SU1694540A1 - Stone castings - Google Patents

Abstract

The invention relates to the production of stone products intended for the protection of metal structures and apparatus operating in conditions of elevated temperatures, abrasive wear and corrosion. In order to increase the refractoriness of the stone cast contains, wt.%: SI02 46.0-55; A | 2Oz 9-15; ReaOz 0.2-5.5; FeO 0.5-7; MpO 0.1-0.8; MDO 10-18; CaO 12-22; Na20 0.1-2; K2O 0.1-0.8: Cr20z 1-3: NiO 0.01-0.10; Tyu2 0.2-2; 2g02 0.1-1. Stone casting has a compressive strength of 590-635 MPa, wear resistance of 0.10-0.20 kg / m2, heat resistance of 1030-1080 & C, acid resistance in 20% HCI is 99.6-99.8%, in concentrated 99.9%, the temperature of onset of deformation is 1210-1260 ° C, the heat resistance temperature is 1240-1280 ° C, and the flow temperature is 1290- 1320 ° C. 1 tab.

Description

(L

WITH

The invention relates to the manufacture of stone products and can be used to protect metal structures and apparatus from abrasive wear and corrosion, operating under conditions of elevated temperatures.

Known stone casting, including, wt.%:

Si02 50-60; 4.5-10; Re203 0.1-1; FeO 0.1-1.5; MDO 17-21; CaO 10.2-14.7; Na20 0.5-2.5; K20 0.2-1; Сг20з 0.03-0.9; MpO 0.2-0.5; ZnO 0.15-1.5

and one oxide from the group: CoO 0.3-3; NiO 0.3-3.

Known casting has insufficient refractoriness

Known stone casting, including, wt.% Si02 40-47; 9-14, FeO 1-2: Fe20s 3.6-5; CaO 18-23; MDO 6-9; Na20 0.3-0.5; K20 1-2; MpO 0.05-0.15; Cr203 1-2; 50zO, 1- 0.2: CI 0.5-2; N10 0.4-0.86; CCO 0.06-0.19.

Known casting is characterized by obtaining a homogeneous fine-crystalline dense material whose initial phase are spinellides of complex composition, and the main phase is pyroxene-based solid solutions. Such a crystalline structure causes a low refractoriness of the material.

The purpose of the invention is to increase the refractoriness.

This is achieved by the fact that stone casting, including Si02, A120z, Re20z, FeO, MpO, MgO, CaO, No. 20, K20, CrOg NiO, additionally contains TG and Zr02 with the following content of components, wt.%

ABOUT

J

with

yo

SiOa 46-55; TI02 0.2-2; 9-15; Re20z 0.2-5.5; FeO 0.5-7; MnO 0.1-0.8; MgO 10-18; CaO 12-22; Na20 O.V-2; teO 0.1-0.8; CrSoz 1-3, N100.01-0.1; Zr02 0.1-1.

The introduction of the complex additive ZrOa in an amount of 0.1-1 wt.% And TiO2 in an amount of 0.2-2 wt.% In petrurgic melts containing MgO and AlaOa, reducing the solubility of Zr02 in glass, causes an increase in the catalytic effect and leads to a decrease ( less than 10% of the glass phase in the material. In the presence of a glass phase greater than 10%, the refractoriness of glass-ceramic materials is determined by the composition of this glass phase. In the well-known casting, the refractoriness of the material depends on the phase composition and habit of the crystalline formations that make up the stone cast,

Introduction of less than 0.1 wt.% And less than 0.2 wt.% Of TiO2 into the Zr02 melt does not provide a sufficient increase in the refractoriness of the material, since the content of the glass phase in the material exceeds -10 wt.%, And the concentration of Zr02 in the glass phase does not exceed 1 wt. %

Zr02 content of more than 1 wt.% Leads to surface crystallization of pyroxene materials, which adversely affects the physicochemical properties of castings due to the heterogeneity of the structure across the thickness of the casting (micro-crack and microporosity may develop on the surface of the product).

The content of TI02 more than 2 wt.% Leads to an increase in the crystalline ability of the melt, an increase in the crystals of the main phase - pyroxenes and the development of shrinkage porosity, which leads to a decrease in the mechanical strength of the material. The presence in the composition of 10-18 wt.% MgO and 0.1-0.8 wt.% K20 causes the formation of the maximum amount of solid solutions based on pyroxene - the main crystalline phase.

The MgO content is more than 18 wt.% And the K.20 content is less than 0.1 wt.% Leads to the intensive growth of pyroxene crystals. At the same time, the shrinkage porosity and the size of the material increase, which significantly reduces its strength and performance properties.

The MgO content of less than 10 mAc |% and more than 0.8 wt.% Leads to a decrease in the crystallization capacity of the melt and a sharp increase (more than 10%) of the glass phase, which causes a decrease in the refractoriness of stonestone material.

The compositions and properties of the known and proposed casting are presented in the table.

Sand, dolomite, clay, as well as igneous rocks, the battle of chromo-magnesite brick and baccore are used as raw materials for obtaining the proposed stone casting compositions.

The mixture is boiled at 1500 ± 20 ° С. The finished melt is produced into earth forms in the usual way, adopted in the stone foundry industry. The crystallization of the material is carried out at 950-970 ° С for 30 minutes.

The proposed composition of stone casting provides for the preparation of pyroxene anchomonomineralite stone material composed of coarse-grained, tangled-fiber structure of uniform thickness and containing no more than 10% Zr02-enriched glass phase. This material is characterized by high temperatures of onset of deformation (1210–1260 ° C), heat resistance (1240–1280 ° C), and flowability (1290–1320 ° C), which determine the refractoriness of the glass-ceramic material (stone cast) —the ability to withstand without deformation heating to a certain 5 temperature.

The proposed stone casting is recommended to protect metal structures and apparatus from abrasive wear and corrosion, operating under conditions of high temperature (up to 1100 ° C) or sudden temperature changes (950–20 ° C), for example, for lining coke ram extinguishing bunkers agglomerations, etc.

The economic effect of the application

5 of the proposed stone cast as

agglomeration bunkers lining instead

is 20-25 rubles. per 1 t stonestone

products by increasing the service life

by 1.2 times and reducing the cost of repairs.

Claims (1)

Invention Formula Stone casting, including SiO2,, Fe203, FeO, MnO, MgO, CaO, Na20, K20, Cr203, IMO, characterized in that, in order to increase the refractoriness, it additionally contains TiO2 and Zr02 in the following ratios of components,% in May Si0246-55 And 20z9-15 0Re20s0,2-5,5 FeO0,5-7 MnO0,1-0,8 MgO10-18 CaO12-22 5Na200,1-2 K200.1-08 SG2031-3 NiO 0.01-0.1 TI020,2-2 Zr020,1-1 Compiled by M.Nedoseeva Editor T.Gor chevaTehred M.MorgentalKorrector T.Kolb Order 4125 Circulation. . Subscription VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, 4/5 Raushsk nab. Production and Publishing Combine Patent, Uzhgorod, Gagarin st., 101