RAMPING UP AT ROY HILL
A fleet of Cummins-powered Hitachi excavators is pivotal to the success of the $10 billion Roy Hill iron ore mining operations in the red expanse of Western Australia’s Pilbara region.
The first iron ore from Roy Hill was shipped in December 2015, and in September 2017 the mine hit a significant milestone, reaching its targeted run rate capacity of 55 million tonnes per annum (Mtpa) for the first time.
A reliable excavator fleet is the backbone of any mining operation and by the end of 2018 a total of 14 Hitachi diggers will be at the Roy Hill ore face.
Roy Hill has a strong legacy at its core. The mining, rail and port operation is majority owned by Gina Rinehart’s Hancock Prospecting, founded by her late father Lang Hancock who is credited with uncovering much of the Pilbara’s vast iron ore riches in the 1950s. The balance is held by Japan’s Marubeni, South Korea’s Posco, and Taiwan’s China Steel Corporation.
Initial mine life is 17 years with a likely extension beyond that of 12 years. Multiple pits are in production at any one time and the mining is carried out by Roy Hill on an owner-operator basis.
"When we have our full complement of 14 excavators we'll be aiming for total material movement of one million tonnes a day," says Wayne Borrett, loading and drilling superintendent at Roy Hill.
At the end of 2017, the Hitachi fleet totaled 10 units with average availability, including downtime for scheduled maintenance, exceeding 90% – performance that earned a nod of approval from Wayne Borrett.
The Hitachi fleet is currently spearheaded by two EX8000-6 backhoe units, with a third EX8000 to be added in 2018. One of the largest hydraulic excavators in the world with its 837-tonne operating weight, the EX8000-6 has dual Cummins QSK60 MCRS engines pumping out close to 4000 hp.
The 60-litre, V16 engines power the EX8000’s hydraulics system – a system of 16 main pumps which move 8000 litres of oil a minute to achieve maximum breakout force. The Roy Hill machines are equipped with 43 cubic metre buckets which scoop up around 80 tonnes of material at a time.
"Our target is to move 6000 tonnes of overburden an hour with an EX8000 and on a good day it will exceed that," says Borrett. He points out the EX8000s will operate close to 7000 hours a year, and their QSK60 MCRS engines will have an 18,000-hour life-to-overhaul based on fuel burn.
The digger fleet also includes four EX5600-6 units, with a fifth to be added in 2018. With an operating weight of 535 tonnes, the EX5600 is powered by dual 50-litre Cummins QSK50 MCRS engines delivering a total 3000 hp. The oldest excavator at Roy Hill is, in fact, an EX5600-6 which went into service in September 2014 and had an engine change-out at 18,092 hours in 2017.
The rest of the excavator fleet includes three 360-tonne EX3600-6 units with single Cummins QSK60 MCRS engines rated at 1945 hp – two more EX3600s will enter service in 2018 – and a 114-tonne EX1200-6 with a Cummins QSK23 rated at 760 hp.
"We've had minimal issues with our Cummins engines," Wayne Borrett points out. All the QSK60 and QSK50 engines incorporate the technology key to lower life cycle costs – Cummins' high-pressure modular common rail fuel system (MCRS). Longer life-to-overhaul, improved reliability, reduced fuel consumption and smoother, quieter operation are among the key elements of the MCRS technology roadmap.
Roy Hill's journey from construction to completion and subsequent ramp up has been nothing short of impressive. After battling a series of red tape obstacles – more than 4000 licences and permits before construction could even start – the race was on to bring the mine to reality. Today, Roy Hill is powering ahead, with sights set high across all facets of the business from production through to community initiatives and advancing technologies and innovations.
Through dust, extreme heat, and high engine load factors the Cummins-powered Hitachi excavator fleet at Roy Hill is fronting up to move one million tonnes of overburden a day.