A nine-strong fleet of Epiroc drill rigs is creating increased productivity and both financial and environmental savings for a Tier 1 contractor at a Western Australian gold mine. Damian Christie reports.
Macmahon provides contract services for mining operations throughout Australia and internationally.
One of the contractor’s current engagements is at Mount Morgans gold mine, in Laverton, in Western Australia’s Goldfields region.
Dacian Gold awarded a $250 million open pit mining contract to Macmahon in November 2017 for a five-year period at the mine, where it is undertaking drill and blast, load and haul, and technical duties.
In that five-year period, the mine contractor expects to move more than 100 million tonnes of material, with the option to extend the contract beyond November 2022.
At the start of the contract, Macmahon purchased the first machines in what is now an integrated, nine-strong drill rig fleet. Its preferred choice has been the currently semi-automated Epiroc SmartROC T45 tophammer rig, which has been developed for high performance in harsh applications.
An intuitive control system offers mines and quarries precise drilling and consistent operation, leading to improved blasting results. The rig is also designed to be fuel-efficient, only expending the amount of energy the work demands.
“We have an entire fleet of T45s, the standardisation of the fleet helps reduce our training and maintenance costs,” Macmahon’s project manager Paul Haynes told Quarry. “The platform is well suited with the wide tracks, allowing it to be quite manoeuvrable on uneven terrain.”
Haynes and the onsite team manage the open pit operation at Mount Morgans, which includes drill and blast, load and haul, maintenance, mine planning, and run of mine delivery.
He said the T45 rig is well suited to the local environment, providing “good flexibility in terms of hole sizes. We predominantly drill 115mm holes but due to collar piping and presplits we are also required to use 102mm and 140mm bits. The long mast allows us to single pass the 5m benches which saves a lot of time and enables operators to ‘beat the water’, reducing redrills and collar piping requirements leading to an increase in the productivity of the fleet.”
AUTOMATED ROD HANDLING INNOVATION
The T45 features an automatic feed alignment that enables the operator to maintain the desired angle when drilling, fundamental to the operator’s optimal blasting requirements. In particular, the rig’s automatic rod adding system enables the operator to supplement rods to the exact desired drilling depth.
Kris Thomas, who is the capital equipment product manager for surface and exploration drilling at Epiroc, explains the SmartROC T45s used by Macmahon feature a long feed boom, which is “capable of carrying six-metre drill rods, so there’s higher ability to do a deeper, single plan instead of the conventional 3.6 metres rod which other competitors use”.
The automatic rod handling system, coupled with the 6mm rod capability, enables the T45 to drill the required depths with less rod changes and, according to Thomas, eliminates the need for a single rod change at 12 metres.
“On a conventional rig, you’d have to use three rods,” he said. “With our machine, you can use two rods, so one less rod change per hole over a shift, over a month, over a year is a massive saving in time over that process.”
The other innovation on the SmartROC T45 is the exclusive Powerbit T-WiZ 60 thread for bench drilling.
“There’s two different rod sizes that you can use on the drill,” Thomas explains. “The T51 is a conventional drill rod size, it’s 51mm. The T-WiZ 60 is an Epiroc-designed 60mm pipe and smartly designed thread where it’s much easier for the operator to break out the drill string when he needs to put the rods away, compared to the conventional T51 that can be harder to break out.
“With the T-WiZ 60, your holes will be straighter because there’s more mass to the rod, it’s stiffer, so you’re increasing your ability to get straighter holes.
“As the T-WiZ 60 breaks out so quickly, there’s also less potential for damaging rods,” Thomas adds. “When the conventional rods are stuck there is a lot more hammering of the machine to try to break the rods and you can cause more damage than with prolonged percussion.
“The T-Wiz 60 has 9mm more mass to the rod than the T51, so it’s going to be stiffer or harder to bend, and because of the increased annulus (ie the difference between the 127mm and the T51 bits), your flushing ability is improved. When you’re drilling, you’re flushing air down the hole to push the cuttings up to the surface. With the increased annulus, the cuttings come up more easily.”
For fuel efficiency and high productivity, the SmartROC T45 has been designed to use the least energy. The 242kW Caterpillar turbo-charged diesel engine (Cat C9, Tier 3 and Tier 4), 12 bar Epiroc C146-07 screw-type compressor and standard automatic radiator fan are programmed to automatically adjust to changes in the operating mode. For example, if the rig is tramming or idle, the compressor puts no load on the engine and reduces engine speed.
According to Epiroc, the 1900 rpm hydraulic system does not use or require as much oil as other rigs, and the hydraulic tank is therefore a third of the standard size for its type. Biological oil can also be used at exactly the same cost as regular oil.
“The total cost of ownership of the machine is very low,” Thomas said. “There’s very small amounts of oil required on the drill, so with less oil, there’s less fuel burn, there’s less wear and tear on the machine, and longer component life.
“Obviously with the lower fuel burn, the engine life is greatly improved. The oil capacity is 100 litres in the hydraulic tank – whereas other manufacturers are using 300 to 400 litres in comparison. So you have that hydrocarbon disposal benefit too – you’re not dispensing so much waste oil, which makes it environmentally friendlier.”
OBSERVING THREE CORE VALUES
For Macmahon’s Paul Haynes, the T45s’ innovative features have been beneficial – but to him the diversity and experience of the Epiroc team is the key. “Epiroc’s drills and drilling products come with a whole range of people who have different skillsets that come from different backgrounds,” Haynes said. “It’s great to have these people come out and work with our drillers and other team members.”
Epiroc business line manager Beau Tembey said collaboration, innovation and commitment are Epiroc’s three core values and reflected in the company’s work.
“We all have our strengths and capabilities, within Epiroc and with our customers like Macmahon, and we definitely get the best outcomes when we come together,” he said.
“With innovation, there’s always more efficient ways of working. Whether it’s the technology or materials side of things, improvements can be made. Again, that falls into the collaboration side, and coming up with new ideas and requirements helps us improve and innovate more quickly.
“And commitment, for me, is quite simple. That’s about being accountable and delivering quite simply, from our side. That’s a strong focus of ours – we want our customers to know we’re as committed to providing actual benefits to them as selling a product.”
Tembey believes that Epiroc can play a major role in the automation side of the T45 and other drill rigs going forward.
“Automation is a huge focus, even for us in the drilling tools side, it’s about integration with systems on the drills,” Tembey said.
“It’s important that you’re getting input from the products and the consumables to the drill to advise on the product wear. It’s about integrating the tooling digitally with the tool itself, which will have benefits.”
Tembey added that it is also about having the right data, which is irrelevant “if it’s not translated into beneficial information that has meaning and context and gives you input. Getting more digital at the best level means all those inputs can be realised in one system, and really provide that information and feedback in near real time.”
That is the direction Macmahon is clearly driving towards as it enters the fourth year of its contract at Mount Morgans.
“We’re now transitioning into a period where we are able to look at more of the data that’s captured within our SmartROC rigs and that is exciting,” Haynes said.
“There’s a lot of data we can capture from the drills. I would say we use a limited amount of the available data at the moment and I would believe that we are not the only ones, it’s now a question of how we integrate data analysis into daily routine and convert it into productive operation.”
With more automation and software features, hole and inclination systems, and hole navigation systems available, it is more than likely the SmartROC T45 fleet at Mount Morgans will continue to go from strength to strength.