As fleet managers are painfully aware, undercarriage maintenance and replacement costs can be one of the biggest expenses when it comes to running crawler excavators. This is especially true if you’re working in large areas with rough terrain.
I’ve seen a number of products and strategies to deal with the wear and expense, from beefier track systems and special shoes offered by manufacturers to simple jobsite directives reminding operators to watch what they travel over. But I’ve never seen this:
Talk about reinventing the wheel!
Known as the Sleipner system, it uses wheeled dollies and the back of a mining truck (or perhaps an ADT) to effectively turn the excavator into a wheel-mounted trailer that can be towed around the site at around 10 times the travel speed of the excavator under its own power.
Faster travel with no stress on the undercarriage? It’s a win-win.
Once at the next job, the excavator operator simply raises the boom, releasing it from the dump body, and drives off the wheeled dollies.
In the particular application that drove the need, a Lafarge limestone quarry in the U.K was operating 12 benches, each about 49 feet high. Because they covered three geological periods of Carboniferous limestone (I bet you don’t have that in your backyard) with differing silicone content, they all had to be mined simultaneously.
The content was high in the top benches, extremely high in the middle and low at the bottom. Cement from this source had to be a constant mix of the mined material – a blend from all three types of limestone.
There was also a requirement that as each bench is processed, the faces had to be dressed. Doesn’t sound too bad until you consider that this particular quarry blasts three or four times a week, with each blast producing 16,000 to 21,000 tons.
So Lafarge employed an excavator with lots of loading power for the large volume of material and good reach to do the dressing.
Ready for the kicker? In a 385-acre quarry, the excavator had to be all over the place.
Imagine the undercarriage wear and tear.
This is where Finnish manufacturer Sleipner came in. Lafarge used the Sleipner 970 transport system featuring a pair of double-wheeled dollies that fit on excavator tracks. This particular system works with excavators from 33 to 132 tons.
Sleipner’s original eight-wheel version is for excavators from 209 to 440 tons. That’s actually where the company got its name – after Sleipnir, the mythical eight-legged horse that carried Norse god Thor into battle.
Maybe the dollies should be decaled with lightning bolts.