Transporting a 100-tonne machine to its job 750 meters below the Earth’s surface is no simple task. But for K + S Rohsalz, which operates several salt mines across Germany, it was worth the effort to make sure a Cat® wheel loader handled the critical task of transferring 33,000 tonnes of raw salt.

“This wheel loader is the best machine we have ever seen,” says Peter Budesheim, head of machine technology at K + S’s Hattorf mine, describing the Cat 992G the company purchased back in 1999. When the time came to replace that machine, which had accumulated more than 32,000 operating hours, K + S naturally turned to the 992K. But configuring the new loader for its underground assignment—and then getting it down the mine’s material shaft—required a team effort.

Specially configured for underground work

Working together, K + S and Cat dealer Zeppelin customized the 992K for its challenging work deep below ground. That included installing a high-pressure fueling system that could fill the machine’s tank with 1,300 liters of diesel in just 10 minutes—along with a protective ventilation system to keep fine salt dust out of the operator compartment. Thick armored glass panes, on-board fire extinguishers and a safety system with a rear-view camera and warning alerts were also added to help protect the operator.

In addition, despite good ventilation systems and “weather doors” at the Hattorf mine, the 992K had to meet strict emissions standards.

“The latest 12-cylinder engine on the basis of Stage IV, which no other manufacturer of construction equipment can offer on machines of this size, contributes to remaining low exhaust emissions,” Budesheim says. “We invest in the best technology the market has to offer.”

Custom-made bucket

Finally, Zeppelin equipped K + S’s 992K with a custom-made bucket, designed and manufactured by Cat Work Tools,  with a payload of 32 tonnes and a capacity of 22.5 cubic meters. Hinge plates are integrated into the body, increasing load volume and dump clearance, and boomerang plates help prevent blade deflection and cracking. The bucket features a spade edge for better material penetration and retention, as well as special pin-hole covers to prevent material from penetrating the pins and bushings.

A long, careful trip down the shaft

Properly configuring the 992K for its underground assignment was just the first step. To get the 15-meter-long, 5.3-meter-wide, 5.0-meter-tall machine down the Hattorf mine’s 4.5-meter-wide material shaft, workers at Zeppelin’s Kassel branch had to dismantle it, then package the pieces for transport. Large components like the frame, engine and cooling unit were delivered whole. The loader’s custom bucket came in two parts due to its large size.

Ultimately, 20 individual components each weighing more than three tons, plus more than 50 pallets of smaller components, were carefully transported down the mine’s material shaft, where they were reassembled—successfully and safely—by a team of Zeppelin and K + S employees.

“Due to the support provided by the service, it was not difficult for us to choose Cat,” Budesheim says. “Zeppelin ensured fast reaction times, even on the weekend.”