The leakage comparison between the sealing end cover and the pump body is easy to find and deal with

Generally speaking, the leakage between the overhanging shaft of the shaft sleeve, the sealing end cover and the pump body is easy to find and deal with, but it needs to be investigated in detail, especially when the working medium is liquefied gas or high pressure, toxic and harmful gas, it is relatively difficult. some. Other leaks are intuitively difficult to identify and discriminate. Only on the basis of long-term management and repair practice, can the performance of the leak be investigated, analyzed, and judged before a positive conclusion can be drawn. 1. Analysis and judgment of leakage reasons 1. The device leaks during static testing. After the mechanical seal equipment is debugged, a static test is usually carried out to investigate the leakage. If the leakage amount is small, it is mostly because of the dynamic ring or static ring sealing ring; On the basis of initially investigating the amount of leakage and judging the location of the leakage, manual cranking investigation is carried out. If the leakage amount does not change significantly, the static and dynamic ring seals are in doubt; if there is a significant change in the leakage during cranking, it can be concluded that the dynamic There are doubts about the collision of the static ring; if the leaking medium erupts along the axial direction, the moving ring seal is mostly in doubt, and the leaking medium erupts nearby or leaks from the water cooling hole, and the static ring seal is mostly invalid. In addition, leakage channels can also exist together, but there are usually primary and secondary differences. As long as you investigate in detail and know the layout, you will be able to correctly identify them. 2. Leaks appear during trial work. After the mechanical seal of the pump has passed the static test, the centrifugal force generated by the high-speed rotation during operation will inhibit the leakage of the medium. Therefore, during the trial operation, the leakage of the mechanical seal is basically caused by the damage of the dynamic and static ring conflict pairs after the clearance between the shafts and the failure of the end cover seal. The main factors that cause the failure of the conflicting pair seal are: (1) During operation, due to abnormal phenomena such as slack, cavitation, pressure holding, etc., a large axial force is caused, so that the contact surfaces of the dynamic and static rings are separated; (2) For When the mechanical seal of the equipment is tightened too much, the end face of the conflict pair is severely worn and scratched; (3) The sealing ring of the moving ring is too tight, and the tension spring cannot adjust the axial floating amount of the moving ring; (4) The sealing ring of the static ring is too When the moving ring floats in the axial direction, the static ring is separated from the static ring seat; (5) There are granular substances in the working medium, and people enter the conflicting pair during the operation, and the end faces of the dynamic and static ring seals are detected; (6) Sketch selection If it is wrong, the specific pressure of the sealing end face is low or the cold shrinkage of the sealing material is large. The above phenomenon often occurs in the trial operation, and sometimes can be eliminated by properly adjusting the static ring seat, etc., but most of them need to be disassembled and replaced from scratch. 3. It suddenly leaked during normal operation. A few of the centrifugal pumps that leak suddenly during operation are due to normal wear or have reached the service life, but most of them are caused by large changes in working conditions or improper operation and maintenance. (1) Pumping, cavitation or holding pressure for a long time, resulting in damage to the seal; (2) The actual output of the pump is too small, many medium pumps circulate in the pump, and heat accumulates, causing the medium to vaporize and causing the seal to fail; (3) ) The return flow is too large, causing the bottom of the suction pipe side container (tower, kettle, tank, pool) to rise up and damage the seal; (4) For long-term shutdown, there is no manual cranking when restarting, and the secondary cause of conflict is Adhesion and tearing of the sealing surface; (5) Corrosive, polymeric, and gelatinous substances in the medium increase; (6) The ambient temperature changes sharply; (7) The working conditions are frequently changed or adjusted; Sudden power failure or malfunction, etc. Centrifugal pumps leak suddenly during normal operation. If they are not found in time, they will often become a major accident or loss. Attention must be paid and effective measures must be taken. Company website: https://www.orksealing.com/