First, conduct a comprehensive inspection of the slewing bearing. After disassembly and disassembly, cleaning, comprehensive inspection and track inspection, it was found that although the track was severely worn, there were no cracks and deep recesses, which belonged to excessive wear caused by normal use. Therefore, the method of repairing the size of such a slewing bearing is adopted, the diameter of the track rollers is increased by 1.0mm, the larger-sized rollers are customized, and all the rollers are replaced with new ones. After assembly, the slewing bearing rotates flexibly, the clearance is normal, and the slewing bearing is repaired.