Production method of railway wheels

Abstract

The invention discloses a production method of railway wheels. The production method comprises the steps of billet cutting, steel billet heating, shaping, rolling, slow cooling or isothermal treatment, heat treatment and finish machining. According to the production method, rough machining is cancelled, the allowance of the finish machining is appropriately increased, and accordingly the allowance of the tread machining can be increased after the heat treatment, more tread metal close to a surface layer can be removed under the condition that the requirements of the machining accuracy are met, and accordingly the depth of the abnormal structure area under the tread can be reduced or eliminated conveniently. Compared with the conventional process, the depth of the abnormal structure area under the tread is greatly reduced and the consumption of a finish machining tool is reduced under the condition that performance indicators of the produced wheels are basically identical.

Description

technical field [0001] The invention belongs to the field of manufacturing railway steel rolling wheels, and in particular relates to a preparation method of railway wheels with special requirements on the depth of abnormal structures under the tread. Background technique [0002] For a long time, railway steel rolling wheels have basically been produced by the technological process of billet cutting→slab heating→press forming→wheel rolling mill→slow cooling (isothermal) treatment→rough machining→heat treatment→finishing. For the occurrence of rolling defects such as eccentricity, out-of-roundness, and lack of meat, the pass rate of rolling is mainly ensured by increasing the feeding amount. Turning is used for rough machining to ensure the quality of wheel quenching. [0003] The quenching and tempering heat treatment process is widely used in the heat treatment of rolled steel wheels to improve the wear resistance of the wheels, improve the residual stress distribution of...

AI Technical Summary

Problems solved by technology

Under such process conditions, due to the relationship between the cooling rate, the surface layer of the tread and the near-surface layer of the tread are in poor state, which easily leads to the appearance of non-pearlite abnormal structure, which is harder and brittle than the normal ferrite-pearlite structure , under the action of wheel-rail contact stress, it is easy to peel and peel off, destroying the smoothness and integrity of the wheel tread, and it needs to be repaired before it can continue to be used, which directly reduces the service life of the wheel; the existence of abnormal structures makes the surface hardness of the tread obvious As the height increases, it is difficult for the tread of the wheel to deform properly in the initial stage of use to obtain an ideal wheel-rail geometric matching relationship as soon as possible, resulting in excessive contact stress on the rim of the wheel, which is prone to early contact fatigue damage; due to changes in tissue specific volume, it will also Changes the distribution of residual stress in the local area of ​​the wheel tread surface, thereby accelerating the occurrence of "early peeling" and affecting the service life of the wheel; at the same time, due to the existence of high-hardness abnormal tissue areas, it also increases the difficulty of finishing turning and increases the Increased tool consumption and increased production costs

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