SU1130553A1 - Refractory composition for hot overhaul of carbonaceous lining - Google Patents

Abstract

REFRACTORY MASS FOR A HOT. REPAIR OF CARBON-CONTAINING FUTE-. ROVKS of thermal units, containing a refractory filler, refractory clay, coal tar pitch and water, characterized in that, in order to increase the adhesion strength during gunning repairs, it contains fireclay as a refractory filler at the following ratio of components, wt.%: Refractory filler 10–30 clay C ameno y – 5–5 baked pitch Water 1–5. S Rest Chamotte CO

Description

The invention relates to refractory industry and can be used for hot repair of carbon-containing materials and heat exchanger linings for hot repairs, in particular, to the cast iron discharge chutes of blast furnaces. A known refractory mass for gunning the lining of thermal units, containing, in wt.%: Refractory filler 65-85; liquid glass 7-14; orthophosphoric acid 3-6; burned rock coal mines 5 15, However, such gunning mass is not suitable for hot repair of carbon-containing linings due to poor adhesion and weak coupling with the lining, because water solutions of liquid glass and phosphate, included in the composition of the mass, do not wet carbon materials. A disadvantage of the known refractory mass for gunning is also a high humidity (more than 10%), which increases the drying period. It can exceed the period between two adjacent outlets of pig iron from the blast furnace. Closest to the invention of the technical essence and the achieved result is the mass used for the filling of the blast chutes, containing, in wt.%: Refractory clay 20; coal peck 15 water 15, refractory aggregate (coke) else, The composition of the mass includes a clay-pekovy bond, which at high temperatures wets the surface of carbon-containing materials z, However, when applying a known mass by spraying onto a hot surface, the latter moisture content of the mass is significantly cooled to temperatures that do not allow the pitch link of the mass to fully soften, which causes poor adhesion of the mass at the time of its application to the lining, and in the further unstable coupling ix shotcrete layer lined, generally, reducing its resistance. In addition, the high moisture content of the mass does not allow the creation of a layer of coating of the necessary large areas (50,200 mm) due to the creep of the mass from the surface. The known packing weight is low-tech when shotcrete, since due to high humidity it is poorly transported through the hoses of existing gunning installations. In addition, the presence of a significant amount of moisture requires physical drying, the duration of which exceeds the time between the release of iron from the blast furnace. The purpose of the invention is to improve the adhesion strength during gunning repairs,. The goal is achieved by the fact that the refractory mass for hot repair of the carbon-containing lining of thermal units, containing refractory filler, refractory clay, well, coal tar pitch and water, contains fireclay as the refractory filler in the following ratio of components, wt.%: Refractory , clay10-30 Coal-tar pitch 5-20 Water1-5 Fireclay Rest The refractory gunning mass has less moisture compared to the known mass, therefore when applied to the hot surface of the repaired lining EHD slightly cooled to gemperatur which permit posted gchits peko- howling component, which wets the surface of the carbon-containing liner, a result of an applied shotcrete mass adheres well to the liner and firmly engages with it, thereby forming a cooling trench kamnevydnoe resistant coating. Good adhesion of the sprayed mass at the time of its application to the surface of the lining eliminates mass creep when creating coatings of 50–200 mm thick. Due to the low humidity, the mass is well transported through the hoses of existing gunning installations, and the coating applied to the lining of the groove does not require additional drying. Example, Masses, the compositions of which are given in table. 1, is prepared by mixing the starting materials in the mixing runners with their further moistening. Cooked sprayed nano- mass. with t with the help of a type 3 gunning machine, BM-60 on a vertical wall heated to 500 + 20 ° C, consisting of a carbon-holding mass, used for tamping blast furnaces, the value of the adhesion of the applied coating is estimated by the percentage of mass adhering to the wall surface, to the initial amount of the mass applied to the wall. The determination is carried out by weighing. The adhesion strength is estimated by the shearing force of the coating on the surface of the carbon-containing lining. The determination was carried out according to the well-known methodology h). The test results are given in Table 2. The use of the proposed gunning mixture helps to reduce labor costs for the repair of the iron discharge channels 1.5-2 times and reduce the consumption of lining material. The economic effect from the application of the invention at the metallurgical plant will be 300 thousand rubles. Table 1

The relative amount of gunning mass j stuck to the surface in% of the source water

1 3 5

15

50

table 2

30 0.05

Claims (1)

FIRE-RESISTANT MASS FOR HOT REPAIR OF CARBON-CONTAINING FOUT-. FUNCTIONS of thermal units, containing refractory filler, refractory clay, coal tar pitch and water, characterized in that, in order to increase the adhesion strength during repair by shotcreting, it contains chamotte as a refractory filler in the following ratio of components, wt.%: Refractory clay 10-30 Kamenno y golny pitch Water Fireclay 5-20 1-5. Rest