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Reasons for high vibration and noise in chemical centrifugal pumps and solutions. Simply put, in a chemical centrifugal pump, when the impeller rotates at high speed, it causes the liquid between the blades to rotate as well; due to the effect of centrifugal force, the liquid is thrown from the center of the impeller toward its outer edge, resulting in an increase in kinetic energy. When the liquid enters the pump casing, as the flow channel in the volute-shaped casing gradually expands, the flow velocity of the liquid decreases, and part of its kinetic energy is converted into static pressure energy; as a result, the liquid exits through the discharge port at a higher pressure. Since chemical centrifugal pumps rely primarily on the effect of centrifugal force to transport liquids, they are called chemical centrifugal pumps. If not handled properly, the centripetal force generated by the impeller can cause the pump to vibrate and produce abnormal noises. If a chemical process centrifugal pump exhibits abnormal vibration and noise, it should be stopped immediately for inspection. 1. Dynamic balance testing After disassembling the chemical centrifugal pump, in order to prevent oscillations when the pump is started, a static balance test of the impeller should also be conducted. The impact of internal prerequisites on the pump. Once all the performance issues that the pump can have on its own are eliminated, and if the problem of vibration still cannot be resolved, then the impact of internal conditions on the pump must also be taken into consideration. For example, resonance that occurs when the natural frequency of the pump’s foundation is similar to its vibration frequency, pump oscillations caused by faults in the drive mechanism, and improper alignment between the pipes and the pump can all lead to abnormal oscillations in the pump. It is usually possible to achieve the desired results by using an appropriate response pace. 2. Shaft bending and rotor inspection If the cause of the vibration cannot be identified internally, the pump has to be replaced. First, measure and adjust the shaft curvature; if no improvement is achieved, install the rotor partially and measure the overall runout and deviation. If these values exceed the specified limits, adjustments must be made. 3. Adjustment of the rotor’s position The pump rotor should be aligned with the stator; otherwise, friction and vibrations will occur during pump operation. 4. Bearing inspection Whether there are any problems with the bearing installation or if it has been damaged. 5. Find the center An incorrect center is also a rare cause of fluctuations; it is necessary to adjust the center strictly in accordance with the standards, keeping it within the specified range. 6. Coupling alignment Many chemical centrifugal pumps are driven through couplings, and there are many different types of couplings available. The advantages and disadvantages of the conventional three-claw coupling alignment directly affect the abnormal operation and service life of the coupling, shafts, bearings, mechanical seals, etc. 7. Can the pump foundation be secure? When vibrations occur, the first thing to check is whether the anchor bolts of the chemical centrifugal pump are tight. If not tightened, it will cause oscillation in the chemical centrifugal pump. It is also necessary to consider whether the strength of the foundation footings is sufficient; sometimes, due to design reasons, soft foundations can also cause vibrations.