe valves, disk and stem connections. Globe valves employed to methods for connecting disk and stem T slot construction on disk, not construction in the T slot design disc slips over the stem in a disk, not design the distance screwed into the step. We can think of the T slope as being a kind of weird shape. It's on the stem, which fits into the disc, or the disc slips over that shape on that allows us to then mechanically turn the disc on. This will allow us to open and close the valve. The other type of design, instead of having a weird shape that actually connects to the disk we're actually gonna have, is a distant screwed directly into the stem. So that would be a connection. Instead of having a strange shape, we would have screws that connect the disk to the stem. 61. 60 Globe Valve Seats: Globe valve seats. Global seats are either integral with or screwed into the valve body. Many globe valves have back seats. Back seat is a seat, an arrangement that provides a seal between the stem on bonnet. When the valve is fully open, the disc seats against the back seat. The back seat design prevents system pressure from building against the valve packing. So the back seat design is pretty cool, because when we fully open the valve or Rex going to do in order that the pressure does not get to the packing is we're gonna have a back seat and it backseat presses up from the disk on seals the area where the packing use. That means the packing is not under constant pressure, and this will ultimately prolong its working life. 62. 61 Globe Valve Direction of Flow: globe valve direction of float. The low temperature applications globe and angle valves are ordinarily stored so that pressure is under the disc. This promote easy operation helps protect the packing and eliminates a certain amount of erosion. Action to the sea and dicks faces the high temperature steam service glow vows installed so that pressure is above the disk. Otherwise, the stem will contract upon cooling and tend to lift the disk off the sea. When we apply the pressure under the disk, he just generally makes it easier to open the valve on. The big benefit here is that we isolate the system pressure to the undecided this on. That means there's no system pressure on the bonnet on, more importantly, the packing. So that's one of the reasons why we try and keep the pressure on the underside off the disc when the valve is closed and as mentioned here, it's talking about high temperature steam service on, with all of the parts expanding due to the coefficient off thermal expansion. When those parts cool down specifically, the stem stem will retract on it. Lift the disk off the seat on this, then causes the valve to pass. So that's the reason why when the valve is closed, the steam pressure was maintained on the upper side off the valve. In order, the stem stays warm and then we don't get the disk lifting off the seat because there's no contraction as stem cools down. 63. 62 Ball Valves: full house ball valve is a rotational motion valve who uses a ball shaped disc to stop or start fluid flow. Bull John below performs. The same function is a disk in the globe valves and the valve. Happiness turned to open the valves. The ball rotates to a point where the whole threw. The ball is in line with the valve, body, inlet and outlet. When the valves shut, borders rotated so that the holy perpendicular to the floor openings of the valve body on the floor is stopped and see here from one side off the full vowels. This is actually the exterior. We go down, we conceive the interior. You can see how cool in the middle on. We can retake the ball 90 degrees backwards, and that's gonna move it from the open to the closed position. Most full vow actuators or of the quick acting type. It's require 90 degree turn the valve handle it operated valve. Other bull Valek traitors are planetary gear operated. It started. Gearing allows the use of a relatively small hand will on operating. Forced to operate a fairly large valve. Some ball valves have been developed with a spherical surface coated plug. It is off to one side in the open position on rotates into the flow passage until it blocks the flow path completely. Seating is accomplished by the eccentric movement off the plug. The valve requires no lubrication and could be used for throttling service. 64. 63 Ball Valve Advantages: bul vow advantages. A ball valve is generally the least expensive of any valve configuration. Ondas low maintenance costs in addition to quick quarter, turn on off Operation Ball vows a compact, require no lubrication and give tight sealing with low talk in addition to what's been mentioned here. We've also gotta consider that ball veils can be full bore, and that means the pressure drop across the valve will be very low. 65. 64 Ball Valve Disadvantages: all of our disadvantages. Conventional bull vows have relatively poor throttling characteristics in a front wing position. The partially exposed seat rapidly erodes because of the impingement of high velocity flow . So the problems here are the same as for a gate valve. As soon as you throttle valve, the amount flow going through the ball valve is quite high, depending on how much you fall it. But the velocity off the flow past the ball or between the disk and see he's high on this causes erosion on. This means that we ball valve will no longer seat as it should do. Or it could lead to a situation where it's not seating greatly and the valve starts to leak . 66. 65 Ball Valve Port Patterns: ball valve. Pour patterns. Full house are available in the Venturi reduced and for port pattern. The full pour pattern has a ball with a boar equal to the inside diameter of the pipe. A full port pattern is what I would refer to as a full bore valve. We say four ball Where actually mean is that the flow through the valve is the same as the pipe diameter or the, you know, pipe diameter. So we allow the same outflow through the valve as we would allow through the pipe, and that way we get a very low pressure drop. 67. 66 Ball Valve Materials: full of our materials. Bulls, a usually metallic in metallic bodies with true produced from last time Eric materials. Plastic construction is also available. The resiliency to football valves are made from various last own merit material. The most common seat materials are often Teflon field, TFT nylon, Bouna end neoprene and combinations off these materials. Because of the last row Merrick materials, these valves cannot be used. Elevated temperatures care must be used in the selection of the seat material to ensure that is compatible with the materials being handled by the valve. So we've got different materials for both the ball to see on potentially the body, the ball and the body will be the same. Normally on to see is different what they refer to as the last time Eric the last time. Here, materials are materials resembling rubber, so they slightly softer. This is better because it allows us to press the disc into the sea, and there's a little bit of gift. The disk is harder than the seat on. It will press into the sea and give us a good seal. The butterfly valve has something similar. The sea is also made of a soft material and again that allows us to push the disc into the sea and get a good seal without any leaking. The last Oh Mary material is, unfortunately not so great at high temperatures. It will tend to become quite soft depend on what kind of material you using on. This isn't good, because maybe it will deform when the valve is closed when the disk is pressed against the seat and ultimately this mainly to the valve not seating correctly and passing. So you need to pay attention to what is flowing through the valve and what material with seat on the disks are made out off, particularly the sea. 68. 67 Ball Valve Stem Design: ball valve stem design stemmed in a ball valve is not fastened to the ball. It normally has a rectangle, a portion of the ball end, which fits into a slot cut into the board. This enlargement permits rotation of the ball as the stem is turned so you can see the top of ball valve here. You took it from one of our three D models and we just got on in Dent or recess on the stem would attach there, and we can just spin the ball around. Not sure if you realize, but one of the reasons why we actually have this rectangular shape on top of the ball is because we can apply more talk on. We have a lower risk off the metal shape on the top, deforming. If you ever used a spanner that has 12 points compared to a spanner that has, say six. The reason you have 12 is because it allows you to get at the bolt when you're tightening up, all the not at more angles, but the reason you have six with you using a different up spanner is because you want to apply more talk. I've often used a 12 point spanner on as you spin it, if you apply a lot of force or your dues around the age or for the bolt, whereas if you have a hex head spanner for one with six sides, you can apply a lot of talk and you don't run such a high risk of round in the top of the bowl off on. The same theory is here you have the square shape you can apply more talk on Did you? Hopefully. As long as you're not Superman, you want to form the top of the ball. 69. 68 Ball Valve Bonnet Design: bulls are born in design. Bonnet cap fastens to the body, which holds a stem assembly and bawling place. Adjustment of the bonnet captain emits compression of the packing, which supplies the stem seal. Packing for ball valve stems is usually in the configuration of die formed back in brings normally of TFT TV filled or TFB impregnated material. Some ball valve stems the seal by means of firings rather than packing. So here again we've got a typical ceiling arrangement. Will use some packing zor Potentially maybe rings. Got to be careful not to over time and the bonnet. As always, we don't squeeze the packing out or press it too tightly against the chef because this aware that shaft and eventually caused leaking so you can, depending on the system, install the Borneo or tightly after what you think is correct and test. If you can actuate the valve using the lever, it should feel firm but not too loose on. If you're using it for a fresh water system, you can install it. Andi, then see if it leaks 70. 