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Centrifugal pump | How does a centrifugal pump works in industry sector?

Centrifugal pump is a kind of mechanical equipment that transfers liquid mainly by the energy and centrifugal force generated when the impeller rotates. The working principle of the centrifugal pump is that after the water enters the pump, the impeller rotates at high speed to produce centrifugal action to work. Before starting the sealing ring, we must inject water into the pump casing and suction pipe until the inside is full of water. Then we can start the centrifugal pump. The water will be thrown out of the impeller under the centrifugal action and flow into the pressurized water pipeline of the pump. Centrifugal pump is mainly composed of these parts, including impeller, bearing, pump body, pump shaft, sealing ring, and so on.

  1. The impeller is the most important core part of the centrifugal pump. Because of its high speed, the output force is relatively large. The smooth surface inside the impeller can reduce water loss.

  2. The sliding bearing uses transparent oil as a lubricant.

  3. The pump body is the main body of the water pump. It is mainly used for supporting and fixing.

  4. The function of the pump shaft is to connect the motor with the coupling and transmit the torque of the motor to the impeller, so it is the main component for transferring mechanical energy.

  5. The purpose of the sealing ring is to reduce leakage.

How does a centrifugal pump work?

The centrifugal pump is mainly composed of an impeller, a suction chamber, a discharge pipe, and an ejection chamber (volute). When the prime mover drives the impeller to rotate at a high speed through the shaft, the blades on the impeller will force the fluid to follow the rotation, that is to say, the blades will apply force to the fluid along the direction of its circumferential tangent to increase the pressure energy and kinetic energy of the fluid. Near the outer edge of the impeller has the highest circumferential tangent speed. Therefore, the fluid there also has the highest pressure energy and kinetic energy.

Under the action of inertial centrifugal force and differential pressure force, the fluid will be discharged from the outer edge of the impeller outlet, and the fluid will be transported to the designated destination through the pressure chamber (volute), discharge pipe, and outlet pipe. Besides, under the action of inertial centrifugal force, the fluid will be discharged from the outlet of the impeller, forming a fluid void space in the center of the impeller, which is its low-pressure zone. Under the action of low suction pressure, the fluid passes through the suction chamber from the suction pipe and flows to the central part of the impeller. When the impeller rotates continuously, the fluid will be continuously sucked in by the center of the impeller, and then discharged through the outlet of the outer edge of the impeller, forming the working process of the centrifugal pump to continuously deliver fluid.

Types of centrifugal pumps and their application

According to the number of stages, centrifugal pump can be divided into:

  1. Single Stage: There is only one impeller on the pump shaft. The design of a single impeller is suitable for larger flow, and the increase of pressure head is relatively small.

  2. Multi-Stage: There are two or more impellers on the pump shaft. The total pump head is equal to the sum of the heads produced by N impellers. Multi-stage pumps are suitable for use in situations where a high head is required for discharge. The impellers are connected in series, so each stage increases fluid pressure.

According to the flow type direction through the impeller, centrifugal pump can be divided into:

  1. Axial Flow: Axial flow pumps are liquids that flow parallel to the pump shaft. This type of pump is often used to handle a small pressure head and a large amount of fluid. The most common axial flow pumps are dewatering pumps and water circulation pumps.

  2. Radial Flow: The radial centrifugal pump sucks the liquid into the flange in parallel, and then vertically discharges the liquid, perpendicular to the pump shaft. The radial centrifugal pump can also be used as a high-pressure low-flow pump because it can use a limited flow to increase the pressure at the time of removal. It often appears in the petroleum industry.

  3. Mixed Flow: The mixed flow pump is when the liquid can flow radially or axially. The mixed flow pump is mainly used to handle the high flow of water.

According to the number of suction, centrifugal pump can be divided into:

  1. Single suction: There is only one water inlet on the impeller of a single suction pump. Therefore, when the flow of liquid is large, the single suction pump is not enough, we need to use the double suction pump.

  2. Double suction: There is a water inlet on both sides of the impeller of the double suction pump. Therefore, its flow rate is twice that of a single suction pump relatively. It's like two single suction pumps working back to back.

According to the shaft position, centrifugal pump can be divided into:

  1. Horizontal: The pump shaft is in a horizontal position.

  2. Vertical: The pump shaft is in a vertical position.

According to the type of impeller and casing, centrifugal pump can be divided into:

  1. Volute: When the liquid flows out of the impeller, it will directly enter the pump casing with a spiral shape. The flow resistance in the pipeline is relatively low.

  2. Diffuser: After the liquid comes out of the impeller, the liquid will enter the guide vane set outside it, and then enter the next stage or flow into the outlet pipe. When the area of the guide vane increases, the flow velocity of the guide vane is reduced, thereby increasing the water pressure.

According to the working pressure, centrifugal pump can be divided into:

  1. Low pressure: the pressure is lower than 100 meters of the water column

  2. Medium Pressure: the pressure is between 100 and 650 meters of the water column

  3. High Pressure: The pressure is higher than 650 meters water column

MecHero provides many types of centrifugal pump. If you want to purchase or have any questions about centrifugal pump, you can contact our customer service at 011- 7000 7687 or email to

Photo credit: Pixabay

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