• The chemical resistance of rubber gaskets and compressed fibre gaskets can be considerably improved by inserting them into a PTFE-envelope. Because of the good adaptability of PTFE, particularly low sealing rates can be achieved with adequate gasket pressure.
• By choosing particularly suitable styles of PTFE with low cold-flow (e.g. Dyneon TFM 1600),and by using special combinations of insert materials, e.g. corrugated metal rings with graphite cover on both sides, even the most demanding sealing problems (e.g. enamelled flanges or applications with serious thermal cycling)can be solved.Material properties
• The envelope is made from 100% pure virginal PTFE.
• By adding 2%of conductive pigment to the PTFE-resin, or by adding earth connection points to the corrugated metal ring, electrical conductivity can be assured.
• For use with diffusing or strongly toxic media (e.g. chlorine gas), special PTFE-envelopes with 0,75mm thick material and reinforced inner diameter acting as diffusion barrier, can be produced.
Applications:
PTFE-envelope gaskets are being widely used in the food and beverage industry, as well as in the pharmaceutical and chemical industry, because of their anti-adhesive properties and the hysiological harmlessness of PTFE.They can be removed quickly and easily - and without residue - from the flange faces, new gaskets are installed in no time.
PTFE -Envelope-Corrugated Gasket
The gaskets for glass-lined equipment and pipelines is consisting of asbestos-free insert, stainless corrugated ring and pure PTFE envelope. There is two kind of inserts, The fiber plate and the graphite plate.The RD630、RD631and RD632 shapes are offered to envelope cover of nozzle gaskets. it has good compressibility to give safe and reliable sealing without risk to the glassed surfaces.