Abstract: A spherical annular seal having a through hole in a center thereof and a partially convex spherical surface portion on an outer surface thereof, wherein an inner peripheral surface of the spherical annular seal defining the through hole is reinforced by a reinforcing member formed of a metal mesh, and a uniform lubricating sliding layer of a lubricating composition containing 70 to 90 wt. % of boron nitride and 10 to 30 wt. % of alumina is formed on a surface of the partially convex spherical surface portion.

Abstract: A spherical annular seal having a through hole in a center thereof and a partially convex spherical surface portion on an outer surface thereof, wherein an inner peripheral surface of the spherical annular seal defining the through hole is reinforced by a reinforcing member formed of a metal mesh, and a uniform lubricating sliding layer of a lubricating composition containing 70 to 90 wt. % of boron nitride and 10 to 30 wt. % of alumina is formed on a surface of the partially convex spherical surface portion.

Abstract: A heat-resistant shift member is disclosed which comprises a fundamental body having substantially a desired configuration and formed of one or more of compressed heat-resistant materials such as expanded graphite with entangled wires being firmly embedded therein, and a shifting surface layer member integrally covering the shifting surface of the fundamental body which is formed of one or more of compressed other heat-resistant materials, such as asbestos as well as one or more of powdered solid lubricant compounds such as metallic sulphide with entangled other metal wires made of copper alloy being firmly embedded therein, whereby both of the metal wires are also partially entangled with each other. There is also disclosed a method for manufacturing the same.

Abstract: A heat-resistant shift member is disclosed which comprises (i) a fundamental body having substantially a desired configuration and formed of one or more of compressed heat-resistant materials such as expanded graphite with entangled wires being firmly embedded therein, and (ii) a shifting surface layer member integrally covering the shifting surface of the fundamental body which is formed of other compressed sheet-like heat-resistant materials such as asbestos, a heat-resistant sheet material made of fibers of asbestos, etc.