The corrosion resistance of samples made of low-cement concrete to a bottle glass melt was investigated in dynamic conditions at a temperature of 1350°C; they are used for production of articles used in glass-forming machines.The domestic refractory industry does not fully satisfy the needs of the glass industry with respect to the assortment and quality of most of the refractories manufactured for glass-melting furnaces [1 -3]. For this reason, glass works use furnaces in conditions of lower (sometimes by 1.5 -2 times) output of glass melt from the melting area or to increase output, purchase foreign high-quality refractories which are several times more expensive than the domestic analogs, which affects the cost of the products manufactured.The quality of the refractories in direct contact with the working media in the glass-melting furnace (roof, walls, bottom of the melting part, etc.) plays an important role in ensuring high-quality glass products. In addition to the refractories in the melting zone, the articles in the production part (feeder elements and glass-forming machines), which have a complex configuration with elevated requirements both with respect to performance characteristics and with respect to shape and size as a function of the application, have a large effect on quality. During their lifetime, refractories are exposed to the intensive effect of the glass melt and important thermal and mechanical stresses, so that they must have high glass and thermal stability, strength, and must also provide for constant assigned parameters of feed of the glass melt for processing and its temperature homogeneity [4].The production channel or feeder channel directly adjacent to the working part of the tank is designed for feeding glass melt to the feeder and then processing it by the glass-forming machine. The temperature of the glass melt in the feeder channel is 1000 -1350°C as a function of the type of glass. The concrete temperature is established to ensure a uniform decrease in it to the level determined by the viscosity of the glass melt required for forming. Defects in the form of stone, ripples, and seeds that enter with the glass melt and appear in reaction of the glass melt with the refractory lining cannot be assimilated directly in the channel by the glass mass. For this reason, the refractories for lining the feeder channel must satisfy certain requirements; the basic requirement is slow, uniform dissolution in the glass melt without formation of any defects.Many requirements are imposed on refractories used in glass-melting furnaces; the most important one is corrosion resistance to the glass melt (glass resistance) [5 -7]. The glass resistance, characterized by the rate of dissolution of a refractory in a glass melt, is a function of many factors: the chemical and mineral compositions and the structural features of the refractory, the chemical composition and viscosity of the glass melt, the surface tension on the boundary of the glass and the refractory, etc.In the domestic scientific and te...

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Physicotechnical properties are provided for concretes based on mechanically-activated phosphate suspensions previously modified with magnesium and aluminum hydroxides and silicic acid. The results obtained demonstrate the efficiency of using modifying additions in order to increase the strength and heat resistance of corundum concretes. Development and improvement of the manufacturing technology for refractory materials using phosphate binders has promoted high physicotechnical and engineering properties for these refractories, strong adhesive bonds between particles of the filler within them, simplicity of production, not requiring significant energy and capital expenditure.Analysis of results of studies in the field of forming the material structure, the technology and properties of refractory concretes based on phosphate binders has revealed the efficiency of their use. Use of phosphate binders makes it possible to prepare high quality components [1]. Of the many forms of refractory concretes the best properties are exhibited by corundum concretes based on orthophosphoric acid, magnesium-and aluminophosphate binders. With the optimum content of 80% H 3 PO 4 these concretes after heat treatment at 800°C have high strength (ultimate strength in compression 60 MPa) and the greatest heat resistance (>50 thermal cycles). Addition of 9 -40% alumina hydrate does not improve the properties of corundum concrete, the strength is reduced, and there is an increase in its shrinkage and porosity. Corundum concretes based on magnesium phosphate binders with addition of 10% raw ground technical grade alumina are distinguished by high apparent density, strength and heat resistance [1].The properties and operating characteristics of corundum refractories are improved by introducing into their composition small amounts of modifiers [2]. In refractory concrete technology based on phosphate binders there is use not only of orthophosphoric acid, but also mechanically activated binding suspensions with different modifiers. Here a combination of mechanical activation and chemical reaction markedly improves the strength of castings with an increase in concentration of the phosphate-ion in the surface layer of corundum crystals [3].Mechanical activation of corundum charges with heat treatment at 180°C of an aluminoborophosphate binder reduces open porosity to 23% and increases the ultimate strength in compression to 115 MPa for corundum concretes after firing at 1300°C [4].The hardening mechanism for refractory concrete mixes based on phosphate binders is quite complicated. Within them there is chemical reaction of phosphates with the filler, polymerization and polycondensation, and also adhesion [5]. Here hardening processes change from chemical reaction of phosphate binders with the surface of filler grains to their simple adhesive gluing. Hardening of the main oxides (MgO, BeO, Y 2 O 3 ) is due to primarily to their chemical reaction with phosphate binders that leads to formation of new chemical compounds. The hardening mechanism f...

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