Technique for calculation of parameters of the wave profiled roll crusher for obtaining the cubic shaped products

Abstract

The purpose of this work is to develop a technique for calculating the crusher with wave profiled rolls based on analytical and experimental data on hard rocks processing in crushers of this type. Information on the expediency of using cubic-shaped products as fillers for concrete is given. Attention is focused on the advantages of this approach. The main types of equipment capable of producing the stone products with minimum content of lamellar pieces are analyzed. The choice of crushers with wave profile of rolls for processing of narrow-sized crushed stone fractions as combination of high efficiency with acceptable wear of working surfaces and low dynamics of working modes is justified. The algorithm of calculating the crusher parameters is given based on theoretical conclusions and experimental data on the fine crushing of hard rocks from open pits of Ukraine on the real sample of crusher with wave profiled rolls. Granulometric characteristics of narrow-sized fractions, based on the results of material screening using slits with round and slot openings, the yield of lamellar pieces in the feed material, the coefficient of material friction on the roll working surface, the circumferential speed of roll ledges are taken as initial data. Such parameters of the crusher, as the size of the gap between ledges of the opposite rolls, the nominal diameter of the rolls, the pitch of the roll ledges in the axial direction, the radii of rounding of the ledges and the hollows file of the roll profile, the angle of sharpening of the rolls, the angle of inclination of the taper sections, the height of the profile, the length of the roll working part, the rotational speed of the rolls, the theoretical output of the crusher are determined on the basis of the authors’ previous studies. Also, the model example of calculation of crusher parameters for processing of granite fraction of size less than 70 and more than 40mm, having 30% yield of lamellar pieces, is given. The following conclusions were made. Firstly, the technique for calculating the parameters of crusher with wave profiled rolls for processing the narrow-sized crushed stone fractions in order to reduce the content of lamellar pieces makes it possible to determine the expediency of complete or partial shape improvement of the pieces of narrow-sized crushed stone fractions. Secondly, it sets the main characteristics of the crusher working member and its drive. Thirdly, it is recommended for calculating the parameters of operational part of the crushers with wave profiled rolls, designed to improve the shape of pieces of narrow-sized fractions of construction crushed stone from hard rocks, which are used as filler in responsible concrete and asphalt-concrete products.