Beyond-expectation drill consumables life increase with service contract at Lumwana

lmc.jpgA service contract originally signed in 2009 between Sandvik Mining Zambia, and Barrick’s Lumwana copper mine in that country’s North-West province, has created a beyond-expectation success story, with exceptional improvements in the life of the rock tools used in the pit.  Lyford Banda, Sandvik Mining rock tools manager for Central Africa, says his team was committed to improving what was historically the “very ordinary” performance of the rock tools.

Paul Sumich, Barrick’s drill and blast co-ordinator at Lumwana, explains: “It was clear that we needed to try and lift the average lifespan of all rock tools to drive down our cost per metre. Up to this point, we had no established history on all DTH consumable life span. This required us to establish a formalised system, other than depending on estimations on bit and other consumable life span. The service contract with Sandvik Mining allowed us to tackle this as a team effort. ”

The combined efforts of Lumwana and Sandvik Mining created a more in-depth reporting system. The new system caters for all the short falls that were previously encountered, including identifying gaps in the operators’ drilling techniques, reporting systems, handling of tools failures and localised tools usage.

“This has created a greater awareness among everyone involved and we try to work out the problems together and stop these issues recurring,” Sumich says. “We needed our operators to start taking ownership of the rock tools they were using and we found that the best way to approach this was to effectively allocate each rock tool to a drill rig.

“Clear and effective communication played a pivotal role in the success of the system. Lifespan targets for the rock tools are communicated to all the operators, and reports of the tools’ performance are communicated to all stakeholders. As a result, the operators have started taking responsibility for the use of
consumables and our bit life has begun increasing slowly, but surely.”

Sumich points out that one of the main guidelines put in place was to localise drill bits to certain working areas in the pit at certain times in the drill bit’s life, to tap the full performance potential of the bit. For example, there are specific bits for hard areas and bits for soft areas. With the pit currently at 6 km long, operators are able to apply this approach quite easily with a resulting immediate increase in bit life.

“We also made a point of emphasising the monetary value of the consumable with the operators,” he continues. “This was also done in conjunction with the premature failure reports. These discussions made the operators more aware of what they needed to do to achieve the best possible life span out of these consumables.

“On the maintenance team, there is huge focus on timely and efficient ways of transporting, servicing and delivery of consumables so that there is continuity in the servicing of the rock tools. Modifications were made throughout the entire process to ensure that delivery of consumables and availability of backup services such as spare bit sharpening machines was optimised.

“With the hammers, certain components are more frequently changed to protect the hammer failing quickly, because we have very abrasive ground here at Lumwana, and this proved successful in increasing our hammer life. As an added measure, we conducted an audit on all the hammer oilers on the drills to make sure the hammers were getting the minimum required amount of oil and that it was the right oil for the job.”

The Sandvik Mining team also arranged a highly successful consumables training and information day for all the operators and Sumich says this has helped in no small measure to increase the consumable life span. This kind of training will be ongoing, conducting one or two sessions each year

Banda adds: “We’re really proud of the pivotal role the Sandvik Mining team played in shifting the operators’ approach to the use of rock tools. Six months after the introduction of the new controls, on average, bit life improved by 33% and hammer life by 11%. During the course of this year the mine reduced its bit size to a slightly smaller size, with no loss on performance. The success of the service agreement has led to our contract being renewed

“Lumwana and Sandvik Mining work closely together to harmonise supply of rock tools. Forecasting is done by both parties to make sure the right tools and quantities are stocked by Sandvik Mining and supplied as and when required. This has worked very successfully so much that the mine is guaranteed of stock availability all the time.

In summary, it shows that by working together, we can enjoy huge benefits which in this case include:

  • Improved tools life resulting in lower cost per metre
  • Improved drifter life
  • Clear and effective communication that improves motivation of operators and service personnel
  • Availability of stock.