Troubleshooting And Bearing Failure Analysis

Do you know what to look for when something’s wrong with your bearings? We’re looking at the VNC process for troubleshooting & bearing failure analysis.

When a roller or ball bearing gets cracked or damaged, it may set your machine to a grinding halt. A bearing failure can be frustrating to say the least. At VNC we know when your vehicle or mechanical application fails due to faulty ball bearings; these setbacks can mean wasted time and money lost. Due to bearing failure, it’s important to know what causes the defect and how you can prevent future issues with your bearings. We’re looking at 4 ways to troubleshoot bearing failures.

Reasons For Bearing Failure – Analysis
When it comes to bearing failure troubleshooting, if you don’t know the problem, you can’t know the solution. Here are some common reasons for ball bearing failure and how to troubleshoot the issues.

1. Not Enough Lubrication
It is said that up to 80% of bearing failure is caused by a lack of lubrication. Improper lubrication can break down the bearing and cause it to function improperly. If your bearing is damaged by improper lubrication it will show discoloration and wear. Always use the correct amount and type of lubricant for your bearing to keep it in good working order.

2. Misalignment
When a roller bearing becomes misaligned, it will put a stop to the fluidity of motion. In most cases, misalignment will eventually lead to improper installation, separating, and overheating. Do a routine check and inspect housings and shafts to ensure they are in working condition.

3. Corrosion
Due to acid, moisture, or broken grease traps, condensation can ruin a ball bearing. You can easily identify ball bearing corrosion spots by doing a visual check of the bearing. If corroded, the bearing will show signs of brown or red staining on the rolling portions. The bearing will also display preload loss and increased vibration when running.

4. Bearing Fatigue
Often called “spalling” in the bearing world, fatigue happens as a result of excessive overloading and misuse of the bearing type. To combat bearing fatigue, check for an increase in noise and vibration when your system is running, and be sure to replace the bearing according to the need of your application.

Since 1993 VNC bearing has been committed to quality customer service. Read our case studies to learn more about our troubleshooting process and services.

Why is proper lubrication important?

After experiencing numerous axle hub failures on new production, a customer called upon VNC to help determine the root cause and solution.

The very next day, VNC traveled to the customer’s site in order to examine the failed axle hubs and review all of the known facts.

While keeping an open mind to all possible root causes, all early indications pointed towards a problem involving inadequate lubrication, however, upon reviewing the site’s assembly and lubrication processes no irregularities were observed.

With inadequate lubrication seemingly ruled out, several failed bearings, as well as the mating components, were disassembled and taken back to VNC’s inspection lab for a more in depth examination.

Forensic Examination:

Although most of the bearings were badly destroyed and difficult to inspect, the forensic examination continued to point towards inadequate lubrication as the root cause of failure.

During the examination the bearing fragments from the raceways and rollers consistently demonstrated severe discoloration and scoring. At such an early stage in their field life, such signs would not occur under proper lubrication conditions.

In addition to the failed bearings, sampling was completed on the current bearing inventories and all bearings were found to meet specifications.

The Hypothesis:

With all components meeting design specifications, no signs of external contamination, and inadequate lubrication seemingly ruled out, the team turned towards the one observation that could not be explained.

Despite the numerous failed axle hubs on new production, every single failure was occurring on the curb side of the axle. If a product defect were causing failures in the field, this affinity to one side of the axle would not occur. Instead the failures should exhibit a random pattern among the assembly locations.

With renewed focus on the curb side of the assembly line, the assembly and lubrication processes at the customer site were reviewed once again in greater detail.

The Solution:

Several days later after an in depth investigation of the lubrication portion of the assembly line, the customer was finally able to identify the root cause for the recent axle hub failures.

With the renewed focus on inadequate lubrication, it was discovered that the lubrication machinery used on the curb side of the assembly line was improperly modified in order to decrease the time for lubrication.

This modification was found to directly cause less lubrication to be applied to the curb side axle hubs. With less lubrication, the bearing components were not receiving ample lubrication in order to protect the bearing components and perform properly.

Once the machinery was returned to normal operating conditions, the curb side axle hubs were once again receiving a proper amount of lubrication during assembly. With the root cause corrected, the axle hub failures were eliminated.

Contact VNC Bearing today to find out how we can help you.