Building on its success with a proven tug design,Washburn & Doughty Associcates, Inc., East Boothbay, Maine, has begun construction of a 93 ft, 6,000 hp Z-drive tug for the Moran Towing Corporation, New Canaan, Conn.
At 93 feet by 38 feet, the tug is longer, beamier and more powerful than Washburn & Doughty’s successful 92 foot by 32 foot design, of which there are 22 tugs in operation. The increased length and beam will allow for increased horsepower over the 92 foot tug, while maintaining the maneuvering characteristics and handling capabilities that made the original design such a success.
The vessel will be classed ABS Maltese Cross A1, Maltese Cross AMS, Towing Vessel, Escort Vessel. The vessel will admeasure less than 300 gross tons U.S. regulatory tonnage.
Propulsion power will be supplied by two MTU M63L16 cylinder series 4000 main engines, each rated at 3,000 bhp at 1,800 rev/min. The engines will drive two Schottel model SRP 1515 FP drives, equipped with stainless steel propellers measuring 2,600 mm and nozzles lined with stainless steel. Bollard pull is anticipated to be 70 metric tonnes ahead and 66 metric tonnes astern.
The tug will feature a machinery alarm system assembled by First Electric Motor Services and built from Siemens components.
The tug will be outfitted with two John Deere model 6068TFM76, Tier 2 emissions certified 1800 rpm marine engines providing 99 kW, 120/208 VAC, 3-phase power. Under normal conditions one generator will be on-line for ship’s service and the other will be on standby. In the event that the on-line generator fails, the standby generator will automatically go on-line and the generator experiencing the failure will automatically shut down.
The main switchboard will be located in the engine room. It will be of the non-paralleling split bus type and be fitted for automatic transfer from the on-line generator to the standby generator. The switchboard contains PLCs to control generator shutdown, transfer and starting. Override switches will be provided to operate the circuit breaker in event of loss of 24 VDC power.
The vessel will be equipped with a Markey DEPC-48 electric hawser winch forward and a Markey CEWC-60 electric hawser capstan aft.
Bow fendering will be two courses of cylindrical fender up high along with soft loop and wing type sub fender below. A course of D-fendering, measuring 12 inch x 14 inch, will be fitted at the main deck extending from the bow fenders at the sides and around the stern.
It is anticipated that the electronics package will include two VHF radios, one loud hailer, two radars, one depth sounder, two DGPS, one AIS, one Sim-Motion System, one Blue Box System with five cameras, one Furuno RD-30 Weather Station and one satellite compass.
Accommodations will be provided for seven crew members. It is anticipated that Oakledge Carpentry of Harpswell, Maine will complete the joiner work.
Washburn & Doughty is also currently building two Z-Tech 7500 Class Terminal/Escort Tugs, one for Suderman & Young Towing and the other for Bay-Houston Towing.
Posted: January 31, 2011