SU1115836A1 - Cold-hardening sand for making moulds and cores - Google Patents

Abstract

COLD MIXTURE FOR THE MANUFACTURE OF CASTING FORMS AND STEM, including a refractory filler, a dehydrated water-insulated cake or a polymer, a thermolysis of wood shale phenols, a polar solvent in the form of an alcohol, a crayfish, a thermotelem of wood shale phenols, a polar solvent in the form of an alcohol, a crayfish, a thermal residue of wood shale phenols, a polar solvent in the form of an alcohol, a crayfish, a thermal residue of wood shale phenols, a polar solvent in the form of an alcohol, a crayfish, a thermal residue of wood shale phenols, a polar solvent in the form of an alcohol, a crayfish, a thermal residue of wood shale phenols, a polar solvent in the form of an alcohol, a crayfish, a thermal residue of wood shale phenols, a polar solvent in the form of an alcohol, and a crayfish; the fact that, in order to improve the quality of the forms and rods by increasing their strength, the mixture additionally contains a surfactant in the form of oil-soluble or water-oil sulphonic acids or sulfonates in the following ratio of ingredients, May. %: A dehydrated water-insoluble settling resin of wood thermolysis 0.2-1.0 Vat residues of shale phenols 0.4-2.0 Polar solvent in the form of alcohols or ketones, or complex (L esters 0.2-0.8 Hardener on Calcium oxide-based 1-2 Surfactant in the form of oil-soluble or water-soluble materials soluble 00 sulfonic acids or CA9 sulfonates 0.05-0.40 O5 Refractory filler Remaining

