35 JUNE 2023 WorldWide Drilling Resource® A Closer Look - How Large Equipment Gets into a Mine Adapted from Information by Caterpillar Mining Ever wonder how the massive mining machines make it to their underground destinations? A lot goes into putting the enormous pieces of equipment to work in a mine, from selecting the ideal machine for the job and shipping it via land or sea, to assembling and commissioning it on-site. The process can become even more complicated when the mine is underground - especially when it’s 630 feet below the surface and only accessible through a 60- by 70inch shaft. The only way to get equipment into the mine is to disassemble, lower, and reassemble it underground. Since 1959, U.S. Gypsum’s (USG) Sperry underground mine in Iowa has produced gypsum, an important mineral for a variety of products. The mine produces over 650,000 tons of raw gypsum annually. The room and pillar mine has an average ceiling height of about ten feet. Gypsum is mined using the drill and blast method, then the rock is hauled to the mine’s crusher. “The physical size of the mine has always been a limiting factor for selection of mobile equipment,” explained Dennis Hollingsworth, former mine general foreman. Over the past ten years, the mine has successfully commissioned three Cat® R1600 underground loaders. When it came time to add another large piece of equipment to its underground loading and hauling fleet, they didn’t hesitate to select the Cat AD30 underground truck. USG had worked with Altorfer Cat, a dealer near Mediapolis, Iowa, before. In fact, several of the Altorfer team members responsible for the first mine transfer were also on hand for this one, including sales representative Jeff Krug and field technician Chris Wolf. After the successful implementation of the mine’s R1600 fleet, Altorfer developed best practices for the mine transfer process and shared them with other dealers around the world. Taking advantage of lessons learned in the past, the Altorfer team spent several weeks planning and collaborating with the Sperry team before beginning the latest transfer. The process began with the AD30 arriving at the Altorfer Cedar Rapids facility where it was adapted to the specific requirements of the mine. The bed was removed and modified to meet the 6-foot height requirement for loading and the standard tires were replaced with a low-profile tire to meet the maximum height requirement of the mine. It was a cold November day with temperatures dipping below -2ºF (-19ºC) when the machine arrived on the surface of the Sperry mine and the technical team began their work. Joining Wolf were two Sperry employees who also worked on the R1600 mine transfers: Doug Edle, the mine maintenance supervisor; and A.J. Kuisle, a technician. The team removed the rear axle, all the cooling lines, and wiring harnesses from the rear frame, then separated the rear frame from the front frame. Then it was time to tackle the front frame, removing the cab, engine transmission, as well as the front axle, and lowering them into the mine. The team was then able to remove the fire suppression system and wiring harnesses, along with the hoses and valves. Once everything was removed from the front frame, the team welded on fixtures for lining up the frame pieces for reassembly. The cutting began with oxyacetylene torches and an air arc to cut the frame into smaller pieces to fit down the shaft. Once all the parts and pieces were down the shaft, the AD30 was cleaned and the welding team put the frame back together. Now it was time for Wolf and Kuisle to reassemble the rest of the machine. “It took about three weeks to get it back together and running,” said Wolf. “We were very particular to make sure that everything was assembled correctly, that there were no hoses or wires rubbing. Then we started it up and installed the bed and made sure everything was working correctly.” Before handing off the keys, the Altorfer team took it for a test drive. “We drove it through the mine to make sure it would fit everywhere it needed to go. We went to the north and south crushers and made sure it could successfully dump at either place.” When the testing was complete, Wolf provided training to the employees who would be operating the new truck. About 4½ weeks after the mine transfer process began, the AD30 was off to work. Editor’s Note: In between our print issues, the WWDR Team prepares an electronic newsletter called E-News Flash by WorldWide Drilling Resource by WorldWide Drilling Resource®. This newsletter is filled with articles not included in our print issue. Based on readership, this was the most popular article of the month. Get in on the action and subscribe today at: worldwidedrillingresource.com MIN Most of the gypsum mined at the Sperry underground mine is used in the on-site manufacturing plant, where USG makes Sheetrock® brand wallboard. July 29-31, 2023 ~ Look for the WWDR Team at Booth #301 at the South Atlantic JUBILEE at the Myrtle Beach Convention Center in Myrtle Beach, South Carolina. Visit www.jubileewatershow.com See more events at worldwidedrillingresource.com online issue. Are you planning to go? WorldWide will be looking for you!
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