Strategically located Gibraltar shipyard Gibdock has continued its run of technically advanced offshore support vessel repair and maintenance projects, securing a contract involving a returning customer. The Viking Vanquish, a high capacity 3D seismic survey vessel operated for CGG, has undergone a 21-day program of works, leaving the shipyard’s drydocks in mid-September prior to sea trials.
Based in France, CGG operates 23 seismic survey vessels, after acquiring Fugro’s geoscience division earlier this year - claimed to be the largest high-end seismic fleet in the industry.
The scope of work carried out on Viking Vanquish included a tailshaft withdrawal and the full overhaul of the shaft, couplings, liners and related equipment. This complex process required cutting away a section of the stern tube to gain access.
“This was certainly not a straightforward or standard job,” explained John Taylor, Gibdock operations director. “Usually the couplings can be found in the engine room, without access complications. This was not the case on this project, but we nonetheless managed to finish on schedule.” Gibdock also machined liners for the tail shaft, which were not supplied pre-machined.
The 93.3m long, 8,621grt Viking Vanquish (built 1998) is owned by Norwegian company Eidesvik and was converted for seismic operations in 2007. Towing 12 x 8km streamers as standard, the vessel is capable of acquiring high quality data in all conditions.
Gibdock also carried out a series of load tests on the Viking Vanquish’s many winches and eye-plates, as well as a range of other machinery and pipe works. The yard renewed propeller blade seals and blasted and painted the vessel’s exterior.
Are Skaanevik, technical superintendent for ship manager CGG Eidesvik, highlighted another notable aspect of the project as using a cleaning product from Ultraclean AS, believed never to have been used before in shiprepair. The product, a combination of gel and chemicals, was applied to remove corrosion on Viking Vanquish’s gun-deck and cranes then washed away with water, to prepare surfaces for coating. CGG, Eidesvik and Gibdock expressed satisfaction with the results of using a product that may provide an environmentally-friendly alternative to conventional blasting.