Underneath the floating platform , a riser support structure, RSS, was installed on the seabed. This RSS tower has a height of 110 metres. The structure was sunk vertically and pulled into the seabed by its own weight. That is why it is called a suction anchor. It comprises a rectangular U-frame measuring 70 x 40 metres, with the open end pointed downwards. Subsequently, the compartments were pumped out, resulting in a vacuum. This caused the anchor to pull itself further, firmly into the seabed.
After the construction period, the system was tested. To this effect, we designed a basin to serve as an underwater environment. After a number of days and nights of intensive testing, it turned out that everything functioned according to the design. Next, the Ichthys Suction Spread was assembled and installed in Batam, Indonesia. After that, the installation was transported to Australia on board the Aegir. Hydrauvision’s Suction Spread is a crucial part of the LNG-mining system.
The distance between the seabed and the platform is 250 metres. To bridge the remaining 140 metres, various umbilicals have been connected to the support structure. A pump frame has been installed on top of the suction anchor. This pump frame has a width of 6 metres, a depth of 2 metres and a height of 2 metres. It contains four water pumps, which have been modified by Hydrauvision Systems and provided with a hydraulic driving motor. The hydraumotors are driven by Hydrauvision Rental powerpacks, which are placed on deck. The powerpacks are connected to two umbilical winches, each of which has five umbilicals (press-return-press-return, leak). These hoses are connected at a depth of 250 metres by means of a Remote Operated Vehicle, or ROV.
The result: Hydrauvision has once again proven its knowledge and experience by designing and building the Ichthys Suction Spread. Another fine example of the excellent collaboration among the Hydrauvision divisions: Systems, Rental, and Services.