This industry case study from Expro highlights how its ReLine HYD expandable casing system helped Ithaca restore well integrity on the Captain platform offshore UK, enabling sidetrack drilling while reducing operational complexity and rig time.
Expro addresses casing integrity challenges on Ithaca’s Captain Platform
Expro has detailed a casing repair operation carried out for Ithaca on the Captain platform offshore UK, where corrosion in a 13⅜-inch casing section caused a leak and raised well integrity concerns.
The damage threatened the planned drilling programme. A conventional repair approach would have required cutting and retrieving the compromised casing, drilling a new 17½-inch hole section, and running and cementing replacement 13⅜-inch casing. This would have added operational complexity, rig time and cost.
According to Expro, the operator required a permanent repair solution capable of restoring casing integrity across an extended corroded interval while minimising operational risk and disruption.
ReLine HYD system used for expandable casing repair
Following an assessment of the available well data, Expro developed a tailored repair programme using its ReLine HYD expandable casing system. The solution involved installing a 500-foot expandable casing patch to clad the damaged section and provide a long-term integrity barrier.
The operation also included pressure testing the 13⅜-inch casing sections that would remain uncovered by the patch, following the cutting and retrieval of the 9⅝-inch casing. Expro used the AEON RTP and an abandonment valve as part of the integrity verification process.
The casing patch was deployed using Expro’s tubular running services (TRS), with the installation completed in a single run. Subsequent pressure testing confirmed that casing integrity had been restored.
Expro also highlighted collaboration across its product lines as a key factor in coordinating the operation and reducing execution risks.
Casing repair enables Ithaca to progress sidetrack operations
The repair eliminated the leak and restored wellbore integrity, allowing Ithaca to proceed with its planned activities. These included setting a cement plug below the repaired interval and advancing sidetrack drilling.
The intervention helped the operator avoid the extended delays and additional expenditure associated with a more extensive casing replacement programme. It also preserved the opportunity to develop the well further.
Without the repair, Ithaca could have faced prolonged operational disruption and the potential loss of the planned sidetrack opportunity.
Expandable casing technology supports offshore well integrity
The project illustrates the application of expandable casing technology to address corrosion-related well integrity challenges in an offshore environment.
As described in Expro’s case study, the intervention combined a targeted casing repair with integrated service delivery to restore well integrity and enable further drilling operations. The outcome highlights how specialist well intervention technologies can help operators manage casing damage, limit operational disruption and preserve future well value.
