1. Pay attention to the change of noise and rotation resistance torque during the use of the tower crane. If there is any abnormal phenomenon, it should be disassembled and inspected.

2. The mounting seat of the slewing ring (the seat supporting the lower bottom surface of the gear ring and the seat placed on the upper surface of the inner seat ring) must have sufficient rigidity, and the mounting surface must be flat. Before assembling the slewing bearing, the bearing should be subjected to stress relief to reduce the deformation of the slewing bearing. The contact surface between the support and the slewing ring must be cleaned up during assembly.

3. When tightening the nut, lubricate the thread of the bolt and the end surface of the nut, and use a torque wrench to tighten it evenly and symmetrically in the circumferential direction. *When tightening the next time, the pre-tightening torque on each bolt should be roughly uniform.

4. After 10 shifts on the tooth surface, the debris should be cleaned up and greased again.