Offshore platform dismanteled and removed from the North Sea                 

Date January - June 2008

Used equipment welding material, crane pontoon, scaffolding

Special features All work undertaken offshore

On the instructions of a client, DDM Oil & Gas, in conjunction with DDM Demontage, removed the gas satellite platform P14-A. This platform, which was no longer in use, was located in the Dutch sector in the south of the North Sea. DDM’s tasks consisted of cutting, dismantling and welding. The upper deck was to be reconfigured for further use, while the drilling deck and the jacket(the legs on which the platform stands) were to be scrapped.

A sea-going crane pontoon was required for the first phase of work, during which the upper deck was prepared in such a way that it could be removed in one lift. These preparations included the installation of a new lifting eye on the upper deck and weld inspections to check the condition of the existing lifting eyes. This was all necessary to prepare for separating the deck structure (upper deck and drilling deck) from the jacket.

The crane pontoon was positioned alongside the platform mantel so that the team could transfer to and from the platform using an Ampelmann access system. The pontoon returned to Rotterdam for he 30 metre high main crane jib to be installed. When it returned the rigging was secured to the lifting eyes and the large crane was used to pre-tension the cables and to cut the legs loose. The total weight of the upper deck was 740 tons.

The crane pontoon ensured that the upper deck was held fast in the blocks for the trip to Rotterdam where everything was transferred to a transport ship. The drilling deck was separated from the upper deck in the Waalhaven harbour. The drilling deck was then scrapped, while the upper deck was taken to the NAMI yard where it was modified for re-use on another project.