SEPTEMBER 2, 2014 — Damen Shiprepair Vlissingen, the Netherlands, has completed a major upgrade of a Rowan Companies plc jack-up in 30 days less than initially projected by the client.
The scope of the project involved the extension of the three legs of the Keppel Fels "N" class drilling rig Rowan Viking by 10 m to 180 m, a five-yearly special periodic survey and bringing the rig up to standard for the AoC (acknowledgement of compliance) certification required by the Norwegian authorities.
The Vlissingen shipyard, which is part of Damen Shiprepair & Conversion, was chosen for its large size, convenient location on the North Sea and its suitable quayside. It also has previous experience in converting jack-up rigs, most recently the Atlantic Amsterdam and Atlantic Labrador.
Rowan had projected that the work would require 130 days, but through the application of innovative project planning techniques and highly specialized equipment Damen was able to reduce this by nearly 25 percent.
Damen Shiprepair Vlissingen adopted an entirely new approach to this kind of project.
A project execution plan was drawn up that allowed the three aspects of the contract to be undertaken simultaneously. To enable this to happen, changes had to be made both to working practices and to the organization of the shipyard itself.
The use of a Mammoet PTC crane and Palfinger’s unique JUMP system were critical elements of the plan.
Palfinger JUMP system
The PTC crane was delivered on over 100 trucks and was erected to a height of 200 m on special permanent foundations installed to bear the immense loads. This allowed the rig to remain at sea level and the leg extension pieces to be lifted directly from the shore on to the legs for installation. Palfinger supplied the safe working platforms that allowed engineers to move up and down the legs, at heights of up to 160 m, for fitting and welding.
As one of the first projects of this type that Damen Shiprepair Vlissingen has undertaken, there was a steep learning curve for all involved. However, with the experience from the Rowan Viking refit and the creation of finely tuned project plans and work practices, plus the strong relationships with partners Mammoet and Palfinger, the team at the yard is confident that it will be able to further reduce the time required on similar undertakings.
Damen Shiprepair Vlissingen is currently in discussions with two rig-operating companies regarding similar leg repair and extension projects.