① The inlet water quality of the pump is poor. (High impurity content). ② The faucet strainer or water inlet horn is too close to the sediment or placed in the sediment.

③ Bad conveying medium and improper impeller material selection.

(4) The impeller nut of the water pump is often or for a long time loose, which leads to the impeller loosening and eccentric wear.

⑤ The water pump often works under cavitation conditions, which increases the cavitation damage of the water pump.

Maintenance method of water pump impeller;

① Check the water quality of the pump. According to the inspection, measures such as well washing (air compressor or other machines are recommended) and setting up trash racks are taken to improve the water quality. Ensure that the sediment concentration of water can be effectively reduced (generally, the volume ratio of sediment concentration in well water should not be greater than 0.02%) and impurity content.

(2) Raise or lift the faucet and inlet horn of the water pump to make the sediment leave. Under normal circumstances, it is advisable to leave the bottom hole 1 m or more and not less than 0.5m..

(3) Open the pump body of the water pump and check the clearance of the sealing ring, the installation position and quality of the impeller (whether the positioning key of the impeller moves, whether the locking nut falls off or is loose, and whether the clearance between the impeller and the pump shell meets the requirements, etc.). ), and according to the situation for maintenance, adjustment or replacement. Finally, correctly assemble the water pump as required. When assembling the water pump, be sure to ensure the installation accuracy of the water pump.

(4) Open the pump body of the water pump and check the abrasion and fixation of the impeller. Users need to replace the impeller made of wear-resistant materials to prolong the life of the impeller.

⑤ Eliminate cavitation factors, improve cavitation resistance, and reduce the installation degree of water pump as appropriate (correctly calculate the installation height of water pump).

Protection methods of water pump impeller;

1, correctly determine the water absorption height of the pump, and ensure that the pressure at the inlet of the impeller is not lower than the vaporization pressure.

2. Minimize the head loss in the suction pipe. Because the greater the loss, the more the pressure at the pump inlet drops, and the water is easy to vaporize. Therefore, it is necessary to shorten the length of the suction pipe as much as possible, reduce the accessories on the pipe, make the inner wall of the pipe smooth, and appropriately increase the diameter of the suction pipe.

3. Install the water pump in the well. If cavitation is caused by excessive water absorption, the pump can be installed underground or below the ground, close to the water absorption surface.

4. Use spray to increase the pressure at the inlet.

5, try to make the pump run under rated conditions. If the water pump runs at a speed lower than the rated lift or higher than the rated speed, the flow rate of the water pump will inevitably be higher than the rated flow rate, and the water flow speed at the inlet of the impeller will inevitably increase, and the pressure there will be further reduced. Therefore, it is not allowed to lower the pump head and increase the pump speed at will.

6. Set an inducer at the inlet of the water pump, or use cavitation resistant water pump components.

Water pump impeller is made of cast iron. The blades on the pump impeller play a major role, and the shape and size of the pump impeller are closely related to the performance of the pump. Generally, water pump impellers can be divided into single-suction impellers and double-suction impellers. Single-suction impeller absorbs water unilaterally, and the impeller of small-flow water pump is mostly of this type. Double suction impellers absorb water from both sides, and the impellers of large-flow water pumps all adopt double suction impellers. At present, there are four basic types of water pump impellers: runner type (single runner and double runner), vane type (closed and open), spiral centrifugal type and cyclone type. The impeller of centrifugal pump is generally a closed impeller.