Abstract: A rotation indication device for a rock bolt including a central rod with a threaded trailing portion. The rotation indication device includes a blind nut having a threaded central recess for engaging the threaded trailing portion and a visual indication means provided at a bottom portion of the central recess and configured such that upon movement of the threaded trailing portion of the central rod into the bottom portion of the central recess, the central rod forces at least a portion of the visual indication means to move through a passage in the blind nut between the bottom portion of the central recess and the outside of the blind nut.

Abstract: A sensor assembly for a rock bolt, wherein the rock bolt includes a central rod, a split tube and a wedge anchor assembly fitted around the central rod, a rock plate, and a nut for attachment to an outer end of the central rod. The sensor assembly includes a distance sensor, a bracket for attaching the distance sensor to an outer portion of the split tube, an elongate spacing member configured to be fitted around the split tube between the nut and the rock plate to keep the nut and the rock plate spaced apart. The spacing member has an opening extending along at least a portion of the length thereof, the opening being sized large enough to allow movement of the bracket along a portion of the length of the spacing member with the distance sensor attached to the outer portion of the split tube by the bracket.

Abstract: A drill string for rotary drilling of underground mining machines includes a first elongate drill string member and a second elongate drill string member. The first member has a main section and a male end, and the second member has a main section and a female end. The male and female ends each have respective threads to provide a thread coupling between the male and female ends, the thread coupling enabling the male end to be secured inside the female end such that the male and female ends overlap axially. A thread lead of the respective threads of the male and the female ends are greater than a diameter of the male end and the female end.

Abstract: A closure system for a trough comprising a first closure member and a second closure member, the first closure member being movable between a closed position, where it closes against the perimeter of a first opening in the bottom of a trough and an open position where it retracts to a position away from contact with the perimeter of the first opening, the second closure member being movable between a closed position where it closes against the perimeter of a second opening in an opposite side of the bottom of the trough and an open position where it retracts to a position away from contact with the perimeter of the second opening, and first and second controllers operable to move the first closure member and second closure member respectively between the open and closed positions.