Method for smelting thin-wall ductile iron gearbox

Abstract

The invention relates to all smelting and casting processes of casting pieces for a ductile iron gearbox of a railway passenger car, in particular to a method for smelting a thin-wall ductile iron gearbox, which is suitable for the smelting and casting process of casting pieces for a bogie gearbox of the railway passenger car. The method for smelting a thin-wall ductile iron gearbox adopts the method of strictly controlling the smelting temperature and casting temperature to guarantee the uniform ingredients of ductile iron and uniform texture, has reasonably-designed alloy ingredients, adopts a three-stage inoculation mode for inoculation treatment, selects accurate spheroidization to guarantee the texture and property of the casting pieces and control the thin-wall ductile iron casting piece to have the spheroidization grade of the fifth grade, the nodularity of more than 90 percent, ferrite content of more than 90 percent, minus 40 DEG C low temperature impact work of more than or equal to 12J, thereby providing a basis for producing the gearbox batch with low temperature strength and good impact toughness. The invention solves the problems of low temperature toughness, poor graphite spheroidization effect and the like of the thin-wall ductile iron casting pieces.

Description

technical field [0001] The invention relates to all smelting and pouring processes of ductile iron gearbox castings for railway passenger cars, in particular to a smelting method for thin-wall ductile iron gearbox castings, which is suitable for the smelting and pouring process of railway passenger car bogie gearbox castings. Background technique [0002] The railway passenger car bogie gearbox is a key component of the passenger car. It has been hung outside the train for a long time, and the working conditions are harsh; , It is necessary to develop anti-fatigue, low-temperature resistant gearbox castings. Most foreign trains operate at a temperature above -20°C, and the low temperature resistance of materials is not high. However, my country has a vast territory, and trains operate in winter, often at temperatures below -20°C or even lower, even reaching -40°C, which must be developed. Key components of passenger cars suitable for the natural conditions of our country. ...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a method for smelting a thin-walled ductile iron gearbox, which solves the problems of low-temperature impact toughness and poor graphite nodularization effect of thin-walled ductile iron castings