Allseas’ construction vessel Pioneering Spirit has completed the infield pipelay scope for BP’s ultra-deepwater Greater Tortue Ahmeyim (GTA) liquified natural gas project offshore Mauritania and Senegal.
Two months after arriving in the field, production crew welded, scanned and field joint coated the final piece of pipe for the second 16-inch export gas line.
Safely landed in a 2-metre target box at 2400-meter water depth, the pipeline will be recovered in J-mode configuration to install the termination assembly.
To make this happen, the vessel aft has been fitted with a bespoke J-mode frame with a 1000-tonne load capacity, which was designed, built and installed on board in only eight weeks by Allseas’ engineering and fabrication teams.
The pipelay scope comprises approximately 75 km of 16-inch export lines and 10 km of 10-inch CRA infield lines, some of the pipeline infrastructure exceeding 2700 meters water depth at the deep end.
The main firing line and double jointing facilities on Pioneering Spirit have run in parallel throughout the campaign. Pioneering Spirit will conclude the offshore works by installing the six outstanding flowline termination assemblies.
“Our Agile approach was key to a quick and efficient start to the project and decision-making process throughout the offshore campaign. Thanks to great collaboration between the onshore and offshore teams, we’ve overcome all challenges faced during the project preparation and execution phases and met all milestones without delay,” said Laurent Beghin, Allseas Project Manager.
Kosmos Energy discovered the GTA field in 2015, with BP signing onto the project through an agreement with Kosmos in 2016 as project operator.
The project’s first phase is set to produce around 2.3 million metric tons of LNG per year. GTA comprises both FPSO and FLNG facilities.
The FPSO will process natural gas and export it by pipeline to the project’s FLNG facilities, 10 km offshore. With eight processing and production modules, the FPSO will process around 500 million standard cubic feet of gas per day.