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Motor gearboxes are used in a variety of applications. Used to transmit mechanical power from an electric motor to a driven component or load. A gearbox is implemented in the motor to determine the required output speed and torque needed for the specific application.

Gearboxes are often a critical part of machinery in the production line, that keep the line moving. Breakdowns of the gearbox can cause catastrophic failures, stopping production and financially impacting businesses. It is important to prevent unexpected failures, a solution is a preventative maintenance system to regularly monitor your asset efficiency.

5 Common Faults in a Motor Gearbox:

A piece of equipment used heavily in manufacturing, motor gearbox failures are common, some failures more common than others:

1. Overheating Motor. Excessive heat within the gearbox can further damage internal components such as bearings and gears. Gearboxes can overheat due to misalignment, operating at too high a speed or insufficient lubrication.
2. Vibration. An imbalance of the gearbox can cause excessive vibration and damage to internal components such as bearings or gears. Noise from the gearbox can be a sign of misalignment, in such case the gearbox should be booked in for repair.
3. Gear Damage. Damage within the gearbox can be caused by overloading, misalignment, or insufficient lubrication. This fault can lead to noise coming from the gearbox or even a breakdown of the machinery.
4. Lubrication Problems. It is important to monitor the lubricant level. If lubricant levels are too low, it can cause overheating and damage to the gearbox.
5. Electrical Failure. Causing damage to the motor gearbox, electrical faults can be caused by a variety of factors such as overloading.

How Bearing Failures Lead to Gearbox Failures

Bearing failures are a primary culprit behind more than half of all gearbox malfunctions. Let’s delve into the reasons and mechanisms behind this significant statistic.

Common Causes of Bearing Failures:

1. Excessive Loads: Bearings frequently fail due to high axial or radial loads. When the forces exerted on the bearings exceed their capacity, it causes deterioration over time.
2. Lubrication Issues: Whether it’s too little or too much lubrication, both scenarios can wreak havoc:
   • Improper Lubrication: Insufficient lubrication leads to increased metal-on-metal friction, which can eventually result in severe mechanical breakdowns.
   • Over-Lubrication: Excess lubricant can elevate internal temperatures and cause friction among fluids, leading to damage.

Secondary Effects of Bearing Failure:

• Mechanical Failures: Sometimes, excessive loading stems from other mechanical failures within the system. For instance, the output shaft might be overloaded, transferring undue stress to the bearings and causing them to degrade.
• Diagnosis Through Wear Patterns: Recognizing bearing wear can help identify issues early. Bearing damage often presents as fatigue or ‘spalling’ on the ball paths, which can be examined to understand the failures.

Understanding these factors is crucial for maintaining gearbox health and preventing further mechanical issues. Regular maintenance focusing on appropriate load management and proper lubrication practices is key to extending both bearing and gearbox life.

How can I Minimise Faults Occurring?

Regular overhauls and maintenance can minimise the risk of unexpected faults. Necessary checks to the machine’s running efficiency helps to prevent damage to internal components.

Lubrication is critical in the operation of a motor gearbox. For the motor gearbox to operate at maximum efficiency, the value should be kept at a suitable level. A sufficient lubricant level prevents gear and bearing failures.

What are 3 indications that my Motor Gearbox is failing?

There are many indications which can present failures occurring within the motor. It is important to manage your assets and when issues are noticed, are investigated for safety reasons. 3 indications of a failing motor Gearbox are:

1. 1. Excessive vibration within the motor is often a sign of misalignment or worn-out bearings. Neutronic have an in-house CEMB ZB2000 balancing machine, to rebalance rotors, pumps, fans, and impellors, this reduces repair turnaround time.
   2. Oil Leaks can indicate a potential seal failure, which can lead to a reduction in lubrication and damage to internal components.
   3. Reduction in power output can impact the overall performance of the motor including reduction in torque, power output, or speed.

These 3 indications are just some which should be monitored. If any of these are identified, they should be looked at by a professional engineer.

How can Preventative Maintenance Reduce Breakdowns?

The main goal is to minimise unplanned downtime when running machinery. Efficient ways to reduce unplanned downtime is by implementing a Condition Monitoring system.

Preventative maintenance and scheduled repairs can reduce unplanned downtime costs. This can be done by identifying faults and acting quickly. Monitoring your assets is crucial to reduce unexpected downtime.

Vibration analysis, Thermal imaging and Laser Shaft Alignment are all ways to gather data on how efficiently your assets are running. Anomalies in the data may point to a potential fault, identifying these faults quickly can help you plan repairs during scheduled downtime.

Establishing a Motor Gearbox Repair Partner?

Neutronic engineers are exceptional at repairing motor gearboxes, SEW-Eurodrive is a popular manufacturing brand which we repair. We have an in-house test rig at our Warrington workshop. This rig is purpose-built to test run all SEW Eurodrive Movimot Inverters after they have been repaired. This provides our customers with a quick repair turnaround.