Jan 23, 2018
When it comes to staying ahead in the construction game, leveraging crane technology can mean the difference between success and failure.
Fletcher recently bought and erected the new German-built Liebherr 357 Luffing Crane on the $850 million Commercial Bay site. Reaching almost a quarter kilometre into the sky, it is the tallest tower crane in New Zealand and the latest in Fletcher’s long track record of adopting technological innovation earlier than the competition—a trait that extends all the way back to the company’s heady beginnings.
Auckland 1956 and works on the Greys Avenue Flats had numerous challenges. Fletcher won the contract and erected a self-raising tower Acrow Liebherr crane to build the 11 story block of 87 flats. It was the first crane of its kind in New Zealand, could be rail-mounted, and was equipped with an elevating boom, making it capable of covering the entire building site. The government architect took advantage of the crane’s capabilities by changing the exterior cladding to the more robust pre-cast concrete panels. Despite the challenges the job was completed on schedule.
Almost four decades later and Auckland’s Sky Tower was built using unique crane technology and techniques to overcome construction challenges never seen before in New Zealand.
The Sky Tower has come to define Auckland’s skyline. Standing 333.6 metres above its foundations and 326 metres above street level, it remains the tallest free standing structure in the Southern Hemisphere. The intensive, fast-tracked programme called for a concerted, collaborative effort from the client, architect, construction teams and of course—cranes.
At the time, the main Sky Tower crane was the tallest in New Zealand. Engineers used the crane to ‘climb’ each completed section of the structure. Once the tower was built, a smaller crane had to be constructed and attached to the upper part of the Sky Tower structure to dismantle the main crane. The small crane was dismantled into pieces small enough to be brought down the tower lift.
The project took two and a half years to build, was on budget and three months ahead of schedule.
Flash forward to 2017 and tower cranes now dwarf anything used before. Fletcher Construction’s newly purchased super crane—nicknamed Eenie as part of the four-crane operation on site—is almost a quarter of a kilometre tall and can lift 32,000 kilograms.
The crane is the slimmest, most powerful crane yet, and perfect for operating in tight city blocks where crane arms (jibs) must pass over each other. The crane is in use on the Commercial Bay project, bringing improved safety, load handling and other efficiencies.
Eenie, by the Numbers:
• 225 metres tall at full height
• Jib length 45 metres
• Able to lift 32 tonnes
• Will use up to half a kilometre of hoist rope
• Wired with 400 metres of power cables
• Can carry 38 tonnes of steel counterweights
• 42 adjustments can be made to the operator’s seat for greatest comfort
• It took 16 truckloads to move the first section of the crane from Drury in Auckland South to Commercial Bay in Auckland’s CBD
• One and a half days to erect Eenie using NZ’s biggest hydraulic mobile crane.