NON-EXPLOSIVE METHOD FOR SEPARATION OF LARGE-SIZE GRANITE BLOCKS FROM AN ARRAY Russian patent published in 2019 - IPC E21C37/02 

FIELD: mining.

SUBSTANCE: invention relates to mining – to blast-free methods of separation of blocks from massif of high-strength rocks of natural stone and is intended for separation of large-size granite blocks from massif. Explosion-free method of separation of large-size granite blocks from an array includes drilling in a vertical back plane at a distance of width B of the unit and parallel to a frontal plane of a ledge of a line of boreholes with diameter d, arranged with a pitch A<(5–12)·d, and depth equal to unit height H, working boreholes selection from boreholes line for wedge devices accommodation in them, wherein arrangement of working boreholes from each other is determined proceeding from the area of initial crack formed from one wedge device hammered into working borehole, arrangement of wedge devices in boreholes, impact introduction of wedge devices into working boreholes with formation of main crack in vertical rear plane, separation of end blocks. Lines of boreholes with diameter d with the specified pitch A and depth are drilled and in vertical end planes perpendicular to frontal plane of ledge and formation crack. Distance between vertical end planes of end blocks is equal to length L of end block. Working boreholes are selected from the line of boreholes in vertical end planes for arrangement of wedge devices in them. Arrangement of these working boreholes from each other is determined proceeding from the area of the initial crack formed from one wedge device hammered into the working bore. Wing devices are used, in which annular ledge on wedge device working part is made in the form of truncated cone, said wedge devices are placed in these working boreholes and their impact introduction is performed, at that, the wedge devices are first introduced into vertical boreholes in order to form a main crack therein, and then impact insertion of wedge devices arranged in working boreholes of vertical end planes is performed, forming transverse cracks in vertical end planes for separation of end blocks.

EFFECT: increased efficiency of explosive-free production of large-size granite blocks by excluding labor-intensive operations of formation of vertical end slits by thermal cutting of stone, as in prototype, as well as by increasing the level of breaking forces acting on walls of working boreholes from wedge devices capable of separating high-strength granite blocks from the massif, while reducing power consumption.

1 cl, 4 dwg