Method for preparing gray cast iron

Abstract

The invention discloses a method for preparing gray cast iron, which comprises the following step: adding ductile cast iron returning iron and scrap steel into a cupola for being melted into gray castiron base iron, wherein the ingredients are in the following proportion: 35-40 percent of scrap steel and 60-65 percent of ductile cast iron returning iron. The mixed raw materials of the ductile cast iron returning iron and the scrap steel are only used for preparing the gray cast iron through the smelting of the cupola without using cast iron, thereby not only saving the production cost relatively to traditional ingredients, but also reducing the labor quantity and simultaneously saving metal resources.

Description

technical field [0001] The invention relates to a method for preparing gray cast iron, in particular to a method for preparing gray cast iron by smelting in a cupola furnace, which belongs to the field of casting. Background technique [0002] At present, most of the enterprises producing gray cast iron in the foundry industry still use the traditional batching method of pig iron+returned iron+scrap, which has high production costs and is greatly restricted by the quality, supply and price of raw materials. Especially the soaring pig iron price this year has made many foundry companies Facing losses, suspension of production, or even bankruptcy. [0003] Chinese invention patent 01140111.7 mentions a process for producing ductile iron castings and gray iron castings by smelting cast iron chips in a cupola furnace. The main content of this process is to stir cast iron chips, coagulant, antioxidant, recarburizer, flux and water together After forming a block and solidifying a...

AI Technical Summary

Problems solved by technology

[0004] Although the above-mentioned methods of smelting and preparing gray cast iron have their own characteristics, they all have some defects, such as relatively high production costs caused by many types of raw materials and complicated process steps.