Centrifugal pump is a very common type of pump, which is defined as a pump that uses the centrifugal force generated by the rotation of the impeller to transport liquid.
Principle of centrifugal pump
Centrifugal pump is the use of impeller rotation to make the water centrifugal movement to work. Before the pump is started, the pump shell and the suction tube must be filled with water, and then the motor is started, so that the pump shaft drives the impeller and water to do high-speed rotating movement, and the water has centrifugal movement, is thrown to the outer edge of the impeller, and flows into the pressure water pipe of the pump through the flow channel of the spiral pump shell.
Composition of centrifugal pump
Centrifugal pump is mainly composed of pump shell, impeller, pump shaft, pump frame, packing and so on.
The impeller is the core part of the centrifugal pump, its speed is higher than the force, the blade on the impeller plays the main role, the impeller should pass the static balance experiment before assembly. The inner and outer surfaces on the impeller should be smooth to reduce the friction loss of the water flow.
The pump body is also called the pump shell, which is the main body of the pump. It plays the role of supporting and fixing, and is connected with the bracket for mounting bearings.
The function of the pump shaft is to connect the coupling and the motor to pass the torque of the motor to the impeller, so it is the main component of transferring mechanical energy.
Plain bearings use transparent oil as lubricant, and oil to the oil level line. Too much oil should seep along the pump shaft, and too little bearing should overheat and burn out causing accidents! During the operation of the pump, the temperature of the bearing is up to 85 degrees, and the general operation is about 60 degrees.
The packing box is mainly composed of packing, water seal ring, packing barrel, packing gland and water seal tube. The function of the stuffing box is mainly to close the gap between the pump shell and the pump shaft, so that the water flow in the pump does not flow outside and the outside air does not enter the pump, and the vacuum in the pump is always maintained. When the pump shaft and the packing friction generate heat, it is necessary to rely on the water seal pipe to inject water into the water seal ring to cool the packing and maintain the normal operation of the pump. Therefore, special attention should be paid to the inspection of the stuffing box during the operation of the pump, and the stuffing should be replaced after 600 hours of operation.
Application range of centrifugal pump
Centrifugal pumps are widely used, usually in urban water supply systems, HVAC systems, petrochemical industry, shipping, agricultural irrigation, sewage treatment, industrial production, aquaculture and other fields are inseparable from the centrifugal pump figure.
Advantages of centrifugal pump
- Simple structure
- Easy to operate
- Stable performance
- Widely used
- Wide flow and head range
- Low cost of equipment installation, maintenance and overhaul
- Uniform flow, smooth operation, low vibration
Common standard for centrifugal pumps
In the field of petroleum and chemical industry, the most used centrifugal pump international standards are API610, ISO5199 and ANSI 73.1m /B73.2M, etc., and the Chinese standard is GB3215 and GB5656/T.
API610
American petroleum institute (AmericanPetroleumInstitute) published standard API610 purpose is to provide a purchase specification, so that the centrifugal pump manufacturing and procurement.
ISO5199
The International Organization for Standardization publishes ISO5199 Technical Specification for Centrifugal Pumps, Class II (centrifugal pump technical specification Class II), which is mainly based on the German DIN standard.
ASMEB73.1 M/B73.2 M
ASME is The American Society of Mechanical Engineers (ASME).
