“You’d get jumper wires going from here to there. With the solid-state system, everything is enclosed and it tells you right on the screen where the failure is. There’s also an impact on safety because you’re not crawling all over the machine when there’s a broken wire or a faulty sensor.”
Electrical systems are vulnerable to failure in underground mines because of corrosion, vibration and other harsh operating conditions.
Sandvik has also standardized its wiring systems to simplify and streamline maintenance.
“It doesn’t matter if it’s a 3-yard loader or a 12-yard loader,” said Maki. “The electrical systems are all the same.”
The new line of loaders also features an upgraded hydraulic system.
“Before, we used gear pumps,” he said. “They worked all the time, which meant you were always using part of the power of the engine to turn the pump. Now, we’re using piston pumps with load sensing, so if you’re not using any hydraulic implements, the pumps are idle. You’re not taxing the engine to run the pumps, so you get increased fuel economy. As soon as you move a bucket or a boom, the pumps stroke and it gives you the flow of the pressure.”
The LH Series also features an ergonomically friendly operator cabin with bigger doors and wider windows.
Sandvik consulted widely with users around the world in designing the LH Series, flying maintenance managers, maintenance planners and operators from Vale Inco and Xstrata Copper operations in Sudbury and Timmins to Finland to solicit their input.
The introduction of the LH Series coincided with a decision to get out of the customization business.
“The list of options was getting too long, so we decided to standardize as much as possible,” said Maki. “If something needs to be welded onto the frame, we’ll do it,” but otherwise, customers who want something customized will have to do it themselves.
A team of Sandvik engineers conducted focus groups around the world to decide what was really needed and what to include in a standard package.
So far, Sandvik has sold five LH Series loaders in North America, including two to Xstrata Copper’s Kidd Creek operation in Timmins and one to Liberty Mines, also in Timmins.
Maki doesn’t expect to see fuel cell technology being used for underground loading anytime soon, but does foresee more use of tethered electrically-powered loaders, particularly as mines go deeper.
“Our biggest push now is for electric machines,” he said. “We have the largest range of electric loaders in the industry.”
Maki pointed to one huge block cave mine in Sweden that uses a dozen, 25-ton electric loaders. Goldcorp also has several electric loaders at its Red Lake Complex in northwestern Ontario.
Electric loaders allow for tramming to a distance of 200 metres and are ideal for truck loading operations. A reel attached to the loader keeps the power cable out of harm’s way, similar to the technology used in some vacuum cleaners, he said.
