IMPROVING THE SCREENING SURFACE AND THE EFFICIENCY OF THE SPLIT ROCK MASS OF STATIONARY SCREENS

The relevance of the work is conditioned by the need of the construction industry in better preparation of raw materials, and to improve the equipment efficiency. The problem faced by enterprises is the division of the stale rock mass into fractions. The screens installed are clogged and cease to perform their function. The purpose of the work is to analyze the working process of fixed grate screen and to develop technical proposals to improve the efficiency of the screening of hard rock mass. Research methodology: workflow modeling of stationary bar screen. Results. In technological complexes fixed screens perform operations of preliminary separation of rock mass (often before the primary crushing). With the simplicity of the design, they have a low efficiency of screening, they require an increased area of the sifting surface, have a significant high-altitude dimensions. Operating experience has shown that the sifting surface of grate screens with an open slit is often clogged and requires cleaning. At a distance between the screen 40–50 mm separation of the curved rock mass is particularly difficult. One of the reasons for this is the lack of methods for selecting the parameters of the screen. Practically the main execution of fixed screens is performed in a two-support version with a transverse arrangement of the connection-beams and with a low height of the screens. Sifting surfaces are made linear. Summary. The mathematical model and technique considered in the article allow to determine the basic parameters of fixed screens. An option of improving fixed screens by changing the design of the PP gives it free and forced multi-amplitude oscillations. This will improve the efficiency of the separation of hard rock mass 5–10 %, expand the scope of screens for the separation of clay fractions 40–100 mm. This will also reduce the construction height and installation angle of the screen by 20 %