Forming method of straight toothed spur gear compound forge with weight of 1-3 kilos, large diameter and large modulus

Abstract

The invention discloses a forming method of a straight toothed spur gear compound forge, in particular to a forming method of a straight toothed spur gear compound forge with the weight of 1-3 kilos, large diameter and large modulus, which belongs to the technical field of metal plastic processing and comprises the following steps: precisely blanking a round steel bar into billets with a certain length; heating the billets to 720-850DEG C; forging the billets into an intermediate forge piece approximate to the final shape on a mechanical press by using a precision forging die; and after carrying out intermediate annealing treatment, surface spill throwing treatment and phosphating and saponifying lubrication, carrying out cold finishing on the intermediate forge piece into a final forge piece the toothed surface of which is free from being subsequently processed by using a finishing die on a hydropress via utilizing a divided flow precision forging technology. The process method has the advantages of high utilization rate of materials, as well as high precision good performance, good surface quality, stable quality of gear forge pieces and the like.

Description

technical field [0001] The invention relates to a compound precision forging forming method of a spur gear, in particular to a compound precision forging forming method of a spur gear with a weight of 1-3 kg, a large diameter and a large modulus, and belongs to the technical field of metal plastic processing. Background technique [0002] Spur gears are important transmission parts widely used in automobiles, aerospace, machinery and other industries. Their shapes are complex, and their materials, dimensional accuracy, surface quality, and mechanical properties have high requirements. In order to improve the utilization rate of materials and the mechanical properties of gear parts, forging is now used in China to produce gear forgings, which are then machined into gear parts. At present, small-sized spur gears with a weight of less than 1 kg have basically been produced by cold extrusion and precision forging in China, and the tooth profile surface can be realized with littl...

AI Technical Summary

Problems solved by technology

Large-scale spur gears, especially spur gears with a large diameter and a large modulus weighing 1-3 kg, are currently mass-produced in China by cutting the bar into a billet of a certain length and heating it to 1050 -1150℃, use the forging die to forge the blank into a gear blank forging close to the size of the part on the friction press or hot die forging press, and then use the machining method to finish the tooth profile surface, inner hole and end surface to become a finished gear part. The advantage of this method is that the investment in forging equipment is low and the mold is simple. The disadvantage is that the material utilization rate and production efficiency are low. In addition, because the material heating temperature is high during hot forging, the defects such as scale on the surface of the forging are obvious, and the structure of the forging will appear obviously. The austenite grain growth phenomenon, and the surface decarburization layer is deep in the forging production of medium carbon steel gears, which affects the performance of the final parts