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.
| File Size : | 1
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| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 57 |
| Published : | 1999 |
