SU1297981A1 - Sand for making moulds - Google Patents

Abstract

The invention relates to foundry and can be used for the manufacture of casting molds primarily in the manufacture of castings from high manganese steels. The purpose of the invention is to obtain a clear imprint of the mold, to prevent the mixture from interacting at the metal-mold interface and to eliminate the mixture burn to casting. This is achieved using a mixture of surfactant, chromium iron and flue dust. The mixture includes, in wt%: refractory clay 4.0-6.0, sulphite-yeast mash 1.0-3.0, solution of bottom residues of fatty acids in white-spirits 1.0-2.0, anionic surfactant 0.07-0.15, chromic iron to 15.0-25.0, flue dust 8.0-10.0, quartz sand - the rest. The introduction of a surfactant into the mixture reduces the coefficient of internal friction of the mixture and improves the quality of the print. The use of a chromium iron in combination with the scaffold dust contributes to the fact that there is no chemical interaction of the liquid metal and its oxides with the forging material. As a result, no burnout is formed. 2 tab. (/) WITH

Description

The invention relates to foundry and can be used to make molds predominantly in the manufacture of castings from high-manganese steels.

The purpose of the invention is to obtain a clear imprint of the form, prevent the interaction of the mixture at the metal-form interface and eliminate the mixture burn to casting.

The mixture contains a refractory filler refractory clay, sulphite-yeast mash, a solution of bottom fatty acid residues in white spirit, anion-active surfactant and heat storage additive.

Quartz sand, which forms the basis of the mixture, is used as a refractory filler.

Refractory clay is introduced to impart a mixture of high raw strength.

The sulphite-yeast brew and the addition of a solution of bottom fatty acid residues in white spirit - the KO fortifier are used as a binder. Surfactant use anion-active, class, in particular the wetting agent NB. Surfactant, affecting the drive of the mixture, reduces the coefficient of internal friction between its particles and thereby improves its mobility, plasticity and improves the quality of the print.

The use of a mixture of chromium iron helps to obtain a clean cast surface due to the inertness of the material, i.e. its ability not to react with the elements of the metal being poured. The heat storage capacity of a chromium iron is better than that of caustic magnesite.

The use of the mixture in the top furnace makes it possible to obtain a layer of iron oxides of the required thickness together with other oxides of the mold material, which contributes to obtaining an easily detachable burn. The blast furnace top dust has a heat-accumulating capacity which, in combination with a chromium iron at its optimal ratio, contributes to the timely solidification of the metal in the lower and upper form.

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max, which provides a dense casting without shrink holes with high indicators of physical and mechanical properties.

The top dust is blast furnace production during the production of iron and mainly contains,%: 55-57J FeO 7.5-12.6; Fe (total) 40-48. The fraction of dust particles is 0.01–0.4 mm, the heat storage capacity is 15–20 kcal / M hail, g 1/2.

The order of preparation of the molding mixture is as follows. Mixing runners load dry quartz sand, chromium iron, flue dust, refractory clay and mix for 2.5-3.0 minutes. Then the sulphite-yeast brew, the KO binder and the NB wetting agent are introduced and mixed for 2-2.5 minutes until the mixture is evenly distributed by volume and the desired crude strength and moisture are obtained.

The compositions of the mixtures, their technological and thermal parameters are given in table. 1 and 2.

When the mixture is used in production, the quality of steel casting is improved, and the conditions and productivity are improved by reducing such defects as burns, burns, shrinkage, and gas shells. Invention Formula

Mixture for making foundry 5 forms Essentially in the production of castings from high-manganese steels with a wall thickness of 3-14 mm, including quartz sand, sulphite-yeast mash, a solution of bottom 0 fatty acid residues in white spirit, refractory clay and heat-accumulating additive, which is in order to get even

five

0

The imprint of the mold, preventing the mixture from interacting at the metal-form interface and eliminating the burn of the mixture to the casting, it additionally contains an anionic surfactant, and as a heat-retaining agent it contains chromium iron and a hot melt drink in the following ratio of ingredients .%:

Refractory clay 4.0-6.0 Sulfite yeast mash1.0-3.0

A solution of bottoms of fatty acids in white spirit 1.0-2.0

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Anionic surfactant

0.07-0.15

Order 850/13 Circulation 741

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., d, 4/5

Production and printing company, Uzhgorod, st. Project, 4

12979814

Hrbmisty iron to

Koloshnikov dust

Quartz sand

Table

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Claims (1)

Claim A mixture for the manufacture of foundry molds mainly in the production of castings of high manganese steels with a wall thickness of 3-14 mm, including quartz sand, sulphite-yeast mash, a solution of distillation residues of fatty acids in white spirit, clay refractory and heat-accumulating additive, characterized in that that, in order to obtain a clear imprint of the mold, to prevent the mixture from interacting at the metal-mold interface and to eliminate the stick of the mixture to the casting, it additionally contains an anionic surfactant, and in as a heat storage additive contains chromium iron ore and blast furnace dust in the following ratio of ingredients, wt.%: Refractory clay Sulphite-yeast mash The solution of bottoms of fatty acids in white spirit 4.0-6.0 1.0-3.0 1.0-2.0 Anionic surfactant 0.07-0.15 Hrbmny zheleznyk Koloshnik dust Quartz sand 15.0-25.0 8.0-10.0 Rest Table 1 Ingredients Content, wt.% 3 Refractory clay 4 5 6 Chromium Iron fifteen 20 25 Blast furnace dust 8 9 10 Sulphite-yeast mash 1 2 3 KO fixer 1 1,5 2 Surfactant 0,07 0.11 0.15 Quartz sand . 70.93 62.39 53.85 table 2 Properties The proposed mixture ___! ________ L * g 3 Heat storage capacity, kcal / m ^2. City 1/2 25 thirty ³⁵ The compressive strength of raw, kgf / cm ² 0.45 0.50 0.55 Humidity,% 4.0 4,5 5,0 Gas permeability 160 150 140 Cast surface quality Satisfactory Satisfactory Satisfactory ritelnoe ritelnoe ritelnoe