Bolted joint for mine support - has cross angles secured each side of trough shaped member by hook bolts and cleats

摘要

The mine support framework using trough-shaped carrier members (1) has two angles (5, 6) connected to it at right angles by a bridging angle (4). The ends of the two angles are curved to match the curved sides (3) of the trough, and the horizontal flanges (15) of the two angles. The bridging angle is supported by a hook bolt (19) each end, each of which hangs over the beaded edge (23) of the trough (1) and passes through the top angle (5 or 6), the bottom angle (4) and a cleat (9 or 10) underneath. These latter three members are clamped together by an upper nut (24) and a lower nut (21) on the threaded end of the hook bolt.