There are many reasons that lead to the vibration of the unit and pumping station buildings. Some of the factors are related to both the interaction and the interaction. In summary, there are mainly the following four reasons. 1, the electrical motor is the main unit of the unit, the motor internal magnetic imbalance and other electrical system disorders, often caused by vibration and noise. Such as asynchronous motor in operation, due to the stator rotor harmonic magnetic flux interaction between the stator and rotor radial alternating magnetic force, or large synchronous motor in operation, the rotor center of the rotor is inconsistent or in all directions air gap difference Exceeding allowable deviation, etc., may cause the motor to vibrate periodically and make noises. 2, the mechanical aspects of motor and pump rotating parts of the quality imbalance, shoddy, poor quality installation, unit axis asymmetry, the swing exceeds the allowable value, poor mechanical strength and stiffness of parts, bearings and seals wear and tear damage, and the pump critical Speed ​​and the natural frequency of the unit has been caused by the resonance, etc., will have a strong vibration and noise. 3, the hydraulic pump inlet flow velocity and pressure distribution is uneven, the pump import and export of working fluid pressure pulsation, flow around the liquid, partial flow and off flow, non-fixed conditions and various causes of pump cavitation, are common Cause pump unit vibration reasons. The sudden pressure changes in the water pipe and the water hammer effect caused by the dynamic transition process such as start and stop of pumps, valve opening and closing, change of working conditions and emergency stop of accidents also frequently cause vibration of pumping stations and generating units. 4, hydraulic and other aspects of the unit inflow channel design is not unreasonable or not with the unit, the submerged depth of the pump, and the crew to start and stop the order is not reasonable, etc., will deteriorate the water conditions, resulting in vortex, inducing cavitation or aggravating Unit and pump room vibration. If the unit with damaging siphon vacuum cut-off is in operation, if the air in the hump section is entangled with air, it will take too long to form a siphon; Water pump and motor base uneven subsidence or the basis of the poor rigidity and other reasons, will lead to unit vibration.
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