All Pumps Machinery Company Limited.

Factors that affect the performance of self-priming centrifugal pumps

The self-priming centrifugal pump achieves one-time drainage and lifelong self-priming through the water storage chamber, utilizing the principle of air pressure. The main factors affecting the performance of the self-priming centrifugal pump can be summarized in the following six aspects:

  1. Determination of liquid storage volume and height: The liquid storage volume should be at least half of the pump's design flow in seconds, and the liquid storage height should be approximately equal to the radius of the impeller.

  2. Determination of gas-liquid separation chamber volume and outlet height: The optimal volume for the gas-liquid separation chamber is equal to or slightly larger than the liquid storage volume, and the outlet height of the pump body can be determined based on the volume of the liquid storage and gas-liquid separation chamber.

  3. Determination of liquid flow rate in the discharge chamber: The flow rate of the liquid in the discharge chamber of the self-priming centrifugal pump is usually 80%-90% of the liquid flow rate in the discharge chamber of a general centrifugal pump.

  4. Determination of the gap between the compartment tongue and impeller: The gap between the tongue and impeller in the upper discharge chamber has a significant influence on the self-priming performance, and is usually designed by external mixing.

  5. Turning of the rear cover plate of the impeller: The amount of turning should not be too large, as it may significantly reduce the head and efficiency of the pump.

  6. Area of the return hole: The area of the return hole has a great influence on the self-priming performance. When determining the area, both self-priming time and self-priming height should be considered comprehensively.