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Sealing gaskets and factors easily affected when purchasing


This issue of non-asbestos board manufacturers will introduce you to the understanding of the function, mechanism of the gasket, the factors that are susceptible to sealing, and the factors that affect the purchase of gaskets. Hope to help you!

The function of the gasket is to prevent the leakage of the sealing medium. The way of leakage can be divided into interface leakage and immersion leakage. The reason for the formation of interface leakage is usually due to the loosening of the pressure between the sealing surfaces, the aging, deformation, corrosion, wear or burning of the sealing surface, and the existence of mechanical vibration under working conditions. Immersion leakage is related to the type of gasket material, production method, nature of the sealing medium, working pressure, temperature and other factors.

Theoretically, it is impossible to completely contact the sealing surface even if the gasket is used, so there are no microscopic channels or gaps. Although these channels are very small, they are still relatively small compared to the molecular volume of the fluid medium. If it is large enough, it is impossible to completely block the fluid at the edge of the sealing surface. There will always be some fluid entering between the sealed touch surfaces, and chaotic fluid dynamics and thermodynamic processes will occur between them.

The main factors that affect the sealing are the following conditions: the appearance of the sealing surface; the contact width of the sealing surface; the nature of the fluid; the fluid temperature; the material of the gasket; the preload applied to the sealing surface; the influence of other external conditions (mainly the system Vibration, connector deformation, deviation of installation direction, etc.). If you want to make the seal reliable, you must carefully consider the above factors, and the quality and selection of the gasket is also very important.

The purchase of gaskets will be affected by the following factors:

The roughness of the contact surface of the part. This has a great impact on the sealing effect, especially when using non-soft gaskets. This is because the roughness of the contact surface of the component is one of the main causes of leakage. Soft gaskets have lower requirements for the roughness of the contact surface of the parts. This is because it is simply deformed and can block the leakage path formed by the contact surfaces of the two parts in contact with each other, and then ensures a good sealing effect.

The contact surface condition of the part. The contact surface conditions of the parts are different, and the gaskets to be used are also different. For example, the contact surface of lubricated parts should generally be low-pressure, soft and thin gaskets; under high-pressure operating conditions, when the strength of the parts is met, thick and soft gaskets should be used instead of metal washers.

The contact surface of ferrous metal parts should use copper metal washers instead of aluminum metal washers to prevent ferrous metal parts from being damaged by electric corrosion.