Why Is My Split Case Pump Vibrating and Noisy?
Release time:
2025-05-19
Author:
Source:
Why Is My Split Case Pump Vibrating and Noisy?
— Hunan M&W Energy Saving Technology & Science Ltd.
Split case pumps are essential in many industries. But when they start vibrating too much or making loud noises, it can affect both efficiency and safety.
Let’s break down why this happens, how to quickly diagnose it, and what to do about it.
Why It Happens
Cavitation:
– Low inlet pressure causes bubbles → pop → noise & vibration.
Wrong Flow:
– Too much or too little flow causes turbulence inside the pump.
Rotor Issues:
– Impeller imbalance or dirt buildup makes it spin unevenly.
Bearing Problems:
– Worn bearings = more heat and shaking.
Misalignment:
– Shaft or coupling not aligned properly.
Resonance:
– When pump’s vibration matches its natural frequency = big shaking.
How to Check It Quickly
Loud noise? → Check for cavitation.
Hot bearings (>75°C)? → Replace them.
No clear cause? → Do rotor balance check.
Use vibration tool:
1x speed = imbalance
2x speed = misalignment
High pitch = cavitation/bearing issue
How to Fix It
Cavitation:
Close outlet valve a bit, increase inlet pressure
Make suction pipe shorter or wider
Use inducer (for fast pumps)
Mechanical Issues:
Balance the impeller (don't overcorrect)
Use quality bearings (C3 clearance, warm in oil – never hammer!)
System Upgrades:
Heavy base (≥ 3× pump weight)
Rubber joints & proper pipe support
Use VFD (avoid 78–82% speed zone)
Pro Tips for Monitoring
Set vibration alarms (>4.5 mm/s = warning)
Use ultrasound to catch bearing problems early
Use thermal camera to spot motor heat issues
Need help or looking to upgrade your pump?
Click here Contact Customer Service.
Recommended Reading
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2025-12-02
Email: export@mwpump.com
Baoshui Road & Baishi Road, Jiuhua Industrial Zone,
Xiangtan Hunan P.R.C
Tel: +86-731-55599916
WhatsApp: +86 15874130502
Hunan M&W Pump Co., Ltd
