The construction machinery back to the support due to the material pores or interlayers, the hardness of the hardened layer of the raceway, uneven thickness and other manufacturing quality problems or some external causes, causing the hardened layer of the raceway to peel off or the ring gear to break the teeth, the equipment will not be normal. jobs.
For the raceway stripping, we must first make a correct judgment. Peeling occurs, which is generally not easy to see on the outside. According to our experience, when the following conditions occur, it indicates that the raceway has a peeling layer: when the main engine is loaded with rotation, there is a “snap-squeaky” abnormal sound at the raceway, the speed of rotation is uneven or the speed of a certain azimuth is obviously slowed down and accompanied by Slight vibration; the temperature rise of the slewing motor is too high or the current is too large; the keyway of the slewing motor and the hydraulic coupling or the coupling is crushed.
After peeling, it must be repaired in time. Otherwise the stripping area will expand so that the entire
Slewing Ring is scrapped.
The repair method is as follows: first remove the roller or steel ball in the
Slewing Bearing to separate the inner and outer rings; then clean the raceway with gasoline; then use the polishing machine (grinding wheel) to carefully and carefully remove the needle stripping area of Microsoft Corporation of the United States. The hardened layer of the crack that has been generated is ground away, and the bottom of the peeling layer is ground flat; the welding torch is preheated to the raceway, and the medium carbon steel electrode is used for welding (the electrode must be dried before use, and Bake and use), to make the welding layer slightly higher than the surface of the raceway 1-2mm; if the peeling layer is deeper or larger, it should be layered and welded, not to make the base material temperature too high and cause deformation; Rapid cooling produces weld cracks, and thermal insulation measures should be taken immediately after welding to allow him to gradually cool down. After cooling, use a sander to smooth the repair layer so that it is slightly higher than the surface of the raceway. Gradually repair the repaired weld layer with oilstone or metallographic abrasive cloth to make it conform to the height of the normal surface of the raceway, with the corresponding original curvature. The sample is tested until it is qualified; the grease is cleaned on the raceway and the roller (steel ball), and the assembly can be completed.
According to the above method, after the slewing bearing raceway of the tower crane and the like is facilitated, it works normally after long-term use.
The reason for the broken gear ring may be the quality of the casting section of the tooth parent metal (such as defects such as blisters and interlayers, which significantly reduce the bending resistance of the gear); embedded stones or steel bars at the gear teeth during use. The hard object causes the local bending stress of the gear teeth to increase and break.
The repair method is partial repair welding or insert repair. The local repair welding method is: firstly grind the residual crack base of the damaged part with a portable grinding wheel, clean it with gasoline (oil); preheat the spot with the welding torch. When a certain temperature is reached, the medium carbon steel electrode is used to weld the shape of the tooth in the damaged part of the tooth, so that it is 1-2 mm higher than the tooth surface of the party; the experienced machine repair fitter is selected according to the tooth shape test. Until the tooth shape meets the requirements.
When one of the entire teeth of the rotating ring gear is damaged, it can be cut along the root of the tooth and then the root of the tooth is shaped into a shape. Then, a tooth is registered and cut on the same type of used ring gear, and processed into a shape corresponding to the base material, and then placed in the groove, and the toothed template is used to clamp the positioning. In order to ensure the consistency of the pitch, and use the double wire clamp to increase the value, and then weld around the teeth with low carbon steel. Finally, use a tool such as a file to level the weld to ensure that the gear teeth are stabilized.
