Energy efficiency of a cone crusher with stops

Abstract

Metallurgical, construction and mining industries are based on the process of grinding various materials. The main method of primary preparation of raw materials is crushing of the extracted ore. Up to 4 % of the world’s electricity production is spent annually on crushing rocks to obtain the necessary fraction of material, and for a single mine, the share of energy consumption for crushing can reach 50 % of the annual volume. In addition to spending electricity directly on rocks destruction, some of it is spent on creating a power reserve for a crushing machine (hereinafter referred to as a crusher) due to the fact that currently there is no single method of theoretical calculation of the power of its electric drive, no single method of determining energy costs for rocks destruction. It is known that raw materials extracted from different deposits have different physical and mechanical properties, which has a significant impact on the grinding process. However, difference in power of electric drive of crushing machines is due to the difference in their standard sizes, and the geography of their application is taken into account by the creation of the above-mentioned power reserve. The above factors have a negative impact on the operating costs of metallurgical industry enterprises. The article discusses some designs of crushers in which the destruction of the crushed piece occurs as a result of complex stress state. New design of a cone crusher with stops is proposed, which allows reducing energy costs for crushing materials. Due to the presence of stops and simple kinematics of the working body movement, reduction in the power necessary for the destruction of pieces of brittle materials, regardless of their properties, is achieved. At the same time, in crushed pieces destroyed in a cone crusher with stops, it is possible to create a shear stress state, in which theoretically a reduction in power required for crushing brittle materials is achieved by 2 times in comparison with compression crushers. The conditions of occurrence of shear stress state in crushed pieces during their crushing in a cone crusher with stops are described. The authors give recommendations for the reconstruction of these conditions.