Cranes keep concentrators productive

Many Australian producers are having trouble keeping up with demand because of reduced exploration and production levels from leaner times.

Those who have had the foresight to make major investments in new production are reaping the benefits of both that investment and the wisdom to put in place comprehensive plant maintenance programs that help safeguard production levels from unscheduled downtime and the widespread skills shortages caused by the worldwide resources boom.

One of Australia’s most successful goldminers, Newcrest, had such foresight. Cadia mine, the largest gold and copper producer in New South Wales and one of Australia’s largest gold producers, producing 300,000 oz/y of gold and more than 25,000 t/y of copper, set in place a crane maintenance agreement with KCI Konecranes to help ensure uninterrupted production . 

The Cadia operations comprise a large low-grade open pit at Cadia Hill and a higher grade underground mine at Ridgeway. The two concentrators are located adjacent to each other and share a number of infrastructure facilities and services. This enables the two to be efficiently operated as a single complex.

To support the concentrators Cadia uses more than a dozen specialized cranes, often simultaneously, to ensure quality maintenance of its production equipment, including heavy plant such as one of the largest SAG mills in the world (20 MW), and two ball mills rated at almost 9,000 kW. This is where KCI Konecranes comes in.

“The extensive infrastructure at Cadia has to be serviced proficiently to tight deadlines during limited scheduled equipment shutdowns,” says Darrin Polglaise, Northern NSW Branch Manager of Konecranes’ operation in Australia.

“In 2004 Cadia and KCI Konecranes jointly reviewed the existing maintenance cost structures.  We then developed a maintenance programme based on the knowledge which we had acquired from our experience on the site over many years since. This was further tuned to the operation requirements by implementing a smarter approach that would considerably reduce the overall cost of their maintenance.

“We initiated a programme that focused on key issues such as proactive actioning of repairs on problem areas of cranes.  We also developed a flexible servicing programme that went beyond preventive maintenance and provided Cadia the comfort of knowing what the costs of repairs and additional works would be, removing any surprises.  Being able to predict equipment expenditures was an offshoot of the ongoing reviews of key equipment, but one that was appreciated by the Cadia operations management.”

This equipment includes specialized cranes ranging from less than 1 t to more than 100 t capacity, which are relied upon heavily in key production areas such as the SAG mill, flotation building, crushers and workshop. “The cranes involved are sophisticated units. Because the technology is quite advanced, it is difficult for mining companies to source these technical skill sets that not only include expert repairs but also engineering expertise and experience on the broad range of equipment employed here.  KCI Konecranes works with Cadia to provide this world-class expertise,” said Polglaise.

 “During a shutdown, Cadia would have between 100-200 contractors working on site and the KCI Konecrane engineers blend in as part of that  team.  This co-operation and teamwork is important because if any of the cranes stopped in the middle of an operation, it could delay the entire shutdown and would result in a major production loss. 

KCI Konecranes Managing Director of Southeast Asia Pacific, Edward Yakos, says that “working with Cadia, and employing our site specific knowledge, we have been able to reduce both the occurrence and the cost of breakdowns overall.  With their key production equipment and gold production at its highest levels, we were restraining their overhead crane maintenance costs to their lowest level in several years.”