In 2017 Jumbo Offshore executed the first phase of the Hilli Episeyo project for Golar LNG in Cameroon. This phase involved the transportation and installation of a soft yoke anchor system.

Jumbo installs first FLNG in Africa
Images courtesy of Jumbo Offshore

The subsequent phase of hooking-up Golar’s first dedicated floating liquefied natural gas (FLNG) unit to the subsea anchor system, umbilical and gas riser has now also been successfully completed in the Kribi field. Throughout this project emphasis was given to safety and operational excellence as well as keeping the project within budget.

Jumbo Project Management

Immediately after the mooring system installation, the Jumbo team’s attention was shifted towards the second part of the project with a focus on:

  • Project management & engineering
  • Subcontractor management
  • Charter of diving support vessel
  • Managing client expectations
  • Diving Support Vessel
     

Golar was set to subcontract the towing spread of the Hilli Episeyo as well as the station keeping spread (tugs to keep the Hilli in position). The base requirements for the Hook-up phase was to charter a Dive Support Vessel (DSV) capable of accommodating all project crew, able to work in DP2 mode and stay in position on a 4-point-mooring system. The latter was required to allow divers to step off further from the DSV.

The result of the market scan was a hybrid solution, consisting of a small DSV (mulitcat-type vessel) and an accommodation barge for the different shifts working on the DSV. The pictures show the DSV Roxane Z working close to Hilli Episeyo.

Soft Yoke Hook-up

The hook-up of the Soft Yoke was carried out with the help of lift bags. Large bags were connected to the center tank and inflated by divers. This reduced the weight of the yoke. With the small winches on the Hilli Episeyo, Jumbo crew were able to connect the chains to the dedicated slots on the bow of the Hilli.

Jumbo Tow Masters used the station keeping tugs (4-off) to keep the Hilli Episeyo in position. The tugs were connected to the Hilli Episeyo after which she was pulled in position slowly. Several attempts had to be made to install the chains as the current at the location gave difficulties in station keeping.

In the early morning of 01 December the hook-up of the chains was completed. The riser and umbilical were finally connected late in the afternoon on 02 December.

Jumbo demobilized the spread in Douala on the 04 December 2017.

Tim Klieverik: Project Manager Jumbo says “Jumbo has done a tremendous job to install the Hilli Episeyo on the pre-installed anchoring system. We showed we can keep control in difficult situations and stick to the pre-defined plans. This could only be achieved with thanks to the team spirit and excellent efforts of the Jumbo and Golar LNG team and our subcontractors, in the preparation phase as well as during the offshore execution. ”

Source: Jumbo Offshore