Mammoet, which is the world’s largest service provider specialising in engineered heavy lifting and transport, brought home the award in the jobs over USD 2M category.
A spokesperson for Mammoet said of the project: "In December 2013, the world’s largest TBM ceased operation 35m underneath Seattle after hitting a steel pipe damaging the seal ring and bearing block. It could
Neither be repaired underground, nor could it be easily retrieved. Mammoet was contracted to lift the 2,000t cutterhead from a 35m-deep shaft for repair and lower it back down once repairs were complete.
"Mammoet successfully and safely completed the task by designing and fabricating a unique custom-engineered gantry tower with the world’s first hydraulic equalisation system, which evenly dispersed the forces exerted by lifting and tilting the load. It was a necessary innovation, as the gantry tower would stand on existing concrete piles used for tunnel stabilisation, which were not designed to support loads at height. The result was a ‘self-balancing’ tower gantry that ensured the stability of the entire lifting operation."
