Analysis of the causes of water pump vibration There are many reasons for the vibration of the unit and the pump room building. Some factors are both connected and interacting. In summary, there are mainly the following four reasons.
Electrical aspect
The motor is the main equipment of the unit. The internal magnetic imbalance of the motor and the imbalance of other electrical systems often cause vibration and noise. For example, in the operation of an asynchronous motor, the radial alternating magnetic tension between the stator and rotor generated by the interaction of the stator and rotor tooth harmonic magnetic flux, or a large synchronous motor in operation, the stator and rotor magnetic center is inconsistent or the air gap difference in all directions Exceeding the allowable deviation value, etc., may cause the motor to periodically vibrate and make noise.
Mechanical aspect
Motor and water pump rotating parts are unbalanced in quality, shoddy, poor installation quality, asymmetrical axis of the unit, swing exceeding the allowable value, mechanical strength and rigidity of parts are poor, bearing and sealing parts wear and damage, and the critical speed of the water pump appears to be related to the unit The resonance caused by the natural frequency all the time will cause strong vibration and noise.
Hydraulic
Uneven flow rate and pressure distribution at the inlet of the water pump, pressure pulsation of the working fluid at the inlet and outlet of the pump, liquid bypass, drift and de-flow, non-rated working conditions and pump cavitation caused by various reasons are common causes of pump unit vibration s reason. The rapid changes in pressure in the water pipeline and the effect of water hammer caused by dynamic transition processes such as pump startup and shutdown, valve opening and closing, changes in working conditions, and emergency shutdowns often cause vibrations in the pump room and unit.
Hydraulic and other aspects
The unreasonable design of the unit inlet flow passage or the unmatched unit, improper submerged depth of the pump, and unreasonable start and shutdown sequence of the unit will worsen the water inlet conditions, produce vortexes, induce cavitation or aggravate the vibration of the unit and pump room. When the unit that uses the vacuum cut-off to break the siphon is started, if the air entrainment in the hump section is difficult, the siphon time is too long; the design of the shutter door of the shut-off unit is unreasonable, and it keeps hitting the door seat when it is opened and closed at all times; Uneven settlement of the foundation of the pump and motor or poor rigidity of the foundation will also cause the unit to vibrate.
When the user chooses a pump, it is best to go to a sales point approved by the agricultural machinery department, and be sure to recognize the manufacturer. It is recommended to give priority to the purchase of water-filled submersible electric pumps, and to see the brand and product quality certificate. Never buy products with "three noes" (that is, no manufacturer, no production date, no production license), otherwise there will be problems and users will be at a loss.