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54 E&MJ; • DECEMBER 2015 www.e-mj.com C R A N E S & R I G G I N G the crane performed more than 300 lifts weighing more than 75 mt during the three-year project. Syncrude had looked at crawler cranes for the job, but there wasn't enough working space for them nor the lifting capacity they needed. Never previously used (13 of the original units were sold to the Soviet Union for work on nuclear power plants), Syncrude's K 10000 was restored and fitted with upgraded control systems by Krøll in Denmark before being shipped to northern Alberta in 78 container-loads. Edmonton-based Northern Crane Services Group erected it during the bitter winter of 2007-2008, then won the contract to take it down again—a task that took its team just 43 days in 2011. The crane itself was mounted on a specially prepared con- crete foundation consisting of a 3-m-thick, 15-m-diameter pad supported on a series of 9-m-deep piles. The tower mast was preassembled in sections that were then trucked in to the erection site, with three crawler cranes being used for handling the mast and jib sections. For disassembly, Northern Crane Services again used three crawler cranes, including a 750-mt-capacity Manitowoc 18000 and two smaller Liebherr machines, a 220-mt-lift LR-1200 and a 300-mt-lift LR-1300. A key feature of the operation was that the crane had to be dismantled with the refinery in full oper- ation, with the company noting that it had used a number of innovative techniques to protect workers below as the plant remained live during the entire process. Industry Insights Since cranes are not a regular topic for review here, E&MJ; sought some insider information. Leigh Sparrow, publisher of the Vertikal.net group's Cranes & Access , offered these in- sights into current development trends, and advice on ensur- ing safe crane operation in the mining environment. When asked about recent developments in rough terrain cranes, Sparrow noted that RTs are typically larger now, with two axle models of up to 135 mt or more while the average size has increased from 22 mt 25 years ago to 65-75 mt these days. "There has also been a trend to offering RTs with longer booms—often taken from ATs," he said. "On ATs, crane booms have continued to get longer and there has been a greater emphasis on fuel economy and lower emissions. "One other major development that is rapidly becoming the norm is safer outrigger setup," he added. "It is now a requirement on new cranes for outriggers to be set properly before lifting begins, and manufacturers are taking this fur- ther with completely automatic systems that allow outriggers to be set up to suit the space available. "The information on beam extension and jack pressures is fed into the crane's control system, and a load chart calcu- lated to suit that particular setup. This is a major benefit in terms of safety and efficiency," Sparrow stated. Turning to the question whether a mining operation should buy its own cranes or rely on renting in, Sparrow said that key factors are the frequency of a specific type of lift, and the distance between the lift sites. "For example, a mine may well have a series of jobs that can all be sensibly covered with one 65-mt RT. As long as the lifts can be carried out within, say, a five-mile radius and there is a lift at least a couple of times a week, then it's probably best to buy that particular crane and rent in for rarer larger lifts." The "gray market" in cranes is one particular issue facing mines operating in some parts of the world. How can compa- nies reduce this risk? E&MJ; asked. "Either find a quality company and sign a contract almost forming a partnership," Sparrow advised, "or if there is enough work encourage a more distant company to set up a satellite depot at the mine. A final resort is buy-in a crane or two that will handle most of the lifting work." Following on from that, there is always the need for com- panies that are hiring in crane services to satisfy themselves that the cranes being provided are safe and their operators Installing one of the wind turbines at Rio Tinto's Diavik operation. (Photo Rio Tinto). This Krøll K 10000 crane performed more than 300 lifts weighing more than 75 tons as part of a Syncrude refinery upgrade project.