CN103567358A - Low gas forming amount molding sand for casting and preparation method thereof - Google Patents

Abstract

The invention discloses low gas forming amount molding sand for casting and a preparation method thereof. The low gas forming amount molding sand comprises the following raw materials in parts by weight: 85-95 parts of quartz sand, 10-15 parts of yellow loam, 5-10 parts of manganese ore slag, 3-6 parts of asbestos powder, 2-3 parts of pine tar, 4-8 parts of volcanic ash, 2-3 parts of soybean protein powder, 1.5-2.5 parts of sodium alginate, 1-2 parts of carboxymethyl cellulose, 0.5-1.5 parts of fatty acid glycerin, 2-4 parts of composite powder and 3-6 parts of water. The low gas forming amount molding sand is low in gas forming amount and relatively good in gas permeability and can be used for preventing detects such as air pores, cold shut, sand inclusion and sand cut from occurring in castings, obviously improving the quality of the castings and reducing the rejection rate of the castings.

Description

Low gas forming amount moulding sand for casting and preparation method thereof

Technical field

the present invention relates to a kind of molding sand and preparation method thereof, be specifically related to a kind of low gas forming amount moulding sand for casting and preparation method thereof.

Background technology

Molding sand is in casting process, to be used for the material of moulding, generally by Modeling Materials such as Foundry sand, moulding sand binder and additional things, is mixed according to a certain percentage.Gas forming amount is one of important performance of molding sand, the too high meeting of gas forming amount cause foundry goods produce pore, cold shut, water less than etc. defect.

Summary of the invention

The object of the present invention is to provide a kind of low gas forming amount moulding sand for casting and preparation method thereof.

For achieving the above object, technical scheme of the present invention is as follows:

A gas forming amount moulding sand for casting, is comprised of the raw material of following weight portion: quartz sand 85-95, yellow soil 10-15, manganese mud 5-10, flake asbestos 3-6, pine tar 2-3, volcanic ash 4-8, soyabean protein powder 2-3, sodium alginate 1.5-2.5, carboxymethyl cellulose 1-2, fatty glyceride 0.5-1.5, composite powder 2-4, water 3-6;

The preparation method of described composite powder is as follows: a, take perlite, fluorite and barite by weight 4-8:3-5:2-3, mix, pulverized 100-150 mesh sieve, then add water making beating and make the slurry that solid content is 50-60%, high speed ball milling 2-3h, spraying is dry; In b, the dried powder of spraying, add the coconut shell flour of 3-5%, the coal dust of the calcirm-fluoride of 2-3%, 1-2% and the yittrium oxide of 0.4-0.8%, 850-880 ℃ of calcining 30-40min, be warming up to again 1200-1250 ℃ of calcining 2-3h, shrend, then be placed in the hydrochloric acid solution that concentration is 15-20%, be heated to boiling speed lapping 20-30min, the sodium hydroxide solution regulator solution PH that is 10-15% by concentration is again to neutral, under 50-70 ℃ of bath temperature, stir 10-15min, filter, with distilled water, clean filter residue, dry; In powder after c, above-mentioned oven dry, add the sodium phosphate trimer of 2-3%, the jade powder of the soybean oil of the calcium stearate of 1-2%, 3-5%, 2-3% and N-(β-aminoethyl of 0.5-1%)-γ-aminopropyltrimethoxysilane, speed lapping 5-10min, dry, cross 200-300 mesh sieve.

The preparation method of low gas forming amount moulding sand for casting, comprises the following steps:

(1), by quartz sand, manganese mud co-grinding, after mistake 200-250 mesh sieve, with yellow soil, flake asbestos, volcanic ash, composite powder, be dry mixed 2-3min;

(2) add again water, soyabean protein powder, sodium alginate, carboxymethyl cellulose, wet mixing 3-4min, then add pine tar and fatty glyceride, and mix 5-8min, shake out.

Beneficial effect of the present invention:

Molding sand of the present invention not only gas forming amount is low, and gas permeability is better, can avoid in foundry goods, producing the defects such as pore, cold shut, burning into sand, sand washing, obviously improves the quality of foundry goods, reduces casting wasted product rate.

