Common general seal damage is: first, hardening (aging). The reason for the leakage of seals is that the material itself is hardened by temperature, when the hardness is too high, the seal can not fill the gap between the parts and the matching parts, it will leak; The second is wear. The wear of seals involves the surface finish, movement speed and transmission media of the matching parts, and different sealing materials adapt to different movement speeds; The third is extrusion: when the seal is under too much pressure will be squeezed out to the metal gap, damage the seal and leakage, this situation involves the hardness of the seal itself and whether the metal gap is too large, if the design, selection, processing or installation is handled improperly, there will be extrusion damage; The fourth is corrosion. The situation is that the seal is softened or even dissolved, because the seal is invaded by the media. An error occurred while selecting materials. Pay special attention if the media contains water or solvents.
Leakage is one of the common faults of mechanical equipment. There are two main reasons for leakage: first, due to the result of mechanical processing, the surface of mechanical products must have a variety of defects and shape and size deviations, so there will inevitably be a gap in the connection of mechanical parts; Second, there is a pressure difference on both sides of the seal, and the working medium will leak through the gap. Reducing or eliminating the gap is the main way to prevent leakage. The sealing of the vacuum system, in addition to the sealing medium leakage directly through the sealing surface, but also consider the following two forms of leakage: leakage. That is, under the action of pressure difference, the leakage of the sealed medium through the capillary tube of the sealing material is called leakage; Spread. That is, under the action of concentration difference, the sealed medium is transferred into diffusion through the material produced by the sealing gap or the capillary tube of the sealing material. The role of sealing is to seal the gap between the joint surface, isolate or cut off the leakage channel, increase the resistance in the leakage channel, or add a small work element in the channel to cause pressure on the leak, and partially offset or completely balance the pressure difference causing the leak to prevent leakage.