The paper analyzes the properties of rocks with a shale structure, justifies the need to apply force in the direction of the lowest strength. The list of crushing equipment used in the process of obtaining cube-shaped crushed stone is given. It is established that the existing crushing equipment is not able to take into account the specific texture of the crushed materials and this does not allow obtaining cube-shaped crushed stone from shale materials. A description of the new design of the press-roll unit, which allows obtaining cuboid crushed stone from rocks with a shale structure, is given. The press-roll unit includes a device for directional feeding of shale materials to its working bodies, which create a force effect on the fed pieces of rock in the required direction. The design of the tooth of the working body is described, which allows to reduce significantly the replacement time of worn elements and reduce the bending loads acting on it. This leads to an increase in the reliability of the structure and reduces the metal consumption of repairs. A mathematical model of the directional movement of shale materials in a roll device is considered and an equation for calculating the required force is obtained. Graphical dependences of the influence of the roller installation angle and its horizontal and vertical displacement on the amount of deformation of the feed material layer are presented.

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The article presents the results of experimental studies on the grinding process of a clinker preliminarily ground in press roller mills in a ball mill equipped with energy exchange devices. The authors studied the influence of the coefficients of loading for grinding bodies of the first and second mill chambers, their lengths, angles of inclination, and the mutual location of energy exchange devices (the ellipse segment and the double-acting blade) on the output parameters of the grinding process (productivity, drive power consumption and specific energy consumption). It is clarified that the best results of the disaggregation and grinding process, judging by the minimum specific energy consumption in the grinding of clinker with an anisotropic texture after force deformation between the rolls of a press roller shredder, are achieved at a certain angle of ellipse segment inclination; the length of the first chamber and the coefficients of loading the chambers with grinding bodies.

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The improvement of methods and technologies for the production of dry building mixes, dispersed modifiers, dry paints and other finely ground, homogeneous systems is associated with the quality of their compositions, which, in turn, requires the use of high-tech energy-saving equipment. The use of the original pneumatic mixers proposed in the paper makes it possible to obtain high-quality multicomponent mixtures due to the specially organized movement of the two-phase flow meeting with the peripheral supply of the energy carrier. Forecasting and analyzing the dynamics of two- and multiphase systems distributed in the air in units of this type allows assessing the nature of the technological process of mixing components, while a mathematical description of the complex movement of particles in the air flow allows obtaining a result that helps to characterize the operating modes of the pneumatic mixer, which is important when operating this machine in production. The paper presents a method for numerical simulation of the axisymmetric motion of a two-phase flow in the homogenization chamber of a pneumatic mixer, which allows setting adequate operating modes of the unit for various dispersed systems mixed in it. The main assumptions in the construction of the mathematical model are also reflected, the conditions for setting the problem for this study are formulated, and the results are obtained in the form of analytical expressions of the main dynamic parameters of the flow with particles for the volume of the mixing chamber, depending on the design features of the pneumatic mixer.