Abstract: A ring-shaped metal gasket 10 in which a metallic ring 10b is fitted to at least one of two valley portions 11b, 12b in the ring-shaped metal gasket 10a. The metal gasket 10 is free of plastic deformation even if a large compressive load is applied thereto and difficult to undergo fatigue destruction. Even if a difference in pressure between a fluid side to be sealed and a non-fluid side on the opposite side is high, the gasket is hard to damage.

Abstract: The present invention provides a combination metal gasket that is formed by fitting a ring-shaped metal base elastic structure in at least one trough portion of two trough portions of a ring-shaped metal gasket that has an S-shaped longitudinal cross section. The combination metal gasket does not demonstrate the plastic deformation even when a large compressive load is applied and is not likely to be destroyed even when a pressure of a fluid being sealed is high; that is, stable sealing properties are exhibited.

Abstract: To obtain a gasket holding device which is unlikely to slip out of a bolt and facilitates mounting of the bolt thereon, a bolt mounting hole made in a metal plate constituting the gasket holding device is provided with an engaging portion which engages the bolt. This engaging portion is formed by processing part of the metal plate on the bolt mounting hole thinly such that it is elastically deformed and projected in between a crest and a root of the bolt.

Abstract: In order to provide a gasket which can be repeatedly used over a temperature range in which a rubber gasket cannot be used, which does not have any risk of damaging a flange, and which can follow the change of the distance between flanges, a gasket is constructed in such a way that two metallic coned disc springs each of which has a circulation opening for a fluid in a central portion and each of which is formed into a seal surface in which an outer peripheral portion with respect to the circulation opening rises having an arc-like curved surface are combined while being oppositely directed and have outer diameter peripheral edge portions which are welded and fixed so that by tightening flanges, repulsive force of the two coned disc springs concentratedly affects the seal surfaces consisting of the arc-like curved surfaces, and a tight fluid seal is formed between the flange surfaces.

Abstract: In order to provide a ring-shaped metal gasket that can secure a uniform sealing property over the entire surfaces of flanges regardless of the position of a bolt and a nut for tightening a clamp, a ring-shaped metal gasket is composed of an annular main body having a square cross section, a pair of annular arm portions projecting circumferentially outwardly of the annular main body in a bugle state at a predetermined angle, and an annular projecting portion bulging circumferentially inwardly with a height larger than the axial height of the annular main body. The annular projection portion acts as a positioning means. When a flange portion is tightened by a wedge action achieved by tightening a clamp, the pair of annular arm portions are elastically deformed and come into pressure contact with the flange surfaces by the elastic repulsive force thereof.

Abstract: The present invention provides a combination metal gasket that is formed by fitting a ring-shaped metal base elastic structure in at least one trough portion of two trough portions of a ring-shaped metal gasket that has an S-shaped longitudinal cross section. The combination metal gasket does not demonstrate the plastic deformation even when a large compressive load is applied and is not likely to be destroyed even when a pressure of a fluid being sealed is high; that is, stable sealing properties are exhibited.

Abstract: In order to provide a gasket which can be repeatedly used over a temperature range in which a rubber gasket cannot be used, which does not have any risk of damaging a flange, and which can follow the change of the distance between flanges, a gasket is constructed in such a way that two metallic coned disc springs each of which has a circulation opening for a fluid in a central portion and each of which is formed into a seal surface in which an outer peripheral portion with respect to the circulation opening rises having an arc-like curved surface are combined while being oppositely directed and have outer diameter peripheral edge portions which are welded and fixed so that by tightening flanges, repulsive force of the two coned disc springs concentratedly affects the seal surfaces consisting of the arc-like curved surfaces, and a tight fluid seal is formed between the flange surfaces.

Abstract: To obtain a gasket holding device which is unlikely to slip out of a bolt and facilitates mounting of the bolt thereon, a bolt mounting hole made in a metal plate constituting the gasket holding device is provided with an engaging portion which engages the bolt. This engaging portion is formed by processing part of the metal plate on the bolt mounting hole thinly such that it is elastically deformed and projected in between a crest and a root of the bolt.