Tamboritha Complete Construction Support For Apache at Coniston
3 September 2013
Tamboritha were contracted by Apache Energy Ltd to provide a support vessel with two work-class ROVs and a positioning spread to assist with the commissioning of the Coniston/Novara installation project during July and August 2013. The work scope also included changing out two subsea control manifold pods and performing subsea observations and inspections associated with the restart of the Van Gogh field.
To carry out the work, Tamboritha mobilised the 79.7m DP2 vessel GO Explorer from Singapore to Dampier, Western Australia where the project personnel joined the vessel and the equipment was installed. During the mobilisation at Dampier Port, Tamboritha’s recently upgraded Super Scorpio Workclass ROV and Cougar XT Light-Workclass ROV, an EGS positioning system and client-supplied control pods and tooling were installed onto the vessel prior to the vessel sailing out to the work site.
The environmental aspect for this project was a primary concern, as the Coniston/Novara fields are in water depths of 360-380m and approximately 45km from the Ningaloo Reef World Heritage Site. Tamboritha’s policy of using environmentally-friendly hydraulic oils in all ROV systems and tooling was a factor in securing the contract, and although no leak occurred, the use of these vegetable-based oils ensured that any risk of contamination of this pristine reef was kept to a minimum.
During the project, the ROV and vessel spread assisted the construction vessel (CSV) to complete the commissioning of the Coniston/Novara fields as part of the Ningaloo Vision Upgrade Project. During this support phase, the ROVs carried out valve actuations and monitoring of operations whilst valves were actuated from the CSV and the FPSO.
The control pod change-out procedure at Van Gogh was carried out using the ship’s 25T heave-compensated subsea crane to launch and recover the running tool and a client-supplied hot stab was installed onto Tamboritha’s Super Scorpio ROV to actuate the running tool. The ROV spread then assisted the Ningaloo Vision FPSO personnel by actuating and also monitoring valve actuations during the start-up process whilst restarting the FPSO.
The vessel was demobilised in Dampier after the successful completion of the project.