The use of hearing to recognize irregular operation is a very common method. For example: With the electronic stethoscope to certain parts perceptible abnormal noise often experienced operatives. Oilless bearing is good even turn state will issue a muffled whining sound. If issued a sharp hissing sound, creak sound and other irregular sounds, often means no oil lubricated bearings even turn in a bad situation. Sharp creak noise may be caused due to improper lubrication. Inappropriate bearing clearance will cause a metallic sound. The concave track dent oilless bearing outer ring track will cause vibration, resulting in a smooth and crisp sound. If the percussion scars caused due to the installation will also generate noise, this noise will vary with the level of oilless bearing speed.
If intermittent noise, rolling elements may be damaged. This sound occurs when the damaged surface is rolling out of date, and the oilless bearing if pollutants often will cause a hissing sound. Serious with the Order of the damage will produce irregular and huge noise.
While oil lubricated bearings damaged by listening to perceptible, but usually to no oil lubricated bearings must be replaced immediately not. So, better methods such as the use of condition monitoring instruments such as electronic. Than the old method of using a stick more accurate estimate of oilless bearing position.


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