Six Years of Integrity: Large-Scale Offshore Well Suspension and Reactivation

The wells were circulated to inhibited seawater via the Annulus through a recovered GLV and equipped with two plugs set inside the production tubing: 

• A deep-set plug fitted with a Retrievable Junk Catcher Add-on (RJCA)
• A shallow-set plug installed as the secondary barrier. 

These interventions were part of a substantial platform upgrade; the suspended wells were plugged and planned for future production once new facilities were installed. 

The campaign represented one of the largest well suspension operations ever executed in the region, requiring a level of planning, coordination, and execution rarely seen in the industry. The project scope represented a multiyear commitment, with more than 200 interventions completed across the offshore asset.

Interwell delivered a tailored solution utilising its ME, HEX, and HPHT plug portfolio. A total of 122 plugs were custom-manufactured to meet the specific requirements of the campaign. 

Dual barriers were established in each well using these plugs, all deployed with Electronic Setting Tools (EST), enabling download of the setting log and validation of the setting signatures.

To optimise operational efficiency, the Retrievable Junk Catcher Add-on (RJCA) was deployed in combination with all deep-set plugs as a one-run solution, eliminating the need for a separate junk catcher run. This integration significantly reduced both time and cost. 

Throughout the suspension period, Interwell gauges were used to monitor downhole conditions, ensuring well integrity was maintained. Upon reactivation during the unsuspension campaign, the planned recovery of 81 out of 122 installed plugs was completed ahead of schedule, while the remaining plugs continue to ensure overall well integrity, confirming the reliability and effectiveness of the suspension strategy. 

The suspension period extended over six years, during which all wells remained safely secured and under continuous surveillance, demonstrating the robustness of Interwell’s solution in one of the region’s most ambitious offshore campaigns.

All plug installations were successfully confirmed via Electronic Setting Tool (EST) signatures and further validated through pressure testing, ensuring the mechanical integrity of each barrier. All plugs retrieved during the first unsuspension campaign demonstrated the robustness and reliability of the solution. 

The Retrievable Junk Catcher Add-on (RJCA) was deployed in combination with the plug as a one-run solution, eliminating the need for a separate junk catcher run. This approach significantly reduced rig time and operational complexity. 

All equipment was deployed via slickline, offering a cost-effective and efficient intervention method. Mobilisation of Interwell’s integrated tool house further reduced transportation costs and simplified logistics, contributing to overall project efficiency. 

The solution enabled safe long-term suspension and subsequent reactivation of wells, supporting the broader redevelopment strategy with minimal disruption and optimised resource utilisation.