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PHOTO: Jake Jarrell

November 2, 2010

Tug Mary Ann Moran enters service

Now in service with Moran Towing Corporation, the Mary Mary Ann Moran is a 121 ft x 36 ft x 18 ft Intercon Tug designed by Ocean Tug & Barge Engineering Corp. She is the the fourth vessel of this design to be delivered to Moran by shipbuilder Washburn & Doughty Associates, Inc. of East Boothbay, Maine.

“I can say that this boat is by far one of the best vessels I have ever had the pleasure of working on in over 30 years in the industry," says the vessel’s captain, Mr. Jake Jarrell. "I was very impressed with the professionalism and quality of the workforce at Washburn & Doughty and the end result of their product.”

The vessel has been built to ABS classes + A1 Towing Service and +AMS, with an international load line. The vessel complies with all applicable SOLAS regulations.

The Mary Ann Moran admeasures 264 gross tons (U.S. regulatory tonnage) and 689 gross tons (International tonnage). Both U.S. and Panama Canal tonnage certificates were provided.

The tug has an Intercon C series coupler outfitted with 34 inch diameter rams; hydraulic tensioning; port and starboard hydraulic power units; motor control center; logic/control panel; and two touch screen station remote controls.

Her two electronically controlled EMD 12-710G7C-T2 main engines meet Tier 2 emission standards. Each is rated at 2,550 HP at 800 RPM and outfitted with Lufkin model RHS2500HG reverse reduction gears. Nominal gear ratio is 4:1.Mary Ann Moran has ABS grade 2, 10 in steel shafts, and Rolls Royce New Generation Workwheel, 5-blade, 115 in diameter, stainless steel propellers.

EMI supplied the electro-hydraulic steering system, which interfaces with the vessel’s gyrocompass and autopilot.

The electrical system is a 480 V AC, 3-phase, 4-wire system, designed for non-paralleling operation. The two ship service generators are John Deere Tier 2 emissions certified 1800-rpm marine engines with Marathon generators, each providing 125 kW, 480VAC, 3-phase power.

The main switchboard, manufactured by Industrial Power Systems, is located in the engine room and fitted with a 480 V, 3-phase distribution section. It is non-paralleling with a split bus.

In accordance with SOLAS requirements, an emergency generator is installed above the main deck. The emergency generator is a keel cooled John Deere Tier 2 emissions certified 1800-rpm diesel engine with a Marathon generator providing 65 kW. It is supplied with a 24 V starter, 24 V controls and block heater. It is arranged to start automatically (electric start) upon loss of the ship service generators.

The emergency switchboard, also manufactured by Industrial Power Systems, will sense a loss of power from the main switchboard and automatically start the emergency generator and transfer energy loads.

Markey capstans are located on the fore and aft decks. A CEWP-90, 27 in diameter, 40 hp electric capstan is located aft. It has a rated pull of about 60,000 lb at 40 ft/minute and is capable of withstanding 300,000 lb static pull. A CEW-60, 15 hp electric capstan is located forward. It has a rated pull of about 30,000 lb at 30 ft/min.

Accommodations for 12 crew members are provided. Joiner work was completed by Marine Interior Systems of Covington, Louisiana and Oakledge Carpentry of Harpswell, Maine.

Tank capacities are as follows:

142,730 Gallon Fuel Oil

8,832 Gallon Fuel Oil Overflow

2,565 Gallon Lube Oil (main engines)

854 Gallon Lube Oil (generators)

68,354 Gallons Ballast Water

15,955 Gallons Potable Water

1,779 Gallons Dirty Oil

Washburn & Doughty is currently building two Z-Tech 7500 Class Terminal/Escort Tugs, one 92 ft Z-Drive Tug and one 93 ft Z-Drive Tug that is Washburn & Doughty’s newest in-house design. Construction at the shipyard takes place in a new, state-of-the-art building that can accommodate vessels up to 200 ft x 50 ft.

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