A haul truck rumbles into the truck shop at the Goldstrike mine on a clear September day. The Nevada sky accentuates the size of the vehicle, a Komatsu 930. It’s a colossus that fills up virtually every inch of the 27-by-27 foot entrance to the maintenance bay. The truck, which can carry loads of up to 310 tons, is here for minor repairs and a preventative maintenance inspection, the latter of which begins with a shakedown.
No, it’s not what it sounds like—or perhaps it is. With the truck idling on chock blocks, the driver aggressively rotates the steering wheel back and forth, causing the truck to shake and roar like a bull in a rodeo. As the truck writhes, mechanics walk around and under the 230-ton vehicle, looking for fluid leaks or worn components.
Some of Goldstrike’s Komatsu 930s have more than 100,000 hours of run time—the most in the world, and a testament to the mine’s maintenance team.
Until recently, haul trucks visited the truck shop every 14 days for scheduled maintenance. Inspections and oil changes took place on the first 14-day rotation, while repairs were carried out on the second 14-day rotation. Each visit took about four-to-five hours. With 23 haul trucks operating at Goldstrike, this meant the trucks were out of operation for about 184 to 230 hours a month.
Earlier this year, Goldstrike launched an optimization program to improve productivity and drive down operating costs. One of the changes that the mine implemented was to extend the period between truck-shop visits from 14 days to 28 days. Instead of bringing the truck to the shop for inspections every fourth week, inspections are now conducted in the field, says Ray Burns, General Supervisor, Mine Maintenance, Planning and Reliability. Any repair work identified during the field inspection is conducted when the truck is in the shop at the 28-day mark. Oil is also changed at that time and a routine preventative maintenance inspection is conducted.
“We’ve compressed things together,” says Burns, who has worked at Goldstrike for 27 years. “We can get repairs and oil changes done in that four-or-five hour timeframe. And doing inspections in the field means we’re being more efficient and saving operating time for the trucks.”
Goldstrike is Barrick’s oldest operating mine, with more than 30 years of production. The mine still has a long life ahead, but as it matures it moves less tons of ore on an annual basis than it once did. This fact, coupled with new efficiency measures, has allowed the mine to reduce the size of its haul truck fleet from 29 to 23 without lowering production levels.
Some of Goldstrike’s Komatsu 930s have more than 100,000 hours of run time—the most in the world, and a testament to the mine’s maintenance team. As the operation has reduced its fleet, it has decommissioned some of these older trucks, yet they continue to serve Goldstrike well. That’s because many of the parts from these vehicles are being salvaged and reused in the existing fleet.
“When we shut these trucks down, some of their parts still have life,” says Julius Stieger, Open Pit Manager at Goldstrike. “So we’ll strip the truck all the way down, take the components, set them aside and, when a truck that is still operating needs a part, we can use these parts.”
Using salvaged parts such as wheel motors, engines, hoist cylinders, front suspensions and tires has saved Goldstrike about $2 million this year alone, Burns says. A new wheel motor, he says, can cost anywhere from $200,000 to $300,000, while a new engine can run $400,000.
Stieger says the mine expects to continue operating with 23 haul trucks for the foreseeable future. As a result, some of the mine’s oldest Komatsu trucks that are still in operation will likely hit run times of 150,000 hours. “We have a lot of history maintaining these trucks, and a lot of our peers come to us to ask how we do things,” Stieger says. “That’s a nice thing and we try to help, but we also let them know that we’re still learning. We’re learning new things every day.”