69 Ball Valve Position: old valve position. Some bull vows are equipped with stops that permit only 90 degree rotation. Others deny if stops may be rotated 360 degrees with without stops, 90 degree rotation is all that is required for closing or opening a ball valve. When we talk about stops, we're talking about this small tag year on the handle, and if I can see it, no. Okay, so that attack here on the handle can be pushed or slid off the handle. Onda. When that occurs, the valve is no longer locked in position. And so what we would normally do is push this tack upwards, and then we can rotate the valve 90 degrees for the valve handle. Onda. We were then being a closed position, and then we push the tag back down on it locks into this space here where the arrow is indicating so that will then lock the handle to a certain position such as the closed position, and then that means that we can no longer push the vowel handle to move to the other position. They might be wondering why we do this. Well, the reason is that if we leave the hand or sticking out at night degree angle. So it's gonna be pointing in this direction here, perpendicular to the body. When people walk past, have a tendency to bang into or to come into contact with valve handles on. When they do this, they'll knock it slightly, and then the valve will move to the throttled position. Or perhaps they're working in the area and they reach up to grab something they pull on it on. Then they've changed the position of the valve handle on. This happens more often than you might imagine. Generally, the people working around the area if they don't understand what the valve is four they'll tend just to leave it in. The position they moved to the valve will remain throttled or worse, it will be in the opposite position to where it should be. So that's the reason why we lock the valve in place. We use these little tags that we can push up and then push down again. The handle indicates valve ball position. When the hand lies along the axis of the valve, the valve is open and see that this is open and if we turn it 90 degrees. It will then be in the closed position, so it's a good indicator of the valve position. When the handle lies in 90 degrees across the axis of the valve, the valve is closed, such as that, but we can see here used on a small domestic system. Some ball valve stems have a groove cut in the top face of the stem that shows the flow path through the ball. Observation of the group position indicates the position of the poor free Dubel. This feature is particularly advantageous on multi port fuel valves. You will see this sometimes that they will have lines on the top off the stem, and they'll be engraved. Will be grooves in dense in the top of the stem to tell you where the flow through the valve is going. This is very useful. If you have a three way valve, Boris pretty standard on a freeway valve because you need to know where you're sending the fluid. Another important consideration of the ball valve is that sometimes the ball that will be in the opposite position to what you think it is now. This is slightly confusing on. It's totally in country to what the South should be indicating. But you will see in very rare instances, particularly when you're working with fuel lines. Well, mobile fuel lines. If you see an aircraft being refueled or a ship a yacht, etcetera. They were often used ball valves there are in reverse. In other words, this would indicate that the valve is closed, and if we turned the handle perpendicular so it would be pointing this direction in upwards direction, then that would be indicating that the valve is open. It's a bit counterintuitive, but there is a logical reason behind it. The reason is that if we turn the valve perpendicular and we start bunkering or start transferring fuel from a tanker to a yacht or a boat or from a tanker to an aircraft, the chances of somebody walking past on knockin the valve he's always there. There is a possibility of that, or when we're carrying the valve around, the chances of someone dropping it quite high does happen when they dropped the valve or when the handle is knocked. If we're bunkering in the valve is open, they cannot. The handle on DNA thing really happens because the valve was open anyway. They won't be able to really knock the handle when it's in line with the body, because normally the valve handle will be as long as the body. That means that nobody is gonna be able to sort of accidentally knock it where it's gonna be quite difficult to do. So we're reducing the likelihood that somebody would accidentally open the valve. It doesn't really matter too much if they accidentally closed the valve slightly or close the valve. But it does matter if they accidentally open the valve. If accidentally open it, we're gonna end up with a fuel spillage. So for mobile bunkering, operations there often employ a ball valve. Is the reverse off a standard bull vow you might not see? That is not something that is very common. As I say. I've only seen it for mobile bunkering. Well, mobile fuel transfer. But just be aware that sometimes the valves can work the opposite way around 71. 70 Plug Valves: blood valves. Flood valve is a rotational motion valve used to stop or start fluid flow. Name is derived from the shape of the disc, which resembles plug. Flood valve is shown below simply form of a plug valve is the pet Coke. The body of a plug valve is machine to receive the tape it or cylindrical plug. This is a solid clock with a board passage, a right angle to the longitudinal axis of the plug. We can actually see an image of a blood vows here on this is the plug in center, and it fits into the body on a similar way to ward off returning nine degrees. We can open of our on returning back nine degrees, and we will close the valves in the open position. Passage in the plug lines up with the inlet and are reported about body when the bloodiest . Unlike degrees in the open position, solid part of plug block supports and stops fluid flow. Vowels are available neither lubricated or non lubricated. Design with a variety of stars of poor openings through the plug, as well as a number of plug designs 72. 71 Plug Ports: plug ports on important characteristic of the flood valve is it's easy adaption to multi port construction, multiple valves of white. They used their installations, simplifies piping, and they provide a more convenient operation than multiple gate valves. They also eliminate pipe fittings. The use of a multi port valve, depending upon the number of ports in the blood valve, eliminates the need of his many years. Four Conventional shut off valves, plug valves and normally used in non from bling on off operations, particularly where frequent operation the valve is necessary. These vows are not normally recommend if the throttling service, because, like the gate valve ah, high percentage of flow change occurs near shut off at high velocity. However, a diamond shaped port has been developed for frightening service, so plug valves can be useful. Multi port operation. Just imagine that you have a straight line that goes through the flood valve. Well, that would be one area where you could have an inlet and outlet. But imagine Turn the valve, Let's say 90 degrees, and then you would have another inlet on another outlet so you can have, for example, two inlets into outlets. That would be a multi port flood valve. This so's a bit of space because you can connect multiple pipes to the one valve on the one valve can be used instead off, for example, two separate valves, as with the ball valve on the gate valve blood valves by used for on off operation and not for front wing. However, there are different designs on bond. As mentioned, the diamond shaped port has been developed and that can be used for front wing. 73. 72 Multiport Plug Valves: multiple plug valves. Multi port valves are particularly advantageous on transfer lines on for diverting services . A single, more to poor valve may be installed in lieu of three or four gate valves or other types of shut off valves. Disadvantages that many multiple valve configurations do not completely shut off float. In most cases, one flow path is always open. These vows are intending to divert the flow of one line while shutting off flow from the other lines. If complete shut off the flow is a requirement, it is necessary that the style of multi port valve use that permits this or a secondary valve should be installed on the main line ahead of the multi port valve to permit complete shut off afloat in some multiple configurations. Simultaneous flow to more than one port is also possible. Great care should be taken in specifying a particular poor arrangement required to guarantee that proper operation will be possible. 74. 73 Plug Valve Disks: plugs, mouth disks, plugs are on the ground or cylindrical with a taper. They may have various types of port opens, each with a varying degree of area relative to the corresponding inside diameter of the pipe. Let's have a look at a ground pork plug. Round port plug is a term that describes a valve that has around opening through the plug. If the poor is the same size or larger than the pipes inside diameter, it is referred to as a full port. If the opening is smaller than the pipes inside down it, sir, the poor is referred to as a standard round port. Violence having stand around ports are used only where restriction of flow is unimportant. So if it is, just remember the rounds. Port, if it is larger than the pipes inside diameter you just referred to, is a full port. If it's smaller than the pipes in a diameter, then you were 30 to it. As a standard port rectangular port plug, the most common port shape is a rectangular port. The rectangular poor represented Lee 70% of the corresponding pipes cross sectional area. The rectangular port plug was the one that we actually saw when we looked at Freedy model earlier in the course. So if economy board that is, things go back because this is the most common type of blood valve that you're likely to see as mentioned only only represents 70% off the corresponding pipes cross sexual area, so the flow is gonna be less than for around four port valve. 75. 