First open the slew bearing package, check the certificate and label, and confirm that the slew bearing model used is correct.
A. Installation surface
The installation surface should be smooth and clean, and all excess materials such as paint residues, weld beads, burrs, etc. should be removed. When cleaning, be careful not to let solvent penetrate into the turntable bearing, and do not use solvents that damage the sealing material. The mounting surface should be dry and free of lubricants before assembly. Measures should be taken to protect workers and the environment.
The roughness of the mounting surface of the mounting support shall not be greater than Ra=12.5, 6.3μm. The error of the flatness of the mounting surface must be detected for circumferential error and radial error. The circumferential flatness tolerance value has a corresponding standard value range depending on the diameter of the slew bearing raceway.
In order to avoid local overload of the slew plate bearing caused by the unevenness of the installation plane or deformation of the support, the circumferential flatness error can only have one wave in any 180-degree range, and the change is gentle.
B. Stiffness of the support
Standard slew bearings and zero-clearance slew bearings have different requirements for the rigidity of the support.
C. The inner and outer raceways of the positioning slew bearing have a soft belt, which should be placed on both sides of the main load plane. That is, it is staggered 90 degrees from the main load area. There is a blockage or an "S" mark on the soft band.
In addition, check the fit between the slew plate bearing and the mounting surface, usually with a feeler gauge. If the fit is not good, fill it with appropriate material. It is prohibited to perform welding on the support after the slew bearing is installed.
D. Strong bolts
1. Selection of mounting bolts: The specified (size, quantity, strength level, etc.) mounting bolts and washers should be used. Also note:
1) Do not use fully threaded bolts
2) Do not use old bolts and washers
3) Do not use open washers such as elastic ones Washers, etc.
2. Selection of bolt pretightening torque: It is recommended that the pretightening force of ordinary metric bolts be 0.6-0.7 times the bolt yield strength. It is recommended that bolts larger than M27 use hydraulic fastening devices, and the pretightening force should not exceed 85% of the yield strength.
3. Fastening bolts: The slewing bearing should be installed under no load conditions. Note:
Apply a little oil on the threads of the bolt to ensure balanced friction resistance. Do not use glue on the bolt locking parts.
Pre-tightening bolts: Pre-tightening should be staggered in three steps, with the forces in the three steps being 30%, 80% and 100% respectively.
E. Adjusting the gear backlash
When installing a toothed slew bearing, it is important to correctly adjust the gear backlash. You can use a feeler gauge to measure and adjust the highest point of the gear radial runout, or use lead wire or other suitable methods. If the backlash is not within the specified value, the pinion can be moved to change the center distance. After adjustment, turn the slew plate bearing at least one full circle to confirm that there are no other tooth jump points. After the slew plate bearing is finally fixed, check the backlash and false clearance again. The highest point of gear radial runout is marked with green paint in the tooth groove.
F. First time lubrication
1. Raceway lubrication
In order to ensure sufficient lubrication, the drawing or product instruction manual should be refilled before first use. specified grease. Pay special attention to filling all the grease nozzles with grease one by one. It is best to fill the oil while turning the turntable bearing until you see the grease squeezed out.
2. Gear lubrication
During gear lubrication, the tooth surface should be clean. It is recommended to use a clean brush to apply grease to the gears.