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What Is the Difference between Centrifugal Pumps and Self-Priming Pumps?

Centrifugal pump or self-priming pump? It depends on where it is used and cannot be determined solely. A self-priming pump may be a centrifugal pump, but a centrifugal pump is not necessarily a self-priming pump. The self-priming centrifugal pump needs to inject a certain amount of starting circulating water into the pump body for the first start-up; the centrifugal pump requires the water to be filled in the inlet pipe and pump body at the same time or use an auxiliary device to pump the inlet pipe.

The composition of centrifugal pumps and self-priming pumps is different

The basic structure of a centrifugal pump is composed of six parts: impeller, pump body, pump shaft, bearing, sealing ring, and filled box, while a self-priming pump is composed of suction chamber, liquid storage chamber, vortex chamber, liquid return hole, and gas-liquid separation chamber, etc.

The advantages of centrifugal pumps and self-priming pumps are different

The structure of the self priming pumps is compact, easy to operate, runs smoothly, easy to maintain, has high efficiency, long service life, and strong self-priming ability. On the other hand, the advantages of centrifugal pumps china are compact structure, wide range of flow and lift, more suitable for mildly corrosive liquids, various control options, uniform flow rate, stable operation, small vibration, no need for special shock-absorbing foundation, and low equipment installation and maintenance costs.

The working principles of centrifugal pumps and self-priming pumps are different

The working principle of the self-priming pump is to fill the pump shell with water (or the pump shell itself will hold water) before starting. After starting, the high-speed rotation of the impeller makes the water in the impeller channel flow toward the volute. At this time, the inlet forms a vacuum, and the check valve opens, so that the air in the suction pipe enters the pump and reaches the outer edge through the impeller channel. The centrifugal pump relies on the rotation of the impeller to make the water undergo centrifugal motion to work.

The difference between a self-priming pump and a centrifugal pump is that the self-priming pump can suck the liquid within 5 meters without installing a bottom valve and filling the pump chamber with water for the first time. After the first use, the self-priming pump can be started directly without adding water. This is the characteristic of the self-priming pump. Self-priming pumps can also be used in environments where centrifugal pumps are used, and they can be used even when the liquid level is higher than that of the self-priming pump. However, the centrifugal pump can only play a role in pressure transmission and does not have the function of a self-priming pump. It can only be used in a pipeline-boosting environment. If you want to achieve the function of a self-priming pump, you must install a bottom valve at the bottom of the water tank and fill the pump and inlet pipeline with liquid each time you use it to suck up the liquid.