Cause analysis and treatment measures of mechanical seal leakage1

Cause analysis and treatment measures of mechanical seal leakage

In centrifugal pumps and reactors, the seal between the rotating pump shaft and the stationary housing is called a shaft seal device. At present, centrifugal pumps and reactors are commonly used for seals and mechanical seals. Mechanical seals are widely used because of their low leakage, long service life, low power loss, no frequent maintenance and low environmental impact. Mechanical seals are complex to manufacture and have high precision requirements. During the operation, the inspectors are required to find the problem in time and solve it as soon as possible to prolong the service life of the mechanical seal. 1. Mechanical seal vibrates, generates heat, and emits smoke. 1. The end face is greater than the pressure. Treatment measures: (1) Adjust the position of the moving ring base to reduce the specific pressure of the end face; (2) Replace the mechanical seal spring to reduce the end face specific pressure. 2. End surface roughness of dynamic and static rings Treatment measures: Grind the dynamic and static rings on the grinding platform to improve the end surface finish. 3. Insufficient cooling and flushing Treatment measures: Regularly clean the flushing pipeline and keep it well lubricated. Second, the mechanical seal end face leakage 1. The end faces of the moving ring and the fixed ring are not flat. Treatment: Adjust the bottom of the movable ring to the position perpendicular to the pump shaft. Whether the static ring is in place. 2. The adhesion of impurities and solidified medium makes the moving ring not free to float. Treatment: Check the flushing pipe filter to prevent impurities from clogging the sealing element. 3. The spring force is not enough, resulting in insufficient specific pressure. Treatment: Adjust the position of the moving ring base to increase the spring force. 4. The end cap is not perpendicular to the shaft. Treatment: Adjust the end cap perpendicular to the shaft. 5. Poor floating of dynamic and static rings. Treatment measures: Improve the elasticity of the sealing ring, and appropriately increase the clearance between the dynamic ring and the fixed ring and the pump shaft. 3. Axial leakage of mechanical seal 1. The seal ring and the shaft are too loose or too tight. Handling: Choose the right seal to ensure the right size. 2. The sealing material is too soft, too hard or corrosion-resistant, and the heat resistance is not easy to handle: choose the appropriate sealing material 3. Sealing and curling of the sealing ring during installation: the interference of the sealing ring and the shaft should be correctly and should be installed with care.