In industrial fluid conveying systems,the operating status of motors matched with lobe pumps determines the reliability of the entire production line.Abnormal motor vibration not only causes premature failure of its own bearings and winding insulation breakdown,but also transmits to the pump body through the coupling,resulting in chain failures such as rotor wear and seal leakage,and even unplanned shutdowns in severe cases.

-Bonve Pumps Cam-type Double Lobe Pumps-

I.Core Causes of Vibration in Lobe Pump Motors

1.Electromagnetic System Failures

Power supply side problems are mainly three-phase voltage imbalance and phase loss operation,which have a particularly significant impact on lobe pumps that start and stop frequently.Stator failures include core deformation and loosening,winding disconnection,inter-turn short circuit or wiring errors,which will cause three-phase current imbalance.Rotor failures are manifested as core eccentricity,broken welds of cage bars and end rings,winding errors and poor brush contact,and the vibration will be sharply amplified under high torque conditions.

2.Electromechanical Hybrid Failures

Uneven motor air gap will generate unilateral electromagnetic tension,forming a vicious cycle of"air gap expansion-tension enhancement".Rotor gravity,installation level deviation or incorrect magnetic center alignment will cause axial play,and in severe cases,shaft grinding at the bearing root will occur.

The unique flow pulsation characteristic of lobe pumps exerts periodic impacts on the motor.If the coupling is improperly selected or poorly connected,this impact will be directly converted into motor vibration.In addition,insufficient foundation stiffness,loose anchor bolts,excessive alignment deviation between the pump and the motor,and vibration transmitted by unbalanced pump rotors are all inducing factors.

3.Pure Mechanical System Failures

Mechanical problems of the motor itself include rotor imbalance,bent shaft,abnormal bearing clearance,damaged fan,etc.Coupling fit problems are particularly critical.When lobe pumps convey high-viscosity media,the coupling bears large torque fluctuations,which is prone to tooth surface wear and loose connecting bolts.Some linked shaft systems are well aligned in cold state,but new deviations will occur after operation due to thermal expansion and contraction.

II.Treatment Methods for Vibration of Lobe Pump Motors

1.Electrical Fault Maintenance

First,measure the three-phase DC resistance of the stator.If it is unbalanced,check the welding points of the windings.Use special instruments to detect inter-turn short circuits,and rewind the windings after confirmation.Check the power supply voltage and wiring terminals to ensure stable three-phase power supply.

2.Connection System Fault Handling

When the motor runs normally under no load but the vibration increases after being connected to the pump,focus on checking the alignment accuracy.Recalibrate the coaxiality of the pump and the motor,and check the tooth surface wear and lubrication of the coupling.At the same time,verify the levelness and stiffness of the foundation,and tighten all connecting bolts.

3.Mechanical Fault Maintenance

Measure the air gap between the stator and the rotor,and readjust it if it exceeds the standard.Loose cores are potted with epoxy resin,bent shafts are straightened or replaced.Perform dynamic balance tests on both the motor rotor and the pump rotor simultaneously to eliminate system resonance sources.Check the bearing clearance and journal wear,and replace the bearings if necessary.

Troubleshooting of lobe pump motor vibration should follow the principle of"electrical first,then mechanical;no-load first,then load".Deal with minor faults in time to avoid developing into major equipment accidents and ensure continuous and stable production.

Bonve pump always adheres to the philosophy of "Wholeheartedly Making Good Rotor Pumps," committed to providing global customers with customized conveying and mixing solutions. If you have technical inquiries, selection needs, case references, or other cooperation intentions related to Bonve rotor pumps, please feel free to contact us.  

Service Hotline: 0574-87588986 13586591794  

Official Website: www.bvpumps.com  

Business Email: market@bonvepumps.com  

We look forward to working with you to drive efficiency and innovation in industrial fluid transmission with precision technology.