Maintenance And Upkeep Of Rotary Bearings For Rotary Drilling Rigs

Rotary bearings are also known as revolving bearings. Some people also call them: slewing bearings, swivel bearings, and swivel wheels. It is a large bearing that can withstand comprehensive loads and can simultaneously withstand large radial loads, axial and overturning moments.

The first and most widely used application of slewing bearings is in construction machinery, such as rotary drilling rigs, excavators, cranes, pile drivers, graders, rollers, power compactors, tunneling machines, rock drills, etc. The use of slewing bearings has gradually expanded. Equipment platforms such as metallurgical equipment, drilling platforms, and port equipment have begun to use slewing bearings to replace a large number of original bearings.

Working mode of slewing bearing:

According to the design structure and actual usage, there are different working methods for rotary drilling machines. The basic working method is as follows:

(1) The outer ring fixes its supporting function, while the inner ring rotates; (2) The inner ring fixes its supporting function, while the outer ring rotates.

The slewing bearing is an important "joint" of the rotary drilling rig, so its maintenance is very important for the rotary drilling rig.

So how to maintain the rotational support of the rotary drilling rig?

1. Installation of rotating support for rotary drilling rig

① When installing the slewing bearing, the supports on the chassis of the rotary drilling rig (the seats on the upper surface of the inner seat ring and the bottom surface of the support gear ring) must be flat and have sufficient space. strength. To prevent deformation of the rotary bearing, stress relief should be applied to the bearing before assembling it. During the installation process, it is necessary to clean the contact surface and support of the slewing bearing.

② Before fully tightening the bolts, the gears should be checked for meshing. The meshing conditions should meet the requirements of gear accuracy: that is, after the gear pair operates under slight braking, the contact points distributed on the tooth surface should not be less than the height of the gear teeth. 25% along the tooth length direction, not less than 30%.

③ The nuts and bolts connecting the slewing bearings are made of high-strength materials; Double nuts are tightened and prevented from loosening using a rotary drilling rig.

2. Lubrication of the rotating bracket of the rotary drilling rig

① Lubricate the tooth surface of the slewing bearing.

The rotating ring gear has been coated with anti rust oil before leaving the factory. The rust prevention period is 2 to 7 months. After the expiration date, rust proof oil should be applied promptly. During use, please prevent the rotary bearing from being directly exposed to sunlight. Do not rinse the rotary bearing directly with water to prevent water from entering the raceway and to prevent hard foreign objects from entering or entering the tooth engagement area.

② Lubricate the raceway of the turntable.

The raceway should be regularly greased according to the working environment. After the first 55 working hours, the raceway should be filled with lubricating grease, and then refilled every 360 working hours thereafter.

The slewing bearing must be filled with grease before and after long-term placement, and must be hung or stored horizontally. It should not be lifted or stored vertically to avoid deformation.

If using a fixed water or steam jet cleaner to clean a rotary drilling rig, it is necessary to ensure that water does not seep into the slewing bearings and then lubricate the slewing bearing connections.

When the slewing bearing rotates slowly, please add lubricating grease to the rotary drilling rig. When the lubricating grease overflows from the seal, the oil injection is completed. The spilled grease will form a thin film, which serves as a sealing function.

If the construction environment is extremely harsh, please shorten the oil injection cycle.

3. Inspection of the rotating bracket of the rotary drilling rig

① Regularly check whether the rotating gear ring is damaged or broken, and whether the meshing tooth surface is bitten, peeled off, bitten, etc;

② Regularly check the rotational elasticity; If shaking, impact or noise is found, please stop the machine for inspection and immediately troubleshoot, and disassemble and inspect if necessary;

③ Regularly check the integrity of the sealing ring. If it is found to be detached, please reset it in a timely manner. If damage is found, replace it.

④ To ensure the reliability of bolt operation and avoid insufficient pre tightening force, the pre tightening torque of the bolt should be checked separately after the first 120 hours and 600 hours of the slewing support. After that, should we work every 1?? Check the pre tightening torque every 200 hours.

When performing maintenance work on the rotating bracket of a rotary drilling rig, we must first be alert to the danger of being pulled into the rotating pinion and the danger of crushing and shearing. When performing the above tasks, please ensure that no maintenance personnel are in the danger zone between the reel and the exit, or between the main boom, upper vehicle, and main boom when starting the drilling rig for necessary amplitude and rotation operations. The reel area, except for the rotary drilling rig operator (in the cab).