Liza 2

One Team Approach to Solve Unity Design Challenge

October 2019

The lessons learned and takeaways from the Liza Phase 1 project have allowed the Liza Phase 2 project to have an accelerated engineering and fabrication schedule. But Phase 2 does have some different characteristics than its predecessor. The project team has to stay alert for potential new challenges and be flexible in developing new solutions.

A significant design difference between the two projects is that the Liza Destiny FPSO has umbilicals mounted on the side, whereas Liza Unity has them mounted on the bow, where vessel motions are greater. Umbilicals are responsible for transporting instrumentation power, controls and fiber optic data, hydraulics, and chemicals from the FPSO’s topsides to the seafloor, and are a key project interface between the three major project EPCs.

TechnipFMC, the subsea and umbilicals EPC contractor, informed the project team earlier this year about an issue with the bow-mounted configuration. The required umbilical support structure would create an over-bending scenario for the umbilicals and exceed the required design criteria for in-service conditions. This over-bending would subject the umbilicals to over-utilization, causing damage and possible early failure.

This issue affected all EPCs. The project team needed to quickly find a solution to keep engineering and hull fabrication moving.

At a dedicated Interface Workshop held in the Netherlands in June, all parties came together to share and discuss potential solutions. Many ideas were discarded due to one limitation or another, but eventually, a workable solution was identified.

This solution required action on the part of all parties. TechnipFMC needed to modify pull-in spool dimensions and shape. SBM, the FPSO contractor, had to change the umbilical balcony design to accommodate the different pull-in spool. Saipem, the installation contractor, had to re-run their installation analysis based on the new configuration.

Initially, the EPC teams conversed in weekly interface meeting calls. However, the teams had only an arms’-distance working relationship with one another. To solve the umbilical over-bending issue, the teams needed to establish trust to allow solutions to effectively be worked in parallel as a team effort.

Over the following months, resulting analyses required further modifications and efforts from all parties to resolve the over-bending challenge. But by working as One Team to resolve these issues as they arose, the project now has a robust design that is suitable for installation pull-in and long term operation—without jeopardizing the overall project schedule.

This collaboration will continue to benefit the project as work continues. Working through this dilemma fostered a deeper relationship among all parties working on this project. Addressing follow-up issues will be significantly easier. Going forward, this experience will continue to pay dividends as the EPCs approach problems as One Team in the pursuit of best-for-project outcomes.