Meta Description: Learn why bearing vibration increases and how Malaysian factory teams can investigate bearing wear, imbalance, misalignment, looseness and lubrication problems.

 

A gradual increase in bearing vibration can provide early warning that a motor, pump, fan, compressor or gearbox is developing a problem.

 

However, high vibration near a bearing does not automatically mean the bearing itself is damaged.

 

The vibration may originate from imbalance, misalignment, looseness, resonance, the driven machine or changing operating conditions.

 

Maintenance teams should examine the complete machine before replacing the bearing.

 

Common Causes of Increasing Bearing Vibration

 

Possible causes include:

 

Bearing deterioration

 

Mechanical imbalance

 

Shaft misalignment

 

Loose mounting

 

Poor lubrication

 

Excessive lubrication

 

Incorrect belt tension

 

Coupling wear

 

Bent shaft

 

Damaged fan or impeller

 

Gearbox problems

 

Cavitation

 

Structural resonance

 

Changing machine speed or load

 

1. Bearing Deterioration

 

Bearings may deteriorate because of:

 

Normal wear

 

Contamination

 

Moisture

 

Incorrect installation

 

Excessive load

 

Electrical damage

 

Poor lubrication

 

Misalignment

 

High temperature

 

Possible signs include:

 

Increasing vibration

 

Abnormal noise

 

Higher bearing temperature

 

Lubricant discolouration

 

Excessive movement

 

Repeated bearing problems

 

A basic vibration meter detects changes in overall vibration but may not identify the exact internal bearing defect.

 

2. Mechanical Imbalance

 

Imbalance occurs when mass is distributed unevenly around a rotating component.

 

Possible sources include:

 

Dirty fan blades

 

Damaged impeller

 

Missing material

 

Product buildup

 

Uneven pulley

 

Damaged coupling

 

Incorrect repair work

 

Imbalance-related vibration often changes strongly with rotational speed.

 

Use a tachometer to record RPM together with the vibration reading.

 

3. Shaft Misalignment

 

Misalignment may occur between:

 

Motor and pump

 

Motor and gearbox

 

Gearbox and driven equipment

 

Coupled shafts

 

Possible signs include:

 

High axial vibration

 

Hot bearings

 

Coupling wear

 

Seal leakage

 

Repeated bearing replacement

 

Increased motor current

 

Replacing the bearing without correcting alignment may lead to another failure.

 

4. Mechanical Looseness

 

Loose components can amplify vibration.

 

Inspect:

 

Bearing-housing bolts

 

Motor feet

 

Pump feet

 

Baseplate

 

Anchor bolts

 

Guards

 

Covers

 

Structural supports

 

Coupling fasteners

 

A vibration problem may come from the mounting structure rather than the rotating component.

 

5. Lubrication Problems

 

Both insufficient and excessive lubrication can affect bearing condition.

 

Insufficient Lubrication

 

May increase friction, temperature, noise and wear.

 

Excessive Lubrication

 

Can cause churning, heat and seal damage.

 

Incorrect Lubricant

 

May not provide the required viscosity or protection.

 

Record lubricant type, quantity and application date.

 

6. Incorrect Belt Tension

 

Excessive belt tension increases radial load on motor and fan bearings.

 

Insufficient tension can cause:

 

Slippage

 

Heat

 

Belt dust

 

Speed variation

 

Noise

 

Measure both driving and driven speeds where appropriate.

 

7. Coupling Problems

 

A damaged or incorrectly installed coupling may create:

 

Misalignment

 

Looseness

 

Impact

 

Axial vibration

 

Uneven torque transmission

 

Inspect the coupling only after the machine is correctly isolated.

 

8. Bent Shaft

 

A bent shaft may cause cyclic movement and vibration.

 

Possible indications include:

 

Repeated alignment difficulty

 

Shaft runout

 

Uneven seal wear

 

Axial vibration

 

Repeated bearing problems

 

More detailed mechanical measurement may be required to confirm shaft condition.

 

9. Pump Cavitation

 

A pump experiencing cavitation may produce:

 

Crackling or gravel-like noise

 

Unstable vibration

 

Reduced flow

 

Fluctuating pressure

 

Impeller damage

 

Investigate:

 

Suction restriction

 

Low liquid level

 

High fluid temperature

 

Blocked strainers

 

Air entering the system

 

Incorrect pump operating point

 

Cavitation should not be diagnosed from bearing vibration alone.

 

10. Fan Blade Problems

 

Fan vibration may increase because of:

 

Dust buildup

 

Bent blades

 

Corrosion

 

Cracks

 

Missing material

 

Incorrect blade angle

 

Loose blade attachment

 

Inspect the complete fan assembly after safe isolation.

 

11. Gearbox Problems

 

Gear or gearbox-bearing issues may transmit vibration into nearby bearing housings.

