Features of material movement in a vertical chamber of a vibratory jaw crusher when producing a fine-grained product

Abstract

Currently, vibrating jaw crushers show a fairly high efficiency of the technological process. An extensive amount of research carried out at the Dnipro University of Technology made it possible for the first time to substantiate the possibility of using a vibratory jaw crusher with a vertically located chamber and a pendulum suspension of the jaws as an independent grinding unit for the production of powder materials. The high-frequency impact nature of the load on the material implemented in vibrating jaw crushers made it possible to reduce the energy consumption and metal consumption of the plant, to increase the degree of crushing, which can reach the value i > 100. However, the specifics of the process of interaction of the material with the surface of the jaws in the vertical working chamber and the features of its unloading remain unknown. The refinement of this process was carried out by an experimental method on a laboratory sample of a vibratory jaw crusher ВЩД-130 using high-speed photography. The crusher includes the main elements: a body mounted on elastic elements, crushing jaws, articulated with the body by means of axes. The side surfaces of the crushing chamber are limited by transparent glass walls rigidly connected to the crusher body. The vertical movement of the jaws was determined by the readings of the vernier. The starting material was pieces larger than 40 mm and large bulk material with a grain size of 10…15 mm. An analysis of the nature of the movement of material throughout the crushing chamber showed the need to consider the chamber of a vibratory jaw crusher as two interconnected zones: crushing and grinding. Further studies were carried out for each zone.The productivity of the crushing zone is determined by a known method. It is necessary to create a rational profile of the working surface of the jaws on the basis of additional studies. Studies of the grinding zone made it possible to obtain a physical picture of the interaction of the material with the jaws over the period. In the lowest position, at the initial moment of unloading, the speed of the finished product is practically zero. When determining the productivity of the grinding zone, it is advisable not to take into account the unloading of the material at the initial speed.