Remanufacturing and Repairing Technology of Heavy Duty Cardan Shaft Roller End Bushing

Abstract

The invention discloses a remanufacturing repair process of a heave-load universal shaft roller-end shaft sleeve. The remanufacturing repair process comprises the steps of shaft sleeve surface cleaning, component detection, preheating, backing welding, surfacing, stress relief annealing, machining, surface quenching, and inspection and flaw detection, wherein in the step of backing welding, a bottom layer is subjected to surfacing by adopting common solder wires with the good weldability and low hardness; in the step of surfacing, a working layer is subjected to surfacing by adopting flux-cored wires; the chemical components of each flux-cored wire include, by mass, 0.15-0.3% of C, 1.5-2.0% of Mn, 0.3-0.5% of Si, 1.8-2.8% of Cr, 0.5-0.8% of Mo, less than or equal to 0.007% of S, and the balance Fe. According to the remanufacturing repair process, through combination of backing welding, surfacing and the surface quenching process, the requirements for the size of the repaired roller-endshaft sleeve can be ensured well; moreover, the repaired roller-end shaft sleeve has high wear resistance and high strength; and accordingly, the requirements for a production field are met.

Description

technical field [0001] The invention belongs to the field of mechanical manufacturing, and in particular relates to a remanufacturing and repairing process of a roller end sleeve of a heavy-duty cardan shaft. Background technique [0002] The cardan shaft roll end bushing is an important connecting piece on the steel hot rolling production line. Its main function is to connect the work roll and transmit the motor power to it, so as to realize the rotation of the upper and lower work rolls and realize the continuous rolling of the steel strip. During the steel rolling process, the roll end bushing will be repeatedly squeezed by the impact load. At the same time, there is axial fretting friction between the work roll and the roll end bushing, so the roll end bushing wears quickly and the service life is short. At present, for the failed roller end bushing, the traditional repair process is: direct surfacing + machining, but the traditional surfacing has the following problems:...

AI Technical Summary

Problems solved by technology

During the steel rolling process, the roll end sleeve flat will be repeatedly squeezed by the impact load, and at the same time there is axial fretting friction between the work roll and the roll end sleeve, so the roll end sleeve wears quickly and the service life is short

At present, for the failed roller end bushing, the traditional repair process is: direct surfacing + machining, but the traditional surfacing has the following problems: (1) The surfacing is easy to cut with low hardness welding wire, but The hardness is low and the wear resistance is poor, and the surfacing layer cannot be quenched to increase the hardness, so it is difficult to meet the use requirements of the roller end bushing; (2) The surfacing layer is made of high hardness welding wire, the hardness of the surfacing layer is high, and the wear resistance is good , but it is difficult to cut the surfacing layer, and the hardness distribution of the surfacing layer is uneven. At the same time, the high-hardness welding wire has a high carbon equivalent, which is prone to welding cracks, and it is difficult to control the welding process.

In addition, this kind of welding wire generally contains strong carbide-forming elements such as V and Ti, which often lead to uneven hardness of the surfacing layer due to the uneven distribution of these hard phases, thereby affecting the wear resistance of the repaired parts and reducing the service life.