PTFE envelope gaskets are still a commonly used method of sealing between flange faces in pipelines, distillation columns, reactor vessels, etc.
A PTFE envelope gasket incorporating an insert of compressible material, combines the chemical resistance of PTFE with the resilience of the selected insert. This combination provides a gasket that us capable of compensating for irregularities, which are often present in flanges, particularly those with a very large diameter.
