Molding sand for automatic production line and preparation method thereof

Abstract

The invention provides molding sand for an automatic production line. The molding sand is prepared from the following raw materials in parts by weight: 60-70 parts of returned sand, 180-190 parts of fresh sand, 40-50 parts of pottery clay, 30-40 parts of pulverized coal, 40-45 parts of sodium bentonite, 20-30 parts of calcium bentonite, 4-6 parts of sodium borate, 2-4 parts of aluminum oxide, 2-4 parts of calcium oxide, 14-18 parts of flour, 20-25 parts of iron ore concentrate powder, 20-40 parts of clay, 5-8 parts of foot oil, 2-3 parts of soybean oil and a proper amount of water. The molding sand prepared by carrying out high-temperature calcination on the sand, the fresh sand, the pottery clay and the like in combination with the dispersion and grinding of the foot oil and the like has excellent air permeability, smoothness, mobility, toughness and plasticity. Meanwhile, by using the pulverized coal, the casting burnt-on sand phenomenon is reduced, and the brightness of castings is greatly improved. Compared with conventional molding sand, the molding sand has the advantages that the using amount of the pulverized coal is reduced; and the collapsibility of the molding sand is improved by using the flour and the iron ore concentrate powder. The molding sand has strong mobility, good air permeability and relatively high viscosity and is suitable for automatic molding line production.

Description

Technical field [0001] The invention relates to the field of casting, in particular to a molding sand used in an automatic production line and a preparation method thereof. Background technique [0002] Molding sand is a material used for molding in casting. Molding sand is generally made by mixing molding materials such as raw sand for foundry, molding sand binder, and auxiliary additives in a certain proportion. Natural clay-containing silica sand can also be used. The usual molding sand formulations for aluminum casting have too large a particle size or Too small, the sand diameter is too large, although the air permeability is good, the surface of the aluminum sand part is relatively rough, the smoothness is not good, and the sand diameter is too small, resulting in poor air permeability of the sand mold and pores in the aluminum casting. The pulverized clay green sand, which is widely used at home and abroad, is generally made by mixing raw sand, binders, pulverized coal ad...

AI Technical Summary

Problems solved by technology

Molding sand is generally made by mixing molding materials such as raw sand for casting, molding sand binder and auxiliary additives in a certain proportion. Natural silica sand containing clay can also be used. In the usual molding sand formula for aluminum casting, the particle size of the molding sand is too large or If it is too small, the diameter of the sand material is too large. Although the air permeability is good, the surface of the aluminum sand parts is rough and the finish is not good. The diameter of the sand material is too small, resulting in poor air permeability of the sand mold and air holes in the aluminum casting

Coal powder clay green sand, which is widely used at home and abroad, is generally made of raw sand, binders, coal powder additives, etc. and water. It has a certain anti-sticking sand effect, low material cost, and high production efficiency. However, its consumption is large, the emission is serious, and the coal powder is burned and decomposed in the casting process to produce toxic gas pollution.