At present the torch guniting method has found wide use for repair of the linings of metallurgical equipment but its use may be significantly broader.The possibility of creation of a flame with a temperature close to the melting point of the refractory and the presence of high velocities of gas flow with suspended refractory particles makes this method suitable for the production of parts with high servlcecharacterlstics.The advantages of the method are obvious since it makes it possible to greatly reduce the capital expenditures for the production of refractory parts and also to reduce the time for placing in service of facilities for the production of refractories with a simultaneous increase in their quality characteristics.Plans of equipment for the production of refractory parts are given in [i, 2]. Each of the pieces of equipment includes a guniting torch operating with oxygen and liquid or gaseous fuel, a chamber feeder supplying powdered refractory material to the gunitlng torch, and a support placed in the furnace.In operation of the equipment the refractory powder, delivered through the gunlting torch, having fused, forms on the base, forming the refractory part. In order to eliminate the formation of cracks after completion of the forming process the part is slowly cooled in the furnace. This method of production of parts makes it possible to control their microstructure during production, which in turn makes it possible to create refractories with high purity, high temperature strength, and heat resistance.The porosity of parts produced by this method is from 0 to 60% in different cross sections depending upon the increase or decrease in the consumption of gas supplied through the guniting torch.Using the torch guniting method it is possible to produce parts not only of oxides of high purity and refractoriness (AI=O,, Ti02, MgO, etc.) but combined ones consisting of materials of different properties.In [3] data is presented on investigation of the microstructure of an AI20, ceramic produced by this method. It is shown that the size of the corundum crystals in the ceramic depends upon the conditions of spraying of the specimen. For example, with an oxygen consumption of 0.631 mS/h and a rate of spraying of 30 mm/h the crystal size did not exceed 35 ~m. With an increase in oxygen consumption and a decrease in the rate of spraying the grain size increased to 80-100 um.An increase in the gas consumption caused intergrowth of the individual single crystalline rods and the formation of a continuous skeleton of the single crystalline part.This method makes it possible to broaden the area of use of aluminum oxide parts as the result of obtaining high purity material. Such parts possess increased strength, refractoriness, and resistance to thermal shock.An example is vessels for melting of phosphate glass produced from refractories manufactured by this method. The service llfe of such vessels is one to eight times greater than those of fused quartz.Let us present the results of tests of corundum tubes produced...

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