Maintenance of Using Slewing Bearing on Tower Crane

Maintenance of Using Slewing Bearing on Tower Crane

1. 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.

2. After 10 shifts of tooth surface work, debris should be removed once, and grease should be reapplied.

3.In order to ensure the reliability of bolt work and avoid insufficient bolt pre-tightening force, the pre-tightening torque of bolts should be checked separately for the first 100 hours and 500 hours after the slewing ring is working. After that, the pre-tightening torque should be checked every 1000 hours of work.

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

5. When tightening the nut, lubricate the thread of the bolt and the end face of the nut, and use a torque wrench to tighten it evenly and symmetrically in the circumferential direction. In the final tightening, the pre-tightening torque on each bolt should be roughly uniform.

6. The slewing bearing must be hoisted or stored horizontally. Do not hoist or store vertically to avoid deformation.

7. Before the bolts are completely tightened, the meshing inspection of the gear should be carried out. The meshing condition should meet the requirements of gear accuracy: that is, the contact spots distributed on the tooth surface after the gear pair is operated under slight braking are not in the direction of the gear tooth height Less than 25%, not less than 30% in the length direction of the gear teeth.

8. The bolts and nuts connecting the slewing ring are all high-strength bolts and nuts; double nuts are used for fastening and anti-loosening.

9. Four oil cups are evenly distributed on the upper surface of the gear ring of the slewing ring that is aligned with the raceway, thereby adding grease to the raceway. The relevant technical personnel of Longma Bearing introduced that under normal circumstances, the slewing ring is lubricated once every 50 hours. Each time you add oil, you must add enough oil until the grease leaks from the seal.