Foundry practice method of heavy-duty car forward shaft

The invention relates to a casting and producing method of a front shaft of a heavy-duty car, which belongs to the enginery. The method adopts copper-nickel alloying isothermal quenching magnesium iron which has higher strength and tenacity compared with the traditional copper-molybdenum alloying isothermal quenching magnesium iron, thereby the service life of the front shaft can be improved; a front shaft blank is cast by adopting a sand-coated iron mould process; the spheroidization of the blank is carried out by adopting a tundish-cover crushing method so that the spheroidization is more stably; a process of mechanical processing firstly and isothermal quenching later ensures that the front shaft does not deform; and the isothermal quenching treatment is performed on a salt bath furnace production line with shielding gas atmosphere to produce an austenite plus acicular ferrite matrix, thereby the tenacity of the front shaft is greatly improved. The method achieves the material revolution that forging is substituted by casting and steel is substituted by iron, saves a heavy forging device or the die investment, shortens the production period, and has obvious economic and social benefits.