Mechanical and physical aspects of the theory of interaction between a crusher hammer and an air-grain layer

Abstract

When crushing various raw materials of mineral, vegetable and animal origin hammer crushers of various designs are widely used, in which the rotor with hammers attached to it can be located both horizontally and vertically. During the operation of a hammer crusher with a vertical axis, a stable air-grain layer is formed near its deck, upon contact with which the crusher hammers wear out, and the wear itself depends on the contact stresses acting in the layer and the path (stay time) of the hammers in it. The problem posed is similar to the well-known problem of applied physics about a rotating disk, with the difference that tensile stresses act on the disk, and compressive stresses act on the air-grain one. The article obtained a theoretical expression for the linear wear of the crusher hammer, which depends on the characteristics of the layer, the properties of the crushed material and the grinding time, and in a complex way - from the distance from the edge of the hammer to the axis of its suspension. A comparison of the theoretical wear curves with the real outlines of worn hammers shows their identity.