METHOD FOR OPENCAST MINING OF HORIZONTAL AND GENTLY SLOPING MINERAL BEDS Russian patent published in 1995 - IPC

FIELD: mineral opencast mining. SUBSTANCE: method for opencast mining of horizontal and gently sloping mineral beds includes extraction of useful mineral by subbenches with working them by outward and retreat stopes from top down and its loading into transportation facilities. Distinctive feature of the method: first, route is determined of the combine with cutting member from subbench edge. From the latter, first step is worked in direction towards future final flank with height equalling the thickness of cut layer amounting to 10-60 cm. Then, using the same procedure, the second, third and fourth steps are worked. Rocks in caving block are worked by excavator provided with hydraulic hammer. Then, next four steps of the second subbench is worked using the same procedure, and then, steps of the third and fourth subbenches, up to the full working of opencast. Width of step is taken equal to 12-15 cm. EFFECT: higher efficiency. 3 dwg