K10000 rises again

?Canadian company Syncrude mines, processes and refines oil from the Athabasca Tar Sands in Alberta, Canada. The company recently began a project to reduce emissions at a greenfield site, and is installing equipment over a two-year span. The process equipment was intended to be installed in preassembled modular components, in loads weighing from 27t-91t, or even more.

"Mobile cranes would have required significant amounts of fill and matting just to begin the work," says Ernie Sheaves, crane and rigging specialist on the Syncrude Emission Reduction Project. Crawler cranes would not have been able to install the equipment at all, he adds.

Syncrude's solution was to use one of the largest-ever tower cranes, the K10000 from Danish crane manufacturer Krøll, located through US dealer Tower Cranes of America. It was chosen "because of being able to sit in a very small footprint and safely handle 95% of the required heavy lifts for the project," Sheaves says.

Krøll made a total of 15 units of the K10000 from 1976 to the late 1980s, says Krøll sales manager Niels Peter Sørensen. Thirteen of these were made for the Soviet Union for nuclear power plant construction, until the Chernobyl nuclear disaster in 1986 stopped construction completely.

Today, apart from one worn-out unit that was scrapped, all the other K10000s have been bought for lifting work, Sørensen says. All but the Syncrude unit are working at shipyards as permanently-installed dock cranes (see also p23). Customers include Statoil in Stord, Norway, Keppel in Singapore, ABG in Mumbai, India and Iran Marine Industrial in Tehran.

Syncrude's unit was built in 1983, and never erected, but held in long-term storage at the Port of Copenhagen.

He says that there was only surface rust on the equipment. "We were very pleasantly surprised by the condition of the structural components, after being exposed to the elements for such a long period of time." The structural components of the crane were blasted, inspected and repainted prior to shipment, Sheaves reports.

The crane also received a brand-new control system, with Siemens drives on the three principal travel motions of the crane for stepless speed control. Hoisting is controlled by a 140kW DC motor; slewing by four 14.6kW DC motors; hook trolleying by a 37kW AC motor. The crane also trolleys counterweight to compensate for loads, with three 8.6kW AC motors.

In Alberta, Syncrude had a new bed prepared for the K10000: a 3m-thick, 15m-diameter concrete pad supported by 13 metre-thick piles buried 9m deep. A total of 164 two-inch anchor bolts in a 25t assembly hold the crane into place. The crane is bottom-slewing.

Syncrude contractor Northern Crane Services was contracted to assemble, operate and maintain the K10000 during the two-year project. "Erecting the crane was a colossal job," Sheaves says. The crane shipped from Copenhagen in 78 closed, flat and open-topped containers. All the tower mast sections were preassembled away from the crane erection site with an LR 1160 crawler and an LTM 1080 mobile crane, both from Liebherr, and then trucked in to be set as required. Three crawlers were used for the main erection job: two Liebherr LR 1300s and a Demag CC2800 crawler. Jibs were assembled at the erection site after the tower was completed.

A 30-strong team of ironworkers put the crane up over the 2007/2008 winter. "We encountered the coldest winter in Northern Alberta in 15 years," Sheaves says. "The crane was erected over the winter when the temperatures were in the -20° C range (-4° F). There was a lot of dedication from the workers who erected this crane and they worked in some of the harshest winter weather conditions to accomplish it." The crane had not ever been assembled before being installed at the site. Only a few minor adjustments were needed to complete the actual fit-up of the crane, he says.

Northern Crane Services also installed a remote camera system to monitor the crane's winches, counterweight, travel and hook blocks. The crane has been operational since April 2008.

Sørensen at Krøll says that he expects to have orders for new K10000s, which would take about 24 months to build in the company's production of mainly special-application tower cranes. But Krøll is also planning something even bigger, he says, a 25,000tm crane. It could lift a maximum load of 400t to 57m reach, or 200t to 100m jib-end and mount on a 22m-span rail. He says that 60% of the drawings for this crane are complete, but he would not speculate on when all the drawings might be done. He adds that even if production began today it would take 36 months to make.

Although Krøll has not received any orders for this crane yet, Sørensen remains hopeful. He says: "Before Chernobyl, there was a demand for cranes like this. I'm sure it is going to happen again. It could be for shipyards or nuclear power plants." ??