The processing of friable materials used in metallurgical industry for production of definite size classes requires operation of crushing machines, including single-roll machines. Parameters of crushing process are degree and efficiency of crushing. The crushing degree is estimated by the ratio of dimensions of the initial crushing and resulting pieces and depends on the size of gap between the roll and the fixed jaw. Crushing efficiency is determined by mass of material crushed by consumed electric energy unit, and depends mainly on strength of crushed material. In order to reduce energy consumption needed for crushing, a single-roll crusher was developed at Siberian State Industrial University with forced feeding of crushing piece into the fracture zone due to the locker located on the roll. Forces of technological resistance appearing during machine operation are the main initial values for machine drive power and structural elements strength testing, thus, the operation power analysis is an integral stage in the design of any machine, including a crushing one. In the present work, forces acting on a crushing piece from roll side and fixed jaw in vertical and horizontal planes are identified. Based on the results obtained, it was determined that internal compressive forces acting on piece of crushing material cause action of normal compressive stresses in a piece, as well as an internal torque effect, which causes shearing stresses action, i.e. a complex stress state is generated in a fractioned piece with simultaneous action of normal and shearing stresses, under which action a fractioning piece is destroyed. Thus reduction in energy consumption for crushing is achieved, with all other conditions being equal. It reduces energy consumption of a single-roll crusher with forced feeding of material into the crushing zone.

The description of crusher design is given, in which the destruction of the processed material occurs due to the forces acting on the crushed piece in the same plane towards each other, while in the processed piece only tangential stresses arise. It makes possible to reduce the energy consumption per unit of finished product by almost two times.

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Епифанцев Ю.А., к.т.н., доцент кафедры технической механики и графики Демина Е.И., аспирант кафедры транспорта и логистики Сибирский государственный индустриальный университет (654007, Россия, Кемеровская обл., г. Новокузнецк, ул. Кирова, 42) Аннотация. Предложена методика расчета усилия резания на ножницах предварительно изогнутой полосы. Определено, что при резке предварительно изогнутой полосы максимальное усилие резания меньше, чем при резке прямой полосы.

Current trends in the development of metal forming methods are considered. Along with the increase in production volumes, the tasks of quality improvement, expansion of the product mix and energy costs reduction are becoming more and more important. To solve the set tasks, the most promising methods are combined processing, such as rolling-pressing, casting-rolling-pressing. The combination of different processing methods in one process allows conditions for the production of new profiles to be created, energy consumption to be reduced. However, the lack of sophistication of the issue in theoretical terms, the few experimental data make it difficult to find optimal modes of shaping and layout of equipment when combining processing methods. To determine the energy-efficient conditions of the rolling-pressing process, the rational layout of the equipment, new dependencies are proposed. Conducted analytical studies have proved that when implementing the rolling-pressing process for each deformation condition in the roll-matrix system, there is an optimal matrix installation location that provides the maximum drawing coefficient with minimal energy consumption. The feasibility range of the combined rolling-pressing process was established, energy-efficient deformation modes were determined, taking into account the design features of the deforming unit and the shape parameters. Recommendations for the rational layout of the deforming unit equipment, carrying out the rolling-pressing process were developed.