SU1145005A1 - Refractory compound - Google Patents

Abstract

REFRACTORY MASS for restoring the rear wall and mercury of open-hearth furnaces, including magnesium oxide, chromium oxide, calcium oxide, coal tar pitch, characterized in that, in order to increase the resistance of the applied refractory layer, oia contains components in the following ratio, wt.%: Oxide chromium8-18 Calcium oxide 5-15 Coal coal 6-8 magnesium oxide Else

Description

 A1 The invention relates to metallurgy and can be used to restore the masonry of metallurgical aggregates. A refractory mass is known, which includes magnesium, chromium and titanium oxide in the following amounts, wt.%: Magnesium oxide 63-87 Chromium oxide 10-30 Titanium dioxide 3-7 However, weak mass fixing on the inside of the kiln lining due to the absence of a ceramic bond , reduces the caking with the main lining. In addition, insufficient metal resistance leads to a decrease in the resistance of the applied fire resistant layer. Closest to mischief. are refractory masses containing magnesite, dolomite, chromomagnesite or mixture and, as a binder, cameo coal pitch (l-309fc 12). {The wealth of a known mass is the low resistance of the coating made from it. The purpose of iz tenn - increase the resistance of the applied refractory layer. The goal is achieved by the fact that the refractory mass for the restoration of the rear wall and the slopes of open-hearth furnaces, including MartffIH oxide, chromium oxide, calcium oxide, stone peg, contains components in the following ratio, wt.%: Chromium oxide. . Oxide kalitsh Kamyuuguolny pitch Else Oksana magnesium The content in the mass of coal tar pitch in the amount of 6-8 wt.% Is due to the production of a high-temperature binder, which in the process of burnout forms a solid ceramic binder with the main lining of the furnace. Reducing the content of coal tar pitch to less than 6 wt.% Leads to a decrease in the ceramic bond with the main lining of Aechi, and an increase of more than 8 wt.% Increases the plasticity of the mass in the process of applying it to the hot lining and leads to a decrease in the covering power of the mass. The content in the mass of calcium oxide in the amount of 5-15 wt.% Is due to the formation of the ceramic state of the mass at high temperatures of 1400-1600 C. A decrease in the calcium oxide content of less than 5 wt.% Leads to the formation of a porous structure, a refractory mass in a hot state, and an increase of more than 15 May. % - to reduce the refractoriness. The content of oxime chromium in the amount of 8-18 wt.% Due to slag-resistant mass. A decrease in the content of oxime chromium of less than 8 wt.% Leads to a decrease in resistance to wear, and an increase in more than 18 wt.% Leads to a decrease in refractoriness. The content of magnesium oxide is due to the refractoriness of the mass at 1400–1800 ° C by the low chemical activity with the metal. In addition, the magnesium window increases the metal stability of the mass. The refractory mass is prepared by mixing the consumable components in the required amounts. The prepared mass is applied using a filling machine to the back wall and slopes of the open-hearth furnace at 1400 -1600С. The mass is well attached to the worn areas of the kiln lining. In the process of operation, the furnace is not washed away with slag and Metal. C) 1st metal release in the kiln at 16001400 s a refractory mass is applied to a worn lining with a ribbon-type filling machine, the compositions of which are shown in the table. As can be seen from the table, the resistance of the refractory coating. increased to 27 heats, while when applying a refractory mass based on magnesite-chromite with Cr Oj content 8-1 8% with the addition of 8% pitch, the slag and metal were washed away, which led to a decrease in the resistance of the applied refractory coating to the lining height ovens.

Coal tar pitch

15

ten

Calc Oxide {

sixteen

Magnesium oxide 8171

59

M inesitochromite with CrjO content,

2527

2420

Swimming trunks

8456

84

80

74

12

18

18

22

21

20

Claims (1)

Refractory mass for the restoration of the back wall and slopes of open-hearth furnaces, including magnesium oxide, chromium oxide, calcium oxide, coal tar pitch, characterized in that, in order to increase the resistance of the applied refractory layer, it contains components in the following ratio, wt.%: Chromium oxide 8-18 Calcium oxide 5-15 Coal tar pitch 6-8 Magnesium oxide Rest SI ί145005