East Institute Refractories (Russia)

New periclase-spinellide refractories of grade PShSKh have been developed based on melted periclase with 97% MgO and synthesized chrome spinellides.

The movement of a fluid medium of constant density in cylindrical and conic channels -- analogs of the operating space of continuous reactors of industrial power plants -- is considered. Special and generalized formula are derived that relate fluid parameters to the geometry of cylindrical and conic channels; properly modified, the formulas can be used for a design analysis of the reactor's operating space. An example of design formulas is given.

The technology and commercial production of periclase-carbon articles with a regular grain composition from a raw material with unstable grain size are described. A comparative study of casting, elemental, and crucible graphite as the basic carbon component has shown that the best commercial properties are provided by the use of crucible graphite. Tests of periclase-carbon refractories without metallic aluminum and with various contents of aluminum have shown the possibility of a differentiated approach to the use of the antioxidant with allowance for the specific service conditions of the lining.

Technological tests of Malinovetskoe kaolins have shown that mixtures with these kaolins in the binder give chamotte refractories with a porosity of 19–24%. Denser articles can be produced with the addition of sintering clays such as Novoraiskoe or Nizhne-Uvel’skoe, by the method of joint milling, or with an additive of finely milled chamotte

The effect of the mineral and grain composition of charges and the manufacturing technology and characteristics of vibroshaping of low-cement thixotropic castables having an alumosilicate and a corundum composition on the physicochemical properties of the obtained material are considered. Experimental refractories fabricated of low-cement castables have been tested in intermediate ladles of a continuous casting machine. The developed low-cement thixotropic castables possess high physicomechanical and operational properties and can be used in various metallurgical equipment.

Based on the molding of experimental samples from a dinas mixture and the determination of the apparent density of the samples calculated for the solid phase, we have established the values of the parameters of the compressibility equation, taking into account the residual and elastic deformation of the compact. Values of the molding pressure corresponding to the limiting density in the transition from a three-phase to a two-phase system have been determined as a function of the height of the mixture fill in the mold.

Using data of S. T. Balyuk, a square-law nonlinear dependence of the density of a liquid process binder on the content of dry substance is established. The parameters of the equation derived are determined. The method can be used for other liquid binders and permits determination of the content of dry substance as the solution of the aforementioned equation.

Methods for determining the gas permeability of porous bodies are considered. The gas permeability of pressings from chamotte mixtures with different moisture contents and compositions is determined experimentally. The empirical dependence of the gas permeability of a pressed specimen on the pressing pressure is shown to have the form of a decreasing exponential. The parameters of the exponential are determined for various mixtures. Comparative curves of the gas permeability and the gas content are plotted in a wide range of pressing pressures.

Ways to calculate the fraction of dust caught in firing raw materials are presented in the form of formulas. It is recommended that in using the results the method by which they have been obtained be indicated.

Work on creating a refractory mixture of a base composition for consumable linings of tundish ladles of continuous casting machines is described. Various binders for mixtures deposited on the working lining of the tundish ladle by guniting have been tested. The endurance of a consumable lining based on periclase with an elevated content of CaO was 5 heats on a CCM of an electric steelmaking shop.