Self Priming Centrifugal Pumps

Self priming centrifugal pumps are special type of centrifugal pump. A self priming centrifugal pump refers to a centrifugal pump that does not require priming before starting for the first time and does not require priming when starting again. It can automatically extract the gas in the suction pipe and deliver liquid normally. The pump has the advantages of compact structure, easy operation, smooth operation, easy maintenance, high efficiency, long life, and strong self priming ability.

Working principle
The working principle of self priming centrifugal pumps mainly depends on its special design. In the pump body, there is a suction chamber, and the suction pipe is above the center line of the impeller. After stopping the pump, some liquid remains in the suction chamber. When the pump is started again, the liquid remaining in the suction chamber circulates in the pump, sucking the gas in the suction line into the impeller. After mixing in the impeller (internal mixing type) or at the impeller outlet (external mixing type), the gas and liquid enter the gas-liquid separation chamber added at the outlet to separate the gas and liquid. The gas is discharged from the pump and the liquid returns to the suction chamber until the suction pipe is filled with liquid to achieve normal transportation.

Basic structure
The self priming centrifugal pumps mainly consists of the following six parts:

Impeller:
It's the main part of a self priming centrifugal pump. The faster it spins, the more power it has. The inner and outer surfaces of the impeller need to be smooth. This helps to reduce the friction loss when water flows through.
Pump Body:
Also called the pump casing, it's the main part of the water pump. It supports and holds everything in place, and is connected to the bracket where the bearings are installed.
Pump Shaft:
It's connected to the motor through a coupling. It transfers the motor's turning force (torque) to the impeller. It's the main part for passing on mechanical energy.
Bearing:
It's a part that fits around the pump shaft to support it. There are two types: rolling bearings and sliding bearings.
Sealing ring:
Also known as leakage reduction ring, installed at the junction between the inner edge of the pump casing and the impeller's external aid, used to increase return flow resistance, reduce internal leakage, and extend the service life of the impeller and pump casing. The sealing gap should be kept between 0.25~1.10mm.
Stuffing box
Mainly composed of stuffing, water seal ring, stuffing barrel, stuffing gland, and water seal tube. It is used to close the gap between the pump casing and the pump shaft to prevent the water in the pump from flowing to the outside and prevent outside air from entering the pump.

Application Scope
Self priming centrifugal pumps are widely used in many industries because of their high efficiency and convenience. Including but not limited to agricultural irrigation, garden sprinkler irrigation, fire protection systems, building construction, chemical industry, petroleum, pharmaceuticals, mining, paper making, fiber, pulp, textiles, food, power plants and municipal sewage projects, etc.

Welcome to contact with us for more information
Email: cristine@deponpump.cn
Whatsapp: +86 150 7549 4342
Sales manager:Cristine Guan