Slewing bearing is also known as slewing ring bearing. Due to the wide application of slewing bearing and the relatively low cost, proper repair and maintenance are very important to prolong the life of the bearing, and normal maintenance can ensure the normal operation of the bearing. Work, today Hengguan Xiaobian has sorted out the detailed maintenance and daily maintenance methods of slewing ring bearings to share with you, let’s learn together!
1. Maintenance and daily maintenance methods of slewing ring bearings in use
1. Before starting the bearing, refill with new grease according to the working conditions.
2. Grease should be added to the slewing ring bearing regularly. According to the type of bearing and different bearings, the time for adding lubricating oil is as follows:
a: Ball type: add grease every 100 hours of operation;
b: Roller type: add grease every 50 hours of operation;
For example, under high temperature, dusty, high temperature, high temperature and continuous working conditions, the filling time of grease must be shortened and ensured once every 50 hours; in the case of normal operation, it should be applied once every 150 hours , In the case of heavy work, it should be painted every 75 hours. During long periods of downtime, the lubricating oil should be added once, and the raceway should be filled with each refueling until the oil overflows from the seal. When the grease is added, the rotating bearing should be slowly transferred to allow the raceway filled with grease evenly.
3. During the period of use, the dirt on the surface of the slewing bearing should be cleaned regularly, and attention should be paid to whether the bearing sealing ring is aging, cracked, damaged, or falling off. If any of these situations occur, they should be treated immediately to prevent impurities from entering the raceway. And the loss of grease, and apply grease after replacement, so as to avoid the rolling elements and rollers from being stuck or corroded.
4. Due to the influence of various factors in practical application, suitable grease can be selected according to the actual situation, such as graphite grease No. 3, graphite grease No. 4, industrial grease, No. 203 grease, high and low temperature bearing grease 7002 No. 2, aluminum-based grease No. 2, etc. Special attention should be paid to the slewing ring bearing after 100 hours of operation, it should be preloaded, and then every 500 times of operation, it must be fully used.
5. After the accumulative operation of the device for 2000 hours, if one bolt is loose, which is lower than 80% of the specified torque, this bolt should be replaced with two adjacent bolts; if 20% of the bolts are loose and less than 80% of the specified torque, apply New bolt replacement. After 14,000 cumulative operating hours, all bolts are replaced with new ones.
6. During the operation, pay attention to the operating conditions of the slewing bearing. If noise, impact, or sudden increase in power is found, the operation must be stopped immediately until all faults are eliminated. If necessary, it must be disassembled.
7. When using the slewing ring bearing, it is strictly forbidden to use water to directly wash the rotating bearing to prevent the water flow from flowing into the raceway and cause rust; prevent hard objects from approaching or entering the meshing area to avoid damage or cause unnecessary trouble.
8. Customers have a common misunderstanding about the maintenance of slewing bearings. They think that the lubricating oil of the slewing bearing is the same as the lubricating cycle of the big and small arms, and it needs to be pumped every day. But the opposite is true. If the lubrication cycle is too short, it will lead to excessive lubricating oil in the bearing, causing the seal ring to rupture and leak. In the case of leakage, there will also be impurities infiltrated into the bearing, affecting the work of the bearing. Usually the lubrication time of the rotary bearing is 250 hours. In the process of oiling, turn the machine while stirring, and oiling every 15 degrees is enough. According to your work intensity, it can be adjusted appropriately for different usage situations. Lubrication is usually done once a week or so.
9. When lubricating the rotary motor, it is necessary to know that the lubrication cycle of the rotary motor is 1000 hours. In normal work, the amount of rotary oil should be checked from the oil dipstick. Sometimes abnormal wear occurs. We need to open the window of the large gear to see See if the lubricating oil leaks from the seal ring into the large gear cavity. In addition to the above maintenance measures, we should also frequently check whether the screws of the gear and the sealing ring of the rotary bearing are damaged. Some small gaps outside will be covered by mud. If it is not found in time, it is easy to cause the turntable to break or even cause an accident.
10. Maintenance points of large turntable bearings: large turntable bearings are composed of large gears, reducers, center sections, etc. Generally, when we open the cover next to the boom base, we can see the lubrication condition inside the big gear and the wear condition of the gear. In the process of mechanical operation, the dustproof ring at the rotating center joint will be worn out. If it rains, the rainwater will penetrate into the cavity of the large ring gear through the leakage of the rotating center joint, causing the hub to accumulate water. This will greatly affect the service life of the slewing bearing. When the excavator is working, the grease in the cavity is diluted by water, and the lubrication effect is not ideal, which will increase the wear of the ring gear. Long-term soaking will cause the iron filings on the ring gear to fall off, resulting in abnormal rotation.
slewing ring bearing
2. Storage and maintenance method of unused slewing ring bearings
1. When the slewing bearing leaves the factory, grease has been added to the raceway, and the surface of the slewing bearing is coated with anti-rust lubricating oil. The packaging of the slewing bearing can be individually or integrally packaged according to customer requirements.
2. If it is not installed, the outer surface needs to be lubricated once every six months to prevent rusting. In the south, it is once every three months.
3. The raceway of the slewing bearing should be lubricated once a year, and the bearing should be rotated during maintenance to ensure the elasticity of rotation. After the repair, it must be restored to the original state of the slewing bearing and wrapped with film.
4. When placing the bearing, please place it in a non-corrosive medium, dry and flat room, and must not be immersed in water.
5. When placing the bearing, it should be placed smoothly, not vertically or inclined. When laying flat (except for the entire package), arrange at least 3-5 spacers in the circumferential direction, and the peripheral positions of the upper and lower blocks should be the same. Bearings that have not been used for many years, take special care when starting, especially in rainy areas.