The 64-metre long tunnel boring machine has started to cut through rock about 600 metres below the surface.
The machine is the first of three new underground excavation systems being developed by Rio Tinto as part of its Mine of the Future™ programme to improve the construction and operation of underground mines.
The German-built TBS has been designed and developed by Rio Tinto in partnership with Aker Wirth over the past four years.
The TBS was officially launched today at an underground ceremony attended by Preston Chiaro, Rio Tinto group executive Technology and Innovation, and John McGagh, Rio Tinto head of Innovation.
John McGagh said “This investment offers the possibility for a significant improvement over conventional drill and blast practices. Depending on rock and operating conditions, this system should provide the capability to excavate at more than double the rate of conventional methods.”
Northparkes Mines managing director Stefanie Loader said “This is a very exciting opportunity for our business. Northparkes is renowned for its ability to trial new technology in a real world environment.
“Importantly for Rio Tinto, it provides an opportunity to introduce fundamentally safer processes into the underground mining industry. Safety is a value and is integral to everything we do. This technology will not just help to make our operations more efficient, they’ll also be safer.”
The trial phase at Northparkes will run until about July this year.
Northparkes Mines tunnel boring manager Rob Cunningham said “The next steps following the completion of the trial will be a comprehensive critique of the performance of the tunnel boring system.”
The TBS is controlled on-board by a team of 12 people operating all functions of the TBS and is supported by three underground haul trucks. The on-board team also receive logistical support from an above ground crew of around 15 additional people.
Background
The Tunnel Boring System (TBS) arrived at Northparkes in October last year and took four months to assemble. The machine is 64 metres long with a maximum boring diameter of six metres. After the trial this technology is destined for use in other Rio Tinto underground mining operations internationally.
For a typical deep copper ore body, the rate of horizontal tunnelling could be as high as 10 to 12 metres a day using this new system compared with five to six metres per day that is currently excavated using conventional tunnelling methods.
The TBS incorporates continuous mechanical rock excavation that will not damage new tunnel walls, while still providing the ability to mechanically install ground support in parallel with tunnel advance.
The expected distance of the trial at Northparkes Mines is 1,400 metres.
The TBS is part of Rio Tinto’s Mine of the Future™ programme which aims to enable Rio
Tinto to more effectively carry out exploration; more efficiently access resources and allow safer, faster and deeper underground mining operations whilst economically recovering valuable mineral resources from increasingly difficult deposits