Wintershall Noordzee B.V. has contracted Scaldis Marine Contractors NV for the installation of the L6-B platform, in the Dutch sector of the North Sea, in block L6. The water depth on the development location is 35 m. The location of the platform is situated 25 nM North West of Terschelling, The Netherlands.
In a joint effort between Wintershall and Scaldis a methodology was developed with a prime focus of minimizing the duration of the offshore activities. After all, a reduction of the duration of the offshore activities automatically leads to a reduction of risk and overall costs.
The newly developed methodology consists of the transport and installation of a complete platform to site.
The complete platform will be picked up from a quayside in Rotterdam using the Heavy Lift Vessel Rambiz with a capacity of 3,300 T. A special tool has been developed in combination with Innovative Input. The tool will enclose the platform mast, via hydraulic opening doors. Thereafter rigging will be connected via hydraulic shackles to the bottom part of the foundation, the suction cans. The structure will then be lifted from the quayside and transported, in the hooks of the HLV Rambiz, to the installation side, North West of Terschelling.
Upon arrival on site, the HLV Rambiz will moor in the correct position and orientation. The complete platform will be lowered until the suction cans reach the seabed. Scaldis has subcontracted Suction Pile Technology to execute the actual suction operations. By reducing the pressure in the voids inside the suction cans, the suction cans will penetrate into the seabed until they have reached the target depth of 10 metres below seabed. This methodology is fast, efficient and environmentally friendly operation. Upon completion of the suction operation the platform inclination will be verified. Thereafter the rigging connection will be disconnected, the hydraulic spreader bar door opened and released from the structure
Reference: Scaldis Salvage & Marine Contractors