Mechanical Technology January 2016

⎪ Power transmission, bearings, bushes and seals ⎪

New mill drive system for improved efficiencies Metso’s latest innovation, the Metso QdX4 Mill Drive system is mooted to help customers achieve high efficiencies in mining operations.

O ver the past three years, Metso has worked in close collaboration with CMD and Ferry Capitain to develop a new high-powered mill drive solution for large SAG and ball mills in the mining industry. After exhaustive design research that concluded with build, installation and continuous full-scale testing op- erations, Metso has now introduced its QdX4 Mill Drive. This system was tested for over three million cycles at 28 MW (2×14 MW) with an input speed of 320 rpm, proving the torque splitting system arrangement. In the past, grinding mills operating be- tween 18 and 28 MW required a large electrical wrap-around motor, known as a gearless mill drive (GMD). The Metso QdX4 Mill Drive system is an alternative option to the GMD. Until now, the gear- driven solution for large SAG and ball mills was limited to 18 MW. Responding to the needs of industry “Traditionally, the mining industry has been somewhat reluctant to change, but change has oc-

was to design a robust, reliable, cost- effective, high-powered mechanical solution without compromising the high design standards we are all used to seeing in our customers’ specifications,” says Frank Tozlu, product manager of large grinding mills at Metso Minerals’ grinding headquarters, in York, Pennsylvania. “SAG and ball mill specifications have been developed over many decades and we are still developing them today. We must continue to look at advancing innovative ideas through our standards and practices when expanding upon trans- mittable mechanical power,” he adds. The Metso QdX4 Mill Drive system provides the next step in the evolution of mechanical mill drive architecture. The progression from a single- to a dual- pinion arrangement has been a way to transmit twice as much power in the Taking architecture to the next level

Metso’s QdX4 Mill Drive system rearranges the dual pinion arrangement into a quad system that equally divides input power from two load-sharing motors into four pinions. a quad system that equally divides input power from two load-sharing motors into four pinions,” Tozlu explains. With this architecture, the Metso QdX4 is capable of delivering up to 32 MW to horizontal mill comminution systems. The QdX4 Mill Drive has many fea- tures that help customers achieve both time and cost efficiencies from an equipment point of view and in terms of the overall costs of a large-scale operation. For example, two installed QdX4 drive units weigh less than one GMD quarter section. This significantly reduces transportation cost, de- livery time, equipment handling and site preparation. The system also reduces the need for massive reinforced foundation volumes and the requirement for customers to install large crane capacities. Similarly, there is no need for ex- Driving time and cost efficiencies

past. “We have sim- ply rearranged the dual system into

curred nonetheless and the industry is now encour- aging innovations to operate in a more efficient way. Our goal

Metso’s new mill drive uses traditional engi- neering load distribution calculations for sizing standard base-plates and hold-down anchor

bolts, very similar to that seen with dual-pinion drive arrangements.

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Mechanical Technology — January 2016