What are the maintenance works in the use of slewing bearings? How to maintain?

The slewing bearing is an indispensable part of large-scale machinery, and it can be installed in the machine to allow the machine to rotate left and right. At the same time, it can withstand various forces. Because the slewing ring is very important, it needs careful maintenance. More than 96% of the slewing ring failures are caused by lubrication problems, pollution, wear and incorrect operation, which seriously affects its service life and normal performance. Here are some points of maintenance work during use of slewing bearings.

 

1. The slewing bearing is coated with a small amount of grease when it leaves the factory. When the product is used, it should be filled with new grease according to different working conditions.

2. The slewing bearing should be greased regularly. According to different types of slewing bearings, the specific grease filling time is as follows:

A: Ball type: Grease is added every 100 hours of operation.

B; roller type: add grease every 50 hours of operation.

 

If in a special working environment, such as: tropical, high temperature, dusty, high temperature and continuous work, the grease filling cycle should be shortened, and the grease should be filled every 50 hours of work; when the gear is working normally, it should be guaranteed to work every time Apply detergent once every 150 hours. When working vigorously, apply detergent once every 75 hours of work. Note that the teeth must be wiped clean before applying detergent. The machine must be refilled with new grease before and after the long-term stagnation of the machine. Each time the grease is filled, the raceway must be filled until it overflows from the sealing device. When filling the grease, the slewing ring must be slowly turned to make the grease evenly filled in the raceway.

  1. Because there are many comprehensive factors in the use process, the user can choose the grease according to the specific situation. For example, the raceway can use: No. 3, No. 4 graphite grease, industrial grease, No. 203 grease, No. 7002 High and low temperature bearing grease and No. 2 aluminum base grease, etc.

Since the slewing bearing is installed, the pre-tightening force of the bolts should be checked after 100 hours of operation. After that, the pre-tightening force of the bolt should be checked every 500 hours. Sufficient and best efforts must be maintained.

  1. After the equipment has been working for 2000 hours, if a bolt is found to be loose below 80% of the specified torque, the bolt and two adjacent bolts shall be replaced with new ones; if 20% of the bolts are found to be loose to 80% of the specified torque Below, all bolts are replaced with new ones. After the equipment has been working for 14,000 hours, all bolts should be replaced with new ones (Suggestion: after two to four months use, re-firm the solid parts, and then transition to an annual systematic inspection).

5. Pay much attention to the operation of the slewing bearing during use. If you find that the noise, impact, or power suddenly increases, you should stop the machine immediately for inspection until all the faults are eliminated, and disassemble and inspect if necessary.

  1. ​​When the slewing ring is in use, it is forbidden to directly wash the slewing ring with water to avoid water entering the raceway to cause rust; strictly prevent hard foreign objects from approaching or entering the meshing area to avoid tooth injury or unnecessary trouble.
  2. To keep the surface of the slewing bearing clean, choose a suitable solvent for cleaning according to the surface properties of the anti-rust object, so as to avoid serious corrosion. Surface cleaning can use chemical treatment cleaning method and mechanical cleaning method. When the surface is dry, do a good job in controlling the temperature and wait until most of the area is dry before wiping it with gauze. When applying anti-rust oil, different methods should be adopted to apply different methods of bearing surface properties. Miniature bearings can be directly soaked in anti-rust grease. If you encounter a special shape, you can choose the painting method, so that it is not easy to produce accumulation. There are many factors that cause metal corrosion. The chemical composition of the metal itself can also cause corrosion or the temperature and humidity of the environment in which the item exists can also cause corrosion.
  3. The sundries on the surface of the slewing ring should be removed frequently during use, and the sealing strips of the slewing ring should be checked for aging, cracking, damage or detachment. If one of these conditions occurs, the sealing strips should be replaced in time to prevent debris and debris from entering the raceway. If the grease is lost, the corresponding grease should be applied after replacement to avoid jamming or rusting of rolling elements and raceways.

 

The above is a detailed explanation of the maintenance work in the use of the slewing bearing. In short, the slewing bearing will experience noise, impact and other faults after a period of use. The operator should pay attention to observe and check in time to eliminate the fault. Only the correct and reasonable maintenance of the slewing ring can ensure its normal operation, give full play to its performance, and extend its service life.