PTFE Envelope/coating Gasket PTFE Envelope gasket consists of asbestos,non-asbestos,rubber etc.cushion material having exposed surface covered with PTFE envelope.Depends on excellent corrosion resistance and compression resilient. it's widely used in strong alkalis,cryogenic fluids,oxygen,chlorine gas and disallowable polluted medium.
The main function of a set of PTFE V-Rings also known as Chevron packing, is to seal the stem of a valve to keep liquid or gas products from leaking into the environment. V-Rings are normally used on ball valves but are used in numerous other valves such as control valves, plug valves, gate valve, and globe valves, use these to serve the same purpose. After a valve has been in service for a duration of time it will begin to experience wear on the internal moving parts. So periodic rebuilding requires the replacement of whats known as the “soft goods” in the valve. Industrial and chemical plants typically do this type of maintenace during there schedulled turn arounds. The valves are sent to valve shops to get the necessary repairs to the valves. Once there at the valve shop the valve is taken apart and a thorough overview of the “soft goods” are analyzed for ware. It is a great value at this point in the process to put new V-Rings in the valve to increase the length of time the valve will remain in service. 4B Plastics makes V-Rings from 3/8″ OD to 8″ OD and can machine custom V-Ring sets to your desired dimensions. Due to 4B Plastic’s years of industrial knowledge with making V-Rings for valves they have determined that the more rings in the stuffing box of a valve equats to tighter seal. The ending result is smaller stack heights and less of a chance of a leaking valve. With 4B Plastic’s custom sizing and express delivery quarantees a better fit and a quicker repair. By doing this 4B Plastics can save valve shops numerous weeks on turn around time therefore getting valve shops what they need to complete the rebuilding of the valve rite the first time with a superior V-Ring set with competitive pricing.
PTFE backup ring are used for static and dynamic applications. It's better used for static sealing applications with corresponding O-ring. The use of PTFE backup ring will help control O-ring extrusion in high pressure applications. PTFE backup rings are compatible with all hydraulic fluids, since they are virtually chemically inert, and also can be used in applications involving elevated operating temperature conditions. In addition, PTFE backup rings can greatly improve O-ring performance and extend service life, even if extrusion does not present a problem.
PTFE's mechanical properties can be enhanced by adding fillers such as glass fibers, carbon, graphite, molybdenum disulphide, and bronze. Generally, filled PTFE's maintain their excellent chemical and high temperature characteristics, while fillers improve mechanical strength, stability, and wear resistance. The properties of 25% glass-filled and 25% carbon-filled PTFE grades are shown below for comparison purposes. There are literally dozens of different filled PTFE products and grades -- too many to be listed here.