We rely on the functioning of valves for various processes to ensure their safety and maximize efficiency. The reliability of a valve is directly proportional to the quality of the seal.
Any given procedure must be able to accommodate the specific operating circumstances that the valve must tolerate. These kinds of circumstances include the presence of components that are either caustic, extremely hot, or high in pressure. The seal must withstand the wear and tear that comes with repeated opening and closing.
The valve PTFE seats are critical to maintaining the integrity of the seal. Because of this, you need to pick one suited for the process’s circumstances. Using this post tutorial, you will learn how to choose which valve seat is appropriate for a certain procedure.
What Exactly Is A “Seat” In A Valve?
When a valve is in the closed position, the moving part of the valve will rest on the valve seat when the valve is in this position. In applications using valves, the disc is positioned to firmly rest on the seat to close and seal the valve.
Even when subjected to the temperature, frictional, and impact loads of a process, seats are constructed to maintain the integrity of the seal.
Choosing the Right Valve Seat Type
There are many diverse applications for valves. Thus, we have various varieties. The application parameters, including temperature, pressure, and the kind of media, all have a role in determining the sort of valve seal that is employed.
Refer to the manufacturer’s published specifications for more information regarding the maximum allowable pressure and temperature that a valve may withstand.
Below are some major types of valve seat types:
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EPDM (E)
Ethylene Propylene Diene Monomer is called EPT, Nordel, and EPR. EPDM is the abbreviation for this material. This elastomer can withstand the corrosive effects of alkaline and acidic substances. It is also resistant to tearing and can withstand the effects of ozone and the elements of nature.
EPDM is an excellent choice for applications requiring water resistance, alcohols, bleach, glycols, ketones, esters, phosphate, and other alkaline solutions.
The temperature rating range for EPDM is between -225 and -30 degrees Fahrenheit.
In the HVAC industry, EPDM is used extensively. However, EPDM is not an appropriate material for use in applications that require lines carrying compressed air that contain petroleum-based oils, chlorinated hydrocarbons, hydrocarbon solvents or oils, turpentine, or other such substances.
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BUNA-N (B)
Nitrile, also known as BUNA-N, is a synthetic rubber copolymer made of acrylonitrile (ACN) and butadiene. Nitrile is also known as nitrile. This type of rubber is a popular elastomer choice in the seal business, such as those used in pond filter systems.
This is because it is resistant to abrasion, has high tensile strength, and has a low compression set.
Hydraulic fluids, petroleum-based oils, water, alcohols, acids, fuels, silicone greases, and other substances pose little to no threat to BUNA durability.
On the other hand, the feature that gives it its strength also gives it its inflexibility. The BUNA temperature rating is 0 degrees Fahrenheit to 180 degrees Fahrenheit, and it is heat resistant up to 225 degrees Fahrenheit.
There are a few applications in the automobile industry for this material. However, BUNA-N should not be used in applications containing acetones, ketones, nitro hydrocarbons, chlorinated hydrocarbons, or ozone since it is inappropriate for those substances.
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PTFE (P)
Teflon is an acronym for the phrase polytetrafluoroethylene, which is sometimes known as PTFE. Teflon is a type of fluoropolymer. This fluoroplastic thermoplastic material provides minimal friction, chemical resistance, and fire resistance in addition to its other desirable properties.
Teflon is utilized in the manufacturing process of some resiliently seated ball valves by many top ball valve factories.
PTFE is a substance used in various applications, including processing chemicals and the oil and gas industry. Because of its insulating properties, it is suitable for usage in various electrical contexts.
On the other hand, it should not be utilized in settings with significant pressure. The PTFE temperature rating varies from -150 degrees Fahrenheit to 400 degrees Fahrenheit.
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VITON (V)
DuPont’s fluorocarbon elastomer is known by its registered trademark name, VITON, and the name is a registered trademark. The brand name for this particular material produced by 3M is Flourel. This elastomer can withstand high temperatures as well as chemicals.
VITON is unaffected by the concentration or concentration level of mineral acids or hydrocarbon products that they come in contact with. The temperature rating for VITON spans from -20 degrees Fahrenheit to 300 degrees Fahrenheit.
Conclusion
Even though valves have been around for a long time and make up a significant amount of our industries, they still demand careful attention to detail and a grasp of the applications into which they will be fitted.
When it comes to designing and developing the ideal seat for a certain application, manufacturers benefit from having a wide range of materials from which to pick.
Which sort of valve seat is ideal for your running process?
Even while some valves may look nearly identical to one another, there are important differences between them. Consult an experienced professional if you want accurate valve seat specifications.
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