Causes and treatment of noise produced by slewing drive in use

The slewing drive has a wide range of applications and is a product with very high comprehensive load performance, which can withstand large axial and radial loads and tilting moment. The slewing drive will make noise after being used for a period of time. How is the noise generated and how to avoid these problems in the future use?

In fact, the noise of slewing drive is mainly reflected in two aspects, one is the gear meshing part, the other is the slewing bearing part. The design engineers of Unique Transmission summarized the following points for customers’ reference:

1.Due to the noise caused by lubrication, when the slewing drive is delivered from the factory, Unique Transmission will fill Mobil EP2 grease, which can be used at – 10 ℃ – 40 ℃ (normal temperature). High cold and high temperature environment choose Mobil XHP222 long-acting complex lithium grease (resistant to -40℃-150℃ temperature). In case of insufficient lubricant, incorrect lubricant selection or aging hardening, vibration and noise will be generated in the slewing drive, and the noise has no certain regularity. In this case, only select the appropriate lubricant, adjust the lubricant quantity, extend the service life of the lubricant and reasonably determine the replacement period.

2.Noise caused by the entry of foreign matters. When the slewing drive is designed and used, seals will be installed at the slewing bearing groove position and the slewing bearing and housing position to isolate foreign matters (dust, iron filings, water drops, etc.), NBR(nitrile rubber) is generally used for sealing, and different sealing materials should be used for different working conditions. If the seal fails for a long time and is not replaced in time, the gap between the sealing strip and the sealing fitting surface will cause the leakage of lubricating grease and the damage caused by foreign matters entering the inside of the slewing drive.

3.Noise caused by uneven mounting surface and loose bolts. In the process of designing and manufacturing the slewing drive, the Unique Transmission ensured that the unevenness of the mounting surface of the slewing drive was within the standard range. When the mounting surface of the customer’s base and slewing drive are not flat, it will pull the slewing drive out of shape, resulting in eccentric load and negative clearance in the slewing bearing channel in the slewing drive, as well as poor gear meshing, resulting in abnormal noise. When the mounting bolts are loose, the elastic deformation of the slewing bearing in the slewing drive will be caused, and the deformation part will form a negative clearance, which will also cause abnormal noise.

At the beginning of the design scheme and in combination with the various installation ways of slewing drive (vertical, horizontal, etc.), the design engineers of Unique Transmission fully considered the operating conditions and selected the optimal lubrication and sealing form, but it’s still necessary to cooperate with customers to make the product’s service life longer.