For optimal torque delivery as a function of cost, there are critical parameters that need to be
communicated to the gear designer from the mill builder when designing gear drive systems for ore
grinding applications. Apart from loads and speeds, interface dimensions and site specific conditions are
also needed. Deciding up front which gear rating practice to select can affect the torque capacity of the
drive train by ~1 5%. How to deliver the torque to the mill pinion, either by a gear reducer or low speed
motor, influences the distribution of cost between the prime mover and the gear train. This paper will
outline the design considerations that go into construction of the drive system in order to explain why
specific data is required and where design freedom is necessary. A clear specification up front that allows
for matching interface dimensions while allowing for the most cost efficient up front design achieves this
goal.