Ekofisk Phase II - 2/4X Drilling Facilities. The Tools & Technologies Are Here: Now What?
Authors: Arnim R.C. , McGill John 
Published: December 2007

Abstract
Ekofisk Phase II involves a new wellhead platform designed for 50 wellslots. A new generation platform rig will be provided for this new facility which will be equipped with the latest available tools and advanced technological systems.
The first part of this paper describes the major advanced rig design features and rig equipment incorporating man machine computer controls for the driller. The integration facilitated by systems like those incorporated into the 2/4X drilling rig puts a big question mark on our traditional methods of planning and organizing within our drilling and contractor's organizations as well as between the specialist contractors involved in the drilling of a well. The real challenge is not just technological implementation but also the planning, organization, supervisory and communication issues required to make effective use of these technologically advanced features. The second part of the paper provides a discussion of the significant cultural departure from the traditional drillfloor approach that must be made to extract the desired performance from such a drilling facility.
The technology is here. The large monetary commitments have been made. Now we need to encourage and, in some cases, to change our organizations in order to apply these technologies in the direction where the real potential for cost savings and safety improvements are buried. The driller's role will have to rapidly evolve. The centralization of information and drilling control which has been provided to the drillfloor will provide the opportunity to maximize the effectiveness of the drill team to the benefit of rig efficiency and safety.

Introduction

Ekofisk Field
The Ekofisk Complex is at a crossroads. Aging facilities, increasing operating costs, uncertainties surrounding subsidence of the seabed, and safety issues raised by the Norwegian Petroleum Directorate (NPD) prompted the Phillips Norway Group to consider future options. New facilities and technologies offer the opportunity to increase hydrocarbon recovery, reduce costs, enhance safety and work environment, reduce environmental impacts and mitigate the impact of subsidence. For these reasons the Phillips Norway Group decided to implement the Ekofisk II plan, which involves building a new infrastructure at Ekofisk center.
The Ekofisk Field (Figure 1 & 2), discovered in 1969, was put on early production in 1971. Since that time seven new fields have been developed within the production license area. Over 1.2 billion barrels (over 200 million m3) of oil, over 5.2 trillion SCF (over 140 billion standard m3) of gas, and more than 100 million barrels (over 15 million m3) of natural gas liquids have been produced from the Ekofisk Field alone. Ekofisk center (Figure 3.) has been in operation for more than 20 years.
But circumstances have changed after 20 plus years of production. Operating costs are increasing relentlessly due to aging facilities and the work necessary to stem declining output. The overburden has subsided reducing the air gap originally designed into the platforms to an unacceptable level. Subsidence is continuing and the need to decommission existing producing platforms will become necessary.
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