1. Leakage caused by the flatness damage of sealing surface
Most of the flatness damage of the sealing surface is caused by uneven slip marks and face cut marks. The cause may be the deformation or damage of the sealing box and mixer head of the pump, or the uneven tightening force of the bolts, which results in the deformation of the sealing surface of the static ring and it finally causes the leakage. It is also possible that the shape of the sealing surface changes due to the change of temperature and the existence of thermal expansion difference of the sliding parts during hot installation. As a result, the leakproofness will also be damaged, leading to leakage problems.
2. Leakage caused by lubricity damage of sealing surface
The lubricity of the end face seal is also very important. In addition to the sealing function of the liquid film on the end face, it also depends on the function of lubrication to complete the normal operation. Once the liquid film on the end surface is damaged, it will cause instant wear and roughness of the thousand friction sealing surface, and even some hard materials will produce cracks and other serious phenomena. When the temperature of the sliding friction surface suddenly rises, if the heat accumulation can not be removed immediately, it will cause the evaporation of the sealing liquid, the disappearance of the lubricating film, and then lead to the occurrence of dry friction phenomenon. Dry friction is easy to damage the sealing surface and it buries a lot of hidden dangers of leakage.
3. Leakage caused by action damage
The moving and static rings of mechanical seal device rotate with the shaft all the time, and they repeat the same movement frequently. This repetitive movement will not only change the seal face but also increase the axial movement of the device, and it gradually reduce the accuracy of mechanical seal. In this way, in the long run, all parts of the device will be damaged or even deformed, thus losing the follow-up performance, leading to leakage of the seal.
4. The leakage caused by the superposition of many factors
The leakage is sometimes caused by the superposition of many factors, such as dry friction, poor sliding, deformation of sliding ring and flatness deformation, which is easy to cause the leakage phenomenon. Many of these reasons are caused by excessive fatigue, uneven pressure and liquid film damage. Therefore, the correct installation and maintenance of mechanical seal cleanliness is very important, which can better eliminate hidden dangers with a good cooling effect.