Patent attributes
A spherical annular seal member (1) has a seal body (4) in which a heat-resistant material (2) and a reinforcing member (3) made of a metal wire have been compressed to fill meshes of the metal wire net of the reinforcing member (3) with the heat-resistant material (2) such that the heat-resistant material (2) and the reinforcing member (3) are integrally formed in mixed form. The seal body (4) has a cylindrical inner peripheral surface (6) defining a through hole (5); an outer peripheral surface (10) constituted by a partially convex spherical surface (7); and annular end faces (8, 9) respectively provided on a large-diameter side and a small-diameter side of the partially convex spherical surface (7). In the seal body (4), the reinforcing member (3) and the heat-resistant material (2) are respectively contained at a rate of 15 to 80 wt. % and at a rate of 20 to 85 wt. %. The heat-resistant material (2) in the seal body (4) has a density of 1.20 g/cm3 to 2.00 g/cm3.