In daily use, the phenomenon of centrifugal pump vibration is not unusual, what is the cause of centrifugal pump vibration? Together to explore the top ten causes of centrifugal pump vibration. First, the cause of centrifugal pump vibration of the top ten reasons - shaft pump is very long, prone to shaft stiffness, deflection is too large, poor shaft straightness, resulting in moving parts (drive shaft) and static parts (plain bearings Or mouth ring) rubbed between the formation of vibration. In addition, the pump shaft is too long, affected by the impact of the flow of water in the pool larger pump to increase the vibration of the underwater part. Shaft end of the balance plate gap is too large, or axial adjustment of the amount of work properly adjusted, will cause the shaft low-frequency movement, resulting in bearing vibration. Eccentricity of the rotary shaft can cause flexural vibration of the shaft. Second, the cause of centrifugal pump vibration of the top ten reasons - the basis and the pump bracket drive device used between the base and the form of contact fixed is not good, the foundation and the motor system absorption, transmission, isolation vibration poor, leading to vibration and motor Exceeded. The pump foundation is loosened or the pump unit forms an elastic foundation during installation or the water pump creates another critical speed difference 1800 from the vibration due to weakening of the foundation stiffness due to the oil blisters which increases the vibration frequency of the pump. Frequency and an external factor frequency close to or equal to, it will increase the pump amplitude. In addition, the foundation anchor bolts loose, resulting in lower restraint stiffness, will make the motor vibration increased. Third, the centrifugal pump causes the top ten causes of vibration - Coupling coupling bolts connecting the poor circumferential spacing, the symmetry is destroyed; Coupling plus eccentric section, will have eccentric force; Coupling cone surface degree Over-poor; static balance of the coupling or dynamic balance is not good; elastic pin and the coupling with the tight, so that elastic loss of elasticity of the pin adjustment function causes the coupling can not be well on the center; With the gap is too large; mechanical wear and tear of the coupling rubber ring caused by coupling rubber ring with a decline in the performance of the coupling bolts used on the quality of each other. These causes vibrations. Fourth, the centrifugal pump causes the top ten causes of vibration - the pump itself when the impeller rotation asymmetric pressure field generated; suction pool and inlet vortex; impeller inside and the vortex, vortex guide vortex occurs and disappears; valve half Open vortex caused by the vibration; due to the limited number of impeller blades caused by the uneven distribution of outlet pressure; impeller off; surge; pulsating pressure within the channel; cavitation; water flow in the pump body, the pump will be There is friction and impact, such as the impact of the water tongue and guide vane leading edge, resulting in vibration; high temperature water boiler feed pump prone to cavitation vibration; pump pressure pulsations, mainly pump impeller seal ring, pump seal ring Of the gap is too large, resulting in pump leakage loss, severe reflux, resulting in rotor axial force imbalance and pressure pulsation, will enhance the vibration. In addition, hot water pump for hot water delivery, if the pump before the start of uneven heating, or pump sliding pin system is not working properly, resulting in thermal expansion of the pump group will trigger the start-up phase of the violent vibration; pump from thermal expansion, etc. In the aspect of internal stress can not be released, it will cause the shaft support system stiffness changes, when the stiffness changes and the system angular frequency multiples integer multiple, the resonance occurs. Five, Centrifugal Pump vibration caused by the top ten reasons - the motor parts loose structure, bearing loose positioning device, the core silicon steel is too loose, the bearing wear due to decreased stiffness caused by the support, will cause vibration. Eccentric mass, rotor bending or mass distribution problems caused by uneven rotor mass distribution, resulting in static and dynamic balance exceeded Sichuan. In addition, squirrel-cage motor rotor cage cages have broken, causing the rotor suffered magnetic field force and rotor inertia imbalance caused by the imbalance caused by vibration, lack of phase motor, the power supply imbalance and other causes can cause vibration. Motor stator windings, due to the quality of the operation of the installation process, resulting in unbalanced resistance between the phase windings, resulting in uneven magnetic field, resulting in an imbalance of electromagnetic force, the electromagnetic force as the excitation force to cause vibration.