1.1 This practice covers the designs, sizes, classifications, and construction of enveloped gaskets for severe corrosive applications. The envelope serves as the corrosion resistant member of the composite gasket and is a nonmetallic material such as polytetrafluoroethylene or related materials. The inserts are nonmetallic gasketing materials with or without metal reinforcement. Other types of composite gaskets are covered in Classification F868.

1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.

1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.