NCCER Millwright Practice Exam

What bearing defect is known as false brinelling?

1. Inadequate lubrication

2. Overloading of the bearing

3. Vibration between rollers

4. Contamination of the lubricant

The correct answer is: Vibration between rollers

False brinelling is a bearing defect that occurs due to the relative motion or vibration between stationary rolling elements, like rollers or balls, and the raceways within the bearing. This condition generally arises when a bearing is improperly secured and experiences vibrations while it's not rotating. As a result of these vibrations, the surface of the bearing develops indentations that resemble true brinelling, which is typically caused by excessive loads. In the context of the other choices, inadequate lubrication usually leads to wear and overheating but doesn't specifically cause the characteristic indentations of false brinelling. Overloading can damage bearings, resulting in different wear patterns but not necessarily the specific indentations seen with false brinelling. Contamination of the lubricant can lead to abrasive wear or other issues, but it is not the primary cause of the false brinelling phenomenon. Understanding this defect is crucial for maintaining bearing integrity and ensuring proper equipment operation, emphasizing the importance of secure mounting and minimizing vibrations in machinery.