Novel carburizing-constant temperature-quenching process for heavy-duty gears

Abstract

The invention discloses a novel carburizing-constant temperature-quenching process for heavy-duty gears. The process comprises the steps of: (a) after carburizing treatment, cooling down to a temperature range (600-650 DEG C) below Ar1, and carrying out constant temperature for a period of time until the temperature of workpieces is equalized; (b) heating up to quenching temperature, and quenching after carrying out heat insulation for a period of time according to the requirements of the process; and (c) carrying out low-temperature tempering. According to the process, after the carburizing stage for the gears is completed, the gears are cooled down to some temperature below the Ar1 through furnace cooling, and the constant-temperature retention is carried out, so that the first-time phase conversion is realized; the gears are directly heated up to the quenching temperature after the temperature of the gears is equalized at the temperature, so that the second-time phase conversion is realized; and the quenching treatment is carried out, so that the third-time phase conversion is realized. Proved by production practices, the process disclosed by the invention has the advantages that the energy source consumption is remarkably reduced, the oxidation and decarburization of the gears are reduced, the distortion amount is reduced, the heat treatment process flow is shortened, and the efficiency of labor productivity is increased.

Description

technical field [0001] The invention relates to a metal heat treatment process, in particular to a gear heat treatment process. Background technique [0002] Gear is a widely used mechanical transmission part. In mechanical equipment, gear plays an important role in transmitting power, changing speed and direction of rotation. Generally, gears are divided into three categories according to their transmission forms: cylindrical gears are used for transmission between parallel two shafts; bevel gears are used for transmission between intersecting two shafts; worm gears and worms are used for transmission between crossing two shafts. Compared with belt drive, which relies on friction to transmit power, and chain drive, which transmits motion through the meshing of chain and sprocket teeth, gear drive has the advantages of simple structure, relatively fixed transmission ratio, precise transmission ratio, and large transmission load. [0003] Hard tooth surface gears are mainly ...

AI Technical Summary

Problems solved by technology

This process has the disadvantages of long process, high energy consumption, oxidation and decarburization of the gear surface, large distortion, difficult operation of heavy-duty gears in hot state, high labor intensity, and low productivity.

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