Seal part

Abstract

A seal part having a base material, a porous coating layer formed by flame spraying a hard material on a seal surface of the base material, and a lubricating film containing one or more types of materials selected from silver, gold, and tin and a gold-cobalt alloy on the porous coating layer. The seal part of the present invention has superior durability and sealability and further a long life and high reliability even when used in a high temperature (for example 400° C. or more, in particular 400 to 600° C.) and high pressure (for example 2 MPa or more) environment.

1 . A gasket comprising:
 a seal part, the seal part comprising:
 a base material, 
 a porous coating layer formed by flame spraying a hard material on a seal surface of said base material, and 
 a lubricating film containing one or more types of materials selected from silver, gold, and tin and a gold-cobalt alloy on said porous coating layer, 
   wherein the gasket has an E-shaped or W-shaped cross-sectional shape.   
     
     
         2 . The gasket as set forth in  claim 1 , wherein said porous coating layer is comprised of a flame spraying material containing one or more types of material selected from a nickel based alloy, cobalt based alloy, chromium carbide, and tungsten carbide. 
     
     
         3 . The gasket as set forth in  claim 2 , wherein the thickness of said porous coating layer is 10 to 200 μm and the thickness of said lubricating film is 1 to 50 pm. 
     
     
         4 . The gasket as set forth in  claim 3 , wherein said base material is a base material comprised of a nickel based alloy. 
     
     
         5 . The gasket as set forth in  claim 4 , wherein said seal part is used in a range of temperature of 400 to 600° C. 
     
     
         6 . The gasket as set forth in  claim 4 , wherein said seal part is a tubular seal part having a flexible part flexibly deformable in a radial direction, and said flexible part has a seal surface. 
     
     
         7 . A tube seal having a tubular body, the gasket, and the seal part as set forth in  claim 6 .