Enbridge books Allseas’ Solitaire for multiple deepwater Keathley Canyon pipeline jobs

Allseas says that it will install new deepwater crude oil and natural gas export pipeline systems in the central US Gulf for Enbridge Offshore Facilities.

The DP construction vessel Solitaire will handle the campaign, using its modified double-joint `factory’ (DJF).

Enbridge’s contract covers transport and installation of four export pipelines, with a total length of over 515 km, which will take oil and gas from various upcoming deepwater developments in the region to existing offshore hubs, for onward export to market.

The T&I work scope comprises:

•    321 km of 24-in. and 26-in. oil pipelines originating in the deepwater Keathley Canyon area to the Green Canyon 19 (GC19) platform.

•    195 km of 12-in. gas pipeline originating in the same province and connecting to Enbridge’s Magnolia Gas Gathering System, feeding its Garden Banks network.

The new pipelines will each incorporate a 3-km steel catenary riser linking to floating production units. The pipelines, in water depths of up to 2,000 m, will feature multiple crossings, inline structures and termination assemblies to accommodate later tie-ins from nearby discoveries.

Enbridge’s new oil export system will connect to the Rome pipeline (onboard the GC19 platform) which Allseas is due to lay in 2028. The new gas pipeline will connect to the Magnolia system via the new Sparta gas pipeline, owned by the joint venture between Enbridge’ and Shell Pipeline Company, and which Allseas is due to install next year.

Solitaire’s modified DJF, designed for faster S-lay production, features fully automated welding and inspection systems. According to Allseas, this enables more precise, consistent and efficient pipelay in deepwater conditions.

The DJF is also designed to integrate more sophisticated pipe handling, tracking, welding and inspection processes to optimise production flow and deliver highest weld quality standards, the company adds.