Machining method of reducing deformation of helical gear after carburizing and quenching

Abstract

The invention provides a machining method of reducing deformation of a helical gear after carburizing and quenching. The machining method comprises the following steps of machining a helix angle variable beta' of reserved reverse deformation on the helical gear before carburizing and quenching of the gear is carried out, and namely before carburizing and quenching process, a machining helix angleof the helical gear is equal to a designed helix angle beta minus a helix angle balance beta' of reverse deformation; and the helix angle variable beta' is set according to the designed helix angle beta of the gear, an axial effective analysis range H of the gear, and axial heat treatment deformation amount M in the processes of gear hobbling or gear shaping. According to the machining method of reducing deformation of the helical gear after carburizing and quenching, on the basis of the law of reverse deformation, the helix angle variable is used for offsetting the distortion amount generatedby heat treatment. The helix angle of the gear after carburizing and quenching meets process requirements, thus ensuring that the deformation of upper and lower sections is not out of tolerance in subsequent axial finish machining after carburizing and quenching of the gear, and therefore the workload of subsequent finish machining as well as the cutting amount of a carburized layer can be reduced.

Description

technical field [0001] The invention relates to a processing method of helical gears, in particular to a processing method for reducing carburizing and quenching deformation of helical gears, and belongs to the technical field of gear processing. Background technique [0002] Helical gears usually use rough machining methods such as hobbing, milling, and shaping. The finishing of the gear teeth adopts fine grinding teeth to ensure the precision requirements of the gears. After carburizing and quenching of the gear, a carburized layer with high hardness and wear resistance is formed on the surface. The overall quenching of the core has high strength and impact toughness. After the overall carburizing and quenching of the gear, it has excellent comprehensive mechanical properties. [0003] The carburizing and quenching process has slow heating, long production cycle and high cost. Since the helical gear is kept at a high temperature of about 900~950°C for a long time, the ri...

AI Technical Summary

Problems solved by technology

Since the helical gear is exposed to high temperatures of around 900~950°C for a long time, the rigidity of the gear is reduced, and the deformation of the gear teeth cannot be controlled during the long-term heat treatment process, resulting in large distortion at high temperatures, resulting in the layer depth of the gear teeth after subsequent processing. Unevenness, large hardness deviation, or even excessive deformation, resulting in black skin that greatly increases the amount of grinding, resulting in higher grinding costs and even scrapping due to excessive deformation of the tooth surface that cannot meet the requirements

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