The Netherlands – The largest construction vessel in the world, Pioneering Spirit owned by Allseas, is getting its second unique jacket lift system.
The second lift system is capable of removing and installing complete offshore jackets weighing up to 20,000 t in one go. The Jacket lift system will further enhance Pioneering Spirit’s capability and provide the offshore energy market with a total solution for heavy lift work.
Hang-off and upend system
The upgrade work is ongoing for a several months. Recent activities have focused on the ‘hang-off and upend system’ (HOUS), the function of which is to raise and tilt the 170-m lifting beams. The HOUS comprises integrated upend systems, each with a pair of 50-m skid tracks fitted with push-pull mechanisms. Hydraulic cylinders drive the push-pull devices along the tracks, moving the beams up, while transom-mounted hang-off frame (HoF) assemblies function as hinges around which the beams rotate.
Simple system with ground-breaking technology
While the technology is ground-breaking, the way the system works is rather simple, Allseas explained. After cuts are made to a jacket’s foundation piles at seabed level, hoisting blocks suspended from the lifting beams raise the jacket at the main legs. The jacket is subsequently aligned with the beams, reclined, and skidded further inboard before transit.
Pioneering Spirit, formerly known as Pieter Schelte, was inspired by the offshore heavy lifting pioneer Pieter Schelte Heerema (1908–81). The vessel is designed for the single-lift installation and removal of large oil and gas platforms and the installation of record-weight pipelines.
Built at the DSME shipyard in South Korea, the vessel started offshore operations in 2016. The twin-hulled vessel is 382 meters long and 124 meters wide.