Analysis of the wear of the elements of the slewing support of LIEBHERR self-propelled jib cranes

The failure of the slewing support leads to significant economic damage associated with long downtime of equipment due to the impossibility of replacing it with a new one as a result of the imposition of sanctions by unfriendly countries. If earlier, before the introduction of restrictive sanctions (measures), the failure of the was less painful and took from 15 days to one month maximum, now it stretches to 3… 5 months. One of the reasons for the failure of equipment is the wear of the teeth of the wheel and gear of the rotary bearing, which leads to a change in the stress-strain state of the cassettes with rolling elements. There is uneven wear of the wheel in height, with the upper part of the wheel wearing out to a greater extent than the lower part, which leads to slippage between the gear teeth in the upper part to a greater extent than in the lower part. Wear of the teeth of the gear and the turntable leads to uneven and increased wear of the cassettes and cages of the slewing support and, accordingly, to the loss of rolling elements. The established unevenness of wheel wear in its various segments makes it possible to make proposals for improving the wheel design. The studies of the wear of cassettes and rollers made it possible to establish changes in the stress-strain state in the contact zone of the cassette and the roller, which in the future will improve the method of their calculation and make a proposal to improve the connection between the cassette and the roller.