74 Diamond Port Plug: diamond Poor plug. The Diamond Port plug is a diamond shaped port through the plug. This design is for throbbing service. All diamond poor vows, a Venturi restricted flow type. This is a variation on the standard plug 12 on the reason we would have. This is simply if we wanted to use the valve for throttling. Personally, I have not seen one of these installed or I haven't worked with one before, so I can't comment too much on it. If you want to know a bit more about the Venturi effect, just go to a search engine and type in phone. Firefighting system. Venturi. On there, you'll see way Venturi effect is, or what the Venturi means. Adventure is used actually to draw phone into a pipeline, and then the phone mixes with water and you end up with a phone water mixture that is in use for firefighting purposes. That isn't exactly relevant to this type of valve, but I think it helps if you see an example. So if you go to search engine, just try type it in, then jury firefighting system, and then you'll be able to learn exactly what that is 76. 75 Lubricated Plug Valve Design: lubricated plug, foul design clearances and leakage. Prevention of the chief considerations in plug valves, many vowels there of all metal construction in these versions, the narrow gap around the plug can allow leakage if the gap is reduced by sinking the tape of blood deeper into the body. Actuacion talk climbed rapidly and galling can occur to remedy this condition. Siris of grooves around the body and plug pore openings is supplied with Greece. Prior to actuacion, applying grease lubricates the plug motion and seals the gap between the plug on body. Reese, injected into a fitting at the top of the stem, travels down for a check valve in the passageway past the plug top to the grooves on the plug and down to a world below the blood. The lubricant must be compatible with the temperature and nature of the fluid. All manufacturers of lubricated plug valves have developed a series of Republicans that are compatible with a wide range of media. Their recommendations should be followed as to which lubricant it best suited for the service. The most common fluids controlled by blood valves are gases and liquid hydrocarbons. Some water lines have these valves provided that lubricant contamination is not serious. Danger lubricated blood valves maybe as large as 24 inches and have pressure capabilities up to 6000 p. S. I steal, our bodies are available. The plug can be cylindrical or tapered. Essentially, what we're talking about here is the lubrication off the plug valve because of the design off the plug valve. If we lubricate the gap between the stem and the body, then it makes it easier to actuate the valve. So there are two different types of blood valve you can at the lubricated or long lubricated design. However, if you using lighter type valves, they're normally always gonna be lubricated. One of the important considerations here is that the lubricant you're using must be suitable for the system in which you are installing it. In other words, if you have a fresh water system and using the plug valve, you have to make sure that the type of lubricant you're using is not a hydrocarbon based lubricant because you don't want that lubricant leaking into your water supply, especially if it is drinking water, for example. So the top Lucan is very, very important. And keep that in mind whenever you're installing a lubricated plug valve 77. 76 Non Lubricated Plugs: non lubricated plugs. There are two basic types of non lubricated plug valves. Lift type and elastomers sleeve or plug coated. Lift. I vows provide a means of mechanically lifting the tapered plugs slightly to disengage it from the seating surface to commit easy rotation. The mechanical lifting could be accomplished with the camp. Were external lever in a common non lubricated plug valve, having in the last time a sleeve a sleeve of tear for E completely surrounds a plug. It is retained and locked in place by metal body. This desire results in a primary seal being maintained between the sleeve and the plug at all times. Regardless of the position, the TFC sleeve is durable. On dinner, it's all but a few rarely encountered chemicals. It also has a low coefficient of friction and is therefore self lubricating. So we've got the lift type where you'll actually lift the stem and the disk up slightly in order to rotate it or to make it easier to rotate the valve on. You've got another type, which I've seen quite a lot, which is the dfe type. It's also non lubricated on. This is where we have the stem sitting in a body off T F E on the tier fee will be, for example, square so it can't rotate on the bit. With the stem conexes round on the stem will sit in the TFG, Andre will be quite a tight fit. A tight seal, however, will be able to rotate the stem in the disc by easily because there's a low coefficient off friction. But there'll be enough resistance from the tear fee because it's pressing against the stem that we won't have any leakage. So that's how that elastomers sleeve works on the TV. You should be able to easily no sick asses within the body, and it will usually be white in color. 78. 77 Manually Operated Plug Valve Installation: manually operated plug valve installation. When he's stolen plug valves care should be taken to allow room for the operation of the handle, leave or wrench. The manual operators, usually longer than the valve on it, rotates to a position parallel to the pipe from a position 90 degrees to the pipe. Again, I think this is fairly obvious for a ball valve or for any quarter turn type of valve in each other, enough space to actuate the valve. I've seen many times that valves or quarter turn vows are installed in an inappropriate position, and this means that when you try and close the valve, you're pull the handle around on. Then you'll encounter a war or a bowl kid or another pipe. And obviously this is not a deal, because you wanna close the valve quickly and you can't do that because the pipes in the way or another vow for some of a obstacle on the next step that comes is that somebody comes and they cut the handle so that you can actually turn it correctly. But then the handle is half assed, long as it should be, which means you have to employ a larger amount of force. Remember, here we're talking about the moment. So the longer the handle is, if you apply force at the end, you need less force than if you're using a short a handle. But anyway, yeah, someone comes and cuts the handle and then we end up with a handle that's half a long as it should be so important that when the vows and store it should be installed correctly and it should be easy to operate the valve. 79. 78 Plug Valve Glands: plug valve plans. The gland is a plug valve is equivalent to the bonnet of the gate or globe vows glands Secure System assembly to the valve body. There are three general types of plans. Single gland screw gland, a bolted gland. To ensure a type valve, the plug must be seated at all times. Land adjustment should be kept tight enough to prevent the plug from becoming unseated on exposing the seating surface to the life fluid. Que should exercise to know over tightening the gland, which will result in a metal to metal contact between the body and the plug such metal to metal contact. Creating additional force, which will require extreme efforts. Operate valve. Okay, so a gland similar to a bonnet when we say single screwed or bolted gland were referring to how it's attached to the body as with the bonnet. And whenever we're working on any sort of sealing arrangement, it's important not to over tighten or under Thailand, because if we do that, then we're not going to get the seal that we require or we're going to damage the valve by pushing the stand down onto the metal body when it should actually be not ct directly on the body. If we do get this metal to metal contact, then it's gonna become difficult to operate the valve. And obviously this is know as the valve was originally designed and it's not we intended to operate the valve. So as always, we've ceiling arrangements and just the valve. In general, don't over Tighten under Titan. Install it correctly once, and then the valve will have a longer useful working life. 80. 79 Diaphragm Valves: No I friend bells, diaphragm valve, easily emotion valve that is used to start regulate and stop fluid flow. The name is derived for its flexible disc, which made through the seat located in the open area at the top of the valve body to form a seal. See here that the die from is the black wine comes up. What's on top of the diaphragm is called the compressor compressive pushes through the black guy from down onto this gray area here that was closed. A valve. See you throttle because it's coming down to the party. Open position on now is close to the CT gets devolved body on the lower side. The compressor has pushed it down until a valve is in the closed position. Diaphragms valves are, in effect, simple pinch clampdowns. A resilient, flexible diaphragm is connected to a compressor by a stud molded into the diaphragm. The compressor is moved up and down by the valve step, hence the die from lifts when the compressor is raised. As the compressor is lowered, diaphragm is pressed against the contour bottom. In this, straight for a valve or the body were in the weird tar balls diaphragm valves can also be used for frightening service. We're type is the better front involved, but as a limited range, it's threatening. Characteristics are essentially those of a quick opening valve because of the large shut off area. Long to see we're talked. I, from Valve is available to control small flows. He uses a two piece compressor component instead of the entire die from lifting off. The were when the valve is opened, first increments of standard travel ways and in a compressor component because is only the central part of the diaphragm to lift. This creates a relatively small opening through the center of the valve. After the inner compressor is completely open, they are to compress. A component is raised along with the compressor, and the remainder of the frightening is similar to the front wing that takes place in a conventional valve. Diaphragm valves are particularly suited for the handling of corrosive fluids, fiber, Slattery's radioactive fluids or fluids that must remain free from contamination 81. 