Crowley Maritime’s ocean-class tugs and high-deck-strength barges have delivered equipment for a deepwater oil rig located 280 miles south of New Orleans, Louisiana, in the Gulf of Mexico.

The equipment, including topsides, tendons and piles, are part of a semi-submersible floating production facility Jack/St Malo, which used the Crowley tugs’ positioning capabilities.

Crowley’s 455 series high-deck-strength barges accompanied the tugs and carried much of the equipment as it was towed offshore.

The facility was successfully moored and made storm-safe at a depth of 7,000ft between the Jack and St Malo offshore oil and natural gas fields by Crowley’s Houston-based Solutions project management team.

The delivery was completed in three stages of work in both nearshore and offshore waters.

In the initial nearshore phase, the topsides were skidded onto the company’s 455 series barge Julie B at the Keiwit facility dock in Ingleside, Texas, in Corpus Christi, where they were later lifted and installed onto the hull of the facility.

The Ocean Wind and Ocean Wave dynamic positioning 1 tugboats pushed the Jack/St Malo facility away from Corpus Christi, through the Port of Aransas, Texas, and out to deeper waters, while the Ocean Sun was equipped to assist, if required.

"The delivery was completed in three stages of work in both nearshore and offshore waters."

The second phase of work, the offshore stage, began with relocation to deeper waters, where the Ocean Wind and Ocean Sun towed the facility to its final location, alongside the tugboat Harvey War Horse II, contracted by the company.

During this phase, the Solutions team arranged for the company’s 455 series barge 455 7, towed by tug Warrior, and third-party barge Marmac 400, towed by tug Pilot, to deliver the piles, or long pipe-like structures that serve as anchors for the platform, to the project site.

Finally, Pilot towed the Marty J, which made three subsequent trips to the installation site to deliver additional equipment including chains, connectors and line reels that were used in the mooring of the floating facility.

In the final positioning phase, the Ocean Wind, Ocean Wave, Ocean Sky, Ocean Sun and Harvey War Horse II worked together to hold the Jack/St Malo in its final location and provided support as the spar was connected to its moorings and made storm-safe.

Crowley solutions vice-president John Ara said: "Not only was the project completed safely and on time, but it also helps to illustrate the increasing competence and capability of our crew and vessels."

The first two ocean-class vessels, Ocean Wave and Ocean Wind, have an overall length of 146ft, beam of 46ft, hull depth of 25ft and design draft of 21ft.

Ocean Sky and Ocean Sun, the second two tugs of the class, are classed as DP2 and are 10ft longer.

Expected to begin oil and natural gas production later in 2014, the facility will have a capacity of 170,000bpd and 42.5 million standard cubic feet per day of natural gas.