The world’s largest semi-submersible crane vessel, The Sleipnir, is currently at the Port of Walvis Bay.
The semi-submersible crane installs and removes subsea equipment, decommissions and carries out heavy lifting operations in offshore oil and gas facilities.
Sleipnir was constructed in 2019 and is owned and operated by Heerema Marine Contractors. Sleipnir, named after Odin’s eight-legged horse in Norse mythology, boasts two massive revolving cranes built by Huisman Equipment B.V., each with an impressive lifting capacity of 10,000 tons. These cranes can work in tandem, achieving a remarkable joint lift of 20,000 tons.
The Singaporean Sembcorp Marine started constructing the vessel in 2015 and completed it in 2019.
The vessel’s design deviates from traditional semi-submersible crane vessels, opting for a platform supported by eight symmetrical columns (four on each side) with streamlined pontoons. This innovative design minimises pitching in rough seas, enhancing stability. The ship’s ballast tanks and LNG storage are ingeniously integrated within these columns, each at an impressive height of 23.75 meters.
Sleipnir’s cranes, supplied by Huisman, are mounted on tubs with an overall boom length of 144 meters.
The slewing system, allowing the cranes to rotate, features the world’s most giant bearings at an astonishing 30 meters in diameter. This design choice ensures robust and efficient crane operation. The crane house is securely anchored to the foundation using an intricate arrangement of 1100 bolts, each exceeding 82mm in diameter, contributing to the vessel’s structural integrity.
*Various sources
