Challenging environments such as unstable clay formations represent high operational risk when running tubulars after drilling is completed. Use of steerable-drilling-liner (SDL) systems combines drilling and casing of the hole, thereby mitigating the risk of not being able to run the liner because of time-dependent formation collapse. This case study presents the difficulties encountered with conventional approaches with a semisubmersible rig in the North Sea during 7-in.-liner-running operations in an unstable clay formation and details a subsequent SDL operation.
Introduction
Midgard, a subsea field, is part of the Åsgard Licence and is located in the North Sea. Midgard consists of three templates with four slots each.
×
Continue Reading with SPE Membership
SPE Members: Please sign in at the top of the page for access to this member-exclusive content. If you are not a member and you find JPT content valuable, we encourage you to become a part of the SPE member community to gain full access.