Maintenance and repair of bearings

March 4, 2020

1、 Maintenance of bearings:
1. Improve the lubrication quality, control the pressure, temperature and flow of the engine oil, and strengthen the engine oil filtration.
2. Use fuel oil and lubricating oil that meet the requirements.
3. It is not good to control the temperature state of the diesel generator set under the condition of supercooling and overheating. In cold weather, the diesel engine shall be preheated before starting, and the engine oil shall enter the friction surface by turning the crankshaft by hand.
4. The surface quality and geometry of bearing and journal shall be strictly guaranteed.
5. The bearing clearance should be appropriate. If the generator set is too large, there will be impact. If it is too small, the lubrication will be poor, and the bearing may burn.
2、 Maintenance method of bearing:
1. When the bearing is removed for inspection, first make appearance records by photography and other methods. In addition, confirm the amount of residual lubricant and sample the lubricant before cleaning the bearing.
(1) Bearing cleaning is divided into rough cleaning and fine cleaning, and a metal grid can be placed at the bottom of the used container.
(2) During rough cleaning, use a brush in the oil to remove the grease or adhesive. At this time, if the bearing is rotated in the oil, pay attention to damage the rolling surface due to foreign matters.
(3) During fine washing, slowly rotate the bearing in the oil and proceed carefully. Generally, the detergent used is neutral diesel oil or kerosene without water, and warm alkaline solution is sometimes used as required. No matter what kind of cleaning agent is used, always filter and keep clean. After cleaning, apply antirust oil or grease on the bearing immediately.
2. Inspection and judgment: in order to judge whether the removed bearing can be reused, the dimensional accuracy, rotation accuracy, internal clearance and mating surface, raceway surface, cage and sealing ring shall be emphatically checked. Since large bearings cannot be rotated by hand, pay attention to check the appearance of rolling body, raceway surface, cage, flange surface, etc. the higher the importance of bearings, the more careful the inspection is.