SU1289580A1 - Liquid self-hardening sand for making moulds and cores - Google Patents

Abstract

The invention relates to the field of foundry and can be used to make molds and cores from self-hardening liquid mixtures. The purpose of the invention is to increase the gas permeability of the mixture and improve its knockability. The goal is achieved by introducing the mixture of alkylsulfuric acid and alkylaromatic sulfonic acid in the ratio 1: 3. The mixture according to the invention contains May. %: liquid glass 5.5-6.0, hardener based on dicalcium silicate 2.0-3.0, water 1.6-2.0, mixture of salts of alkyl sulfuric acid and alkylaromatic sulfonic acid 0.2-0.3, refractory silica based filler — the rest. The introduction of a liquid mixture of organic salts of alkyl sulfuric and alkyl aromatic acids in a ratio of 1: 3 ensures synchronous solidification of the mixture and foam deposition in the mixture, which contributes to an increase in gas permeability and dislodgeability of the mixture. 2 tab. i SL x el 00

Description

The invention relates to foundry and can be used to make molds and cores. liquid self-hardening mixtures.

The purpose of the invention is to increase the gas permeability of the mixture and improve its knockability.

The proposed mixture contains a refractory filler, a binder, a hardener, a surfactant and water.

Quartz sand 1K0315A is used as a refractory filler, binder is liquid glass with a modulus of 2.8 and a density of 1.48 g / cm. Powder hardeners are used to harden the mixture: ferrochromic slag with a specific surface area of 2200 cm / g, nepheline sludge and portland cement „

A mixture of salts is used as a surfactant.

to

2.0 2.0 2.5 3.0 2.0

5.5 5.5 5.5 5.5 6.0

0.15 0.20 0.05 0.30 0.20 2.0 2.0 2.0 2.0 2.0 1,

90.35 90.1 89.75 92.2 91.8

55

From the prepared mixtures, the composition of the strength properties is carried out

Standard samples of the device of the Usmansky plant were manufactured using a 50 mm meter and a height of 50 mm for an unlawful GOST 23409.0-78, GOST 23409.5- compression strength test. - Definition - 78 - GOST 23409.9-78. Mixture flowability

alkyl sulfuric acid with the general formula SpN7pm CH (CH,) 050, Na, where n 6-12, and alkylaromatic sulfonic acids C, H, (OH) CH, C, H (OH), Na in the ratio 1: 3.

I

Mixing is carried out

in a paddle batch mixer with a horizontal mixing shaft at a rotation speed of p 60 rpm.

First, dry components are mixed for 2-3 minutes: quartz sand and hardener, then a liquid composition is introduced: liquid glass, water and surfactant and the mixture is stirred for another 1 minute, after which the finished mixture is released into a core box. The total mixing time is 3-4 minutes. Curing of the mixture occurs within 40 minutes in a snap and 3 hours in air.

The compositions of the mixtures are given in table. one.

Table 1

2.5

3.0 3.0

6.0

6.0 6.0

0.25 0.30 0.35 1.6 1.6 1.6:

89.65 89.1 89.15

31289580

determined by the diameter of the spreading; Bleedness of the mixture is determined by the cone. Cone sizes: upper ext - on residual compressive strength: early diameter 100 mm, lower intra - after calcination of the samples at 1000 ° C, the diameter of 200 mm, high. and cooling with the stove. The result of 300 mm.5 you tests are presented in Table. 2

table 2

Vitality (foam stability), min

Time to seize, min

Compressive strength, kgf / cm (9.8-10 Pa)

According to the test results, it was established that the content of surfactant in the mixture is between 0.2 and 0.3 May. %

The use of the proposed liquid self-hardening mixture for the manufacture of casting molds and cores improves gas permeability and improves disintegration of the mixture while maintaining a high hardening rate and optimum survivability, which, in turn, will reduce the loss of castings in gas shells, reduce labor intensity for knockout and cleaning operations will increase labor productivity and reduce the number of workers engaged in heavy physical labor.

15

14

12

ten

10 12

five

0

five

invention formula

Liquid self-hardening mixture for the manufacture of casting molds and cores, including silica-based refractory filler, water glass, a dicalcium silicate hardener, water, and an active substance from the alkylarylsulfonate class, which is designed to increase the gas permeability of the mixture and improving its knock-out while maintaining a high rate of hardening and optimum survivability, as a surfactant it contains a mixture of salts of alkyl sulfuric acid - with the general formula

5 12895806

, CH (CH,), where n is 6-12, Mixture of salts and alkylaromatic sulfonic acid of sulfuric acid, (OH) jCH, CtH ,, (OH) 2CH, J. acid and al in a ratio of 1: 3 with a slightly-aromatic ratio of ingredients, 5 kool sulfoxis May.%. lots with the mentioned chemical-liquid glass 5.5-6.0 m in formulas in the hardener ratio 1: 3 0,2- 0.3 on the basis of the tO refractory on the dicalcium filler on the vrgo silicate 2.0-3.0 on the basis of dioxide Water 1.6-2.0, the rest

Claims (1)

Claim Liquid self-hardening mixture for the manufacture of foundry molds and cores, including a refractory filler based on silicon dioxide, liquid glass, a hardener based on dicalcium silicate, water and a surface active agent from the class of alkylarylsulfonates, characterized in that, in order to increase the gas permeability of the mixture and improve it knockout while maintaining a high hardening rate and optimal survivability, as a surfactant, it contains a mixture of salts of alkylsulfuric acid with the general formula ^C Lpm CH (CH,) 0S0 ₃ Na, where η = 6-12, and alkyl aromatic sulfonic acid {[C _e Н, (0Н) ₂ CH /] [C _t Н _g (ОН) _g СН,] _g ] S0 ₃ Na в 1: 3 ratio in the following ratio of ingredients, May. X Liquid Glass Hardener 5.5-6.0 based dicalcium silicate 2.0-3.0 Water 1.6-2.0 Salt mixture alkyl sulfuric acid and al- 5 kylaromatic sulfoxide 10 lots with the mentioned chemical formulas in a ratio of 1: 3 0.2-0.3 Fireproof silica based filler Rest Editor I. Seglyanik Compiled by Shuvalov Tehred V. Kadar Corrector S. Cherni Order 7846/10 Circulation 763 Subscription VNIIIPI of the USSR State Committee for Inventions and Discoveries 113035, Moscow, Zh-35, Raushskaya embankment, d. 4/5 Production and printing company, Uzhhorod, st. Project, 4