Abnormal rotation sound detection and analysis is an analysis method that uses auscultation to monitor the working status of bearings. The commonly used tool is a wooden handle long screw screwdriver, or a hard plastic tube with an outer diameter of about 20mm can be used. Relatively speaking, using an electronic stethoscope for monitoring is more conducive to improving the reliability of monitoring. When the bearing is in normal working condition, it runs smoothly, lightly, and without any stagnation. The sound produced is harmonious and without any noise, and a uniform and continuous "clanking" sound or a lower "booming" sound can be heard. The abnormal sound reflects the following bearing faults:
(1) The bearing emits a uniform and continuous "sizzling" sound, which is generated by the rotation of the rolling elements in the inner and outer rings, and includes irregular metal vibration sounds that are independent of the rotational speed. Generally, it is manifested as insufficient grease in the bearing and should be supplemented. If the equipment is shut down for a long time, especially in the low temperature conditions of winter, the bearings may sometimes make a "sizzling rustling" sound during operation, which is related to the decrease in radial clearance of the bearings and the decrease in the working needle penetration of the lubricating grease. The bearing clearance should be adjusted appropriately, and new lubricating grease with a slightly higher needle penetration should be replaced.
(2) The bearing emits a uniform periodic "ho luo" sound in a continuous "whoosh" sound, which is caused by scratches, grooves, and rust spots on the rolling elements and inner and outer raceway. The period of sound is directly proportional to the rotational speed of the bearing. The bearings should be replaced.
(3) The bearing emits irregular and uneven "cracking" sounds, which are caused by impurities such as iron filings and sand particles falling into the bearing. The sound intensity is low and not related to the number of revolutions. The bearings should be cleaned, re greased or replaced with oil.
(4) The bearing emits a continuous and irregular "rustling" sound, which is generally related to the loose fit between the inner ring and the shaft or the loose fit between the outer ring and the bearing hole. When the sound intensity is high, the fit relationship of the bearings should be checked, and any problems should be repaired in a timely manner.
