Mammoet has successfully transported transition pieces for the Îles d’Yeu and Noirmoutier offshore wind energy project.
Mammoet was tasked with assisting with the marshalling, movement and temporary storage of the transition pieces by one of its clients, BOW Terminal, in Belgium.
The transition pieces, weighing 400 tonnes and measuring 30 m in height and 6 m in diameter, arrived by barge in fours from Antwerp and were lifted onto the quayside by a 1,200-tonne crawler crane before being placed onto temporary concrete supports.
Each TP was then collected on a 2 x 14 axle line configuration of SPMT and moved to a temporary laydown area. There, they were placed on supports waiting to be called off, after which they were simply lifted and driven back from the storage area to a setup location on the quayside.
Mammoet explained that in the past, the SPMT trailers would be fitted with a gantry system that is constructed and parked over the top of the transition piece so it could be lifted from above. In this instance, Mammoet utilised a new attachment for the SPMT that essentially turned it into a giant forklift, allowing the units to be picked up more quickly and easily from underneath.
“BOW Terminal came to us and asked if we had a system like this available. We explained that there was already a concept in progress, and we just had to develop it. This took around four months, including all fabrication and testing – which was carried out at BOW Terminal,” said Lars de Haas, project manager at Mammoet.
With a heavy lift capacity of 800 tonnes, the TPH800 ‘forklift’ has two main cross beams that sit on top of two lines of SPMTs and from these hang two lower beams, which act like forklift forks.
As the SPMTs approach the transition pieces, the front cross beam lifts like a parking barrier to allow the lower beams to be slotted underneath them. Once in position, the front beam lowers and the piece is firmly locked into place by pinning both cross beams to the lower beams.
“The crane was used here because bigger barges were needed in case of a roll-off, and we had to allow for the tide. In Vlissingen, there is about four metres of tide. Using a crane, you are tide independent and can carry out work 24 hours a day if needed,” de Haas added
Îles d’Yeu and Noirmoutier will be the the fifth offshore wind farm to be commissioned in France. The project is 12 km from the island of Yeu and 16 km from the island of Noirmoutier, off the west coast.
