Oct. 2000 Vol. 221 No. 10  Drilling

Robert E. Snyder,  Editor

European offshore spending; ONS innovations

Total capital expenditure for European offshore areas is expected to increase from $9.5 billion in 2000 to $12 billion in 2001 – 2002, before beginning a long, slow decline, according to the new Offshore Europe Report from energy industry analysts Douglas-Westwood and offshore data specialists Infield Systems. The report says that, over the next five years, European offshore capex will total $53 billion, with $46 billion split almost equally between Norway and the UK.

The study indicates Europe is the world’s largest offshore producer; 438 operating fields produce 6.5 MMbopd and 20 Bcfd gas. In the next five years, development of oil/gas reserves totaling 14 Bboe is expected in this huge area stretching from the Arctic to the Mediterranean; but the lion’s share will be in the UK sector (7 billion) and Norway (5 billion), with the other 2 billion divided between seven other countries’ offshore areas.

Unique in examining the offshore industry from macro-economics and the role of governments to the detail required by contractors, the study forecasts that the period through 2004 will result in installation of: 152 fixed platforms; 17 floating production systems; 724 subsea well completions; 3,000 km of control umbilicals; and 11,000 km of pipelines and flowlines.

Report authors note that the upturn long awaited by the offshore industry is beginning; and 2001 is likely to be a busy year. But offshore Europe is now a mature region dominated by prospects for large numbers of small fields. Subsea well tiebacks are the most favored method of exploiting the numerous small-field prospects that exist in the North Sea. Europe already has more subsea wells installed than any other world region.

Field depletions and removal of installations are due to become major issues in future years. Over the period 2000 – 2004, 111 fields may reach the end of their lifetimes, resulting in 43 platforms and 163 subsea wells requiring removal

Regarding present production capacity, just seven companies (Statoil, Norsk Hydro, BP Amoco, Shell, Phillips, British Gas and Agip) account for over 70%. But the share of offshore activity taken by the majors is due to decline as small fields become the norm. The future belongs to companies which can develop cost-effective approaches to develop reserves of 50 million barrels. And a further opportunity arises for small players in taking over the operations of declining fields from the majors – depending on settlement of the decommissioning issues.

For more information, contact John Westwood at Douglas-Westwood: Fax: 44 1227 832092; Email: admin@dw-1.com.

ONS drilling innovations. Walking around the ONS 2000 exhibition in Stavanger revealed, to this editor anyway, several innovations in the drilling department. While these may not be new to the entire industry – in fact some have already been applied successfully – they are certainly interesting. Here’s a summary of three of them.

   Slimhole drilling with a compensated rig. Offshore & Marine / Mercur, Sandnes, Norway, demonstrated the advantages of the Mercur Compensated Drilling Rig (CDR) which can improve slimhole drilling. The basic concept is that when placed on a mono-hull vessel, the system will compensate the entire drill floor so that it is kept steady in relation to the seabed. The advantage is that the drillstring will not move in the hole even when drill pipe is set in the slips. Moreover, accurate weight on bit can be achieved with less than 1,000-lb variation.

Mercur says the system creates the same drilling environment offshore in deeper waters that the system would see on land or a fixed platform. The surge and swab effects of reduced annular clearances in slimholes, while tripping or with transferred vessel motions, are eliminated. And accurate bit weight can be maintained.

Compensating an entire drill floor doesn’t appear easy, but when size and weight of the equipment to be handled in the drilling process is reduced significantly, there is no additional weight to be accommodated in compensating the whole drill floor, than previously handled with a conventional drillstring compensator. The system also is adaptable for coiled tubing drilling and subsea well intervention, as well as underbalanced and dual-density drilling.

For more details contact Mercur in Sandnes, Tel: 47 51 60 24 59, Fax: 47 51 60 25 10. A report titled "Slimhole drilling and well intervention" describes slimhole advantages and application of the CDR.

   Improved casing running. National Oilwell Hitec offers a brochure on its pipe handling system, which includes the National Oilwell Casing Processor. Representing an efficient, time saving solution when running casing stands in the hole, the new device provides four essential functions:

• Soft stabbing to prevent thread damage
• Filling tool. Prevents spillage of expensive fluids, and secures effective filling operation
• Spinning-in and makeup tool for casing, excludes the use of expensive casing tongs on the drill floor
• Mud circulation tool. Allows for circulation of mud while running casing in the hole.

The device is a compact combination tool attached to the top drive while running casing. For more information, contact National Oilwell and ask for the pipehandling office.

   BHA oscillator. A downhole system offered by Andergauge Drilling Systems called the AG-itator improves movement of the BHA through the hole, especially in oriented drilling with a steerable motor. Run in the BHA as a 9-ft length, 1,000-lb sub (on 63_4-in. pipe) the tool uses an internal rotor device powered by mud to "gently" oscillate the BHA to improve weight transfer and reduce friction.

As well profiles become more tortuous and limitations of extended reach boundaries are explored, the tool provides a simple means of expanding the operating window of conventional steerable motor assemblies. Smooth weight transfer and tool face control is possible with PDC bits. Extended intervals can be achieved; and lack of the requirement to work the BHA to obtain / maintain tool face provides significant ROP improvement.

Andergauge will be happy to explain the tool and its advantages. A number in Aberdeen is: 44 1224 780 500; in Houston: 1 281 320 2391.