Washburn & Doughty deliver ATB tug to Moran
In September, Washburn & Doughty Associates , East Boothbay, Maine, delivered the 121′ × 36′ × 18′ Mary Ann Moran to Moran Towing Corp., New Canaan, Conn.
The tug is the fourth in a series of 121′, 5,100-hp ATB sister tugs whose construction began in 2006, said the boatyard’s Bruce Washburn. The first three were the Pati R. Moran , Linda Moran , and Lois Ann L. Moran . Ocean Tug & Barge Engineering , Milford, Mass, designed the ATBs.
The first three are working on the East Coast and mated with petroleum barges. The Mary Ann Moran is operating out of the New Orleans area, pushing a grain barge to Puerto Rico. The grain barge was converted to ATB use, though all the barges have similar notches so they are interchangeable.
The Mary Ann Moran is connected to its 400′ grain barge by an INTERCON C series coupler with 34″ rams.
About the only difference between the four tugs is that the first two were outfitted with pairs of 12-cylinder EMD 645-series diesels. The Lois Ann and the Mary Ann each have a pair of the newer Tier 2 EMD 12-71OG7C-T2s. Each engine is rated at 2,550 hp.
“They adjusted the ratings on the 710s because they wanted all the engines matched up,” Washburn said.
The EMDs spin 5-bladed, 115″ Rolls-Royce New Generation Workwheels on 10″ shafts through Lufkin RHS2500HG marine gears with 4:1 ratios.
Electrical power is supplied by a pair of 125-kw Marathon gensets, which are connected to John Deere 1,800-rpm engines.
To meet SOLAS requirements, there’s a keel-cooled 65-kw Marathon emergency generator above the main deck. If the two larger gensets lose power, then an Industrial Power Systems emergency switchboard detects the power loss and automatically starts up the emergency genset.
On the after deck is a Markey CEWP-90, 40-hp electric capstan with a rated line pull of 60,000 lbs. Up forward is a Markey CEW-60, 15-hp electric capstan with a rated pull of 30,000 lbs.
This is the first ATB superstructure tower built at Washburn & Doughty. Because of space limitations, the other three were built next door at Hodgdon Yachts . “With the new building, we have the capability to build them. It allows us to put on one more level,” noted Washburn.
Washburn & Doughty’s latest ATB is classed A1 towing service and AMS, with an international load line. It complies with SOLAS regulations. “Basically it’s set up to go anywhere,” Washburn said.