80 Diaphragm Construction: diaphragm construction. The operating mechanism of a diaphragm valve is not exposed to the media within the pipeline, and sticky or viscous fluids cannot get into the bonnet to interfere with the operating mechanism. Many fluids that clock corrosion will gum up. The working parts of most other types of valves will pass through a diaphragm valve without causing problems. Conversely, lubricants used to the operating mechanism cannot be allowed to contaminate the fluid being handled. There are no packing glands to maintain a no possibility of stem leakage. There is a wide choice of available diaphragm materials. Diaphragm life depends upon the nature of the material handled temperature, pressure and frequency of operation. Some elastic merit dire from materials may be unique in their excellent resistance to certain chemicals at high temperatures. However, mechanical properties of any a lasting marriage material will be lowered at the higher temperature with possible destruction of the diaphragm or high pressure. Consequently, manufacturers should be consulted when they're used in elevated temperature applications, and here we can see a dire Fran. This is taken from interactive freely model that we saw earlier in the course. All a less stone Merrick materials operate best below 150 F. Some will function of higher temperatures. Baton, for example, is noted for its excellent chemical resistance and stability at high temperatures. However, when fabricated into a dire from baton is subject to lowered tensile strength just as any other last time, Eric material would be elevated temperatures. Fabric bonding strength is also lowered at elevated temperatures, and in the case of Etan, temperatures may be reached where the bombs strip could become critical. Fluid concentrations is also consideration for diaphragm selection. Many of the diaphragm materials exhibit satisfactory corrosion resistance to certain rodents up to a specific concentration on door temperature. The last of a may also have a maximum temperature limitation based on mechanical properties , which could be in excess of the allowable operating temperature. Depending upon its corrosion resistance. This should be checked from a corrosion table. So let's just have a quick look on a diagram here. The most important points from this lesson are simply that the internals off the valve, Bonnie the compressor, all of the parts, none of those air exposed to the flowing media. The only things that are exposed to the floor in medium are simply the die. From here, it's black area on devolve in a passage is inside the body, and that is it. So we can use the dire friend to deal with materials that are corrosive or sticky. Or if we don't want any contamination coming in from the stem, for example, and coming into the system, then we use a diaphragm valve. So Avery Unique valve in some respects because there's very few parts that come into contact with the flow medium. A pinch valve is Another example is similar to a diaphragm valve in this respect, but the weakness here is the elevated temperatures. In elevated pressures you die. Fran valve usually cannot handle them, so its temperature and pressure sensitive. But the big advantage is we don't run the risk of contamination, such as from stem or from a leaking bonnet, etcetera. So very good for corrosive or sticky substances. Toxic substances on the like 82. 81 Diaphragm Valve Stem Assemblies: diaphragm valves. Them assemblies. Diaphragm valves have stems that do not rotate Hauser, available with indicating and non indicating stems. The indicating stem valve is identical to the non indicating stem valve, except there longer stem is provided to extend up through the hand wheel. For the non indicating stem design, the hand will rotate to stem pushing that engages to Stanford's, moves us then up and down. As a stem moves, so does the compressor is paying to the stem. The diaphragm, in turn, is secured to the compressor. So Robin, having a dramatically actuated with diaphragm valve, shall go back. You just have a great look at so here we would have a control. That connection. We can remove these two connections because let's imagine that the bar was operated manually and then we would have a stem here. We've potentially some for believer or a hand well or some other way to push the compressor down in order to close the valve. You can see already that we have an optical position indicator on. If we made this shorter to stem, you wouldn't actually see any indication it could actually close the body at the top here on, which is sure to stand out here, and it moves up and down on its all encased within the main bonnet area. But because we've extended to stem through the bonnet, we can actually see the position of the valve on whether it's up or down. We can actually put markings here, such as a green mark of open or red foreclosed etcetera, the river of the year and the green above it on depend on where that line is. We can see the position off the valve. So that's what we talk about when we talk about a dire from indicator on stem assembly. 83. 82 Diaphragm Valve Bonnet Assemblies: diaphragm valve mourning assemblies. Some die from vows. Use a quick opening bonnet and leave your operator. Despondent. Is interchangeable with standard bonnet or conventional were type bodies. A 90 degree turn of the lever moves a diaphragm for open to full closed diaphragm. Vows may also be equipped with chain wheel operators. Extended stems bevel gil operators. Air operators on hydraulic operators. Many diaphragm valves they used in vacuum service. Standard bonnet construction could be employed in vacuum service through four inches in size on vows four inches and larger. A sealed, evacuated bonnet should be employed. This is recommended to guard against premature die from failure. See, your bonnets are supplied with a seal pushing on the non indicating types on a sealed pushing plus. Soaring on the indicating types. This design is recommended for valves handling dangerous liquids and gases. In the event of a diaphragm failure, hazardous materials will not be released to the atmosphere. If the material is being handled are extremely hazardous, it is recommended that means be provided to permit a safe disposal off the Karajan's from the bonnet. So there are a few different ways to actually actuate the diaphragm valves. You can use a lever on rotated 90 degrees like according to involve Andi. Normally or possibly, you will use a screw Fred type off actuator. In other words, when you turn the lever, you'll be rotating the stem of the screws reds in order to press the compressor down. Where's a rod? Options such as pebble gear operators, air operators, hydraulic operators? The one I have seen it is very common is the air operator. We can see that we're using your seal bushings or seal bushings. Person I ring, depending on the Bonnie, is a indicating or non indicating type. Essentially, these is just different ceiling arrangements in order to protect against leakage. If you do suspect the vow has been leaking into the bonnet exception and you want to take the valve apart and you need Teoh, take all precautions. Consider him PPE personal protective equipment, etcetera because you don't open the bonnet and then after contents from the system spilling out of your hands, particularly if the system contains a corrosive or dangerous liquids or gases 84. 83 Reducing Valves: reducing valves. Reducing valves automatically reduce applied pressure to a pre selected pressure as long as a supply pressure is at least a high as the selective pressure, as illustrated below the principal parts of the reducing valve on the main valve on top would seat involved that has a piston on top of this valve stem a knock wood seating, auxiliary or controlling valves, controlling die a friend and adjusting spring and screw. So here we can see a reducing valve. This is the one we saw earlier in Reduce Involved introduction video. Wrong what the text has said up here, I think a simple way to explain this is that we have a pre defined pressure that we want on the discharge side off the valve from its Imagine on this side, and as long as thesis apply, pressure exceeds the desired pressure. The desire pressure will always be obtained because we're using a spring here on the spring is held on the compression, this residual stress in the spring, so it's constantly trying to expand on. The pressure is constantly trying to compress the spring, and the balance that is obtained gives us pressure on the outlet if the supply pressures she dropped below the defined president. We want on discharge side, and it's no longer possible to have a discharge pressure or the discharge pressure that we wanna have. So it's important to supply. Pressure is maintained at a desired pressure on the destroyed side, or it should exceed desire pressure. Discharge side reducing valve operation is controlled by high pressure of the valve inlet on the adjusting screw on top of the valve assembly. Fresh air entering the May involve a system may involve spring in keeping the reducing valve closed while pushing upward on the main valve disk. However, some of the high pressure is bled to an auxiliary vow. On top of the main path. The auxiliary valve controls the admission of high pressure to the piston on top of the main valve. The piston has a larger surface area than the main valve disc, resulting in a net downward. Forced open the main valve. The auxiliary valve is controlled by controlling dire from located directly over the auxiliary valve. The controlling diaphragm transmits A downward force tends to open the auxiliary valve, the downward forces exerted by the adjusting spring, which is controlled by the adjusting screw reduce pressure from the main valve outlet. He's bled back to the chamber beneath the dire from to counteract with downward force of the adjusting spring. The position of the auxiliary valve and ultimately the position of the main valve is determined by the position of the diaphragm, the position of the diaphragm Mr Tone by the strength of the opposing forces, off the downward force of the adjusting spring versus the upward force of the outlet, which is pressure. Other reducing valves work on the same basic principle but may use gas, pneumatic or hydraulic controls in place of the adjusting spring and screw. So in a nutshell, what we have here is an adjusting screw on the top, and we will use that dusting screw to vary the amount of stress that is placed upon the spring. Remember, Spring has residual stress when it's held under compression or is forced Maura Maura under compression, there's gonna be more and more force applied outwards from the spring because it wants to expand again. So if we tighten up the adjusting screw on, we push the spring downwards. Spring can expand down here, so the spring will be held. Maura Maurin Compression. That means it's got more and more stored energy, and it's going to try and expand. The only way it can expand is downwards because it's expanding more, more downwards. The amount of pressure that is required to lift the valve on push the spring upwards increases, and that is how we regulate our pressure output. If we slacken the screw off, then there is less tension on the spring, and it does not feel the urge to expand as much. The residual stress is not so much there anymore, and that means we need less pressure to push the disc upwards, and ultimately we're going to get a lower pressure on the discharge side. 85. 