Master Drilling Group’s annual results presentation provided a few eye-opening updates on the company’s mechanised mine development fronts, with Director, Koos Jordaan, highlighting a potential first deployment of the company’s Shaft Boring System (SBS) at Royal Bafokeng Platinum’s Styldrift mine in South Africa.
A raiseboring specialist that has diversified into other complementary areas over the last decade, Master Drilling has consistently devoted capital towards its technology developments.
During the 2021 annual results presentation, Jordaan confirmed that the company had started tunnelling work on an exploration decline at Anglo American Platinum’s Mogalakwena PGM mine in South Africa, using its Mobile Tunnel Borer (MTB), as well as highlighted the ongoing development of a next-generation design that would cater to the industry need to safely and quickly establish twin declines for mine access.
The MTB is a modular horizontal cutting machine equipped with full-face cutter head with disc cutters adapted from traditional tunnel boring machines. Unlike these traditional machines, it is designed to work both on inclines and declines, with the ability to navigate around corners and construct 5.5-m diameter decline access tunnels.
Having initially been tested in a quarry in Italy in soft rock, it then made the trip back to South Africa to carry out a 1.4 km project at Northam Platinum’s Eland platinum group metals operation in South Africa, in harder rock. This project was terminated in March 2020 due to the COVID-19 pandemic. Last year, however, the company announced it had signed an agreement with Anglo American Platinum to deploy the MTB at Mogalakwena as part of a turnkey contract to sink an exploration decline.
On the development of MTB 2.0, Jordaan said: “We are already working on the second-gen MTB being confident that the concept provides competitive value versus the past as well as other current developments.”
He said the company envisioned future projects using two MTBs simultaneously to establish traditional twin declines for access to underground mines for fast access from “A-to-B” and a quick turnaround to steady-state mining operations.
The company is also carrying out early-stage work with Element Six and the De Beers Group on cut and break technology which, when applied in tandem with the use of the MTB, could enable even more continuous cutting applications.
Element Six, as a company, was established to harness the unique properties of synthetic diamond (polycrystalline diamond or PCD) and tungsten carbide to deliver supermaterials that improve the efficiency, performance and reliability of industrial tools and technology. One of the obvious applications was in hard-rock cutting where OEMs have trialled PCD materials.
Jordaan said the company could leverage cut and break technology with MTBs to create flat floors and breakaways, allowing the circular MTB to continue cutting the face without stoppages.
Looking at vertical developments, Jordaan also provided an update on the SBS.
This machine was initially billed as a blind shaft boring system able to sink 4.5-m diameter shafts in hard-rock down to 1,500 m depth.
Last year, Jordaan said it planned on introducing a “smaller scope system” as part of its introduction to the industry, adding that it had signed a letter of intent with a prospective South Africa project that could see a machine start sinking activities in the first half of 2022.
In the most recent update, he said the letter of intent was with Royal Bafokeng Platinum’s Styldrift mine.
“We are now building the SBS and working towards hopefully converting the letter of intent from RB Platinum to a contract award; we already engaged with them in investigation and readiness work should approval be granted,” he said.
The first SBS being built is a 4.1-m-diameter scope machine with a capability of sinking shafts up to 1,500 m depth, according to Jordaan, who explained that this “smaller shaft scope” was part of a plan to lower the machine’s implementation cost.
“But we are already engaged with opportunities regarding a larger scope of service,” he clarified. “The cost benefit of this method drastically increases as the scope increases versus conventional sinking.”
Aside from the MTB and SBS projects, Jordaan said the company was working on the LP100 development project for its raiseboring division. This is a highly mobile and high-capacity articulated wheel carrier to carry out up and down slots, as well as smaller raiseboring holes, remotely, he explained. At the same time as this the company is looking at developing electric track carriers for its raisebores that, when applied, would come with a much lower carbon footprint.
This came on top of plans for a new box hole boring machine, two new core drilling rigs – one for underground and one for surface – and an experimental rock cutter machine it is working on with African Rainbow Minerals in South Africa.