Subsea 7 boosts reel-lay vessel fleet

Feb. 1, 2021
Subsea 7 has taken delivery of the newbuild reel-lay vessel Seven Vega.


Subsea 7 has taken delivery of the newbuild reel-lay vessel Seven Vega.

According to Phil Simons, executive vice president Projects & Operations, the new vessel has been designed to install economic flowline technologies that address the growing trend toward longer subsea tiebacks. These include complex pipe-in-pipe, piggyback and electrically heat-traced flowline systems, risers, umbilicals, and structures in water depths up to 3,000 m (9,842 ft).

Built by Royal IHC, the Seven Vega has an overall length of 149 m (489 ft), a breadth of 33 m (108 ft), and a DP-3 system. Its reel-lay system has a 600-ton top tension capacity consisting of a 32-m (105-ft) main reel and a 17-m (56-ft) auxiliary reel with a maximum storage capacity of 5,600 tons and 1,600 tons, respectively. It is fitted with cranes offering a lifting capacity of 250 tons and 50 tons, and multiple smaller cranes alongside two side-launching work-class ROV systems.

The vessel should be operating on BP’s Manuel project in the US Gulf of Mexico, a two-well subsea tieback to the Na Kika platform, in water depths of up to 1,900 m (6,233 ft).

Oceaneering secures GoM assignments

OneSubsea, a Schlumberger company, has contracted Oceaneering International to supply the first-ever 20,000 psi-rated subsea hydraulic junction plates and associated connection hardware for Chevron’s Anchor field development in the deepwater Gulf of Mexico.

The company will oversee the design, engineering, and production of the hydraulic connection hardware along with integrated flying lead assemblies and installation equipment.

Anchor is the first 20,000 psi-rated field to be developed in the Gulf.

Sebastian Hennings, Plant Supply Chain Manager, OneSubsea, said: “The Chevron Anchor project – awarded under the 20-year subsea master services agreement for the Gulf of Mexico – is industry’s first fully integrated subsea production system rated up to 20,000 psi.”

Nuno Sousa, VP, Manufactured Products, Energy, at Oceaneering, added: “This 20,000 psi-rated subsea hydraulic connection hardware solves one of the industry’s biggest challenges in developing high-pressure fields and allows operators to explore deeper depths more safely. The new design provides a highly-reliable and robust solution based on our field-proven M Series junction plates of which there are more than 6,000 in operation globally.”

The plates meet API 17F and have been thoroughly tested to meet all project and field requirements, according to the company.

The Anchor field is in the Green Canyon area about 225 km (140 mi) offshore Louisiana, in water depths of about 1,524 m (5,000 ft). Stage 1 of the Anchor development consists of a seven-well subsea development and semisubmersible floating production unit. First oil is expected in 2024.

TechnipFMC has contracted the company to provide 2-in. M5 connectors and chemical throttle valves (CTV) for Murphy’s Khaleesi/Mormont and Samurai subsea tiebacks in the US GoM.

The M5 connector is said to provide an easy-to-install, fly-to-place connection solution that enables injection of gas or chemicals into subsea infrastructure. It also serves as an access point for future subsea field intervention activities such as gas lift, chemical injection, well stimulation, hydrate remediation, flooding and venting operations, acid injection and scale squeeze.

Oceaneering Rotator CTVs regulate the flow of chemicals—such as scale, wax, and corrosion inhibitors—delivered to subsea production systems. Their functions are diverse, from flow control to metering and highly accurate dosing. CTVs are said to eliminate the need for topsides injection and dedicated umbilical lines.

The Samurai and Khaleesi/ Mormont fields will be tied back to the King’s Quay FPS in the Green Canyon area. First oil is expected in 1H 2022.

DeepStar lets subsea systems engineering contract

Ocean Power Technologies Inc. (OPT) has received a DeepStar project award to study the deployment and operational requirements of using its PB3 PowerBuoy to provide remotely controllable zero carbon power for deepwater subsea oil production applications.

“Remote Zero Carbon Power for Electric Subsea Operations” is a techno-economic feasibility study funded by the DeepStar CORE program and supported by project champion Total E&P Research and Technology USA.

The project will explore using OPT’s PB3 PowerBuoy and a subsea battery to reduce the cost and carbon emissions associated with conventional means of powering and controlling subsea oil and gas production equipment. The study will consider water depths of 1,000, 2,000, and 3,000 m (3,281, 6,562, and 9,842 ft).

Daniel Byrd, Subsea & Deepwater Manager at Total E&P Research and Technology USA, said: “Total is interested in studying how locally generated electrical power can support its vision of all-electric, low-carbon developments in deep offshore. This study is intended to identify which combinations of parameters (water depth, tieback distance) could bring cost savings for a simple subsea architecture using OPT’s PB3 PowerBuoy.”

DeepStar is a joint industry technology development program focused on advancing technologies to meet its members’ needs. Along with Total, members of the Texas-based consortium include Chevron, CNOOC, Equinor, ExxonMobil, JX Nippon, Occidental, Petrobras, Shell, and Woodside.