Pioneering vessel-based installation of Xmas trees
Innovative approach to Xmas tree installation leads to multi-million dollar savings.
Maersk Supply Service was contracted to install all ‘Xmas trees’ at ExxonMobil’s Erha development project off the coast of Nigeria in 2005, including installing all the subsea Xmas trees in depths of up to 1600m. With two moored semisubmersible rigs drilling and more than 30 Xmas trees to be installed, each weighing up to 45 tonnes, this project presented unique challenges.
At the time, normal procedure was to install Xmas trees from a rig. In this project, however, Maersk Supply Service devised a solution that would allow installation by vessels – something that had not been done before.
The solution involved fitting an AHTS vessel with a subsea crane. The active heave-compensated crane enabled faster installation using the crane wire, rather than using a rig drillstring. This not only saved very valuable rig time, but also allowed for greater flexibility in the deployment of the Xmas trees.
Due to the outstanding performance of the vessel and crew as well as careful project planning, the procedure proved highly successful. Installation time was dramatically reduced compared with using a rig, ultimately saving the client an estimated double-digit million US dollar figure.
The vessel also performed other anchor handling and towing duties as required in support of the two moored semisubmersible rigs. The project in Nigeria ultimately led to a successful contract for ExxonMobil in Australia.
More Case Stories
- Perenco Subsea Structure Recovery Servicescommunications2021-05-04T14:25:26+00:00
- Pre-installation of an FPSO mooring systemcommunications2021-03-09T08:17:59+00:00
- Anchor Pre-lay Offshore MexicoHayley Palmer2020-12-11T14:23:25+00:00
- Fluminense Mooring Lines Life ExtensionHayley Palmer2020-05-12T12:40:47+00:00
- Multi-Purpose Field SupportHayley Palmer2020-05-12T12:04:42+00:00
- Offshore Wind Walk-to-WorkHayley Palmer2020-05-12T11:28:24+00:00
- FPSO Mooring Install & ReplacementHayley Palmer2020-08-14T11:12:41+00:00
- Supporting Testing of Upgraded Ocean Cleaning SystemHayley Palmer2020-10-14T09:27:36+00:00
- Angola Light Well Intervention CampaignHayley Palmer2020-08-14T11:13:29+00:00
- Tow & Installation of Ocean Cleaning SystemHayley Palmer2021-05-12T10:31:42+00:00
- Leadon DecommissioningHayley Palmer2019-12-30T11:56:37+00:00
- Angola Block 15 Jumper InstallationHayley Palmer2020-08-14T11:14:37+00:00
- Deep Sea Mineral ExplorationHayley Palmer2019-12-30T12:13:32+00:00
- Culzean FSO Towing & MooringHayley Palmer2019-12-30T15:11:50+00:00
- HebronHayley Palmer2019-12-30T15:21:32+00:00
- Janice & James DecomissioningHayley Palmer2020-10-14T09:26:56+00:00
- Maersk Connector Cable InstallationHayley Palmer2019-12-30T15:38:06+00:00
- Mafumeira SulHayley Palmer2020-08-14T11:17:25+00:00
- LivornoHayley Palmer2019-12-30T15:49:56+00:00
- SchiehallionHayley Palmer2019-12-30T16:16:56+00:00
- Skarv FPSO Tow & Hook UpHayley Palmer2019-12-30T16:21:12+00:00
- GjøaHayley Palmer2019-12-30T16:25:25+00:00
- Peregrino FPSO Hook UpHayley Palmer2019-12-30T16:28:24+00:00
- Angola Installation & TowingHayley Palmer2020-08-14T11:17:49+00:00
- ErhaHayley Palmer2020-08-14T11:35:13+00:00
- CABGOC Offshore SupportHayley Palmer2020-08-14T11:18:08+00:00
- Arctic ProjectsHayley Palmer2020-12-11T14:33:08+00:00