These vessels comprise a fleet of three AT/B’s operated by Keystone Shipping of Philadelphia, on behalf of BP Amoco. Two of the units are specially fitted with heaters and nitrogen inerting systems for the carriage of Paraxylene between the Gulf and East Coasts, in what is essentially a liner service. The third unit carries clean products from Texas City to Tampa.


Before conversion to the INTERCON system, these units averaged between 25 and 40% weatherbound. Average speeds were under 7 knots. After conversion, the units went to 100% availability and less than 1% weatherbound time. Speed increased on average, over 3 knots, while fuel consumption fell. The units went from losing money to becoming profit centers.

OT&BE designed the entire modification of the tug and the barge, including stability, structural design and analysis/FEA for both the tug and barge, loadbox design, connection force prediction, and notch design. The conversions took place in 1997-1999, and all three units are still in service today. The work on both the tug and the barge was accomplished in record time by Gulf Marine Repair of Tampa, FL. What was outstanding was the quality level of the work, despite the speed with which it was accomplished.