SLS Blog

What Causes Roller Bearings to Fail and Break?

Written by SLS | May 10, 2021

Roller bearings are small components of a mechanical process calling for the combination of two parts with frictionless resistance. While cheap as a part, their failure can be the root cause of thousands in downtime.

This frictionless resistance (or, more so, friction-reduced resistance) is a critical part to ensuring infrastructure remains consistent with low assessments for damage. This is because, typically, a ball bearing or roller bearing in Singapore will feature an inner ring with spinning parts and an outer ring connected to static features.

Unsurprisingly, these two contrasted components can lead to roller bearings and ball bearings to fail and break. Usually, these faults are down to issues such as corrosion, age, overloading or lubrication. However, it’s important to recognize symptoms for all aspects of a roller bearing’s failure in order to act accordingly and perform vital preventive, predictive and reactive maintenance to reduce costs and downtime.

This article features the eight most common causes of roller bearings failing as well as the reason behind these factors: 



1. Lubrication Contamination

Protecting the bearing from contamination is key to securing persistent and smooth running and integration of lubrication. Without applying the proper lubrication practice, bearing failure can occur.  If foreign bodies are introduced to the roller bearing or the roller bearing’s lubricant, you’ll need to filter the bearing or head to SLS Bearings for a new roller bearing in Singapore.

Within the preventive and predictive maintenance strategies of care, it’s key to inspect for discoloration, incorrect lubricant usage, overheating, lubricant leaks, slowed operation, grooving in the racing and excessive wear in the bearing.

To identify this as an issue, you need to include a maintenance scheme looking for the use of hard-wearing seals, debris build-up around the bearing, the washing of hands and tools when handling the bearings, worn seals, using excessive amounts of grease and cracks or vibrations in the race ways of the bearing.

You can also check out one of the bearing maintenance best practices on how to pack a tapered roller bearing with grease here

 

2. Corrosion

When bought, bearings are packed and sealed with an anti-corrosive material. But this begins to wear away after opening. Only when ready for installation should they be unwrapped, inspected and given a protective coat before being inserted into the mechanism. If they’re not ready for use, they need to be stored somewhere with 22°C and 60% humidity.

If a bearing has been exposed to dirt, dust, sand or other oils, it can corrode and cause rusting to form abrasive areas. This can severely impact output quality and will likely seize, resulting downtime and potential breakages to connecting parts.

To identify corrosion, look for red or brown rusting, vibrating bearings or reduced load capacity. Then, source a roller bearing from a trusted bearing supplier in Singapore before ensuring new bearings have extra protective layers and external seals for hostile factory environments.

 

3. Overloading

Overloading a bearing consists of making the bearing work far past manufacturer’s guidelines for temperature, load weight and speed processing. In these cases, a bearing is likely to see areas of wear and fatigue as well as signs of temperature overheating and wear paths from the rolling elements.

In these cases, the only solution is to source a new bearing as quickly as possible to prevent further damage and/or downtime to the production line. When sourcing a new bearing, it is important to either look for an increased load bearing to compensate or to alter the design of the mechanism. However, when speaking to a bearing supplier in Singapore, they’ll direct you to a high-quality manufacturer while advising on the best bearing for the job.

 

4. False Brinelling

False brinelling (not to be confused with true brinelling) is when the bearing is subject to extreme vibrations or wear even in the case of the inner race remaining static. This can wear away lubrication and cause linear wear marks in the axial direction.

Causes of false brinelling include incorrect or careless transportation of the bearing or the full mechanism.

To combat the effects of false brinelling in both a preventive and predictive care format, use anti-wear lubricants in recommended doses as well as ensuring the entire mechanism will have efficient shock absorbing features to remove the chances of vibrations getting to the roller bearing. Without such due care, you’ll need to source a replacement roller bearing from the SLS Bearing Singapore distributors.

 

5. Shielding

Some bearings can be manufactured or bought with shielding options to match the context of use. However, for those that do not use a shield for the bearing balls or the bearing rollers, it can pave the way for other issues such as contamination.

There are two main types of shielding available for the majority of bearing types in a radial and axial design. The first can be steel which seals the bearing against dust particles and other debris that is rife in the context of use. The second is plastic which forms to the bearing and protects against oil or lubricant contamination. In this respect, having a good plastic shield can also maintain lubrication levels within the bearing. Thus, reducing the need for further maintenance and top-up down-the-line.

 

 

6. Spalling (Fit)

When it comes to spalling due to the mismatched fit of objects and loading, the bearing is likely to show symptoms of fractures, loss of material in the races, increased vibration of the bearing, increased operation noise, noticeable spread of ware, overheating in the inner-axial ring (with a tight fit) and the accumulation of small metal particles (with a loose fit).

This is because a fit too tight within the bearing can exceed the recommended manufacture’s radial clearing of the rolling elements. This causes stress on the bearing and further friction in a component designed to reduce friction. In the case of a fitting being too loose, there are micro-movements within the operation that cause vibrations, noise and body damage to the bearing.

To ensure this won’t occur or spread, you need to refer to the manufacturer’s guidelines for proper clearance between bearing components.

 

7. Improper Mounting

If you’re seeing cracking, denting, wear, fractured rings, overheating, failure and incorrect operating speeds, the first thing you should consider is the mounting. Usually, bearings should be mounted with a press fit on the inner ring (or the rotating ring) rather than the outer (static) ring.

Incorrectly mounted bearings can become an issue with a loose housing fitting, a tight fitting and a misaligned fitting.

When righting the fit, handling the bearing needs to be done in a careful and precise manner with all hands and tools being cleaned prior to starting. This will help to prevent the bearing seeing contamination or further damage. If any of the above symptoms in the bearing are heavy, then sourcing a replacement from a bearing supplier in Singapore or elsewhere in the world is an immediate necessity to avoid downtime and costs.

To, then, prevent the issue reoccurring, it’s important to ensure all handlers of the bearing have the correct training and manufacturer’s guidelines.

You can check out our guides here to learn more about the proper way of bearing mounting and dismounting: 

Your Guide to Bearing Mounting- Methods & Tools

Your Guide to Bearing Dismounting- Methods & Tools

 

8. Misalignment

Finally, there’s misalignment. Much like improper mounting, when the bearing has been incorrectly handled, the races and rollers (or balls) can become misaligned.

In some cases, the bearing can handle this. But, in many, there will be signs of wear when the shaft and housing misalign. One such sign is a ball groove or dent that has become apparent when the rollers or balls are not operating in their ideal race or path. Another is the overheating of the bearing itself and separator failure. Therefore, it is really important to understand shaft and housing alignment and fit to prevent early bearing breakdown

The most common causes for misalignment include careless handling, bent shafts, dirt contamination, improper mounting and out-of-square clamping nuts. So, to combat these causes and prevent the need for buying a new roller bearing in Singapore, it’s best to have trained handlers, consistent inspections of the bearing (and adjoining parts) and the use of precision locknuts to ensure they are square. 

We have a collection of case studies with real-world clients that outline a detailed analysis of various bearing failures, check out below and download your free copy:

 Bearings Failure Analysis Case Studies

 

Here For Your Roller Bearing Needs 

If you’re seeing roller bearing failures, it’s important you contact SLS Bearings immediately to reduce downtime and costs. Apart from providing a wide range of bearings and housings products, our team of experienced engineers offers the diagnosis of bearing failure as well as the mounting, dismounting, lubrication, alignment and the best manufacturer options for buying roller bearings.

Please do reach out to us if you would like to find out more information on roller bearing preparation, maintenance, sourcing and repair.