ONWARD goes behind the scenes at VT Halter Marine for a sneak peek at the progress of Q-LNG’s articulated tug and barge unit.

VT Halter Marine has continued to make scheduled progress with the programme to build America’s first offshore LNG articulated tug and barge (ATB) unit for Q-LNG Transport. The contract was awarded to VT Halter Marine by Q-LNG in November 2017, with delivery on track for the first quarter of 2020.

Q-LNG owns and operates assets providing marine transportation of LNG, and has a long-term contract with Shell Trading (U.S.) Company to deliver LNG as a fuel source to various ports in Florida and the Caribbean. Q-LNG is dedicated to extremely safe transits and bunkering of LNG fuel while servicing these ports. In achieving the rigorous standards, Q-LNG has chosen to partner with VT Halter Marine to design, engineer and construct its maiden LNG ATB. Wärtsilä, a Finish manufacturer, was the supplier for the vessel’s cargo-handling, cargo-control and cargo-containment systems.

The LNG ATB unit will meet the requirements of the ABS and the IGC code. It can carry 4,000 cubic meters of LNG, with the barge measuring 324’ x 64’ x 32.6’ and the tug measuring 128’ x 42’ x 21’.

As with any first-of-its-kind vessel, design specifications did not always sync up with the standards set out by the American Bureau of Shipping (ABS), US Coast Guard and International Gas Carrier (IGC). VT Halter Marine and Q-LNG have been working closely over the last 15 months to resolve the design issues and achieve approvals across Class and Flag.

Mr Ron Baczkowski, President and CEO of VT Halter Marine, revealed: “There has been good mutual respect between the team members of VT Halter Marine and Q-LNG and both companies have maintained good communication at the highest levels. The teams have also worked closely with Shell, the ultimate customer, who has supported us well in the resolution of issues across Class and Flag.”

Representatives of Q-LNG, Wärtsilä and VT Halter Marine jointly inspected the LNG Bunker Barge.

Another design challenge faced by the VT Halter Marine Engineering and Production team involved the requirement for a barge that could be “permissively manned”. This meant that the crew from the tug had to be able to access the barge during transits in order to maintain and check the LNG system.

“Our solution was to develop a barge automation system which is monitored and can be controlled on the tug. The automation is both hardwired and wireless – the latter being an added feature in case the tug needs to de-couple from the notch to tow the barge. The Q-LNG ATB unit is also the first ATB vessel to receive a DP-1 notation for Dynamic Positioning. When in the notch, the DP system controls the bow thruster on the barge and the two Z-drives on the tug,” Ron explained.

For now, the proof is in the pudding and the ATB’s final test would be during the sea trials scheduled for the first quarter in 2020. “We’ve built a large number of ATB vessels – all oil or chemical carriers. An LNG ATB adds some complexity in that the condition of the product has to be constantly monitored and controlled. However, the lessons we’ve learned about LNG supply chain and the handling of cryogenic materials have allowed us to move into building LNG bunkering barges to support the increased use of LNG-powered vessels in US ports,” he added.

Mr Shane Guidry [right] with VT Halter Marine’s Mr Robert Socha at the steel cutting for Q-LNG’s ATB.
“Our teaming with VT Halter Marine for America’s first offshore LNG ATB is one of the most important steps in the coming years for LNG. VT Halter Marine’s experience with LNG-powered vessels and the capabilities of its facility for delivering industry-leading ATB units is only the beginning to the success of this and future LNG programmes.”
Mr Shane Guidry
Chairman and Chief Executive Officer, Q-LNG