Abstract: A mine tunnel support system of the type comprising spaced interconnected support sections is described. The support system is advanced along the tunnel in the forward direction in which mining is proceeding. Bolting machines may be carried on the support sections. A drill may be provided on one section and a bolt inserter provided on a section rearwardly thereof. As the system is advanced, the bolt inserter can insert a bolt into a hole previously formed by the drill. The operation of providing roof bolts is therefore split into a number of stages. A mechanism for erecting and/or pre-stressing permanent arch supports may be provided at the rear of the sections.

Abstract: An improved bending machine with three rollers which may be driven at different speeds and/or with differing torques. A control system receives signals indicative of the position and speed of rotation of one or more of the rollers. The control system is connected to a mechanism for adjusting the position, rotational speed and torque of at least one roller so that commands can be given to vary these parameters. Thus, the machine can be readily and accurately adjusted to produce bends of differing dimension in a strip workpiece.

Abstract: The invention relates to arches for use in tunnels such as underground mine tunnels. These arches are composed of a bent metal beam often of "H" or "T"-section. Problems have previously arisen in accurately bending the beams to the required shape. The apparatus of the invention includes a D-shaped former which is rotatable relative to a roller. The beam is clamped to one end of the former and on rotation of the former relative to the roller, the beam is bent around the former so that it assumes the required shape, the ends of the beam being clamped to the former. A cutting device may be employed to cut the beam, while bent around the former, into three or more sections.