The first possibility of water leakage at mechanical seal is the plane wear of dynamic and static rings of mechanical seal. There are six reasons for the formation of the plane wear of the dynamic and static rings of the mechanical seal:
1. The device is too tight. Check the dynamic and static ring plane of the mechanical seal. If there is serious burning phenomenon, black and deep traces on the plane, the sealing rubber becomes hard and loses elasticity. This phenomenon is caused by the over tightening of the device. Handling method: adjust the height of the device. After the impeller device is adjusted, use a screwdriver to pull the spring. The spring has strong tension. When it is released, it will be reset. There is a moving interval of 2-4mm.
2. The device is too loose. Check the dynamic and static ring surfaces of the machine seal. There is a very thin layer of scale on the surface, which can be wiped off. There is no wear on the surface. This is caused by the loss of spring elasticity and poor assembly, or the axial movement of the motor.
3. The water quality is poor with particles. Due to the poor water quality, small particles and high content of hydrochloride in the medium, there are grooves and ring grooves on the plane or surface of the abrasive wear machine seal. Disposal method: improve water pressure or medium, change machine seal.
4. Dry grinding damage caused by water shortage operation. This phenomenon is often seen in the negative pressure at the inlet of the bottom valve type device, the air in the water inlet pipe and the air in the pump cavity. After the self equalizing multi-stage pump is started, the friction of the machine seal will generate high temperature during high-speed operation, which can not be cooled. Check the machine seal, the spring tension is normal, the friction surface is scorched and blackened, and the rubber is hard and cracked. Disposal method: exhaust the air in the passage and pump cavity, and replace the mechanical seal.
5. Cavitation. Cavitation mainly occurs in the heat self balancing multistage pump. Because the medium is hot water and the water temperature is too high to generate steam, the steam body in the pipeline enters the pump cavity, which cannot be removed, resulting in water shortage operation, failure of machine seal dry grinding, cavitation installation of automatic exhaust valve, and replacement of machine seal.