Refractory concrete parts for edging the walls of soaking pits

Abstract

At present, in the majority of steel plants of the country the upper structure of the walls of soaking pits is laid manually of 4-6 rows of chamotte brick and the remainder of the walls of large silica blocks and panels, the life of which is 8-12 months [i]. The edge is subject to mechanical action and thermal shocks, which leads to failure of the monolithic lining, a reduction in service lives to 2.5-3 months, and a sharp decline in sanitary and hygienic working conditions in the shop.There have been positive results of tests of edges of aluminosilicate concrete with a high alumina filler, high alumina cement* [2], and clay--phosphate binder [3].This article presents the results of production and testing of concrete parts with the use of production wastes [4].The experimental parts for the soaking pit wall edge were produced in the Khristoforov Refractory Block and Concrete Plant.Scrap from silicon carbide parts (86.68% SiC, 12.06% Si02, 0.15% C), bauxite (68.32% Al2Os, 3.58% Fe203), and commercial grade chamotte (31.15% AlaOs) were used as the filler of the concrete and high-alumina and alumina cements as the binder.The use of bauxites as fillers for refractory concrete is assumed to be possible with not more than 5% Fe203 in it.The original materials (with the exception of 20-0-mm fraction ground bauxite obtained from Borovichi Refractory Compound) were ground in an SM-741 jaw crusher and then in an OTsD-50 cone mill.The pulverized materials were separated into the 20-5-and 5-0-mm fractions (Table i). The mixture was mixed in a cement mixer.The parts were produced from plastic mixtures by the vibroforming method.+ The compositions of the mixtures are shown in Table 2.The mixtures were compacted with IV-47 deep vibrators a total of 12 parts of special configuration ( Fig. i) with a weight of 4.8 tons was prepared.