General choice of the metal ring pad iron (soft iron), low-carbon steel, Cr5Mo, 0Cr13, 0Cr18Ni9, 00Cr19Ni10 and other metal materials (its hardness should be lower than the flange material 30 ~ 40HBS) processed into shape for the octagonal cross-section type, an oval or RX-type BX-type metal gasket with a seal from the role of the radial. Its principle is the piece with the cushion inner flange ladder outside the tank (mainly outside the side) contact, and pressed to form the sealing effect.       

  Metal ring mat for use in boilers, tower tank, high pressure valves, manhole covers, window autoclave flange sealing and static sealing junction.