During the use of the self priming trash pump, the part that is easily damaged is the mechanical seal, which is one of the important components of the self-priming sewage pump. When the mechanical seal of the self priming trash pump is damaged, water leakage will occur when the liquid medium is transported.
The first possibility of water leakage at the mechanical seal is the wear of the dynamic and static rings of the mechanical seal. The reasons for the dynamic and static ring plane wear of the mechanical seal are:
1. The installation is too tight
Observe the plane of the dynamic and static ring of the mechanical seal. If there is severe scorching, the surface becomes black and deep marks, the seal rubber becomes hard and loses its elasticity. This phenomenon is caused by over-tightening.
Handling method: adjust the installation height. After the impeller is installed, pull the spring with a screwdriver. The spring has a strong tension, and it will be reset after it is released. There is a moving distance of 2-4MM.
2. The installation is too loose
Observe the sealing and static ring plane of the machine. There is a thin layer of scale on the surface that can be wiped off. The surface is basically not worn. This is caused by the loss of spring elasticity and poor assembly, or the axial movement of the motor.
3. Poor water quality with particles
Due to poor water quality, containing small particles and high content of hydrochloride in the medium, grooves and ring grooves are formed on the plane of the abrasive wear mechanical seal or on the scratched surface.
Handling method: we can improve the water pressure or medium, and replace the mechanical seal
4. Dry grinding damage caused by lack of water
This phenomenon is more common in the negative pressure at the inlet of the bottom valve installation, there is air in the inlet pipe, and there is air in the pump cavity. After the pump is turned on, the friction of the mechanical seal generates high temperature during high-speed operation, which cannot be cooled. , The friction surface is burnt and blackened, and the rubber is hardened and cracked.
Handling method: exhaust the air in the channel and the pump cavity, and replace the mechanical seal.
Cavitation mainly occurs in hot water pumps. Because the medium is hot water, the water temperature is too high to generate steam, and the steam in the pipeline enters the high place in the pump cavity. This part of the steam cannot be eliminated, resulting in water shortage operation, the mechanical seal dry milling failure, and the automatic discharge Gas valve, it is recommended to install an automatic exhaust valve and replace the mechanical seal.