Method for manufacturing braking products of rail wagons

Abstract

The invention discloses a method for manufacturing braking products of rail wagons. An aluminum alloy liquid forging manufacturing process is applied to manufacturing of the braking products of the rail wagons to effectively solve a plurality of problems of the braking products, manufactured by using the existing gravity casting forming process and die-cast forming process, of the rail wagons. By means of the braking products of the rail wagons manufactured by using the method, the mechanical behavior is that the extension strength delta is larger than 350N / mm<2>, the elongation rate is larger than 4%, and the hardness is larger than 110HB. After the products are formed, the valve body and cover pin hole degree belong to the first level, namely no pin hole exists, the texture density is high, an infiltration process necessary to the existing process after forming is removed, the mechanical behavior of the products is greatly improved, and the products are favorable for whole performance stability of a valve.

Description

technical field [0001] The present invention relates to a method for manufacturing railway wagon brake products. Background technique [0002] Most of the aluminum alloy components used in railway wagon braking products require good air tightness and mechanical properties. The existing aluminum alloy parts for railway wagon braking products adopt gravity casting molding process and die-casting molding process, and the raw materials are all YL112. The mechanical properties of the manufactured aluminum alloy valve body and cover are tensile strength δ b ≥240N / ㎜ 2 , elongation ≥ 1%, hardness ≥ 85HB, the needle hole of the valve body and cover after molding is 2 grades, in order to prevent the valve body and cover from being insufficiently dense, and air passage between the air passages, an impregnation process is required, but After long-term use, the impregnated part still has the above-mentioned defects. [0003] It can be seen that aluminum alloy parts formed by the abov...

AI Technical Summary

Problems solved by technology

The existing aluminum alloy parts for railway wagon braking products adopt gravity casting molding process and die-casting molding process, and the raw materials are all YL112. The mechanical properties of the manufactured aluminum alloy valve body and cover are tensile strength δ b ≥240N / ㎜ 2 , elongation ≥ 1%, hardness ≥ 85HB, the needle hole of the valve body and cover after molding is 2 grades, in order to prevent the valve body and cover from being insufficiently dense, and air passage between the air passages, an impregnation process is required, but After a long time of use, the above-mentioned defects will still exist in the impregnated part

[0003] It can be seen that aluminum alloy parts formed by the above two manufacturing processes are prone to casting defects such as pores, shrinkage cavities, and shrinkage porosity. These casting defects will directly affect the air tightness and mechanical properties of aluminum alloy parts, and then affect Stable performance of the entire railway wagon braking product