Grove GTK1100 tandem lift

Two Manitowoc Grove GTK1100 cranes worked in tandem to erect a new chimney for a coke production facility in the SaarLorLux region of southwest Germany. The plant is owned by Dillinger Hütte, one of the leading European producers of heavy plate steel sheets, which are generally used for the construction of heavy machinery and shipbuilding.

Stahlbau Schaefer, the main contractor on the job, consulted AKV Schirra Schuch, a local crane rental company, to find the best lifting technology for the job.

Roman Schirra, AKV Schirra Schuch general manager, said the contractor first considered a crawler crane but, after surveying the site, the company decided on a Grove GTK1100.

"Our company attended a launch event for a GTK1100 owned by rental company Wiesbauer," he said. "We immediately recognized the benefits of the GTK1100 concept for this project and secured the crane for it. The lower transport costs, ability to rig the crane in confined spaces and huge lifting capacities even at spectacular heights, made the GTK1100 a good choice for Dillinger Hütte."

The chimney had to be erected by lifting each segment into place, one on top of the other. Considerable planning was required, however, as the jobsite construction area was limited by confined spaces and several pipe bridges which had to be avoided.

Most of the lifts were completed with just one GTK1100, but Wiesbauer realised that the crane did not have the capability in the load chart to lift the final segment. The segment weighed 38 tonnes, while the GTK1100 has a capacity of 34 tonnes at full extension.

By designing a detailed three-dimensional drawing of the final lift, a team of engineers gained an additional 1.7 m height by having two GTK1100 cranes working in tandem. Stahlbau Schaefer then hired a second GTK1100 from Breuer & Wasel GmbH, another crane rental company.

For the final lift the load, including hook block, lifting accessories and rope, weighed about 41.6 tonnes. It was lifted at a radius of 12 m to a height of 140.2 m.

Dillinger Hütte will invest US$254.2 million in the complete refurbishment of the coking plant. The new facility will incorporate state-of-the-art technology, while taking account of modern environmental requirements, said the company. The overall project is expected to complete in 2010.