Using slag-forming materials for flame guncreting of converter linings

Application of refractory slag-forming coatings to the lining of converters

“…Therefore, for the refractory slag-forming coating process it is not necessary to prepare special lime but that which is supplied to the shop for melting may be used [6].…”

“…According to a technical program of the All-Union Institute for Refractories the Azov Steel, Western Siberia, and Cherepovets Metallurgical Combines have been equipped with and are using equipment for the production of lime guniting mixtures [5,6,16]. At the Western Siberia Metallurgical Combine the equipment is located in the refractory facility and serves two converter shops.…”

“…The first is intensification of the processes of combustion of the flame for the purpose of increasing the life of the periclase coatings [I], and the sec ~ ond is conversion to guniting with inexpensive and readily available materials (primarily lime) for partial or complete replacement of periclase powders in guniting mixtures [5,6].The first direction is accomplished in the following manner.By selecting the forms of fuel [I, 7] or by changing the design of the heads of multinozzle guniting guns [4,8] a reduction in coating porosity is obtained.However, with packing the periclase coating starts to spall and therefore additional measures for elimination of thermal failure of gunited coatings become necessary.These include additions to the guniting mixture of slags and oxides of iron [i] or aluminum [2] or guniting with thin layers [3]. The latter measure is not always possible under the conditions of organization of work in converter shops, and additions of oxides lead to a reduction in the slag resistance of the applied layers.…”

“…The latter measure is not always possible under the conditions of organization of work in converter shops, and additions of oxides lead to a reduction in the slag resistance of the applied layers. Until now there have been no examples of a positive solution of this problem on a production scale~The second direction in improvement in torch guniting is accomplished by application to the working surface of converter linings of refractory slag-forming coatings.This process was developed by the All-Union Institute for Refractories and by the Azov Steel, Western Siberia, and Cherepovets Metallurgical Combines.The fundamentals of the new process are that a lime coating in a converter is refractory and at the same time it is used for refining of the steel and there is a reduction in the addition of lump converter lime and the share of hot metal (as a result of the increase in the share of scrap) to the heat by a value approximately equal to the weight of the applied lime coating or of its soluble portion if the coating does not wear during a single heat.The basic stages of formation of refractory slag-forming coatings were described by us earlier in simplified form [6]. The kinetics of the processes which occur in sintering of powders in tne presence of a liquid phase depend significantly upon the size of the particles being sintered, the quantity of liquid phase, the degree of wetting of the solid phase by the liquid, the mutual solubility of the phases, the porosity of the particles, and the density of their packing [9].…”

Use of torch guniting for the repair and protection of the linings of aluminum production equipment

“…high productivity of up to i000 kg of applied compound per minute; the capability of making hot repairs of operating equipment, which leads to prolongation of their campaign by several times; the organic technological effectiveness of the process in repair of steel melting furnaces; the constituents of the guniting compound are necessary components in melting of the metal; the use as the guniting compound of secondary inexpensive raw material such as coke dust, scrapped refractory parts, slag forming materials, etc. [5][6][7]; the capability of multiple repretition of the repair cycles.…”