Master Drilling CEO, Danie Pretorius, talks about his company’s recent success in completing the world’s deepest raised-bore shaft construction project.
On April 26, 2022, Master Drilling hosted an event at Northam Platinum’s Zondereinde mine to celebrate the final breakthrough of the new 4.8 m diameter, 1 380 m mine shaft – the world’s deepest raised-bore shaft construction project ever completed.
Danie Pretorius, Master Drilling CEO and a mechanical engineer, started this business in 1986 with a key focus on raise boring of mine shafts and related services. The first of Master Drilling’s self-designed raised bore drilling rigs came into operation in South Africa in 1988 and its first world record was established in 2012 with the 1.07 km pilot hole at Lonmin for a 5.5 m ventilation shaft; and today, with over 140 raise boring rigs operating in over 23 countries across the world, Master Drilling is considered to be the world leader in this technology.
At 1 380 m deep, Shaft 3 at Zondereinde, a PGM mine in Northam in the Limpopo Province of South Africa, has now set a new world record for the longest and most directionally accurate raise bore shaft ever drilled. “Never before in the history of the world has a 1 380 vertical shaft been raised bored. So that was something significant for us at Master Drilling,” says Danie Pretorius.
Key to this success is the accuracy achieved, which is all down to the pilot hole that deviated by less than 140 mm from a true vertical line across its entire depth, a miniscule amount. Completed back in July 2020, this first stage of the project set its own world record for raised bore pilot drilling.
“Another key Zondereinde success was the timing. We finished the project within budget and within the planned timeframe, which is a remarkable achievement for such a lengthy project. This should be ticking a lot of boxes for future miners all over the world seeking to explore and access new ore bodies or to economically establish ventilation shafts,” he adds.
In terms of costs, Pretorius points out that a shaft of that size and depth would take the best part of five to seven years to construct using conventional shaft sinking, drill and blast methods. Using the raised bore technique, the time was slashed to just two years seven months (31 months), costing less than 15% of that estimated for shaft sinking using drill and blast construction methods.
“With respect to safety, time, and costs, this was a remarkable achievement, and we are sure that a number of mining houses will be looking at this closely before making decisions about new large diameter, extra-long raised bore mine shafts,” he notes.
Pretorius also points out that Master Drilling continues to seek ways of keeping abreast of modern innovations. “We have also recently invested in two companies in the digital space: AVA Solutions and the A&R Group. These companies have nothing to do with what we have been doing for the past 30 or years, but we thought we needed to align ourselves to today’s digital world to support where the mining industry is going with respect to big data and AI,” he says.
A&R Group specialises in intelligent digital safety devices and management systems such as tracking and proximity systems for underground rail and trackless equipment, while AVA Solutions (AVA) is a specialist in data-driven mining fleet management solutions. AVA’s low-cost Software as a Service (SaaS) platform is currently being used to analyse and track load and haul vehicles across 28 different sites in five countries.
“Safety is the critical aspect of underground mining success and the use of software, AI and big data for proximity detection, condition monitoring and production efficiency are fast becoming key aspects to improving this industry.
Pretorius concludes: “Using state-of-the-art solutions such as these, we at Master Drilling are proudly supporting our clients’ unique needs with in-house designed and manufactured equipment, which we support with ever advancing training, tracking and maintenance capabilities.”