The specific embodiment

A gas forming amount moulding sand for casting, is comprised of the raw material of following weight (kg): quartz sand 90, yellow soil 12, manganese mud 7, flake asbestos 4, pine tar 2.5, volcanic ash 6, soyabean protein powder 2, sodium alginate 2, carboxymethyl cellulose 1.5, fatty glyceride 0.8, composite powder 3, water 5;

The preparation method of described composite powder is as follows: a, take perlite, fluorite and barite by weight 4:5:3, mix, pulverized 100 mesh sieves, then adding water making beating, to make solid content be 55% slurry, high speed ball milling 2h, and spraying is dry; In b, the dried powder of spraying, add 4% coconut shell flour, 2% calcirm-fluoride, 1.5% coal dust and 0.5% yittrium oxide, 870 ℃ of calcining 30min, be warming up to 1250 ℃ of calcining 2h, shrend, is then placed in concentration and is 15% hydrochloric acid solution again, be heated to boiling speed lapping 20min, the sodium hydroxide solution regulator solution PH that is 15% by concentration again, to neutral, stirs 10min under 60 ℃ of bath temperatures, filters, with distilled water, clean filter residue, dry; In powder after c, above-mentioned oven dry, add 2% sodium phosphate trimer, 1% calcium stearate, 4% soybean oil, 2% jade powder and N-(β-aminoethyl of 0.5%)-γ-aminopropyltrimethoxysilane, speed lapping 6min, dries, and crosses 200 mesh sieves.

The preparation method of low gas forming amount moulding sand for casting, comprises the following steps:

(1), by quartz sand, manganese mud co-grinding, after mistake 250 mesh sieves, with yellow soil, flake asbestos, volcanic ash, composite powder, be dry mixed 2min;

(2) add again water, soyabean protein powder, sodium alginate, carboxymethyl cellulose, wet mixing 3min, then add pine tar and fatty glyceride, and mix 6min, shake out.

The performance test of the present embodiment molding sand is as follows:

Green compression strength (kPa): 115

Green tensile strength (KPa): 24

Gas permeability: 118

Gas forming amount (cm ³/ g): 10.6

Compact rate of molding (%): 37

Shatter index (%): 81.

Claims (2)

1. one kind low gas forming amount moulding sand for casting, it is characterized in that, by the raw material of following weight portion, formed: quartz sand 85-95, yellow soil 10-15, manganese mud 5-10, flake asbestos 3-6, pine tar 2-3, volcanic ash 4-8, soyabean protein powder 2-3, sodium alginate 1.5-2.5, carboxymethyl cellulose 1-2, fatty glyceride 0.5-1.5, composite powder 2-4, water 3-6;

The preparation method of described composite powder is as follows: a, take perlite, fluorite and barite by weight 4-8:3-5:2-3, mix, pulverized 100-150 mesh sieve, then add water making beating and make the slurry that solid content is 50-60%, high speed ball milling 2-3h, spraying is dry; In b, the dried powder of spraying, add the coconut shell flour of 3-5%, the coal dust of the calcirm-fluoride of 2-3%, 1-2% and the yittrium oxide of 0.4-0.8%, 850-880 ℃ of calcining 30-40min, be warming up to again 1200-1250 ℃ of calcining 2-3h, shrend, then be placed in the hydrochloric acid solution that concentration is 15-20%, be heated to boiling speed lapping 20-30min, the sodium hydroxide solution regulator solution PH that is 10-15% by concentration is again to neutral, under 50-70 ℃ of bath temperature, stir 10-15min, filter, with distilled water, clean filter residue, dry; In powder after c, above-mentioned oven dry, add the sodium phosphate trimer of 2-3%, the jade powder of the soybean oil of the calcium stearate of 1-2%, 3-5%, 2-3% and N-(β-aminoethyl of 0.5-1%)-γ-aminopropyltrimethoxysilane, speed lapping 5-10min, dry, cross 200-300 mesh sieve.

2. the preparation method of low gas forming amount moulding sand for casting as claimed in claim 1, is characterized in that comprising the following steps:

(1), by quartz sand, manganese mud co-grinding, after mistake 200-250 mesh sieve, with yellow soil, flake asbestos, volcanic ash, composite powder, be dry mixed 2-3min;

(2) add again water, soyabean protein powder, sodium alginate, carboxymethyl cellulose, wet mixing 3-4min, then add pine tar and fatty glyceride, and mix 5-8min, shake out.