STAVANGER, Norway – The North Sea Giant vessel has begun offshore installation of the modules for the Åsgard subsea gas compression project in the Norwegian Sea.
This is designed to extract a further 282 MMbbl from the Åsgard field.
According to operator Statoil, 22 modules will be installed and connected at a water depth of 300 m (984 ft) to form two identical compressor trains, each weighing 1,500 metric tons (1,653 tons). They will be housed in a large subsea frame installed on the seafloor in summer 2013.
All the modules are being shipped from Vestbase in Kristiansund, having undergone commissioning and testing in Egersund.
They vary in size. The smallest modules – up to a maximum weight of 70 metric tons (77 tons) – are being lowered through the vessel’s moonpool.
Larger modules will be installed using the ship’s crane handling system which can lift loads of up to 420 metric tons (463 tons) and which can operate in waves up to 9 m (30 ft) high. In this case, the modules are guided into position subsea via an ROV and cables.
Installation sequence has been planned to allow start-up work to be performed on the first compressor train while installation of modules for train 2 continues.