84 Pinch Valves: pinch files. The relatively inexpensive pinch valve is the simplest form of any valve design. It is simply an industrial version off the pinch cock used in the laboratory to control the flow of fluids. For rubber tubing, see a pinch fouls design here now in the open position. How we conceive, warning the close position. What we've actually done is applied compressed air through this plug here on the compressed air tax or around the pinch valve. She's normally some sort of synthetic rubber, and it will push the rubber together and form a seal and close the valve. Beach house is suitable for on off on front wing services. However. The effective Fortney ranges usually between 10 on 95% of the rated flow capacity. Pinch fouls are ideally suited for the handling of Slattery's liquids, with large amounts of suspended solids and systems that convey solids dramatically. Because the operating mechanism is completely isolated from the fluid, these valves also find application where corrosion or metal contamination of fruit might be a problem. The beach control vowed, consists of a sleeve molded of rubber or other synthetic material on a pinching mechanism. All of the operating portions are completely external to the valve the moldy sleeve is referred to is the valve body been child Bodies are manufactured of natural and synthetic rubbers and plastics, which have good abrasion resistance Properties. These properties permit little damage, develops leave, thereby providing virtually unimpeded flow. Sleeves are available with either extended hops and collapse designed to sleep over appointment or with the flan stand having standard dimensions. But then one of most important things to recognize here is that the big valves, similar to a dire for involved, has no internal comm. Parents are exposed to the flow stream we can see here. The flow is passing through the valve. On the only bits are the valves that coming into contact with the flow is actually the synthetic material. The rubber just sleeve on. That is the only big that is touching or coming into direct contact with the flow. So this is a massive advantage. If the flow medium is very corrosive and that is a characteristic diaphragm valve also has on its what makes them very well, sooty to, while in corrosive applications were simply not exposing many valve parts to the flowing medium, pinch vows are incredibly cheap. Normally you can replace the entire P 12 or, if that's not possible, you can replace a sleeve and then quickly return the valve back service. 86. 85 Pinch Valve Bodies: beach Foul bodies. Pinch valves have molded bodies. Reinforce with fabric. Pinch valves generally have a maximum operating temperature of 250 degrees Fahrenheit 250 degrees Fahrenheit. Maximum operating pressure varies generally from 100 ps i for a one inch diamond evolve and decreases 2 15 p s. I. For a 12 inch diamond valve. Special pinch vows are available for temperature. Range is off minus 100 F to 550 degrees Fahrenheit and operating pressures of 300 PS I. Most pinch valves are supplied with sleeve off our body exposed. Another star fully encloses this. Leave with a metallic body. This type controls flow either with the conventional wheel and screw pinching device, hydraulically or dramatically with the pressure of the liquid or gas within the metal case , forcing this leave walls together to shut off flow. Most explosively valves have limited vacuum applications because of the tendency of the sleeves to collapse when vacuum is applied. Some of the in case valves could be used a vacuum service by applying a vacuum within the metal casing on, thus preventing the collapse off the sleeve. So there are some temperature limitations here. And you should be aware also from the dire friend valve that we saw earlier in the course that that valve was also limited by temperature and pressure. The beach valve is limited by temperature, as is a diaphragm valve, and it's also limited by pressure to some degree, because operating on the vacuum will essentially, who's the sleeve to collapse? She started. Look for a moment of the previous lesson could see here. If we had a vacuum within this space, we would get that effects. It's just going to force he valve into the closed position so it's gonna collapse. Inwards on the flow will stop. So that's the main reason why we wouldn't use it for a vacuum unless we use a vacuum on the opposing side as well. In order that it doesn't collapse are seen here. This is actually valid uses. Compress it, close the sleeve, and that is why we have the metal casing on the outside. Although it's also possible to purchase asleep on its own without the metal casing 87. 86 Butterfly Valves: butterfly valves. Butterfly House is a rotary motion valve that is used to stop, regulate and start fluid float. But a five hours are easily and quickly operated because a 90 degree rotation of the handle moves to disk from a fully closed to fully open position. Lives but a five hours actuated by hand wheels connected to distended for years provide mechanical advantage at the expense of speed. See a butterfly valve here? It's actually electrically actuated. We can see an electrical actuator on the top of the valve, but of five hours. Possess many events. Use over gate glow plug ball valves, especially for large valve applications. Savings in weight spaces costs are the most obvious advantages. Maintenance costs are usually low because there are minimal number of moving parts and there are no pockets to trap fluids. But a five hours especially well suited for the handling of large flows of liquids or gases are relatively low pressures on for the handling of stories or liquids with large amounts of suspended solids. But if I valves have built on the principle of a pipe damper Flo Control Element is a disc of approximately the same diameter as the inside damage over the adjoining pipe. It's rotates on either vertical or horizontal axes. When the disc allies parallel to the piping run, the valve is fully open. When the disc approaches the perpendicular position, the valve was shot. Intermediate positions for fraudulent purposes can be secured in place by handle locking devices. When we talk about handle locking devices were actually talked about is something similar to a locking pin. But the handle locking device here's who can see is a spring operated ball. You know me. Grab the valve handle here. A quote between your hand and thumb on you. Squeeze those two parts together on when they come together. You'll be able to then operate valve when you let go. The spring pushes the lower part, which is the locking device downwards on that will lock the valve into position again. So that's what they're referring to when we talk about a handle locking device. But a five hours are used to start stocking regularly flow so they're not like ball valves or gay powers that she can throttle can regulate flow. The biggest difference. We've got a 5000 other types is that when you have very large valves, very large diameter valves. A butterfly valve is usually a good choice because they way along less, and they require a lot less space in the pipeline. You can see that the butterfly valve is quite thin. It's a lot easier just to slide this in between two pipe flanges. Then it would be, for example, to install a big ball valve. It also meant replacing butterfly valve a lot easier, as is possible. Jack pipe flanges back slowly and slide the butterfly valve out and slide everyone. 88. 87 Butterfly Valve Seat Construction: butterfly valve. See construction Stoppage of flow is accomplished by the vowed disc. Ceiling against the sea is on the inside diameter periphery of the valve body. Many butterfly valves harmony last Omeri See against which the disc seals other butterfly valves have a seal ring arrangement that uses a clamoring on backing ring on a serrated edged rubber ring. This design prevents extrusion of the rings in early designs. Middle describes. Used to seal against the Middle C. This arrangement did not provide elite type closure, but did provide sufficient closure in some applications by water distribution lines. So we butterfly valves nowadays will use in the last time Eric Seat. This essentially means that the seeds quite soft compared to the disk on it, means we can press the disc into the seat in order to get a good seal. If you ever operated butterfly valves, you'll notice that feels slightly spongy when you're pressing the disc against the seat as a tendency to bounce away from the sea or it feels like it's springing backwards. And that is because the material is quite soft or compared to the disk anyway, and has a tendency to push the dis back out again. So normally, when you're operating a butterfly valve, what happens go often is your be turning the valve on. It will get quite stiff as you approach the seat or as you first touch to see, and then you'll give it a good yank. Well, let go. The handle on it will lock into place. So there is normally a lock in plate where the handle can engage with the plate on. It will stop the disk being pushed out by the sea. This is locked in place on when you come back to open the valve. You can actually put on the butterfly valve slightly towards the close position to take the attention off the the locking pin for the locking plate. You can then keep your hand on the trigger on the handle and move out of the open position . You let go off the handle on the valve will then be locked in the open position. See now if we can see that on the other, a butterfly valve, not on this one can see you here. There's a spring push this together in order that the valve could be operated on when you've moved into desired position will let it go. Loosen it and it will fit into onto a locking plate. So here we are, loaded up a three D model of the butterfly valves. You can see here on the top that we have this arrangement. That's Ah, locking plate. You can see at the moment the valve He's engaged with this pin and it is engaged in the closed position. If I pull the handle down or sorry if I pull the handle upwards or put my hand or thumb on the top things on the bottom, squeeze it together, this pin drop down and then I'm free to move the valve to another position. When I let go again, this came over here is gonna engage in one of these thoughts on the valves in the locked position again. 