MASTER Drilling’s Horizontal Raise Boring (HRB) technology is ready for international roll-out after a successful pilot test at Petra Diamonds’ Cullinan Mine in South Africa. HRB can replace conventional drill-and-blast mining and promises to increase productivity thanks to its continuous process of rock boring, and in addition offers significant safety benefits.
|Master Drilling operates in the mining, underground and open pit business, and has built relationships with some of the world’s biggest mining concerns.|
The new technology will enable more mining construction projects to meet the required hurdle and feasibility rates towards becoming producing mines. Projects with less safe access, such as deeper mining operations and higher stress zones, are also more likely to pass feasibility tests thanks to the safety improvements that HRB brings.
Master Drilling is a South African-based drilling solutions provider with over 160 drills across 17 countries. HRB is a new rock boring solution that can be offered to Master Drilling’s existing client base of multinational miners as well as new clients in mining and civil construction. The technology is expected to offer support to Master Drilling revenue growth over the medium to long term, and thereby provide further income diversification.
“HRB is a locally developed, world-first technology that promises to change the very fundamentals of the global mining industry,” said Master Drilling CEO Danie Pretorius. “The feedback from our multinational business partners from Southern Africa and Latin America on visits to the actual technology has been highly encouraging.”
HRB will provide the mining industry with an excavation and construction tunnelling tool for the mechanical excavation of a tunnel between two existing access points, very similar to the standard form of raise boring. The steady progress of the reamer is able to excavate an average 6 metres per day, compared to 2 metres in conventional drill-and-blast cycles.
The technology offers the much-needed mechanisation to reduce the number of workers who are exposed to dangerous underground conditions.
The benefits extend across the project-chain and include, amongst others:
- No need to use explosives;
- No blast effected damage inflicted to the tunnel sidewalls;
- The structure of the tunnel is stronger due to the circular profile of the tunnel;
- Reduced rock support costs;
- Improved tunnel construction accuracy;
- Lower excavation costs;
- Continuous operations not effected by blast re-entry;
- Greater remote operated possibilities; and
- In certain locations it is impossible to assemble a tunnel boring machine (TBM) due to its length and size. In these locations the plant for raise boring is smaller and easier to transport.
The pilot project at the Cullinan Mine involved boring and excavating a 180 metre horizontal tunnel with 4.5 metre diameter through the kimberlite ore. The construction method entails first drilling a smaller pilot hole through the kimberlite, which was challenging as no water can be used for flushing. The pilot hole also needed to be near perfectly straight. For these reasons Master Drilling pioneered using vacuum air suction and laser assisted directional steering in collaboration with a US-based company, which is typically used in civil construction.
“The HRB technology has the potential to become the new normal for underground diamond mining, if not mining in general, thanks to the benefits it brings in terms of safety, lower costs and a faster advance rate,” said Petra Diamonds’ CEO Johan Dippenaar. “We plan to continue using HRB at the Cullinan mine and are assessing the potential of deploying it at our other sites as well.”
Master Drilling, which was established in 1986 and listed on the JSE in 2012, operates in the mining, underground and open pit business. It has built relationships with some of the biggest mining concerns in the world.
The business model is that of a contractor which designs and manufactures its own drilling equipment to provide complete drilling service solutions, and does not sell any of its machines. Master Drilling recorded revenue of US$58.3 million in the six months ended June 2016 and net profit of US$9.6million for the period and market capitalisation of R2.5 billion, with a US$209 million order book excluding HRB.
Master Drilling has acquired a 40% stake in Swedish raise boring company Bergteamat, which will not only establish the company’s European footprint, but will also allow it to tap into existing technology and operating methods whereby the ratio of man to machine can be reduced from the current accepted norm of 20 to six.
“Master Drilling is about selling a solution and not a product. Our technologies are the result of identifying and responding to needs in the market - ahead of the curve,” said Danie Pretorius.
Over the years Master Drilling has developed new technologies including the Remotely Operated Shaft Inspection Unit (ROSI), amongst others. Currently Master Drilling is developing the Blind Shaft Boring System (BSBS), a mechanised system for boring a vertical shaft to a depth of 2000 metres with finished diameters ranging from 10 metres to 13 metres. No underground access is required for the BSBS to start boring operations as a shaft sinking method.