In this method of raiseboring, the pilot hole is drilled upwards to a higher level of elevation in the mine or civil project.
Once the desired length has been achieved by the pilot drilling process, the drill string is retrieved, reamer attached and then pushed upwards into the ‘backs’. The cuttings will fall to the lower level by gravity, and are collected in a special collection chute which is attached to the top of the raiseboring machine.