89. 88 Butterfly Valve Body Construction: butterfly valve body construction. Butterfly of our body construction bears. Most economical is the wafer type that fits between two pipeline flanges. Another type, the lug way for design, is held in place between two pipe flanges by bolts that join the two flanges and pass through holes in the valves. Outer casing Butterfly valves are available with conventional flans dens for bolting to pipe flanges and in the Freddie lend construction. So the most common type that you're going to see is the wafer or lug way for design. And this is a very thin body design with the bolts themselves. Your are they're going to get a design where the bolts passed directly through the wafer. Or you're gonna get design where the bolts passed through the piping flanges and connect into the butterfly valve body itself. Now screw into the body. But there's no a huge difference in the designs there. It's more just how the valve itself is connected. As mentioned previously, the massive advantage with a butterfly valve is simply that the body is so thin you really could cut piece of pipes like the shorter and insert one of these valves. You don't need much space. Important consideration when you are tightening up the piping to the Volvo is not to over tighten, because if you do, the seat will be squeezed on. This makes it quite difficult to close. The valve seat will be squeezed outwits. And in order to get a good seat, you're really gonna have to tug on the butterfly valve to try and get it into the closed position. Remember, normally is a locking handle. So unless you're really tugging hard on the handle and managed to get into the right place on the locking plate, you're gonna be in the wrong place. So to get to that position easily, you want to make sure that you don't squeeze the seat because cell make it incredibly difficult to reach SecuritE position on the locking plate. 90. 89 Butterfly Valve Disk and Stem Assemblies: butterfly valve Diskant stem assemblies stand and described butterfly valves are separate pieces. This is bored to receive the stem. Two methods were used to secure the distant of stem so that the disc rotates. A system is turned in the first mess food the disk is bored through and secured to the stand with bolts or pins. The alternate method involves boring the disc as before then, shaping the upper stem board to fit a square or hex shapes them. This method allows a distant floats and seek its center in the sea. Uniforms seating is accomplished and external stem fasteners are eliminated. This method of assemblies advantageous in the case of cover disks on din corrosive applications. In order for the dis to be held in the proper position, stem must extend beyond the bottom of the disk and fit into a bushing in the bottom of the valve body. One or two similar bushings are along the upper portion of the stem as well. The's bushings must be either resistant to the media being handled. We'll see also that the corrosive media cannot come into contact with them stems. Seals are accomplished, I'm unpacking and a conventional stuffing box or by means of O ring seals. Some valve manufacturers, particularly specialized in the handling off corrosive materials basis Dennis feel on the inside of the valve so that no material being handled by the valve can come into contact with the valve stem. If a stuffing box or external lowering is employed, the fluid passing through the valve will come into contact with the valve stem. So short recap We're talking here about how the stem connects to the disc. Generally, we're gonna have either extend that slots into the disk, or we're gonna understand that he's connected to the disc using bolts or pins. Bushings are used at the top and bottom off the disc in order to help the disc locate on. Also to allow the stem to rotate without putting undue wear on the receiving arrangement. Bushings are used to help the disc locate correctly. On these will be resistant, a type of media flowing through the valve on if they're not, then they will be installed so that they are behind the ceiling arrangement, which means there won't be exposed to the Floria medium depreciated type of sealing employed will be packing, which is installed inside the stuffing box or we will use rings spends on side of the valve on what the flow medium through the valve is so relatively few parts with a butterfly valve on that is one of the advantages off the butterfly valve. 91. 90 Needle Valves: needle Valle's in need of I was used to make relatively fine adjustments in the amount of fluid flow. The distinguishing characteristic of a needle valve is a long tape of noodle like point on the end of the valve stem. This new acts as a disc the long apart. The needle is smaller than the orifice in about see on passes through the orifice before the needle seats. This arrangement from it's a very gradual increase or decrease in the size of the opening. Needle valves are often used as component parts off other, more complicated valves, for example, there used in some types of reducing valves. 92. 91 Needle Valve Applications: needle valve applications Most constant pressure. Governors have needle valves to minimize the effects of fluctuations and pop discharge pressure. Needle valves are also used in some components of automatic combustion control systems. We're very precise. Flow regulation is necessary. 93. 92 Needle Valve Body Designs: Neil Valve Body designs. One type of body designed for needle valve is the past. Dark body lost our bodies, a common on globe types. A ball swiveling in the stem provides the necessary rotation for seating without damage. Bar stop body is shown below see years the pastor body for a new valve that was seen earlier in a needle valve introduction. Video Need of hours of frequent users meeting valves. Meeting valves are used for extremely fine flow control. The thin disco orifice allows for linear flow characteristics. Therefore, the number of hand wheel turns can be directly correlated to the amount of flow. A typical meeting both as a stem. We 40 threads per inch need of I was generally used one of two stars of stem packing. Another ring with TFT backing rings were a TFT hacking cylinder. New valves are often equipped with replaceable seats that use of maintenance Here. An example. Here this is, uh, needle valve. I think the most important by this lesson is to realize that yes, needle valves are used where precise measurement is needed on. The reason for that is is because when we open or closed the needle valve. The number of rotations that we are making to open or close the valve dictates the amount of flow going through the valve. So imagine we were trying to do this with a small gate foul. It would be almost impossible. There's such a high velocity when you crack open the gate valve that measuring the flow would be incredibly difficult. Also, as you open the gate valve, the amount flow going through the gate valve is not proportional to the amount that you actually opened the gate foul. That is not true for the needle. Valle's nice why it is favored, for example, meeting units or monitoring valves, where we need to know exactly what is going through the valve. I will say, though, on larger applications where it's not possible to use a leisure involve you use some form off flow meter on this. Flow me to maybe what they call a turbine flow meter, or perhaps, and ultrasonic flow meter. So if allies your applications needle valves are know as appropriate 94. 93 Check Valves: check vowels. Check valves are designed to prevent the reversal of float in a piping system. These vowels are activated by the flow of material in the pipeline. Pressure of the fluid passing through the system opens the valve. While any reversal of flow will close above, closure is accomplished by the weight of the check mechanism. Buy back pressure by a spring or by a combination of these means the general types of cheque battles a swing tilting disc, piston, butterfly and stop. 95. 94 Swing Check Valves: in this video, we are going to look at a check valve. Specifically. We're gonna look at a swing check valve on. I'm going to explain to you how it works. We're gonna local. The main components check valve is a valve that allows float in only one direction. Check. Now, they're also called clack valves or non return valves or one way valves. There are different types of cheque mouth, such a swing, tilting disc, piston, butterfly and stop valves. But one of the most common on one of the simplest in design is the swing check valve that were about to have a look at now. So let's take a cross section. So we conceive the internal components. Swim check valves can come in a straight body or widebody design. The one we're looking at now is a straight body design. We can see some of the components have been labelled, such as a gasket seat disk body on bonnet. The bonnet is designed to allow easy access to the internals off the valve. The internals of the valve are collectively known as the trim we can see. We have a bolt on the top in the center This is for perhaps mounting pressure gauge or bleeding the valve on. We have to lifting eye bolts on the right and left. Always have a series of bolts around the top for securing the bonnet onto the valve body with the gasket placed for sealing. The gasket is made of a softer material on the bonnet on the body in a gaseous squeezed between the body and bonnet. In order to get an effective seal, resume out, we can take a look at the seat on the disk. The seat is actually this area. Here it is where the disk locates onto the body where the disc presses against the sea is the ceiling area. This effectively separates the inlet side of the valve from the dissed our side. The disc itself is around metal plates, which swings back and forth and is connected to a hinge. Pin the hinge pin. He's like a heated Yeah, on a split pin is secured at either end to stop the hinge pin