TSMarine's Perth subsidiary operates a multi year service contract with Woodside Energy Ltd and this milestone project has seen TSMarine's offshore well intervention vessel, the Havila Harmony successfully deploy, install and test seven subsea trees and carry out wireline intervention on all seven wells. This is the first phase of a 2008 campaign which will include the installation and completion of up to 11 subsea trees in the Vincent field and a range of commissioning and decommissioning projects.
The project marked a number of other milestones. This was the first time the deployment and installation on wire of subsea xmas tress from a monohull vessel has taken place in the region. Similarly, it was the first time a subsea well intervention project has been carried out using wireline services from a monohull vessel in Australian waters.
The intervention was completed in partnership with WellOps South East Asia and Schlumberger, both of which were integral to the success of the operation.
Alasdair Cowie, CEO of TSMarine explained: "The world record water depth for subsea wireline intervention from a monohull vessel is 377 meters. In our first ever subsea well intervention project we operated in a water depth of 372 meters, a significant achievement within this hugely successful project."
John Edwards Regional Director of TSMarine's Asia Pacific operations added: "The success of this project is a culmination of over two years of planning and engineering, working closely with our customer Woodside Energy and our primary subcontractors. Achieving wireline runs with significant success rates, and reaching downhole well depths of 1450 meters from the Harmony is an extremely pleasing result and is of fundamental importance for the future of our contract with Woodside Energy.
"In addition to the operational success, we completed the project with an outstanding HSE performance record. It shows that proper planning and preparation will deliver great business and safety outcomes. The two go hand in hand."
The project was completed in four stages - detailed engineering, mobilization, subsea tree deployment, and wireline well intervention. Conventionally xmas tress would be run from a drilling rig using rigid riser and a hydraulic umbilical to supply locking and testing capability.
From the Havila Harmony, the trees were run using the vessels 150 tonne active heave compensated crane and a simple mechanical running tool. Locking and testing was supplied by the vessels ROV systems, which were fitted with a specially developed hydraulic power and tooling pack. Hanger and deep-set plugs were removed by slick line intervention using Wellops subsea lubricator (SID) and Schlumberger Wireline Services.
The Havila Harmony is on long-term charter to TSMarine and was delivered in March 2007.
She is configured to undertake subsea decommissioning; rigless well intervention services, and subsea construction support activities and has a comprehensive safety case accepted by NOPSA, Australia's National Offshore Petroleum Safety Authority, covering these and more activities.
Built to the new and demanding "Clean Comfort V" Norwegian standards, the ship conforms to the highest level of environmental class conditions required of vessels of this type in the offshore industry sector.
Following a recent £53 million investment, TSMarine expects to grow its own fleet of subsea decommissioning and rigless intervention vessels to five by late 2009, taking earnings to more than £100million.