The moving and static parts are rubbed against each other.　　 (5) The prime mover itself vibrates, and the coupling can be disconnected for operation inspection.　　 The second reason is the liquid aspect, which may be: 　　 cavitation. The causes of abnormal vibration and noise of the centrifugal pump can be divided into two aspects.　　 The first 5" Submersible Borehole Pumps is mechanical reasons, usually: 　　

(l) Unbalanced rotating parts. This may be caused by the bending of the pump shaft, bearing wear, etc. It can usually be eliminated by reducing the flow rate (such as closing the discharge valve or reducing the speed), lowering the liquid temperature or increasing the injection height. For example, the anchor bolts are loose, the rigidity of the base is insufficient to resonate with the pump, or the base sinks to make the axis misaligned..　

　 (3) The pump base is not good. The vibration and noise caused by this phenomenon are usually generated when the flow rate is large, and the frequency is high (600～25000HZ).

You can check whether the suction vacuum is too large to help judge. In addition to the unqualified rotor dynamic balance after manufacturing or welding repairs, local corrosion, wear or siltation of the impeller may also cause it to lose its balance., or the failure of the axial thrust balance device, which causes the impeller to move axially and touch the pump casing.　　 (4) The pump shaft is misaligned due to poor coupling or improper pipeline installation

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