 

Check:

 

Input-side vibration

 

Output-side vibration

 

Gearbox temperature

 

Lubricant condition

 

Noise

 

Motor current

 

Equipment load

 

The highest reading may not always be located at the original vibration source.

 

12. Structural Resonance

 

A machine can vibrate strongly when operating speed excites a natural frequency of the structure.

 

Possible signs include:

 

Vibration changes dramatically with small speed changes

 

One direction has much higher vibration

 

Nearby structural components vibrate

 

The machine becomes smoother outside a specific speed range

 

A simple vibration meter can identify the change, but more advanced analysis may be required to confirm resonance.

 

Check Measurement Conditions First

 

Before diagnosing the machine, confirm:

 

Same measurement point

 

Same direction

 

Same sensor mounting

 

Same machine speed

 

Similar load

 

Similar process condition

 

Same instrument setting

 

No nearby equipment change

 

A different measurement position can produce a different reading even when machine condition has not changed.

 

Where Should Vibration Be Measured?

 

Common bearing measurement directions are:

 

Horizontal

 

Vertical

 

Axial

 

Possible locations include:

 

Motor drive-end bearing

 

Motor non-drive-end bearing

 

Pump bearings

 

Fan bearings

 

Gearbox input bearing

 

Gearbox output bearing

 

Mark or photograph each measurement point for future inspections.

 

Useful Supporting Measurements

 

Temperature

 

Use an infrared thermometer or thermal camera to identify abnormal bearing heat.

 

Rotational Speed

 

Use a tachometer to confirm that readings are taken at comparable RPM.

 

Motor Current

 

Use a clamp meter to check whether the machine load has changed.

 

Noise

 

Use a sound level meter to document changes in overall equipment noise.

 

Process Information

 

Record pressure, flow, product load or damper position where relevant.

 

Basic Bearing Vibration Investigation

 

Step 1: Confirm the Reading

 

Repeat the measurement at the same point and direction.

 

Step 2: Check Machine Speed

 

Record RPM using a tachometer.

 

Step 3: Measure All Relevant Bearings

 

Compare the motor, driven equipment and gearbox.

 

Step 4: Measure in Three Directions

 

Record horizontal, vertical and axial vibration.

 

Step 5: Check Temperature

 

Compare bearing temperatures under the same operating condition.

 

Step 6: Inspect Mounting

 

Look for loose bolts, cracked supports and structural movement.

 

Step 7: Check Lubrication

 

Confirm the correct lubricant, quantity and interval.

 

Step 8: Inspect the Driven Equipment

 

Check the pump, fan, gearbox, conveyor or compressor.

 

Step 9: Compare the Trend

 

Review whether vibration increased gradually or suddenly.

 

Sudden vs Gradual Vibration Increase

 

Sudden Increase

 

Possible causes include:

 

Loose component

 

Broken fan blade

 

Product buildup

 

Coupling damage

 

Process change

 

Incorrect maintenance work

 

Mechanical impact

 

Gradual Increase

 

Possible causes include:

 

Bearing deterioration

 

Progressive misalignment

 

Lubrication problem

 

Gear wear

 

Corrosion

 

Increasing looseness

 

The pattern helps determine the direction of investigation.

 

Vibration Meter Options

 

MTM Precision supplies vibration meters including:

 

Landtek VM-6310

 

Landtek VM-6360

 

Smart Sensor AR63B

 

Benetech GM63B

 

Wintact WT63A

 

Wintact WT63B

 

A basic portable vibration meter is suitable for routine checks and trending.

 

More detailed fault diagnosis may require advanced vibration-analysis equipment and specialist interpretation.

 

Common Bearing Vibration Troubleshooting Mistakes

 

Avoid:

 

Replacing the bearing immediately

 

Measuring at different points each time

 

Ignoring machine speed

 

Ignoring process load

 

Measuring only one bearing

 

Ignoring axial vibration

 

Adding excessive lubricant

 

Failing to inspect mounting bolts

 

Assuming all pump vibration is cavitation

 

Ignoring the motor and driven equipment

 

Comparing different machines without context

 

Continuing operation after a severe or sudden change

 

Bearing Vibration Testing Tools Supplier in Malaysia

 

MTM Precision supplies instruments for investigating bearing vibration, motor condition, pump problems, fan imbalance, gearbox wear and rotating machinery faults.

 

Our range includes vibration meters, tachometers, thermal imaging cameras, infrared thermometers, clamp meters and sound level meters.

 

Contact MTM Precision

 

MTM Precision Sdn. Bhd.

 

Showroom & Service Centre

 

No. 29-1 & 29-2, Jalan Bandar 18,

Pusat Bandar Puchong,

47160 Puchong, Selangor, Malaysia

 

🌐 Website: www.mtmpre.com.my

📧 Email: mtmpre@yahoo.com

📱 WhatsApp: +6016-660 7346