The high-spec. pipelay spread, capable of installing flexible pipe using a vertical-lay system and rigid pipe by the J-lay method using the same tower, is being designed and manufactured by Huisman-Itrec, also in the Rotterdam area.
The Seven Seas is the second pipelay vessel being built by Merwede for Subsea 7. The first, the Seven Oceans, is currently undergoing sea trials at the moment at Huisman-Itrec, and will be delivered in a few weeks, after which it will departs for the Gulf of Mexico to work on the Chevron Blind Faith project.
The Seven Seas is 157m long and the top of the pipelay tower will be 60m above sea level. The vertical-pipelay system has a top tension capability of over 400 tons, and there is a storage capacity for flexible pipe based on two 1250-ton carousels below deck and a 3000-ton carousel (or multiple reels) on deck. The vessel will have a very large aft deck, a 400-ton deepwater crane, a built-in deepwater ROV spread, and a comprehensive survey system.