dislocating. The body of the valve forms the main pressure boundary within the valve, and at the end of the valve we have two flanges, which we can connect to piping using either bolts. Or perhaps we may also, well, the flanges to the connecting piping on the underside of the valve. We have two metal feet, and these feet will be used for when the valve is installed directly on the floor or a flat surface. Gaskets are used at either end off the valves, flanges and these gaskets I used to seal the valve to the piping on reduce the likelihood of leakage. It's now see other valve works we can see now that the disk is pressed against the seat. Unless the fluid pressure on the inlet side increases on overcomes the weight off the disk on the pressure on the outlet side, the disc will remain seated and the valve will remain closed. The exact point of which flow begins to occur is known as the crackling. Pressure will try to simulate that now, so the cracking pressure has already been achieved. The disk is now opening and flow is passing through the valve. We'll open the disk all the way as far as we can. Disk is now for the open resume out. We can actually see me they this time, but from a full section view disgracefully open and flow comm pass into the main body of the valve and then through to the outlet side. However, let's now simulate if flow comes from the opposite direction. If the outlet pressure exceeds Thean, let pressure the check valve. We'll close on. The disc will be pressed against the seat. That's what we're seeing now. The pressure at which there is no indication of flow is known as the ceiling pressure or seating pressure. It's now taken off a cross section so we can see how that works from the side that we can actually just remove the body we can see. We simulate the valve opening and then closing again. Sometimes you're noticed that the seat is slightly tilted. The reason that we tilt the sea is because it enables us to seek the disc more easily on the valve. Also, seats better, higher pressures. This type of valve is not well suited four systems where there are many pressure fluctuations. The reason it's not well suited for pressure fluctuations is simply because when the valve opens and closes rapidly, you may quickly damage the disc or the seat. If the discord the seat is damaged, the new valve will no longer seal correctly if the value is not sealing correctly. We have a situation which is called passing, which effectively means that fluid will leak past the disc from the outside to the left side. When they swing, check valve is fully open, the pressure drop across the valve from the inlet side to the outside is very low. This makes him very well suited for high flow, low velocity applications. Not only is the pressure drop across the vowel very low, but turbulence as the flow passes through the valve is also very low on. This is a significant advantage. In addition to that, it's also possible to change the seat rings on the disc in order that a leaking or passen valve can be repaired without needing to remove the entire valve itself. In the next lesson, we're gonna look a different style of check valves known as the lift check valve 96. 95 Relief and Safety Valves: relief on safety valves. Relief and safety valves prevent equipment damaged by relieving accidental overpressure of fluid systems. The main difference between a relief valve in a safety valve is the extent of opening at the set point. Pressure of relief off gradually opens. Is inlet. Pressure increases above the set point relief valve opens. Army is necessary to relieve the overpressure condition. Safety valves rapidly box fully open assumes the pressure. Seven is reached. Safety valve will stay fully open until the pressure drops below a reset pressure. Recent pressure is lower than the actuated pressure set point different stream. The activating pressure set point and the pressure which the safety valve resets is called the blowdown blowdown is expressed as a percentage of the actuated precious set point you see here. We've got a picture of a relief fouls that is one that gradually opens and gradually closes . Asi pressure increases above defiance set point. So if the pressure increases a lot above a set point the valuable open law. If it increases only a little bit above the set point, the valve will open a little bit. Safety valve. These are fully open or fully closed relief valves are typically used for non compressible fluids, such as water or oil. Safety vials are typically used for compressible fluids, such a steam or other gases. Safety valves can often be distinguished by the presence of an external lever at the top of the valve body, which is used as an operational check. As indicated below the system, pressure provides a force that is attempting to push the disk of the safety valve off its seat. Spring pressure on the stem is forcing a disc onto the sea. A depression stone by spring compression system pressure overcomes spring pressure on the relief our weapons assistant pressures Relieved Valve closes when spring pressure again overcome system pressure, Most relief and safety valves open against the force of a compression spring. Pressure set point is adjusted by turning the adjusting nuts on top of the yoke to increase or decrease the spring pressure. I see a picture of a safety valve who can actually load up this model in a moment, and we'll talk through some of the components and how it works. Important to realize here that we've been talked about pressurization, but we can also talk about under pressurization such as when we have a vacuum, and we use vacuum interrupters for that as well. The big thing to notice is the relief valve opens proportionately to the overpressure, where, as a safety valve does know, it is over fully open or fully closed. The set point is on. The valves is usually labeled and tagged on this music. No one can adjust the set point unless they cut. The tag will cut the wire, so this prevents anyone messing around with a valve or adjusted the separate when they shouldn't. There is a lot of legislation around safety valves, particularly how often they're surveyed and what they're set. Pressure is on who is allowed to set them on. This is for good reason is because in the past people used to gag the valves or they used to a Justin because the vowels were lifting on our oppression. They should have bean on what actually happened. These who have had some steam boiler explosions Now no one's allowed to touch the safety vowels wants to be calibrated on. They have to be surveyed, for example, of the 6 to 12 months to ensure their functioning, as they should be so highly regulated. Topic safety valves on a letter, especially if you're not likely to be calibrating the separate and lift pressure on whatever you do. Don't cut the tax showing the pressure. And who said it because in some countries this is actually illegal for highly critical steam generators or large steam generators, you almost always have to safety valves fitted on each one of these safety valves be rated for 100% capacity. That means if one is not working and the boiler will to Steve Generator, he was generating maximum amount steam. One valve is enough to discharge all of that steam generated by the boiler, so we've got effectively 100% redundancy. And that again is normally a legal obligation in most countries. For large steam generators, especially those in a power plant or used in heavy industrial areas, you always have to safety valves 97. 96 Pilot Operated Relief Valves: pilot operated relief valves while it operated really 1000 designed to maintain pressure through the use of a small passage to the top of a piston that is connected to the stem such that the system pressure closes the main relief valve. When the small pilot valve opens, pressure is relieved from the piston and system. Pressure under the disc opens the main really foul. Such follow bowels are typically solenoid operated, with the energizing signal originating from pressure measuring systems. This type of arrangement, such as pilot operate relief valves, is quite common. But when you're actually doing is using one system to control another. For example, if you were using a co two firefighting system, you may not want CO two cylinders connected directly to the main zero to distribution line . So what you want to do is completely isolate the cylinders and your measure the pressure on the line. Or perhaps send a signal from another area, maybe indicating if there's a fire or similar. And then you use the solenoid valve to burst discs on top of the cylinders on. Then these discs will release the pressure into the main distribution line to using one system to control another system to give you a slightly different example from the woman's mentioned here. If we were using one system to control another, we could take, for example, a common rail engine. We maintain the system pressure within the fuel line that goes to the engine at, for example, 100 bar. And then what will uses Sahlin Oil valves on these solemn vows will open or closed, depending on the electrical signal they get from the engine. If they get an electrical signal, some of our open and it will send hydraulic fluid to the injector. The ejector will open on the fuel we sprayed into the engine cylinder were into the combustion space if it was, for example, a diesel engine. So this is a common rail engine. We're using a solenoid valve to control the flow off fuel to the engine percent. Using solenoid valves open, open injector, and the ejector is more or less a spring loaded valve when the hydraulic pressure reduces. In other words, when the solenoid valve closes, there'll be a spring inside the injector, which were forced, injected, closed again. It's an example of using one type of valve in a different system hydraulic system solid or Valvano hydraulic system to control the injector valve within the fuel system. And it is a very simple concept to this pilot operated relief fouls. If you want a little bit more about it, you can also check out firefighting co two systems. They use a similar concept. They will not flood entire systems with CO two. They will keep a storage off co two cylinders within a certain space within a room on their use. Sahlin I valve or a pile of valve to actuate bursting disks, or perhaps to open a different valve on this valve will then allow the CO two out of cylinders on into the CO two distribution lines, and the concept is the same as for the pilot operating relief valves. 