August 1999 Vol. 220 No. 8  Offshore

Robert E. Snyder,  Editor

New construction vessels, subsea activity surge

Recent press releases describe plans for three new work vessels — a platform decommissioning vessel, a deepwater multi-service vessel and a deepwater pipelay / construction vessel. A new company, Excalibur Engineering bv in Delft, the Netherlands, has announced development of the platform decommissioning vessel Pieter Schelte, for which the first concept was launched by Allseas in 1987. Originally intended to be used for platform installation, the present design is primarily for removal of topsides and jackets. It will be the first vessel able to perform single-action lifting operations on this scale, adding a new speciality to the offshore industry.

The vessel will be a large catamaran consisting of two rigidly connected, 870-ft-long tankers, equipped with a heave-compensated system, to lift topsides / jackets between the vessel’s bow sections. Lifted structures will be taken by the vessel to sheltered water and placed on cargo barges which fit between the bow sections, after which the structures can be towed to decommissioning yards.

The vessel is intended for worldwide use, and can work in hostile areas such as the North Sea, and be suitable for all existing-size topsides / jackets. Topside and jacket weights up to 45,000 mt and 25,000 mt, respectively, can be removed in one piece. The company expects to purchase the tankers for conversion later this year, and plans to have the vessel operational in 2002. The vessel in named after Pieter Schelte Heerema, who passed away in 1981.

Cal Dive International, Inc. says it will proceed with construction of the Q4000, a newbuild, ultra-deepwater multi-service vessel. The semisub will have a unique column-stabilized design combining station-keeping capability with large deck space (15,000 sq ft), significant deckload capacity (4,000 t) and high transit speed (12 kt). It will be configured to work in deep water, and carry out construction and well-servicing operations in worldwide environments. Introduction of the vessel will be in mid-2001.

In water depths to 10,000 ft, the vessel will be capable of: well completion / tree setting; template / module installation; flowline and umbilical lay; well intervention; steel pipelay (J-lay or reel-lay); life-of-field support, repair / maintenance; and decommissioning.

And Coflexip Stena Offshore has announced that it has signed a letter of award with Hyundai Mipo Dockyard for construction of its newbuild ultra-deepwater pipelay / construction vessel. The award targets delivery for January 2001. This multipurpose vessel (630 ft long, 105 ft wide, with 52,000-t displacement) has been designed to lay rigid and flex pipe, and umbilicals down to 8,000+ ft. Main features are storage capacity of 8,000 t, transit speed of 13 kt and a heavy lift capability of 400 t. The newbuild hull selected is based on the Gusto10,000 design.

The vessel will be the only one of her class able to lay flexible as well as rigid lines in ultra-deep water. The unique pipelay equipment will comprise two large reels for rigid pipe, two carousels for flex pipe and umbilicals, and a tiltable ramp, equipped with tensioners, located over the central moonpool for laying both rigid and flex lines.

Subsea activity increasing. As reported in the July 8, Subsea Engineering News, subsea may be the place to be in the new millennium. The report says analysts Infield Systems and Douglas-Westwood are forecasting the spending of $44 billion over the next five years, including drilling / completion ($20 billion) and flowlines ($15 billion). In this period, the subsea production market will double from 1998 levels. This year alone, subsea developments valued at $7 billion will come onstream; then, after a decline in 2000, will grow again to nearly $12 billion by 2003.

Data for the forecasting was drawn from the Subsea Online database, which shows the annual rate of subsea completions peaking in 1999 at 287, falling to 239 in 2000, and a strong increase to 404 in 2003. From 1999 to 2003, there is potential for 1,604 subsea wells to come onstream worldwide — including 700 in NW Europe, 380 in Latin America and 213 in North America. Five factors are driving this growth: higher oil / gas prices; reduced subsea development costs; a rise in small reservoirs within reach of host platforms; increased deepwater developments; and new technology.

Another report from the Research Council of Norway’s Offshore 2010 newsletter says the country — with potential to take advantage of subsea developments with growing satellite field numbers — is promoting a new R&D strategy zeroing in on subsea. Offshore 2010 — the Council’s new R&D program for the petroleum sector — is designed to meet the challenges of subsea production in increasingly deeper water, multiphase transport over long distances and downhole operations. During the first-half year, the program has received more than 100 applications for project funding.

The Council’s new strategy for user-controlled R&D sets up two main priorities: 1) downhole and underwater processing and transport; and 2) innovation and commercialization of small and medium-sized enterprises (SMEs).

Well-stream treatment close to the reservoir, in the well or on the seabed, combined with transport, has many advantages. Such technology opens new possibilities for more efficient use of energy and for reduction of pollutant emissions (CO₂). It will, in addition, play a key role in developing new production concepts on the Norwegian Continental Shelf. Well-stream treatment that makes transport over long distances possible will decide location / use of field installations, transport networks and infrastructure offshore and onshore.

These technologies should reduce development / production costs, improve oil recovery and help develop resources far away from existing infrastructure. Offshore 2010 will concentrate on initiating and organizing high-risk projects which, in a ten-year perspective, can result in such multi-technology innovation opportunities.

The Norwegian oil / supply industry is likely to benefit, in an international context, from technology development taking place off Norway. The Council’s objective is to back this opportunity through support for innovative and commercially directed R&D, involving primarily small and medium-sized enterprises.

Copyright © 1999 World Oil
Copyright © 1999 Gulf Publishing Company