Sometimes the technical indicators were normal when the rotation performance was tested in the factory, but the newly installed slewing bearing and slewing ring showed inflexible rotation. In addition, why the slewing bearing is not installed smoothly or even cannot rotate?
Reasons for the unsmooth installation of the slewing bearing
1, mounting hole. The threaded hole of the mounting hole is not standardized, the thread is not completely, and the thread is defective, which causes the bolt to be unable to be screwed in.
2. The center diameter and chord length of the mounting hole are out of tolerance too much, such as 3-5mm, causing the bolt to fail to perforate.
3, the positioning hole and the step size are out of tolerance and cannot be matched.
4. The bearing after heavy load has a dead center or ellipse in rotation, causing it to fail to operate normally.
5. The bearing is not in the installation direction of the installation design drawing, resulting in the opposite direction of the taper pin, which has potential safety hazards.
6. Interference of installation parts, such as tooth tip interference, there will be teeth gnawing phenomenon, and individual parts conflict with each other.
7. The negative clearance design is unreasonable, resulting in oblique force, unbalanced load and clearance after installation.
8. The equipment structure design is unreasonable, causing the debugging to not be carried out normally.
The slewing bearing may be difficult to rotate or unable to rotate
1. Idling of newly purchased products is not flexible
Please check the production date of the slewing bearing. If it takes a long time (such as more than half a year) and the climate is cold, it is possible that the salt mist and other temperament in the raceway will double the rotation resistance, which will make the slewing ring not work properly (cold areas, more prominent in winter) ) Elimination method: If it can run without other abnormalities, it can be used normally.
2, the operation after installation is not flexible
It may be that the surface of the main machine device and the surface of the slewing ring are not properly matched, resulting in that the axial clearance of the slewing ring behind the device cannot compensate for the deformation of the slewing ring. The slewing ring is in a state of negative clearance, and the rolling elements are difficult to run in the raceway (sometimes with abnormalities). Noise) or poor meshing of the large and small gears; or foreign matter stuck in the large and small gears. Elimination method: re-process the plane of the main machine device to make the device plane meet the requirements; re-adjust the gear meshing backlash according to the requirements, especially pay attention to the gear jump position; check to ensure that there is no foreign matter in the meshing position of the large and small gears; exchange a slewing bearing with a larger gap .
3, the operation is not flexible during use
The sealing strip is damaged, causing foreign matter to enter the raceway (such as poor working conditions, dust immersed in the raceway, etc.), and the isolation block is deformed and difficult to operate; there are hard objects or other conditions at the meshing of the large and small gears, such as broken teeth.
The above is an analysis of the annoying reasons why the slewing bearing is not installed smoothly or even cannot rotate. I hope everyone will be helpful after reading it. When testing the rotation performance of the new bearing, it can rotate lightly, but at this time, it does not represent a reasonable index. The contact point, contact angle, and relative position of the connecting point of the channel are in line, and whether the two circles are close to the perfect circle. The two circles are completely or close to positive balance. In layman’s terms, just like the two rails of a train, they should be close to theoretical parallel, high and low parallel, so that the train will be stable, high-speed, orderly and safe. Therefore, to test the rotation performance, the loading experiment is a very important basis and effective means.