Company developed new APN-E/F gas fields in 2011, namely the APNE-A, APNE-B, and APNF. One of the critical scopes of this project was subsea tie-in work, which was the biggest risk to be managed. This tie-in work was a part of the key success milestones that would affect the overall project completion. There were a lot of constraints and concerns that had to be considered during the execution phase of the engineering, fabrication, and installation work. The wet lift method was chosen after a robust selection process from several options e.g. tie-ins using subsea mechanical connectors, the dry lift and wet lift methods. These options were reviewed against the selection criteria of safety, schedule/shutdown time, cost and quality/integrity for the operation. The wet lift tie-in method for the 24" subsea pipeline was finally selected after being thoroughly assessed by the discipline functions.
The implementation of the wet lift method started with the detailed planning of the resources, material, work sequences and timeline schedules. As a result, the work was safely and reliably executed ahead of schedule.