Shell is making significant capital investments in their Southern North Sea assets to ensure the integrity of the facilities for the remaining lifetime of the older producing fields, such as the Leman gas field. The Leman gas field is a natural gas field located 50 km from Bacton, United Kingdom. It was discovered in 1966. The total proven reserves of the Leman gas field are around 11 trillion cubic feet and production is slated to be around 200 million cubic feet/day.
Expansion of the Leman complex
To produce gas from the Leman field, Shell uses an offshore complex consisting of four platforms. This complex is still in production; however, the turbines on one of the platforms are nearing their expiration. That is why Shell decided to install a new platform with new turbines and auxiliary equipment. The new platform will contain a topside, jacket, bridge, and 4 piles, and it will be bridge-linked to the existing Leman complex. Wagenborg was asked to take care of transporting the piles and topside for this new platform.
Huge piles from Emden to Schiedam
The first part of this logistical challenge involved the piles, which had to be transported from the manufacturer in Emden (Germany) to Schiedam (The Netherlands). The piles – measuring 98 meters in length and 1.5 meters in width and weighing 180 tons each – will carry the jacket of the new offshore platform. The transport had to follow inland waters, since this route was much quicker and less risky than transport by sea. Because of the huge dimensions of the piles, this was quite a challenge! Wagenborg prepared her tug boat “Waterlelie” and the pontoons ”Wagenborg Barge 6” and “DH4” for this special job.
Both pontoons were outfitted with 24 transport saddles, which were chained to the deck. After the safety and toolbox meetings, the load-out of the piles could start. Self Propelled Modular Trailers drove the piles under the hook of a 600-tonne crawler crane configured with a super lift counterweight, which lifted the piles on the pontoons. After lashing the load, the tug and pontoons set a course to her destination. The transport arrived according to schedule in Schiedam, where the load was discharged by 2x400-tonne sheerlegs. This was Wagenborg’s first involvement in the Leman Project so far. The next challenge was thetransport of the new topside.
Topside towed offshore
The topside was transported on the deck of the Wagenborg Barge 9 by means of a RORO (Roll on Roll off) operation. Three double-connected 24- axle Scheuerle SPMTs were used to drive this heavy unit from the quay side on the pontoon. The topside measures 41 x 41.5 x 30 meters and weighs 3.275 tonnes. After securing the load on deck, the transport set sail to the final offshore location, where all components could be installed by a large deep-water construction vessel.