Differences of Self priming Centrifugal Pumps

In order to better discharge the gas in the moisture absorption pipe and generate a certain vacuum value during the operation of the general centrifugal pump, the exhaust pipe must be used. For small pumps, the pump casing and water inlet must be filled with water before starting. In order to better avoid the jump of water injection, the bottom end of the water inlet is equipped with a unilateral pump bottom valve that opens when the water flows upward and closes when it flows downward; Generally, large centrifugal pumps with water seepage specifications above 300 mm are not equipped with bottom valve of water pump, but only use professional vacuum equipment to vacuum drinking water. There is no doubt that the startup of the feed pump will cause inconvenience, resulting in waste.
Principle: The centrifugal pump is operated by the centrifugal movement of water generated by the rotation of the impeller. Before starting the water pump, be sure to fill the pump housing and the moisture absorption pipe with water, and then start the motor to make the pump shaft push the impeller and water for high-speed running fitness exercise. The water produces centrifugal movement and is thrown to the edge of the impeller. The water is injected into the pressurized tap water pipeline of the pump through the gate of the volute pump housing.
Structure: The centrifugal pump operates by the centrifugal movement of water generated by the rotation of the impeller. The main structure of centrifugal pump is composed of 61 parts, namely impeller, pump housing, pump shaft, rolling bearing, sealing ring and ferrule joint.
The structural type of self-priming centrifugal pump has been improved to get rid of the shortcomings of general pipeline centrifugal pump. Self priming centrifugal pump has the advantage that the pump casing is of double volute structure. The detergent port is located on the edge of the pump impeller, and there is a large capacity vapor liquid separation chamber on the liquid outlet. Other structures are similar to single pole single suction centrifugal pumps, including sealing rings, mechanical seals, shafts and rolling bearings. When the self-priming pump is started for the first time during operation, the water diversion channel must be introduced into the pump casing, and the introduction amount can exceed the pump centerline in the pump casing. After that, the fully automatic suction pipe can be started at any time and anywhere, without introducing the diversion canal, so the application is more convenient than the pipeline centrifugal pump.
Principle: The design principle of self-priming pump is to fill the pump casing with water (or the pump casing itself has water) before starting the pump. After startup, the impeller runs at a high speed to make the water in the impeller channel flow to the volute. At this time, the channel generates a vacuum pump to open the seepage check valve. The gas in the suction pipe enters the pump and reaches the edge through the impeller channel.
Structure: Self priming centrifugal pump is a kind of centrifugal pump, but compared with centrifugal pump, its big difference is that it has "self priming" characteristics. The main structure of self-priming pump is composed of suction chamber, liquid storage chamber, scroll chamber, liquid collection hole, vapor liquid separation chamber, etc.

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