Method and apparatus for drilling holes in soil or rock

摘要

A method for drilling holes in soil or rock, especially for producing prestressed ground anchorage. A hole is drilled by a drill column formed of lengths of pipe with a drill bit driven by a rotary and/or percussive drive. The wall of the borehole is supported by a casing formed of lengths of pipe driven by a rotary and/or percussive drive of a drilling tool. The lengths of pipe of the drill column and the casing are taken from a magazine by machine and transferred back to the magazine after drilling the hole. Each length of pipe for the drill column is taken sequentially from the magazine by the drive of the drilling tool for the drill column and each length of pipe for the casing is taken sequentially from the magazine by the drive of the drilling tool for the casing. Each length of pipe for the drill column and each length of pipe for the casing is returned sequentially to the magazine.