Plain bearing failure index

2.0 Wear

Wear Index


2.4 Erosion damage of white metal journal bearing

Click on photograph to enlarge
	Erosion of surface of bearing caused by the presence of large amounts of small size dirt particles in the oil
Main Characteristics	The arrow in the photograph shows the direction of rotation. The erosion damage is clearly caused by dirt particles entering via the oil feed holes in the central circumferential oil groove. Erosive wear is shown by roughening and dulling of the white metal surface.
Cause	Contamination of the lubricant by fine particles. See wear summary for further information on causes and actions.
Note	Contaminant particles smaller in size than the minimum oil film thickness and therefore erosion occurs rather than scoring.
Possible Confusion with Other Types of Damage	Cavitation of the oil film gives similar looking damage (see cavitation erosion), but in the above example the damage develops from the oil supply hole clearly supporting the deduction that particulate erosion is the cause.
Comment	For further verification of the cause, microscopic examination could be undertaken.