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Centrifugal Pump Energy Saving And Reducing Energy Consumption

Published on 2022/12/19

Centrifugal pump is a kind of general fluid machinery widely used in chemical industry system. It has a wide range of functions and adaptability, including flow rate, pressure head and adaptability to the properties of the conveying medium, small size, simple structure, easy operation, and low operating costs. In recent years, the demand for water pumps and centrifugal pumps in my country has developed rapidly. Benefiting from the continuous improvement of centrifugal pump production technology and the continuous expansion of downstream demand markets, the development of centrifugal pumps in the domestic and international markets is very promising. With the advancement of the manufacturing technology of civil centrifugal pumps, the fields of municipal engineering, farmland water conservancy, drinking water safety engineering, water supply and drainage engineering, and commercial facilities have developed rapidly, driving the continuous expansion of the demand for centrifugal pumps.

Centrifugal Pump

centrifugal pump

When the pump is filled with water, start the motor to make the impeller in the pump rotate at high speed. The water in the impeller leaves the impeller at a high speed under the action of centrifugal force and acquires a certain amount of kinetic energy. Since the water at the impeller inlet is taken out by the impeller, a negative pressure is formed at the impeller inlet.

Under the effect of pressure difference, the water in the water tank is replenished to the inlet of the impeller to form a continuous water flow to achieve the purpose of pumping water. The water thrown from the impeller is scattered, and after being collected by the liquid flow collector, the water flows in an orderly manner along the direction and path specified by the designer, achieving the purpose of saving electricity and draining water efficiently.

Centrifugal pump abnormal causes

1. Reduced rotor balance
When the rotor is unbalanced, the deviation between the center of gravity and the center of gyration of the rotor is too large, and an unbalanced force will be generated during rotation, especially when the rotation speed is high, the vibration generated is more obvious. On the one hand, the balance of the rotor may not meet the design requirements during manufacture or assembly; on the other hand, it may be that after the pump has been running for a certain period of time, some reasons, such as shaft force deformation, excessive partial wear of parts, etc., may reduce the balance accuracy of the rotor. In both cases it is necessary to rebalance the rotor.

2. The flow channel of the impeller is blocked
When the impeller channel is blocked by foreign matter, causing the impeller to be heavy and unevenly stressed, it is necessary to remove the impeller for thorough cleaning.

3. The centrifugal pump is in the non-design working area
Centrifugal pumps operate around the design point, and try to avoid running in small flow areas and large flow areas, otherwise the increase in hydraulic impact will cause vibration. When the water flows from the outer end of the impeller blade and passes near the guide vane or the tongue of the volute pump, a hydraulic shock will occur, and the degree of the shock will increase with the increase of the speed and size of the pump. When this hydraulic impulse is transmitted to the piping system and foundation, noise and vibration are generated. If the frequency of this hydraulic pulse is close to the natural frequency of the pump shaft, piping system or foundation, more severe resonance will occur. In practice, the vibration caused by hydraulic impact can be prevented and mitigated by the following methods or measures:

  • Appropriately increase the distance between the outer diameter of the impeller and the tongue of the pump casing, that is, increase the gap between the water outlet of the impeller.
  • Change the shape of the flow channel, try to avoid sudden changes in the area of the flow channel or sharp changes in the flow direction, so as to alleviate the adverse effects of hydraulic shock.
  • When the multi-stage pump is assembled, the outlet edges of the blades of the impellers at all levels should be staggered according to a certain knot distance. At the same time, the assembly position and orientation of the guide vanes should not overlap with each other, but should be arranged in a certain order. These measures will reduce the hydraulic pulse. If changing the resonance frequency of the piping system cannot reduce the hydraulic impact of the pump, only by taking measures to reduce the intensity of the blade pulse in the hydraulic design of the pump can the problem be fundamentally solved.

4. Cavitation occurs
The cavitation process will generate air bubbles and bubble collapse, which will cause vibration and noise. If the vibration is caused by pump cavitation, it is necessary to consider changing the installation height or increasing the system pressure, and may even need to re-select or design the pump.

5. Bearing reasons
If the bearing is damaged, in addition to the increase of its own running noise, the movement of the rotor will lose stability, which will cause the vibration and noise of the pump unit to increase. In addition, excessive radial clearance of the bearing may also cause abnormal noise. At this point the bearing needs to be replaced.


centrifugal pump

6. Reason for installation
For example, if the centrifugal pump and the base, the base and the foundation are loose, or the coaxiality of the coupling between the motor and the pump is too low, etc., vibration and noise may occur, and the connecting bolts need to be re-tightened or re-ali

How to reduce energy consumption

1. According to the situation on site, take corresponding measures in time to deal with it:
①Get in touch with the power supply unit and adjust the power supply voltage to within the specified range;
② Adjust the opening of the outlet valve to make it operate at the normal working point;
③Properly control the pump pressure and displacement, and reduce the operating current of the motor;
④ Adjust the tightness of the packing gland.

2. If the above measures still cannot be eliminated, the pump should be stopped for inspection and treatment:
① Evacuate from the beginning, and drain the air in the pump;
② Check and adjust the lubricating oil circuit pressure, overhaul or replace the bearing bush;
③Replace the damping rubber ring of the coupling;
④ Overhaul or replace the balance disc;
⑤ Carry out three guarantee operations, repair and replace damaged parts;
⑥Cooperate with a professional team to deal with motor failures.

3. Put forward opinions and propositions to improve the mismatch of pump units to the superior production management department and design unit:
①Replace the motor;
② Impeller reduction or cutting impeller.

Due to the strong versatility of centrifugal pump products, the policy standards and support policies of various downstream industries have been improved. Policies such as water environmental protection treatment, water conservancy projects, energy saving and efficiency enhancement will bring greater support to the development of the civil centrifugal pump industry. Centrifugal pumps are the most commonly used water pumps and are used in a wide range of applications. Our Walker pump has a relatively long service life and requires little maintenance, which can effectively save production costs. Contact us get the price!