In order to judge whether the disassembled bearing can be used, it should be checked after the bearing is cleaned.
Check the state of rolling track surface, rolling surface and mating surface, the wear of cage, the increase of bearing clearance and the damage of irrelevant dimensional accuracy, which are abnormal.
Tapered roller bearings and other separable bearings can inspect the raceway surfaces of rolling elements and outer rings respectively.
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.
The cleaning agent generally uses ordinary gasoline and kerosene.
1. The cleaning of the removed bearing is divided into coarse cleaning and fine cleaning, which are placed in the container respectively, first on the bottom of the metal mesh pad, so that the bearing does not directly contact the stolen goods of the container.
2. During rough cleaning, if the bearing rotates with stolen goods, 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.
3.Fine cleaning is to carefully clean the bearing while rotating in the cleaning oil. In addition, the cleaning oil should always be kept clean. (as shown below)
If the bearing has the following defects, it can no longer be used:
Cracks or notches on any one of the inner ring, outer ring, rolling element and cage;
Any one of the ferrule and rolling element is broken;
The raceway surface, retaining edge and rolling element are significantly jammed;
Significant wear of cage or significant relaxation of willow nail;
There is rust and damage on the raceway surface and rolling element;
The raceway surface and rolling element have serious indentation and scoring;
The inner warp surface of the inner ring and the outer warp surface of the outer ring have obvious creep;
Obvious discoloration caused by heat;
The bearing, sealing ring or dust cover sealed with grease is obviously damaged.
Precautions for bearing use
Rolling bearings are precision components. No matter how high-performance bearings are used, if they are not used properly, they will not get the expected high performance. Precautions for the use of bearings are as follows:
1、 Keep the bearings and their surroundings clean
Even if the small dust invisible to the naked eye enters the bearing, it will increase the wear, vibration and noise of the bearing. The bearing and its surrounding accessories shall be kept clean, especially dust and dirt, tools and environment.
2、 Precautions during use and installation
It is not allowed to punch with force, directly knock the bearing with a hammer, and transfer pressure through the rolling element.
3、 Use appropriate and accurate installation tools
Try to use special tools and try to avoid using things such as cloth and short fiber.
4、 Prevent bearing corrosion
When holding the bearing directly by hand, fully wash the sweat from your hands and apply high-quality mineral oil before operation. Pay special attention to rust prevention in rainy season and summer. However, under some special operating conditions, the bearing can obtain a longer life than the traditional calculation, especially under light load.
These special operating conditions are the surface damage that may be caused when the rolling surface is effectively divided and limited by a lubricating oil film. In fact, under ideal conditions, the so-called permanent bearing life is possible.
Common problems and Countermeasures in bearing use
1. Abnormal load: select appropriate assembly clearance and preload.
2. Poor assembly: improve the machining accuracy of the shaft and improve the installation method.
3. Insufficient lubricant: supplement or use appropriate lubricant.
Large rotary vibration of shaft:
1. Peeling: fatigue peeling, replace the bearing.
2. Poor assembly: improve the machining accuracy of the shaft and improve the installation method.
3. Foreign matter intrusion: clean relevant parts and use clean grease.
Large lubricant leakage and discoloration:
1. Excessive lubricant: reduce lubricant.
2. Foreign matter intrusion: clean relevant parts
Post time: May-10-2022