Abstract: A molded discrete low stress gasket is constructed of restructured filled PTFE for use in corrosive or severe chemical environments under relatively low bolt loads. The gasket has a gasket surface and includes a raised outer sealing ring and a raised inner sealing ring. The gasket may constructed from a restructured filled PTFE material, with the sealing rings deforming at lower pressures than the remaining portions of the gasket.

Abstract: A method of manufacturing a gasket material may comprise inserting a polymer sheet into a press, and pressing the polymer sheet with a mold comprising opposing arrays of protrusions to define interconnected sealing ridges surrounding an array of indentations on each major surface of the polymer sheet. A gasket material may comprise a polymer sheet comprising a first major surface and a second major surface, the second major surface opposing the first major surface. Interconnected sealing ridges may define an array of indentations on the first major surface of the polymer sheet. Additionally, interconnected sealing ridges may define an array of indentations on the second major surface of the polymer sheet, substantially symmetric to the first major surface.

Abstract: A gasket material comprising polytetrafluoroethylene (PTFE) and a thermoplastic polymer have a melting point lower than the melting point of PTFE. Preferred thermoplastic polymers comprise fluorinated thermoplastic polymers, and most preferred fluorinated thermoplastic polymers comprise fluorinated ethylene propylene and perfluoroalkoxy copolymer. The PTFE component preferably comprises full density PTFE, and a filler material may optionally be added. The PTFE component is present in the gasket material in an amount from approximately 50% to less than 100%, based on the total weight of the gasket material, and the thermoplastic polymer is present in an amount from greater than 0% to approximately 20%, based on the total weigh to the gasket material.

Abstract: A molded discrete low stress gasket is constructed of restructured filled PTFE for use in corrosive or severe chemical environments under relatively low bolt loads. The gasket has a gasket surface and includes a raised outer sealing ring and a raised inner sealing ring. The gasket may constructed from a restructured filled PTFE material, with the sealing rings deforming at lower pressures than the remaining portions of the gasket.

Abstract: A gasket material comprising polytetrafluoroethylene (PTFE) and a thermoplastic polymer have a melting point lower than the melting point of PTFE. Preferred thermoplastic polymers comprise fluorinated thermoplastic polymers, and most preferred fluorinated thermoplastic polymers comprise fluorinated ethylene propylene and perfluoroalkoxy copolymer. The PTFE component preferably comprises full density PTFE, and a filler material may optionally be added. The PTFE component is present in the gasket material in an amount from approximately 50% to less than 100%, based on the total weight of the gasket material, and the thermoplastic polymer is present in an amount from greater than 0% to approximately 20%, based on the total weigh to the gasket material.

Abstract: A gasket material comprising polytetrafluoroethylene (PTFE) and a thermoplastic polymer having a melting point lower than the melting point of PTFE. Preferred thermoplastic polymers comprise fluorinated thermoplastic polymers, and most preferred fluorinated thermoplastic polymers comprise fluorinated ethylene propylene and perfluoroalkoxy copolymer. The PTFE component preferably comprises full density PTFE, and a filler material may optionally be added. The PTFE component is present in the gasket material in an amount from approximately 50% to less than 100%, based on the total weight of the gasket material, and the thermoplastic polymer is present in an amount from greater than 0% to approximately 20%, based on the total weight of the gasket material.

Abstract: A gasket material comprising polytetrafluoroethylene (PTFE) and a thermoplastic polymer having a melting point lower than the melting point of PTFE. Preferred thermoplastic polymers comprise fluorinated thermoplastic polymers, and most preferred fluorinated thermoplastic polymers comprise fluorinated ethylene propylene and perfluoroalkoxy copolymer. The PTFE component preferably comprises full density PTFE, and a filler material may optionally be added. The PTFE component is present in the gasket material in an amount from approximately 50% to less than 100%, based on the total weight of the gasket material, and the thermoplastic polymer is present in an amount from greater than 0% to approximately 20%, based on the total weight of the gasket material.

Abstract: The present invention relates to a flexible composite plastic material that can be used to fabricate a variety of mechanical goods such as diaphragms. The composite plastic material comprises a layer of rePTFE and a layer of flexible polymer. The composite plastic material may further comprise a layer of thermoplastic polymer between layers of rePTFE and flexible polymer.

Abstract: A method for welding together filled sintered polytetrafluoroethylene components. The ends of the components to be welded are carefully tapered to form reverse mated surfaces and then assembled in position to be welded. The actual welding step is carried out under heat and pressure followed by cooling under pressure. The process is particularly useful in the fabrication of very large gaskets or other very large planar objects.

Abstract: A highly compressible gasket material is formed by fusing two filled sheets of PTFE containing dispersed microballoons to a central unfilled sheet of PTFE which provides tensile strength to the material. The two unfilled sheets each constitute from 20% to 25% of the overall thickness of the gasket material. This method provides a unitary gasket assembly having an overall compressibility of 45% or more, but the thicker unfilled PTFE central area of the assembly provides excellent recovery characteristics and resistance to creep relaxation.

Abstract: A reinforced composite gasketing material characterized by high strength and dimensional stability, excellent recovery and superior creep relaxation resistance properties and a process for producing such a gasketing material are provided. The composite gasketing material of the present invention is a multiple layer laminate of filled polytetrafluoroethylene (PTFE) and at least one ply of perforated stainless steel. The process of the present invention includes the steps of pressure sintering alternately layered sheets of a PTFE/filler blend and stainless steel by the application of a sequence of intervals of pressures and temperatures selected primarily according to the thickness desired in the finished material and then rapidly cooling the sintered composite under pressure. The resulting gasketing material has the metal layer completely encapsulated by and bonded to the PTFE/filler material.

Abstract: A highly compressible gasket material is formed by fusing two filled sheets of PTFE containing dispersed microballoons to a central unfilled sheet of PTFE which provides tensile strength to the material. The two unfilled sheets each constitute from 20% to 25% of the overall thickness of the gasket material. This method provides a unitary gasket assembly having an overall compressibility of 45% or more, but the thicker unfilled PTFE central area of the assembly provides excellent recovery characteristics and resistance to creep relaxation.