Hot forging machining method of positioning hook for train

Abstract

The invention discloses a hot forging machining method of a positioning hook for a train, comprising the following steps of: 1) selecting circular steel with the diameter of 35 mm; utilizing a cutting machine to carry out blanking, wherein the length of a blank piece is 172 mm after cutting; 2) putting the blank piece obtained by the step 1 into an intermediate-frequency heating furnace to be heated, wherein the heating temperature is 1120-1180 DEG C and the heating time is kept for 2-3 min; 3) utilizing an air hammer to stretch two ends of a workpiece obtained by the step 2 and stretching the diameter to 20+ / -2 mm, wherein the hammer is used for stretching for 8-14 times; 4) placing the stretched workpiece into a bending die of a punching machine to carry out bending work; 5) putting the bent workpiece into a molding die in an electric spiral pressing machine; utilizing the molding die to carry out hot forging on the workpiece, wherein the temperature is 900 DEG C and the pressure is 630 T; and 6) putting the workpiece which is subjected to the hot forging into the punching machine to be subjected to edge cutting and punching treatment. According to the hot forging machining method disclosed by the invention, a tempering heat treatment process of the positioning hook of a continuous production line is organically formed by high-temperature normalizing and forging, and the defects of the prior art are overcome; the energy source is saved and the heat treatment quality is improved; the production period is shortened and the production cost is reduced; and the radiation pollution to a workshop environment is reduced.

Description

technical field [0001] The invention relates to the processing field of positioning hooks, in particular to a hot forging processing method of positioning hooks for trains. Background technique [0002] The positioning hook for trains is an important accessory of railway wagons. It is mainly the main part of the upper and lower connection structure between the tank body and the bottom frame. At the same time, it prevents the tank from moving laterally during operation, so the positioning hook itself for railway wagons Has high quality requirements. The manufacturing method of the existing positioning hook for railway freight cars is the method of casting molding, and what the positioning hook casting adopted is sand casting, i.e. water glass sand carbon dioxide hardening process. [0003] It has the following main disadvantages: [0004] The surface is poorly formed, the appearance quality is poor, and there are many defects such as pores, shrinkage cavities, and shrinkage...

AI Technical Summary

Problems solved by technology

[0004] The surface is poorly formed, the appearance quality is poor, and there are many defects such as pores, shrinkage cavities, and shrinkage porosity. The reason for these defects is the structure of the casting itself. Defects such as shrinkage cavity and shrinkage porosity make the internal structure of the molded parts loose, and internal defects are not easy to find, which seriously affects the quality of the molded parts and has potential hazards; in addition, the molding process of the pressing plate requires the core to be formed, the mold or the core Pore ​​defects are prone to occur if it is not completely dry. During the molding process, if the cleaning is not clean, it is easy to produce casting defects such as sand inclusions and sand loss, which will affect the appearance quality of castings.

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