Shell Offshore Inc. has signed a commercial agreement with HYDRA SUBSEA covering standardized deepwater pipeline installation for short-distance subsea tie-ins in the US Gulf of Mexico. HYDRA SUBSEA announced the deal Oct. 15.

The agreement sets commercial and technical terms under which the companies could advance qualifying projects. Each project remains subject to separate evaluation, approval, and award, HYDRA said in its release. Nothing is sanctioned yet.

What is the first proposed project?

Shell's Appomattox gas lift flowline is the first candidate under the framework. Appomattox sits about 80 miles offshore Louisiana. Shell operates the field with a 79% interest. INEOS holds the remaining 21%.

A gas lift flowline (a line injecting gas into production risers to maintain flow) is a typical short-distance tie-in scope. The proposed work has not received a final award.

Which vessel will do the work?

HYDRA is reactivating its Subsea Legend vessel. The unit is expected to receive:

• New mission equipment
• A 250-ton active heave-compensated subsea crane (a crane that counters wave motion to hold load position)
• A new propulsion system
• An upgraded dynamic positioning system (computer-controlled thrusters that hold station without anchors)

The vessel is intended to support a standardized installation model for 6-in. and 8-in. rigid pipelines.

Why standardize tie-in installation?

"Smaller deepwater developments need an execution model aligned with their scale and economics," said Trevor Davis, chief executive officer of HYDRA SUBSEA.

The agreement gives Shell an additional option for selected projects where a repeatable installation approach can improve predictability, Davis said. He added that the model could be applied elsewhere in the US Gulf of Mexico.

The takeaway: Shell has secured terms, not a contract. The watch item is a final award on the Appomattox gas lift flowline and the timing of Subsea Legend's return to service.