West Coast tug technology
2000 is proving to be a busy, innovative year for North American Pacific region tug builders and operators
By Peter Hurme
West Coast shipyards, tugboat operators and equipment suppliers are continuing with newer trends in vessel technology, and in some cases, innovating upon them. So far in 2000, several West Coast tugboats have either been delivered or are pending.
ATB technology comes to Tacoma yard
One shipyard can claim to be the first on the Coast to have recently constructed an ever-rising breed of specialty tugboat. Although the contract was for East Coast deployment, Martinac Shipyard, Tacoma, Wash., was selected to build the 124-foot, 7,000-horsepower MV S-R Everett; the roughly 950-ton (lightship) tug half of an Articulated Tug-Barge (ATB) unit for the Mobil Oil Corp. The tug left the Pacific Northwest at the end of April for a 30-day transit via the Panama Canal to its home base in New York. The awaiting barge half of the contract was constructed by the Bay Shipyard in Sturgeon Bay, Wisconsin.
To date, there is a total of 18 ATBs utilizing the Intercon system that are either operating or in progress, with East Coast operator Bouchard Transportation having just ordered its fourth ATB.
The mechanical lynchpin to making the typical ATB unit work is provided by a special coupler system. In 1983, Kansas City-based Intercontinental Engineering-Manufacturing Corp. (Intercon) went into full-scale development of a tug-barge coupler system that could potentially push continuously and safely.
Intercon's ATB technology is not to be confused with the more basic Integrated Tug Barge (ITB) technology. An appropriate authority on the difference between the two is provided by the U.S. Coast Guard which stated way back in 1981 (NAVIC 2-81) that "pushing mode ITB tugs, in general, are not equipped or capable of separating from the barge and towing on a hawser.... The dual mode ITB tug [the Intercon ATB approach] can separate safely from the barge and shift to the hawser towing configuration at designated sea states."
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