Roughness of contact surface of parts. This has a great impact on the sealing effect, especially when non-soft gaskets are selected. This is because the roughness of the contact surface of parts is one of the main reasons for leakage. Soft gaskets for parts contact surface roughness demand is low, this is because of its simple deformation, can block the two parts contact surface micro-convex body contact with each other and constitute the leakage channel, and then ensure the outstanding sealing effect.
State of contact surface of parts. Parts contact surface condition is not the same, the need to use the gasket is not the same. For example: lubrication parts contact surface, generally should choose low pressure, soft and thin gasket; Under the condition of high pressure operation, when the strength of parts meets, thick and soft gaskets should be used instead of metal gaskets.
Copper metal gasket should be used for the contact surface of black metal parts, rather than aluminum metal gasket, to avoid electrical corrosion damage of black metal parts.
The hardness of connecting surface and sealing layer of parts is poor. The intention of using the gasket is to make the gasket elastic or plastic deformation, in order to fill the small uneven parts of the contact surface, prevent the leakage of the flow medium attack. Therefore, the hardness of the sealing pad should be lower than the hardness of the parts. The greater the difference between the two, the simpler the sealing is.