1. Unable to Rotate Normally or Strong Instantaneous Impact

If a rotor pump cannot start after being powered on, common triggers are usually found at the electrical and mechanical levels. On the electrical side, improper inverter parameter matching or motor phase failure can directly lead to power loss; mechanically, foreign objects jamming inside the pump, excessively small rotor installation clearance, or excessive resistance in the discharge pipeline can all hinder rotor operation. If the motor's selected power lacks sufficient margin, it may also be unable to handle the load.

When troubleshooting, first check the electrical circuit, then disassemble and inspect the pump chamber to clear blockages, and measure and adjust the fit clearance between the rotor and the pump cover. For issues like intense vibration at startup, which is often caused by sudden loading, using variable frequency soft start can effectively buffer the mechanical impact.

2. Excessive Vibration and Noise

If abnormal vibration occurs after the equipment runs smoothly, analysis should focus on system matching. If the natural frequency of the pump and pipeline are close, it can easily lead to resonance; an overly long suction pipeline or too many bends can cause cavitation, manifested as pump body shaking accompanied by crackling sounds. Additionally, coupler misalignment and blockage from accumulated debris in the discharge pipeline are also sources of excitation.

Methods to reduce vibration include: adjusting pipeline supports to change the vibration frequency, increasing the diameter of the suction pipeline to reduce friction loss, and re-aligning the concentricity of the pump shaft and motor shaft. If cavitation is caused by excessively high speed, consider operating at a reduced speed.

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3. Pump Body Overheating

Abnormal heating in rotor pumps is often directly related to dry running – when the medium flow is cut off, the rotors rub against each other generating high temperatures, causing rotor expansion or even seizure. If the medium temperature itself is too high, heat will conduct through the pump body; if the lubricating oil ages or deteriorates, reducing its lubricating effect, it can also cause heating in the bearing area.

In daily operation, ensure the suction valve is open and the pipeline is clear to prevent the pump from running dry. Regularly check the oil quality; if emulsification or impurities are found, replace it immediately. For conveying high-temperature media, consider using jacket cooling or upgrading the rotor material.

4. Insufficient Flow and No Discharge

When the discharge flow is significantly lower than the rated value, first suspect wear on the clearance between the rotor and the liner plate – as the gap increases, volumetric efficiency drops, and the medium recirculates from the high-pressure side back to the low-pressure side. If the speed does not reach the design value, the flow will naturally be affected; if the suction pipeline seal is not tight and air is drawn in, the pump operates in a gas-liquid mixed state, also reducing output.

To address such issues, measure the clearance between the rotor's outer diameter and the pump chamber liner; if out of tolerance, replace them as a pair. Also, check suction pipeline flanges and threaded connections for air leaks, and use a tachometer to measure the motor's actual speed. If the flowmeter reading seems inaccurate, perform online calibration.

5. Abnormal Motor Noise

A dull "humming" sound from the motor is usually related to power phase failure or improper setting of the inverter's carrier frequency. When running with a phase failure, motor torque drops significantly and current rises sharply; if the power supply is not cut off promptly, the windings will burn out quickly.

In such a situation, stop the machine immediately and measure the three-phase voltage and current balance. Inverter parameters need to be re-entered according to the motor nameplate to ensure the V/F curve matches the load characteristics.

As a type of high-precision positive displacement equipment, the operating status of a rotor pump directly reflects the system design and maintenance level. By understanding the mechanisms behind fault appearances and standardizing management across installation, operation, and maintenance procedures, you can ensure this equipment operates stably for conveying over the long term.

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.