Centrifugal pump

Definition and Principle of 1.

• Definition: Centrifugal pump is a kind of pump equipment that transports liquid through the centrifugal force generated by the rotation of the impeller.
• Principle: When the motor drives the impeller to rotate at a high speed, the liquid is sucked into the center of the pump body, and then is thrown to the outlet of the pump casing under the centrifugal force of the impeller, forming a high-pressure area and discharging through the outlet pipe. At the same time, a low pressure area is formed in the center of the impeller to attract more liquid into the pump body and form a continuous water flow.

2. structure and composition

The centrifugal pump is mainly composed of the following parts:

• Impeller: The core part of the centrifugal pump, with high speed and large output force, is responsible for generating centrifugal force.
• Pump body (pump casing): The main body of the water pump plays a supporting and fixing role and is connected with the bracket for installing the bearing.
• Pump shaft: Connect the coupling with the motor to transmit the torque of the motor to the impeller and transmit mechanical energy.
• Sealing device: Such as sealing ring (leakage reduction ring), stuffing box, etc., used to prevent liquid leakage in the pump and outside air.
• Bearing: Support the pump shaft and reduce the friction when it rotates.
• Axial force balancing device: Used to balance the axial thrust generated by the pressure difference between the two sides of the impeller to prevent the axial movement of the rotor.

3. performance parameters

The performance parameters of centrifugal pump mainly include:

• Flow: The volume or mass of liquid discharged by the pump per unit time, commonly used in units of L/s, m/h, etc.
• lift: The energy increase of the unit mass of liquid from the pump inlet to the pump outlet is commonly expressed by the height of the liquid column (m).
• Power: Including effective power, shaft power and matching power, commonly used in W or kW.
• Efficiency: The ratio of the effective power of the pump to the shaft power indicates the performance of the pump and the amount of energy used by the prime mover.
• Speed: The number of times the pump shaft rotates per minute, in r/min.
• Allowable Suction Vacuum and Allowable NPSH: Indicates the index of the anti-cavitation performance of the centrifugal pump.

4. features and uses

• Features:
  • Simple and compact structure, small footprint and light weight.
  • High-speed operation, transmission structure is simple and easy to install.
  • Suitable for conveying water, sewage, chemical liquid and other media.
  • Large flow, high lift, simple maintenance, smooth operation.
• Use:
  • Widely used in industry, agriculture, construction and chemical industry and other fields.
  • Used for water supply, drainage, cooling, circulation, transportation and other technological processes.
  • It also plays an important role in farmland irrigation, agricultural products processing, fire fighting system and so on.

Precautions for the use of 5.

• Before use, ensure that the pump body is filled with liquid to avoid the phenomenon of "gas binding.
• Regularly check and maintain the pump body, bearings, sealing devices and other components to ensure their normal operation.
• Pay attention to adjust the flow and head of the pump to avoid overload operation.
• After the shutdown in the cold season, the water in the pump body should be drained to prevent freezing and cracking.

To sum up, the centrifugal pump is an efficient and reliable fluid conveying equipment, which has a wide range of application prospects and market demand.