FLNG Hilli Episeyo/Source: CoreMarine

On 13 April 2026, Jumbo Offshore (a subsidiary of the Jumbo Group) and CoreMarine were awarded a contract to transport and install a Soft Soft Yoke (SSY) mooring system and connect two Floating Liquefied Natural Gas (FLNG) vessels in the Gulf of San Matías, Argentina.

The contract was awarded by Southern Energy SA (SESA).

Ben Fitzgerald, Chief Executive Officer of CoreMarine, commented: “Projects of this nature rank among the most complex in offshore construction. Moving, positioning and permanently installing floating assets at this scale requires absolute precision, extensive experience and flawless offshore execution. This is where CoreMarine and Jumbo Offshore truly deliver value.”

The project is being developed by Argentina’s state-owned oil company YPF, Italian energy major Eni, and XRG, with Southern Energy SA (SESA) serving as the operator.

Jumbo Offshore: Responsible for the transportation and heavy lifting of the Soft Soft Yoke (SSY) mooring system using its heavy-lift vessels, as well as the execution of pile installation works.

CoreMarine: Acting as the principal contractor, responsible for complex engineering design, diving operations, subsea construction, flexible pipe installation, system pre-commissioning, and the final connection of FLNG units.

Related works commenced in January 2026, with the actual unit installation scheduled for 2027 and 2028.

The project aims to transport natural gas from Argentina’s Vaca Muerta shale gas field to an Atlantic export terminal. The gas originates from the Vaca Muerta field in Neuquén Province. The San Matias Pipeline starts at the Allen compressor station in Río Negro Province, where Baker Hughes has been approved to supply critical compression equipment, as referenced in previous articles.

The pipeline stretches approximately 473 kilometres with a designed transmission capacity of 28 million cubic metres per day. It has a diameter of 48 inches (1219 mm), a mainstream large-diameter specification for large onshore natural gas trunk lines internationally.

The pipeline uses high-strength carbon steel pipes of API 5L X80 or X70 grade, which can withstand extremely high internal pressures (typically between 90–120 bar) and represent the standard specification for long-distance shale gas transmission.

The pipeline terminates in the Gulf of San Matías, Río Negro Province, approximately 35 kilometres south of the coastal community of Las Grutas.

SESA has not yet publicly announced the final steel pipe procurement contract.

As CoreMarine and Jumbo Offshore are responsible for the “offshore connection” scope, the critical components are not onshore steel pipes but flexible risers paired with the Soft Soft Yoke (SSY) mooring system, which link the subsea pipeline end to the FLNG units.

These pipelines must possess exceptional fatigue resistance and flexibility to accommodate the 360-degree rotation and wave-induced motions of FLNG hulls at sea. They typically adopt a multi-layer composite structure with internal diameters matched to FLNG receiving capacity (approximately 12–16 inches in segmented sections) and are supplied by NOV (National Oilwell Varco).

FLNG Hilli Episeyo (First Unit): Not a newly built facility, this unit is being redeployed from offshore Cameroon. It is expected to arrive in Argentina and commence operations in 2027.

FLNG MKII (Second Unit): Currently undergoing conversion at the CIMC Raffles shipyard in Yantai, China. Converted from the LNG carrier Fuji LNG, the vessel has an overall length of 390 metres and is scheduled to enter commercial operation by the end of 2028.

As a professional enterprise specialising in the supply of flanges, pipes and pipe fittings, GMpiping understands that every connection point is critical in such complex offshore FLNG projects. The Soft Soft Yoke (SSY) mooring system and flexible risers in the Gulf of San Matías ultimately rely on high-performance flanges and fittings to achieve reliable connections with subsea pipelines and FLNG units.

These connecting components must withstand fatigue loads, pressure fluctuations and 360-degree rotational movements in extreme marine environments, while ensuring long-term sealing performance and corrosion resistance.

GMpiping expects that BANGUO, our AI-powered system, will provide Southern Energy SA (SESA), CoreMarine, Jumbo Offshore and other partners with internationally compliant flange and pipe fitting solutions. We look forward to supporting the smooth installation and long-term stable operation of this landmark project between 2027 and 2028, contributing robust pipeline connection solutions to the global energy transition.