Drilling of the pilot hole at number 3 shaft, a new vertical shaft at the Western extension section of Zondereinde, commenced on 25 September 2019 and the receiving chamber underground was reached on 18 July 2020, completing the 1 382m hole, and setting a new world record. The previous record was that of a shaft measuring 1 070m, that was drilled in 2012 at Lonmin’s K4 mine.
Number 3 shaft currently being developed by Master Drilling through raiseboring, is considered to be safer, quicker and more cost effective than traditional blind-sinking. Raiseboring comprises two key phases: the drilling of a pilot hole, followed by reaming of this hole to its ultimate diameter. Critical to the success of raise-boring is the accuracy of pilot drilling and this becomes increasingly challenging the longer the shaft.
Danie Pretorius, CEO of Master Drilling says that the record is impressive as it was achieved using a tool that has never been used for such an application, coupled with a high technology machines. “It clearly highlights the superiority that adaptation and technology bring to drilling solutions, which is something that Master Drilling has been working relentlessly at over the years. As a result, we are able to provide cost effective, safer and accurate drilling solutions for our clients,” says Pretorius.
Master Drilling used ground-breaking oil well directional drilling and combined it with its own designed and manufactured, modern, high technology RD8 machine as well as skilled operators, to achieve the level of accuracy required by directional drilling in order to create a shaft that can be equipped for both man and material hoisting. The RD8 machine monitors a number of operational metrics and takes corrective actions automatically, providing the accuracy required. The water management regime is a fundamental part of this process, as it ensures that quality readings are obtained from the directional tool.