Leading power and automation technology group ABB has commissioned four low-speed dual-pinion drive systems at the Detour Lake gold mine in Ontario, Canada, according to a company announcement; once fully operational, the open-pit project will be among the biggest in North America.

The systems include the world’s largest low-speed dual pinion mill drives. The low-speed concept operates without a gearbox, said ABB representatives, motors drive the pinions directly, increasing overall system efficiency.

According to ABB, the dual-pinion mill drive systems are the most operationally and mechanically friendly solutions available on the market today. Features include variable-speed operation, real-time frozen charge protection, a frozen charge remover function and controlled roll-back and positioning without additional drive, according to ABB.

Features and drive characteristics enable smooth mill operation, they added, while reducing maintenance requirements in addition to increasing energy efficiency and complete production line availability.

Pre-commissioning began in Q3 2012 with consecutive commissioning of grinding line 1 and 2 completed the next year. The first line has been operational since January, the second since February, and commercial production was reached in mid-August.

ABB’s supply scope included four dual-pinion low-speed mill drive systems for two SAG mills and two ball mills, each consisting of two synchronous motors, converter transformers and ACS6000 frequency converters. These include active rectifier units allowing the mill drives to achieve a power factor of 0.90 leading. ABB, in addition, delivered the programmable logic controller (PLC) to control the drives and mill auxiliaries; each mill drive has a rated power of 15 MW.

The Detour Lake mine, 100%-owned by the Detour Gold Corp., lies 8 km west of the Ontario-Québec border and 180 km northeast of Cochrane. The open-pit mine has proven and probable reserves of 15.6 million gold oz.