The SSCV Thialf is a semi-submersible crane vessel operated by Heerema Marine Contractors, and it was the largest crane vessel in the world until the SSCV Sleipnir became the largest in 2019.

SSCV Sleipnir is a semi-submersible crane vessel owned and operated by Heerema Marine Contractors. It is named for Sleipnir, the eight-legged horse ridden by Odin in Norse mythology.