February 7, 2006
Washburn & Doughty delivers escort tug
Washburn & Doughty Associates, Inc. of East Boothbay, Maine has delivered the Bulldog, a 98 ft x37 ft, 6,700 HP, Z Drive firefighting tug, to Crescent Towing of New Orleans.
Bulldog provides ship-assist and escort services for LNG tankers at the Elba Island LNG re-gasification terminal in Savannah, Georgia.
Bulldog's sistership, Edward J. Moran, is currently under construction at Washburn & Doughty for the Moran Towing Corporation and on completion will join Bulldog at the Elba Island terminal.
Washburn & Doughty is also building an 80' Z Drive Tug, designed by Robert Allan Ltd., for Wilmington Tug and two 92' Z Drive Tugs for Moran Towing.
Bulldog has been built to a new Washburn & Doughty in-house design and is the first tug built at the yard for Crescent Towing.
Bruce Washburn, Washburn & Doughty's Chief Naval Architect and Vice President, drew on the company's extensive experience designing and building Z Drive Tugs for ship docking and LNG operations while designing the tug.
Since 1999, the company has designed and built 18 Z Drive Tugs, six of which are used at LNG terminals.
The new 98 ft design maintains a traditional look while providing 360 degrees visibility in the pilothouse.
Underwater, the vessel features a deep box skeg designed to enhance escorting without sacrificing maneuverability.
Throughout the design process Washburn & Doughty received significant input from Crescent, Moran Towing Corporation, the shipping companies and their consultant, Greg Brooks.
In addition, Washburn & Doughty contracted with Glosten Associates to analyze the tug's escort capability using its escorting computer model. Glosten predicted that at 8 KTS the tug will have steering forces of 75.6 ST and braking forces of 116.2 ST.
Bruce Doughty, Washburn & Doughty's President & CEO points out, "We have worked on numerous tug bids for LNG operations lately and thereby become very familiar with what terminals and shippers are looking for in a vessel. Our 98 ft tug addresses what LNG operations need in a tug, particularly as it pertains to power, maneuverability, escorting and firefighting capabilities."
Bollard pull tests on January 10 in Newport News, Va. gave the following results: Forward Mode Ð 180,000 lb (90 Tons); Forward Mode Max Ð 182,000 lb (91 Tons).
Bulldog is classed ABS Maltese Cross A1, Maltese Cross AMS, Towing Vessel, Fire Fighting Class 1, Escort Vessel.
The Firefighting 1 classification requires two monitors to each produce 5,280 gallons per minute for a distance of 394 ft at a height of 148 ft, as well as a deluge system and the ability to sustain firefighting operations for a minimum of 24 consecutive hours.
Firefighting 1 equipment includes two Caterpillar 3412C engines rated at 900 hp at 2,100 RPM and Nijhuis HGTFI-1-250.500 pumps located in the engine room.
The pumps supply two remote controlled FiFi 1 monitors mounted on the aft upper deck. Controls for the monitors are in the pilothouse and locally at the monitors. The firefighting system also includes a deluge sprinkler system and eight (8) fire stations located on the main deck.
Bulldog is powered by two medium speed GE 7FDM12 main engines that each produce 3,350 hp at 1,050 RPM.
The propulsion system is completed by Rolls Royce model US255 Z Drives with 2800mm, 4 blade, stainless steel propellers.
Bulldog is equipped with John Deere model 6068TFMGK-99, Tier 2 emissions certified, marine generator sets providing 99 kW @ 1,800RPM, 208V 3 phase power.
One generator is normally on-line while the other is on standby. In the event that the on-line generator fails, the standby generator will automatically start and go on line. The generator experiencing the failure will be automatically shut down. The main switchboard provides for automatic paralleling of the generator sets and is integrated with the winch controls. The online generator provides sufficient power to operate the winch in normal (assist) mode. When high power (escort) mode is selected, the standby generator is automatically paralleled with the online generator.
The bow is fitted with a Markey type DESF-48, 100 hp electric escort winch. The winch drum holds 750 ft of 9 inch synthetic line. The winch features line-pulls up to 365,000 lbs. at 0- 8 FPM; line-speeds up to 600 FPM; and a drum brake holding capacity of 476,000 lb utilizing an Eaton water cooled brake.
A 15 hp Markey CEWC-60 electric stern hawser capstan is located on the aft deck and a 5 hp Markey CEP-40 electric messenger capstan is fitted on the foredeck.
Bow fendering includes 12 inch x14 inch rectangular molded rubber on the upper section; 16" soft loop on the middle section; and a "Turk's head" style fender on the lower section. 12 inch x14 inch rubber "D" fender is fitted at the main deck on the sides and stern.
Accommodations are located in the deckhouse and include a mess/galley; four two man staterooms, two heads and lockers.