2 d4 TM Mill Drivesystem 7 MW 7 MW 14 MW 28 MW 7 MW 4 MW 7 MW 7 MW 7 MW 4 MW 7 MW 7 MW SAG mill 32 ft. single drive The natural progression in gear/pinion mill drives: The QdX4TM Mill Drive provides the next step in the evolution of change in mill drive architecture, while allowing the system to be built with components that are within current manufacturing capabilities.