Print

What is the main cause of bearing failure?

Published:  06 May, 2015

The answer to this month’s trouble shooter is provided by SKF.

Bearings are one of the most important components in machinery. When they fail, costly machine downtime follows. Bearings can fail for a number of major reasons, some of which are more common than others.

The greatest threat to the operating life and performance of a bearing is the ingress of foreign particles. These can include dirt, dust and water, and cause damage in the form of indentations, wear, corrosion and flaking.

The majority of bearing failures are the result of either operational or pre-operational damage. Operational damage occurs during the bearing service period and for two main reasons. The first reason is ineffective lubrication. This causes abrasive and adhesive wear and can be caused by insufficient and excessive lubrication, plus contamination of the lubricant. The second reason is ineffective sealing, which allows foreign particles to cause abrasive wear and moisture corrosion to greatly reduce the efficiency of the bearing.

Pre-operational damage however, occurs prior to or during bearing installation. The main reasons for this include: the use of an incorrectly fitted shaft or housing, causing bearing damage in the form of cracked rings and fretting corrosion; and the use of defective shaft or housing seats, which are deformed under load and cause fretting corrosion.

There are however, a wide range of other reasons why bearing life is reduced, such as static vibration, operational misalignment, overloading and the passage of an excessive electric current through the bearing.

By correctly specifying and installing bearings to meet the demands of an application, the many potential causes of failure can be averted and costly consequences be minimised.

Related Articles

  • Early bearing failure detection reduces machine downtime 

    Condition monitoring is the best way to detect developing bearing problems before they become the cause of costly production machinery failures, says Phil Burge, marketing and communications manager at SKF.

  • Bearing damage: catch it sooner 

    If damage to bearings can be detected early, the potentially extensive downtime and repair costs arising from failure in service can be avoided. Phil Burge, marketing and communications manager at SKF looks at the tell-tale indicators of bearing wear and puts forward the argument for condition monitoring.

  • Five stages of the bearing life cycle  

    Computer modelling programs allow machine designers to determine, with some confidence, how long their bearing is going to last. But not every bearing achieves its calculated life. What other factors, then, are at play in determining the actual life of a bearing? Phil Burge, country communications manager at SKF explains.

  • The state of the art 

    The way bearings are used, designed and manufactured is changing. PWE takes a look at SKF’s have new Generalised Bearing Life Model. The new model uses the same statistical approach as its standard model, and predicts sub-surface fatigue in the same way, but it also includes separate consideration for surface failure modes.

  • Should remanufactured bearings become the norm?  

    It takes approximately 100 process steps to produce a new bearing, compared to roughly ten for a remanufactured bearing, according to SKF. It’s no surprise, therefore, that there has been an increasing demand for remanufactured bearings in heavy duty industrial applications. Chris Johnson* explores this attractive alternative to bearing replacement.

Sign up for the PWE newsletter

Latest issue

To view a digital copy of the latest issue of Plant & Works Engineering, click here.

View the past issue archive here.

To subscribe to the journal please click here.

Poll

"How is your manufacturing business preparing for a net Zero target?"






Twitter