Spherical annular seal member and method of manufacturing the same

Abstract

A spherical annular seal member which has a cylindrical inner surface defining a through hole in a central portion thereof as well as an outer surface formed in the shape of a partially convex spherical surface, and which is used particularly in an exhaust pipe joint, includes: a reinforcing member made from a compressed metal wire net; a heat-resistant material filling meshes of the reinforcing member and compressed in such a manner as to be formed integrally with the reinforcing member in mixed form, the heat-resistant material and the reinforcing member being provided as principal components in an interior portion of the spherical annular seal member which extends from the cylindrical inner surface to a vicinity of the outer surface formed in the shape of the partially convex spherical surface, aluminum phosphate being also formed integrally with the reinforcing member and the heat-resistant material in mixed form; a sliding layer formed of a lubricating composition which is constituted of boron nitride and at least one of alumina and silica, the sliding layer being disposed as a surface layer of the spherical annular seal member which extends from the vicinity of the outer surface formed in the shape of the partially convex spherical surface to the outer surface formed in the shape of the partially convex spherical surface; and a reinforcing member disposed in the sliding layer and made from a compressed metal wire net formed integrally with the sliding layer in mixed form, wherein the outer surface formed in the shape of the partially convex spherical surface where the sliding layer and the reinforcing member made from the metal wire net formed integrally with the sliding layer in mixed form are exposed is formed into a smooth surface.