Referring to slewing bearings, positions which are opposite to the roller path on the surface gear ring are set with 4 grease cups, through grease cups to insert lubricating grease. Generally, lubricating once per 50 hours rotation of slewing bearings, and keeping insert enough lubircating grease each time until grease exudating from the sealed part.

Tooth surface should be cleaned for the sundries per every 10 working runs, and be coated with lubricating grease.

In order to assure working reliability of screw bolts, avoid lack of pretightening force, after the first working time of 100 hours and 500 hours, pretightening forces of bolts should be inspected separately, and then pretightening forces should be checked per every 1000hours of working. Screwing bolts and nuts which are used to connecting with screw bearings should be the heavy-duty, and use double-nuts for fastening.

Changes of noise and slewing resisting moment shoud be noticed in use, any abnormal situations, slewing bearings should be overhauled.

When tightening screw nuts, coated with lubricating grease on the thread and head face, using the torque spanner to tighten symmertrically and equally time and time in the periphery direction. At the last time, pretightening forces are generally equal on each screw bolts.

Before each screw bolt is completely tightened, gear meshing should be checked, situation of messhing should be correspond with requirements of accuracy of gear.

lewing bearings must be craned or stored horizontally, vertically should be avoided.

Erection supports of slewing bearings must have enough rigidity, fitting surface needs to be smooth. Before installation, stress relief is necessary, which is used for decreasing deformation rate of erection supports. Contact face between the support and the slewing ring must be cleaned.