Measures to Improve Self-priming Performance and Self-priming Capability of Self-priming Pumps

Measures to improve the self-priming performance of self-priming pumps

Increase the maximum circumferential velocity of the impeller outlet and the width of the impeller blade outlet. The maximum circumferential velocity of the impeller outlet can be increased by increasing the impeller speed directly. However, ensuring an excessively large increase in the maximum circumferential velocity of the impeller outlet and the width of the impeller blade outlet will change the basic performance parameters of the pump, such as flow rate and head. Therefore, it is necessary to moderately increase the maximum circumferential velocity of the impeller outlet and the width of the impeller blade outlet under the premise that the flow rate and head of the pump meet the requirements.

Relationship between water storage capacity and self-priming performance: when the water storage capacity increases, the self-priming height of the pump is significantly improved. However, when the water discharge is too large, the gas discharge process slows down, which increases the self-priming time. Therefore, when the self-priming height requirement is high but the self-priming time requirement is not strict, the water storage capacity of the self-priming pump can be increased by increasing the volume of the liquid storage chamber. However, when the self-priming time requirement is strict, the size of the liquid storage chamber should be reasonably determined.

Relationship between backflow hole area, self-priming time and self-priming height: within the critical backflow hole area, when the backflow hole area increases, the self-priming time decreases, and the self-priming height decreases accordingly. Therefore, when the self-priming time requirement is strict and the self-priming height requirement is not high for self priming pumps manufacturers, the area of the backflow hole can be appropriately increased, and vice versa.

Setting up an acceleration device for gas-liquid separation can accelerate gas-liquid separation, which can shorten the self-priming time. The simplest gas-liquid separation acceleration device is to add a baffle in the gas-liquid separation chamber. Adding a baffle in the gas-liquid separation chamber has almost no effect on the self-priming height. Therefore, if the structure permits, a baffle should be set up in the gas-liquid separation chamber to accelerate gas-liquid separation and shorten the self-priming time.

Improving the self-priming capacity of self-priming pumps

The end of the suction pipe of a self-priming sewage pump is equipped with a suction bottom valve. The suction bottom valve is actually a check valve, which ensures that the water flow can only enter the suction pipe from the water tank and cannot flow back. Therefore, even if the water level in the suction pipe is higher than the working water level of the water tank, the water in the suction pipe will not flow into the water tank due to the effect of the suction bottom valve, and the suction pipe will always be filled with water, ensuring that the water pump can start automatically and quickly.

The reliability of this suction method is affected by the quality of the suction bottom valve. For example, if the valve does not close tightly and leaks water, the water in the suction pipe will slowly flow into the water tank. After a long time, there will be no water in the suction pipe, which will require manual water filling when the water pump starts.

Reduce the number of bends in the inlet pipe, the height difference, and the horizontal distance of the self-priming sewage pump inlet pipe.

Setting up a suction tank in front of the pump. This method requires setting up a suction tank on the suction pipe of the water pump. Before the water pump runs for the first time, the tank should be manually filled with water. After the first run stops, because the water level in the inlet pipe of the suction tank is higher than the water level inside the tank, even if the water level in the water tank is lower than the water level in the tank, the water in the tank will not flow back into the water tank. Therefore, some water can be stored in the suction tank. Moreover, because the height of the outlet pipe of the suction tank (i.e., the suction pipe of the water pump) is lower than the water level inside the pipe, the suction pipe of the water pump can be filled with water, ensuring that the water pump can automatically start quickly. When the water pump runs again, the water in the tank is sucked away by the water pump, and a negative pressure is generated in the tank, which causes the water in the water tank to replenish the suction tank under atmospheric pressure.

Setting up a vacuum pump on the suction pipe of the self-priming sewage pump to fill the suction pipe of the water pump with water before the water pumpstarts. This suction method requires a sophisticated automatic control system to ensure normal operation.