Rebuild masterstroke pays off for miners

A masterstroke by Cummins engineers in Australia and the US has resulted in major cost reduction and environmental benefits for mining companies electing to rebuild their QSK60 engines under a special upgrade program.

The engineers focused on rebuild possibilities for the early generation QSK60, and how it could be upgraded to the latest diesel technology at overhaul time with no major change to the base 60-litre V16 design – a feat that eluded other engine manufacturers.

The key technology upgrade is to fuel injection, with the early unit injection system (HPI) replaced with the high-pressure modular common rail system (MCRS) that is now featured on all of Cummins’ latest generation high horsepower engines.

The 300th upgraded engine, rated at 2700 hp, recently rolled off the production line at the Cummins Master Rebuild Centre in Brisbane, highlighting yet another successful step in the evolution of the QSK60 and why it is the foremost high-horsepower diesel engine globally in mobile mining equipment.

“Reduced fuel consumption and longer life-to-overhaul are keys to lower total cost of ownership, and they were the initial aims behind the engineering of the upgrade program for the QSK60,” says Greg Field, mining business development manager for Cummins Asia Pacific.

“Innovation is at the core of Cummins’ long history, and it has certainly played its part in the QSK60 rebuild options we can offer our mining customers.”

The bottom line is impressive: Diesel particulate emissions are slashed by up to 63% through in-cylinder combustion technology with no aftertreatment. There’s also a plus for maintenance with less soot loading in the oil.

Fuel savings up to 5% are consistently reported in the field for significant greenhouse gas emissions reduction, while life-to-overhaul is extended by 10%, translating to fuel consumption of more than 4.0 million liters before rebuild is required.

Apart from the fuel system upgrade to MCRS, the QSK60 with single-stage turbocharging also features other Cummins innovations in combustion technology that were engineered for Tier 4 Final and Stage V emissions compliance, the most stringent off-highway emission standards in the world.

The rebuild upgrade package can be applied to the two variants of the QSK60 – one with single-stage turbocharging (known as ‘Advantage’) which can be rated from 1785 to 2700 hp, the other with two-stage turbocharging which can be rated at 2700, 2850 or 3000 hp.

The 300th upgraded QSK60 went to Boggabri Coal in the NSW Gunnedah Basin for installation in a Komatsu 930E haul truck. The engine has proved its worth in both coal and iron ore mining in Australia.