98. 97 Types of Valves Summary: types of valve. Summary following Important information in this course is summarised below gate valves generally used in systems where low flow resistance for a fully open valve is desired and there is no need to throttle the flow globe valves they used in systems where good throttling characteristics and losi leakage or desired on a relatively high head loss in an open valve is acceptable. All valves allow quick quarter turn on off operation and have poor throttling characteristics. Blood valves are often used to direct flow between several different ports through the use of a single valve diaphragm valves. Pinch valves used in systems where it is desirable for the entire operating mechanism to be completely isolated from the fluid butterfly vows. Provide significant advantages over other valve designs in weight space and cost the large file applications. Check valves automatic open to allow flow in one direction and C to prevent flow in the reverse direction. Stop check Valve is a combination of a lifted 12 on a globe valve and incorporates the characteristics off both safety relief valves. Air used to provide automatic over pressurization protection for a system, so those are all the valves that we looked at earlier. Now that we've gone through intercourse might be a good time to return. Go back all the way to the start and watch the short 10 minute introduction video again showing all the different types of valves and get a bit of a refresher concerning what each valve does its advantages, disadvantages except Tre. In the next lesson, we just couldn't do short wrap up, and then that will be the end of the course. 99. 98 Final Thoughts: So you made it Well done. I'm really happy to see you here. I hope that you enjoyed the course, and you've got a very big benefit from it. If you get the chance, go back to the basic course and do a recap, maybe in a month, because that's when you really cement everything that you've learned some good introduction because its star and just to get a general overview again after a month, it really does help you keep that knowledge and make sure that you don't forget some of the important aspects. Obviously, your waste free to go through the entire course again. The course is always gonna be here in its on line for you. I really hope that you can use your knowledge now on perhaps passed on help other engineers to learn from what you have learned. Because for me, this is one of the biggest gifts that you can give people. If you've got questions or comments, please do let me know. I'm more than happy to help you. If you've got feedback, this would be very valuable for me. Just give me a note and say, Hey, John, this lesson wasn't very good or it wasn't clear or hey, John, can we have an animation or perhaps a picture with this on? I'll do my best to improve the course. Of course, isn't static. It's dynamic one every single lesson on this course to be the best it can be. By the end of it. Maybe in a year or so we're gonna end up with the course. It's been revised 50 times on. It's gonna be the best course out there. So if you got feedback, I would love to hear. Thank you very much for your time, the time that you've invested in this course, and I hope to see you on the next course suit I want to know. 100. 99 Bonus Video - Pneumatic Actuated Globe Valve: today, we're gonna look at a dramatically actuated globe valve. I'm gonna explain to you how it works and we're gonna look at some of the main components. So here we have the exterior view of a dramatically actuated blow valve. Just refer to it as a globe path now, otherwise the video is gonna get quite long. So we've got the body of the valves. That's this section. But we're looking at the center of the screen now and then we've got the top of the body, which is held on by these nuts as referred to as the bonnet. The bonnet is essentially the top part off the body, and it's the piece that we can remove to get to the internals. In other words, if you need to maintain the valve, we think I stand in the middle, which sometimes people call the spindle. That's this vertical shaft going up the middle. There. We've got an indicator that is this arrow we uses to indicate the valve is open or closed. If you keep going up, we can now see the pneumatic part off the valve. This is exterior off the pneumatic actuator, as we call it so two different areas. So the body down here, this is completely mechanical indicates up in the middle on and the dramatic section on the top. So that's no Have a look at a cross section and we could see inside. Now what we've actually got is a dire from that's this black area on the top off the springs and see him looking straight at it Now, underneath the dire from we've got a spring. In fact, two springs on below that you go down, got an indicator again on the chef comes down here on DCA necks onto this item, which people refer to as a disc or sometimes a lid on that is going to move up or down, and that is essentially gonna open or close the valve. This type of valve is called a globe fell. You can see from its shape. It shapes slightly like a blow. If you've got a very walt sense of vision on the type of flow valve that it is called a straight flow valve or a zed type valve. Zed referring to the flow coming down here and then go back up and then back out. Obviously we can't do that a moment because the valve is closed. But let's play the animation and we can see what happens when we drain the air from the system. You can see it's moving back up. So what just happened? We're gonna back up again. The tart in this space, This whole compartment above the dire from above the black area, The bottom. This is all full off compressed air. Now, this is gonna be six or seven bar pressure on when we flood the area with compressed air, which is coming through this connection in the middle of the screen we're gonna do, apply the air pressure comes in and pushes the dire from down. What it's actually doing is overcoming the spring tension, and it is compressing the springs. So the compressed air is pushing down bond. Put in those springs on the compression. So when we do that, we are actually the final result is that we're pushing the little the disc down onto an area which they refer to as the seat with C is this area Here is where the lead meets the body. If you have any sort of contamination in this area, the valuable, actually. Leash. So the the sea is very, very important, as is the little bit that sits on it, I assume are a little bit more. Now I'm gonna do I'm gonna do open avowals on. We're gonna drain the air from this entire section. So everything above the black guy from which is normally just a piece of sort of night trial rubber, which is actually quite flexible. I'm gonna drain the air on when I drank beer. The pressure within this area is going to reduce. So let's do that now. And that's what happens when I drained the air. The pressure drops and the springs which were held under compression, are suddenly able then to expand again. And when they expand the results is because the diaphragm is connected to the valve stem. We go down, we can see the valve is now open on the flow of liquid will come down here, back up here and then out that way. That zet flow that we were talking about earlier. That's why it's called type valves. Also a straight vote for straight flu. How and that essentially, how we can control of our how we could make it open or close. What's that again? And you can also watch indicator. Imagine that now we had an oh, where the indicator is pointing out so we only have an over here and down here we would have a C, for example, or maybe without green and red or something like that on that indicates what's visually what the position of the valve is. Okay, the pressure is applied. Pressure is applied. It pushes the diaphragm down. The springs are now under compression. He stem moves down on the stem. Ultimately closes the loop or Bush's disc onto the seats on that closes the valve. So we did. There was, Yeah, I even be compressed there to the diaphragm. Let's have a look now what happens when we drain the air drain year on the springs due to detention or the stored energy that they have, they expand on. They have now opened the valve again. We actually refer to this as a spring open air close. So when people talk about it, they'll say I was spring. Open their clothes, and that means what the default position is is when there is no air valve will leave on. This is quite important concept because a lot of times vows like this. They will have a certain position they should default back to in the event of power loss or a loss of air. The last thing you want when you lose power or your supplies here is that the valves will just stay where they are. Or they switched to a position that is actually worse than if they have stayed where they are. So, for example, maybe you lose power and you want to completely isolate a steam system. Well, if you've lost power on the air drains and it leaves in the open position, steam just flows through the valve. That's the opposite of what you want, Teoh. So what? You'd actually do you change the valve set up that we have here, and you'd make it so that instead of on the losses air, you actually left the valve open, he would say on the loss of air, the valve should return to fully closed. So that's sort of safety position. Obviously, there are different ways to actuate valves. This globe valve is ideal in the open or close position, and that's something that we can do pretty well by controlling the air by making on off, but it would not be so. Ideally, we needed to throttle without, and that means to move it between a position that is not fully open or fully closed. That's what we refer to his front wing, Andi. This type of actuacion would not be ideal physically, quite difficult to gauge the position off the valve using compressed air. It's not impossible, but there are other ways to do which are more reliable, however, for fully opened, fully closed cinematic actuacion that is actuacion with their his ideal. You can also hydraulically actuate evolve like this, and that is actuacion it with liquid. On one of the other options. He might go for a simple hand mechanical actuacion. Or perhaps you would use an electric motor, and you can also vary the position of the valve. In that way,