The Goliath crane became the biggest of its type in Northern Europe when it was installed, with a capacity of 1,200t, a 154m span and a height of 120m (see Hoist, January 2018), enabling the shipyard to complete new orders for increasingly large cruise ships.

Mammoet has now revealed the approach it used to reduce the space required for the erection, to minimise disruption at the shipyard, as well as cutting assembly time and risk.

The limited working space on-site was one of the main concerns of the project, said Mammoet, because the Goliath crane needed to be erected parallel to ongoing construction work on the cruise ships in the yard.

The key to making the erection method space-efficient was using the legs of the crane as part of the installation equipment. The legs were erected first and then used as a gantry to raise the main girder without the need for additional equipment.

Mammoet used two cranes, a CC6800 and a LR110000, to erect the legs of the crane, which weighed 540t and 700t. Two further 500t-capacity crawler cranes were positioned at each side of the legs to install the strand jacks used for lifting the 2,500t main girder.

To increase safety and efficiency, Mammoet pre-assembled the strand jacks on ground level, enabling them to be lifted to the top of the legs in one operation. The company also designed various customised lifting tools, to make the installation and removal work safer and more efficient.