In order to maintain the original performance of the bearing in good condition for as long as possible, it is necessary to maintain and repair in order to prevent accidents, ensure the reliability of operation and improve productivity and economy. Maintain the operation standard of corresponding mechanical operation conditions and carry out it regularly. The contents include monitoring the operation status, replenishing or changing the lubricant, and regular disassembly inspection. As maintenance items during operation, there are bearing rotation sound, vibration, temperature, lubricant state, etc.

1、 Bearing cleaning.
When disassembling the lower bearing for maintenance, first record the appearance of the bearing, confirm the residual amount of lubricant, and wash the bearing after sampling the lubricant for inspection. As a cleaning agent, gasoline and kerosene are commonly used.

The cleaning of the removed bearing is divided into coarse cleaning and fine cleaning. They are placed in the container respectively. First, put the metal mesh pad on the bottom, so that the bearing does not directly contact the dirt of the container. During rough cleaning, if the bearing rotates with dirt, it will damage the rolling surface of the bearing, which should be paid attention to. In the coarse cleaning oil, use a brush to remove the grease and adhesion. After it is roughly clean, turn to fine cleaning.

Fine cleaning is to carefully clean the bearing while rotating in the cleaning oil. In addition, the cleaning oil should also be kept clean.

Maintenance and judgment of bearing: in order to judge whether the disassembled bearing can be used, it shall be checked after the bearing is cleaned. Check the state of raceway surface, rolling surface and mating surface, wear of cage, increase of bearing clearance and damage irrelevant to the decline of dimensional accuracy. For non separable small ball bearing, support the inner ring horizontally with one hand and rotate the outer ring to confirm whether it is smooth.

Tapered roller bearings and split bearings can inspect the raceway surfaces of rolling elements and outer rings respectively.

Since large bearings cannot be rotated by hand, pay attention to the appearance of rolling elements, raceway surfaces, cages, edge retaining surfaces, etc. the higher the importance of bearings, the more careful the inspection is.

2、 Lubrication of bearings.

Purpose of bearing lubrication:

The lubrication purpose of rolling bearing is to reduce the internal friction and wear of bearing and prevent burning and sticking. Its lubrication effect is as follows.

(1) Reduce friction and wear.

The contact parts of the ring, rolling element and retainer constituting the bearing prevent metal contact and reduce friction and wear.

(2) Extend fatigue life.

The rolling fatigue life of the bearing is prolonged when the rolling contact surface is well lubricated during rotation. On the contrary, if the oil viscosity is low and the lubricating oil film thickness is not good, it will be shortened.

(3) Discharge friction heat and cooling.

The circulating oil supply method can use oil to discharge the heat generated by friction or the heat transmitted from the outside for cooling. Prevent bearing overheating and lubricating oil aging.

(4) Others: it also has the effect of preventing foreign matters from invading the interior of the bearing, or preventing rust and corrosion.

 

Lubrication method:

The lubrication methods of bearings are divided into grease lubrication and oil lubrication. In order to make the bearing function well, first of all, choose the lubrication method suitable for use conditions and purposes. If only lubrication is considered, the lubricity of oil lubrication is dominant. However, grease lubrication has the advantage of simplifying the structure around the bearing. Compare the advantages and disadvantages of grease lubrication and oil lubrication.

3、 Bearing installation:

Whether the bearing is installed correctly affects the accuracy, service life and performance. Therefore, the design and assembly department should fully study the installation of bearings. It is hoped that the installation will be carried out according to the operating standards. Items of operating standards are usually as follows:

(1) Clean bearings and bearing related parts;

(2) Check the size and finish machining of related parts;

(3) Installation;

(4) Inspection after bearing installation;

(5) Supply lubricant.
 

It is hoped that the bearing package will be opened just before installation. General

1 2