Patent ID: 8991831
Filing Date: 2015-03-31
Classification: F01N,F16J,F16L

Abstract:
1. A spherical annular seal member characterized by comprising: a spherical annular base member defined by a cylindrical inner surface, a partially convex spherical surface, and large- and small-diameter side annular end faces of said partially convex spherical surface; and an outer layer formed integrally on said partially convex spherical surface of said spherical annular base member, wherein said spherical annular base member includes a reinforcing member made from a metal wire net and a heat-resistant material containing expanded graphite and compressed in such a manner as to fill meshes of the metal wire net of said reinforcing member and to be integrated with said reinforcing member in mixed form, and said outer layer is comprised of a base layer which includes a reinforcing member made from a metal wire net and compressed and a heat-resistant material containing expanded graphite, compressed in such a manner as to fill meshes of the metal wire net of said reinforcing member and to be tightly pressure bonded to said reinforcing member, and having a surface which forms an outer-layer intermediate layer surface together with a surface of said reinforcing member, said base layer being formed integrally with said partial convex spherical surface, and of a heated sliding layer constituted by a molten fluororesin composition which is integrally adhered to and formed on said base layer at said outer-layer intermediate layer surface and contains at least a molten fluororesin, a surface of said outer layer exposed to an outside being constituted by a smooth surface of said heated sliding layer, and wherein said molten fluororesin is constituted by a tetrafluoroethylene-hexafluoropropylene copolymer (FEP).