Calculation of the productivity of a single-roll crusher with forced feeding of the destroyed material

Abstract

The high growth rates of metallurgical production lead to an increase in the use of mineral raw materials necessary for conducting metallurgical processes. In almost all metallurgical processing, crushed brittle material is required as a feedstock, obtained using crushing machines, which are also used to process the resulting products of metallurgical processing: slags, ferroalloys and others. The design of an energy-efficient single-roll crusher with a roll stop is considered, in which the destruction of the initial piece occurs due to the creation of a complex stress state in the mate-rial. The creation of such a stressed state in the material being destroyed helps to reduce the energy consumption for crushing compared to crushers working on compression by 60‒70 %. A distinctive feature of such a crusher is the forced supply of the destroyed material to the crushing zone. In case of forced feeding of the loaded material, the per-formance evaluation is determined by the volume of the loaded material per unit of time. This is due to the fact that the loading of the initial pieces is carried out discretely. The developed methodology for calculating productivity is based on the condition that a loaded volume of material consisting of pieces of a given initial fraction is processed in one revolution of the roll. The size of the initial piece fed into the crushing zone is determined from the considerations that the size of the initial piece should be larger than the gap that sets the size of the finished fraction, while the working surface of the stop contacts the crushed piece at a point located on a tangent drawn from the center of the roll through the extreme point of the piece. In the limiting state, the upper edge of the working surface of the stop contacts this point, in this case, the size of the initial piece reaches its maximum value