Dual density sanitary pipe gasket
US5971399A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | May 5, 1997 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | May 5, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16J15/104
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A sanitary-pipe gasket includes an annular disk portion of predetermined thickness, and a projecting portion which is provided concentrically with the annular disk portion on each of the upper and lower surfaces of the annular disk portion. The annular disk portion and the projecting portion of the sanitary-pipe gasket are integrally formed of porous PTFE such that the density of the annular portion ranges from 1.0 to 1.9 g/cm.sup.3 and the density of the projecting portion ranges from 0.3 to 1.8 g/cm.sup.3. The gasket is produced by disposing a porous PTFE sheet of 0.3 to 1.4 g/cm.sup.3 density and 1 to 10 mm thickness in a mold, and applying pressure perpendicular to the sheet at room temperature or with heating. The density of the gasket adjacent the planar surfaces and a peripheral edge surface is substantially higher than the density further inward of these surfaces, and the density adjacent the peripheral edge surface is sufficient to seal the peripheral edge surface against radial flow past the gasket when installed between a pair of flanges.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.