Chilled mud-core molding sand manufactured from chromite sand and method for manufacturing chilled mud-core molding sand

Abstract

The invention discloses chilled mud-core molding sand manufactured from chromite sand. The chilled mud-core molding sand is characterized by comprising, by weight, 70-90 parts of recycled sand, 240-260 parts of the chromite sand, 10-15 parts of coal dust, 30-35 parts of sepiolite, 35-40 parts of bentonite, 4-5 parts of rapeseed oil, 35-40 parts of alkali-free glass fibers, 2-3 parts of copper naphthenate, 1-2 parts of boric acid, 5-8 parts of furan resin, 40-45 parts of nanometer-sized kaolin, 2-3 parts of sodium tripolyphosphate, 2-3 parts of benzene sulfonic acid and an appropriate amount of water. A method for manufacturing the chilled mud-core molding sand includes calcining the chromite sand, the sepiolite and the bentonite; then calcining the chromite sand, the sepiolite and the bentonite at a high temperature; dispersing the boric acid, the copper naphthenate and the like into the chromite sand, the sepiolite and the bentonite and grinding raw materials to obtain the molding sand. The chilled mud-core molding sand and the method have the advantages that the chilled mud-core molding sand is excellent in gas permeability, adhesion, toughness, plasticity and collapsibility; the strength of the molding sand is improved owing to the glass fibers and the boric acid; the organic resin and the rapeseed oil are used as adhesion agents, so that the chilled mud-core molding sand is high in plasticity and high-temperature collapsibility; the chilled mud-core molding sand has a chilled characteristic, and the production efficiency is high.

Description

technical field [0001] The invention relates to the field of casting, in particular to chilled core sand made from chromite sand 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 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 molding sand is too large. Although the air permeability is good, the surface of the aluminum sand parts is rough and the finish is not good. If the diameter of the molding sand is too small, the air permeability of the sand mold is not good, and the aluminum castings have pores. Coal powder clay green sand, which is widely used at home and abroad, is generally made of raw s...

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.