Features 
1.Valve bonnet seal ring is the type of mechanical compression, that is to say it is sealed only by the tightening torque of flanged bolt. 
2.Valve bonnet seal ring is used in 6B flanges with standard flanged connections, it has the face seal with good seal performance, but it should have high accuracy. 
3.Valve bonnet seal ring can be reused in the field in the case of the appearance with no damage. 
4.The hardness of valve bonnet seal ring must be15~20HB lower than the mating flange face hardness. 
5.The seal faces of valve bonnet seal ring, including the bevel faces, shouldn't have the scratches, knock marks, cracks and defects. Its surface roughness shouldn't be larger than Ra1.6.


The gaskets are primarily used in the oil, gas, petrochemical and offshore industries. They are also commonly used on valves, pipe-work assemblies and vessel joints and are used to seal flanged connections subject to high pressures and temperatures.