Full Description

WRC Bulletin 442 summarizes an extensive program on Polytetrafluoroethylene (PTFE) gaskets. From 1993 to 1995, tests were sponsored by eleven gasket producers and users in an effort to develop a protocol for qualifying the tightness and hot performance of PTFE gaskets based on a measure of their margin of safety against gross leakage and on their mechanical and tightness resistance to extremely high loading. Over two hundred sophisticated tests were performed on twenty-seven PTFE based products including hot blow-out tests at various pressures in various test fixtures and room temperature tightness tests (ROTT tests) including a crush load sequence. These tests define and refine the necessary safety margins on relaxation, gross leak (blow-out) and tightness for these materials. The resulting protocol contains requirements for tests involving hot relaxation, gross leakage (blow-out) resistance, gasket constants and high stress performance (crush). The protocol is intended to accommodate all foreseeable types of PTFE based gasket products and makes use of a special NPS 3 Class 150 fixture which was developed and proven for the hot gross leak aspect of the qualification scheme.

Product Details

Published: 1999 Number of Pages: 57 File Size: 1 file , 1.9 MB