Easily-collapsible mud core molding sand and preparation method thereof

Abstract

The invention discloses easily-collapsible mud core molding sand. The easily-collapsible mud core molding sand is prepared from the following raw materials in parts by weight: 200-240 parts of chromite sand, 20-25 parts of sepiolite, 50-56 parts of kaolin powder, 2-5 parts of steel fibers, 20-25 parts of sawdust, 10-15 parts of gypsum powder, 2-3 parts of quick lime, 10-14 parts of corn meal powder, 3-5 parts of furan resin, 1-2 parts of benzenesulfonic acid, 5-7 parts of ethyl acetate and an appropriate amount of water. According to the easily-collapsible mud core molding sand disclosed by the invention, the chromite sand, the sepiolite, the kaolin and the like are roasted and roasted at a high temperature dispersing and grinding of added gypsum powder and the like are combined, so that the molding sand not only has excellent smoothness, gas permeability, cohesiveness, toughness and plasticity, but also has cohesiveness resistance; the steel fibers are used to increase strength of the molding sand; the sawdust is used to increase collapsibility and environment is not polluted. High polymer resin is used as a binding agent, so that the easily-collapsible mud core molding sand is easily collapsible at the high temperature. Besides, the molding sand disclosed by the invention is suitable for facing sand and mud core sand of a large cast steel piece.

Description

technical field [0001] The invention relates to the field of casting, in particular to a collapsible clay core 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 sand, binders,...

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.