| Due to the overall development of modern locomotive manufacturing control technology,and the increase of density of locomotive operation and using frequency,HXD3 type electric locomotive,which is serving as domestic freight electric locomotive in main lines,needs parameters test of main components and minute maintenance at specified interval.in order to guarantee the basic performance of the locomotive and satisfy the safety standards of railway transportation.Axle box body as key components of the locomotive’s bogie subjects to vertical force from the car body and horizontal force from the bogie wheel when providing traction effort.During the inspection,which is requested by railway corporation related documents,of axle box body,many severe flaws are detected,as a result,many axle box bodies are condemned as unfit to use.In order to improve the service life of the components and effectively reduce the cost of maintenance of locomotive,the development of reliable repair technology,which meets the requirements of locomotive operation,to recover the performance of the axle box body is highly expected.This paper is mainly focused on axle box body,and with practical experiences and taking into account of the feature of the structure,operation condition and maintenance requirement,a cold welding repair technology for it is developed and applied to its threaded holes.First,a study on the welding performance of the grade C steel which is the material of the axle box body is carried out.Second,after a detailed study,cold welding repair technology for flawed threaded holes is established.Third,an evaluation of the quality of the component after repair is run including nondestructive test,tensile,properties,hardness,side bend and metallographic test.Last,through the tensile test,evaluate the performance of the threaded hole after repair.With the emergence of this technology,both the cost and rejection rate of the axle box body have seen a significant reduction. |
