Abstract: By improving a metal gasket having a corrugated portion which is advantageous in sealing property, a non-asbestos gasket in which the sealing property is further improved is provided. A non-asbestos gasket has a three-layer structured sealing portion S configured by: a core layer 1A which is made of a plate of a metal, and which is formed into a concentric circle-like corrugated shape; and surface layers 2, 3 which are made of expanded graphite, and which are stacked on the front and back faces of the core layer, respectively. In an outer circumferential end of the sealing portion S, the core layer 1A is protruded from the front and back surface layers 2, 3 toward an outer diameter side. In an inner circumferential end of the sealing portion S, the front and back surface layers 2, 3 are protruded from the core layer 1A toward an inner diameter side, thereby covering the core layer 1A.

Abstract: By improving a metal gasket having a corrugated portion which is advantageous in sealing property, a non-asbestos gasket in which the sealing property is further improved is provided. A non-asbestos gasket has a three-layer structured sealing portion S configured by: a core layer 1A which is made of a plate of a metal, and which is formed into a concentric circle-like corrugated shape; and surface layers 2, 3 which are made of expanded graphite, and which are stacked on the front and back faces of the core layer, respectively. In an outer circumferential end of the sealing portion S, the core layer 1A is protruded from the front and back surface layers 2, 3 toward an outer diameter side. In an inner circumferential end of the sealing portion S, the front and back surface layers 2, 3 are protruded from the core layer 1A toward an inner diameter side, thereby covering the core layer 1A.

Abstract: A method of producing a spiral wound gasket for sealing fluid such as a liquid including water and oil, and a gaseous body including vapor and gas and a device for producing the spiral wound gasket. The tip portion of a hoop material is cut and raised thereby forming a checking stepped-portion. The checking stepped-portion is caught by a checking pawl, so as to wind the hoop material around a core drum. After winding the hoop material around the outer periphery of the core drum, at least once, the checking pawl is retracted from the outer periphery of the core drum, thereby separating the checking pawl from the checking stepped-portion. The spiral wound gasket produced by the present invention exhibits an excellent sealing property. Moreover, it also has an excellent durability.