Description

11 Invention Suited For Foundry, in particular, for mixtures for the manufacture of foundry molds and cores, containing liquid organic products from wood pyrolysis and phenol-containing compounds as a binder. A known mixture for the manufacture of foundry molds and cores, containing a refractory filler, a binder based on wood thermolysis products and the C13 amino compound. However, the mixture does not provide high strength forms and rods, requires heat-drying for curing and contains toxic and deficient products - amines. A cold-hardening mixture for the manufacture of casting molds and cores is also known, which contains a refractory filler that binds in the form of a phenol-alcohol composition and a sedimentary resin obtained during the thermolysis of wood and the hardener is chromic anhydride. However, this mixture is characterized by a high content of binder (4-6%), which worsens the sanitary conditions of production due to the release of gases during the pouring of the metal, leading to a significant release of harmful substances into the atmosphere. In addition, expensive and toxic phenol alcohols are used as modifying additives, and toxic deficient and expensive chromic anhydride is also used as a hardener. Closest to the proposed technical essence and the achieved result is a cold-hardening mixture of a sanitary protection zone for the manufacture of casting molds and cores, containing, May. Z: A dehydrated water-insoluble settling resin of wood thermolysis 0.3-3.0 Distillation residues of shale phenols, 2-2.0 Polar solvent in the form of alcohols or ketones or esters 0.2-0.8 115836 5 out of 10 times for 15 tablespoons 20 rasts thin 25 or lots relative 3Q but 55 fields pa 2 Calcium oxide-based hardener 1.3-3.0 Refractory filler Else However, the strength of the forms and rods of this mixture needs to be increased . The chain of the invention is to improve the quality of the forms and cores for increasing their strength. The goal is achieved that a cold-hardening mixture of the manufacture of casting molds and grouting, including a refractory naniteller, a dehydrated water-insoluble sedimentary resin of thermolysis of the spring, vat residues of shale phenols, alcohols or cel or complex shapes, and body patterns for altir- surface-active substances in the form of oil-soluble, water-oil-soluble sulfoxysilysulfonates at the next ingredients mating, May. %: A dehydrated water-insoluble settling resin of wood thermolysis 0.2-1.0. The bottoms of the rectification of shale phenols 0, 4-2,0 Polar solvent in the form of alcohols or ketones, or esters of 0.2-0.8 Calcium oxide-based hardener 1-2 Surfactant substance in the form of oil-soluble or water-soluble sulfonic acids or sulfonates 0, 05-0.40 Refractory filler Else Introduction of a mixture of one surface-active substance (surfactant) permits by increasing the wettable refractory filler and more thoroughly covering its surface to reduce the content of sludge3 Noah water-insoluble cm Ole nes improve the hygienic properties of the mixture, further increasing the strength and rate of hardening. As surfactants, water-soluble and oil-soluble sulfonates are used, for example, NGL emulsol (GOST 12328-66), or sulfonic acids, such as alkylaryl sulfonic acids of technical grade AC-6 (water-soluble), АС-9,5, DS-8, MS-20) soluble oil (with a molecular weight of 280-400), as well as emulsoles of the grades NG-203 and NG 203A. The lower limit on the molecular weight of the surfactant is 280-300. Surfactants widely used in foundries as blowing agents for water-soluble binders, such as DS-PAC, Petrov's contact, KChNR, nekal, etc., having a molecular weight of about 170-280, due to poor solubility in sedimentary resin and incompatibilities cannot be applied to it. The upper limit of the surfactant for molecular weight is 450-480. With a higher molecular weight, the viscosity of the surfactant increases and their solubility in the binder also deteriorates. The surfactant content in the CTS is 0.05-0.4% by mass. The lower limit of the surfactant concentration is due to their statistically insignificant effect on the strength of the mixtures, the upper one is due to economic considerations and the fact that its further increase does not lead to a greater increase in strength. The dehydrated water-insoluble settling resin (temporary specifications of the Ukrainian SSR, 1-19-15-82) is viscous, the fluid is dark brown (black) in color; with the smell of burnt sugar at a viscosity of 60 + 10 centipoise, density 1.15, 10 g / cm 3, pH 2.45, 0. The bottoms of the rectification of low-grade phenols (for example, shale-chemical waste produced by the Shalechim Kohtla-Järve software) is a solid product, thermocat lytic compaction of shale phenols from brown to black color 364, odor is absent, temperature range of 80-135 grating, contains May %: Higher shale phenols55-95 Neutral substances 5-15 The melting point of phenols is above 260 ° C at a residual pressure of 70 mm Hg, the pH of the water-acetone solution is 5-7. Technical conditions for bottoms are being developed. Ethanol, acetone, methyl ethyl ketone, β-acetate, diethylene glycol, dioxane, mixtures of these components, etc. are used as the polar solvent. The lower limit of the solvent content is due to the required viscosity of the binder and the solubility of the bottoms, the upper economic considerations and safety techniques . As a refractory filler used quartz, zircon, olivine and others. Sands. Calcium oxide, ferrochromic slag, nepheline sludge, Portland cement are used as hardeners. The mixture is prepared as follows; The bottoms are dissolved in a polar solvent, surfactant is added, the mixture is stirred, and poured into a water-insoluble, dewatered settling resin. The resulting binder is mixed with a refractory filler, after which a hardener is added. In tab. 1 shows the proposed compositions XTC (1-5) and the well-known prototype (6). Properties of mixtures 1-6 are shown in table. 2. From the data table. 2 it follows that the proposed mixture provides increased strength of the molds and rods at all stages of curing, which contributes to the improvement of their quality and, consequently, the quality of the castings obtained with their use, can be used to manufacture molds and cores of all types of casting (steel , cast iron, colored alloys).

Table 1

Deteriorated water nepheline sludge calcium oxide 95.1 95.7 Quartz sand 95.25 96.8 96.1. 96.5

Compressive strength, kgf / cm, through:

1 h

3 hours

2A h

Sapability: re:

24 h,%

gas permeability, units

table 2

8.8 8.6 4.8 6.2 4.2 29.2 28.4 18.8 20.4 12.5 39.6 34.8 29.6 36.0 23.0

0.1 0, .1

0.1

0.1-0.2

150

150

150

100-150

Claims (1)

COLD CURING MIXTURE FOR THE PRODUCTION OF CASTING FORMS AND RODS, including refractory filler, dehydrated water-insoluble settling resin for wood thermolysis, distillation residues from the distillation of shale phenols, a polar solvent in the form of alcohols or ketones, calcium or acid solids, or that, in order to improve the quality of molds and cores by increasing their strength, the mixture additionally contains a surfactant in the form of oil-soluble 0.2-1.0 0.4-2.0 or water-soluble sulfonic acids or sulfonates in the following ratio of ingredients, May. %: Dehydrated water-insoluble sedimentary resin for wood thermolysis Distillation residues of shale phenols rectification Polar solvent in the form of alcohols or ketones or esters Calcium oxide hardener Surfactant in the form of oil-soluble or water-insoluble sulfonic acids or sulfonates Refractory 1-2 0.05-0.40 Rest 1 1115836 2