Fault Analysis of Engine roller bearing crankshaft

Once the roller bearing crankshaft of the engine crankshaft fails, it directly affects the technical state of the engine. Therefore, attention should be paid to the failure of the rolling bearing. The common faults of the rolling bearing are analyzed as follows: the rolling bearing cage is worn, deformed or broken, and the lubrication of the crankshaft bearing is splashed. . When the bearing lacks or is not lubricated, especially when the load on the bearing is large, the bearing temperature rises. The inner ring of the bearing is about ten degrees higher than the outer ring. Because the thermal expansion of the inner and outer rings is different, the gap between the balls and the raceways disappears, and the cage is easily crushed during operation. Therefore, when installing the bearing, clean the lubricating oil in the raceway to prevent dry friction when the lubricant is not splashed.

The radial and axial clearance of the roller bearing crankshaft increases, and the radial and axial clearance of the bearing increases, except for dry friction and excessive frictional wear at startup. Mainly because of the metal particles on the surface of the part and the sand, dust and dirt in the lubricating oil, caused by the friction on the rolling elements and the raceway. The bearing has a significant increase in the play between the ferrule and the rolling element due to abrasive wear, a matte surface has formed on the raceway, and uneven scratch marks appear. The method of prevention is to change the lubricating oil on time, and the oiling hole should be sealed to prevent dirt from entering.

When the cooperation between the roller bearing crankshaft and the shaft is loose, some maintenance workers use the embossing of the loose shaft surface or the punching of the shaft to raise the surface of the shaft in an attempt to obtain a tight mating surface. This not only destroys the geometry of the shaft surface, but also causes the bearing to be skewed during the installation without the correct center position, and the raised portion is eventually flattened to become a loose fit.

The correct method of repair is to first grind the journal and then brush or spray the journal. When the inner and outer rings of the rolling bearing are assembled, the bearing balls are caught in the race due to the large amount of interference, and the bearing cage is easily crushed during operation. Therefore, measurements should be made during assembly to ensure standard interference.

Exfoliation due to impact load and alternating stress. The roller bearing crankshaft elements and the inner and outer ring raceways are subjected to periodic pulsating loads, resulting in cyclically varying contact stresses. When the number of stress cycles reaches a certain value, fatigue peeling occurs on the rolling element or the inner and outer ring raceways. If the bearing load is too large, this fatigue will be exacerbated. In order to avoid spalling of the raceway and rolling element surface, additional load and undue vibration should be avoided during use. The throttle and speed should be used reasonably during operation to prevent the tractor from bumping. Always check the fixing body bolt to prevent loosening. 

The damage caused by damage to the raceway during installation. If the pressure is transmitted through the outer ring and the steel ball during installation, it will inevitably cause pits in the part where the ferrule raceway contacts the steel ball. These pits are the source of the damage, and the increase is extremely fierce. The bearing peeling off is scrapped in a short time. Therefore, when using special tools during disassembly, the force parts should be correct and uniform.

If you are finding roller bearing crankshaft or other bearings, please contact me any time!

Contact: Ellen
Email: [email protected]
Skype: +8618668909563
MP/Whatsapp: +8618668909563
Wechat:18668909563