Well Heidrun A-45, located in the Norwegian Sea, was completed in an unconsolidated sandstone reservoir that required sand control. The lower zone was completed with a gravel pack completion and the upper zone was left unperforated. To enable production from the upper zone, the lower zone needed to be abandoned after onset of sand production.
Typically these recompletions are performed with a workover rig, but this option was not possible because of high cost and rig availability. After considering various alternative options, the whole operation was performed rigless with coiled tubing. The job consisted of abandoning the lower zone, perforating the upper zone, and then performing a through-tubing gravel pack on the upper zone.
After the workover operation, the new completed sand control system produced at 500 Sm3 o.e. per day which represents 100% incremental increase in the oil production rate compared to the old sand control system that was plugged and abandoned. This activity featured the largest through-tubing gravel pack operation performed in the area.
This case study provides a background for the planning, execution, and evaluation of the operation, demonstrating a viable alternative for sand control rigless recompletion.