PTFE envelope gasket is made of a thickness of 0.5 - 1mm ring gasket, put in the incision core material (Asbestos or rubber sheet , etc.) section for the "Y" or "U"-shaped pad package. The PTFE gasket maintain strong corrosion resistance and have high resilience, excellent sealing performance, Can be applied to petroleum, chemical, power, pharmaceutical, food and other industrial equipment connection flange of the static seal a. dissection cut Y-type have one coating, for the level of flat metal, ceramics and glass sealing surface with good results. Also known as Y-type cross-section of the package pad. Turning into a tube material with 0.8MM-- 1MM thin ring, the center of the thickness from the lateral incision, the incision in the Add core material, incision open hole to within about 1.5 --- 2.0MM. b. folding U-type This gasket coated by machine, the core material is generally compressed Asbestos sheet or rubber plate. Outsourcing for the 0.4-0.5MM thick strip of PTFE film, heat sealing it at both ends in the ring after the package outside of the core material was U-shaped.