Designing Wells on a Lifecycle Basis: A Case Study from the Statfjord Field

Abstract

To achieve the goals of maximum lifecycle value of wells in the Stafjord field, continuous improvements in well design, completion and well intervention techniques have been made over the past 10 years, A major challenge has been to simultaneously optimise reservoir penetration, drilling and completion operations and later well interventions, This paper will review the development in the well design and completion techniques from the low angle « 60°) wells with cemented liner and step down nipple profile completion to the horizontal and extended reach wells with monobore completions, This includes the lessons learned from the numerous workovers performed and how they lead to a change in completion design to ensure reliability, redundancy and optimised production. The impact of the well profile and how it should be optimised for future light interventions, i.e. coiled tubing, or wireline tractor will also be discussed.Finally, the advantages of working in multi-disciplinary teams from the early planning stage to completing the well will be addressed.