There is now a wide range of PTFE products to choose from, in the industrial seal market in today's world. The product has evolved dramatically since the late 1960s, moving from virgin, commercial-grade PTFE to current offerings, such as what is described as calendered or restructured filled PTFE sheet. PTFE has many advantages, the two most notable being its exceptional properties. chemical resistance, as only a few chemicals will attack the polymer and can withstand temperatures up to 260C (500F). However, the product has a significant weakness as it exhibits creep and/or flow characteristics when cold, under compressive loads, thereby affecting the performance of the joint, as frequent retightening is required. The fact is that most PTFE users are unaware that several different materials can be used successfully for the same application. The question to ask is which product is right for your application. There are different processes in the manufacture of PTFE sheets, involving sintering the PTFE into billet form and then cutting it into a sheet, or...