December 15 - Swiss heavy lift and specialised transport provider Welti-Furrer Pneukran & Spezialtransporte has used a Terex TC 2800-1 lattice boom truck crane to lift three Enercon E-92 wind turbines at the Gries Pass in the Swiss Alps.

With an altitude of 2,500 m at the site, Welti-Furrer decided to use its TC 2800-1 truck crane due to its manoeuvrability and gradeability, as well as its flexible outrigger system.

The truck crane, its assist crane and 15 transportation vehicles first had to make their way up to the site, navigating gradients of up to 18.5 percent and various narrow passes.

The journey required entire paths and setup areas to literally be cut out of solid rock en route, or even cleared by explosives in advance.

On arrival at the site, the crane was set up with a 14 m x 14 m outrigger area and configured with a counterweight of 200 tonnes. The crane was equipped with a 90 m main boom and a 12 m jib, which was suitable to erect the turbines' 84 m high towers at a radius of between 22 and 25 m.

The wind turbine components had a maximum weight of 64 tonnes.

Welti-Furrer's project manager Werner Häfliger explained that the challenging project was made more complex by the adverse weather conditions.

"That day, the pass was blocked by snow, which meant we couldn't access the site," he explained. "We made sure to take full advantage of every single second of wind-free time we got, which enabled us to finish things on schedule despite the adverse conditions and hand over all the turbines on time."