Netherlands-based OSD (Offshore Ship Designers) has designed a new series of tractor tugs which can be used for a range of functions, including escort operations, harbor towage, ship handling, offshore mooring and berthing.
The basic model tug has a LOA of 33 meters and a beam of 13.5 meters, but the tug design can be tailored to various sizes. According to the designer, the high forecastle deck ensures good sea-keeping performance. The hull is shaped with side wings to reduce drag, enhance stability and to improve roll-damping, ensuring the vessel is suited for offshore towing and salvage, OSD said.
The wheelhouse design gives an excellent overview of the work-deck during escort operations and optimum visibility over the bow during transit modes.
A broad tow-staple on the aft-deck reduces moment of inclination caused by tension on the wire, while the spacious aft-deck itself accommodates the towing winch. The aft bulwark structure is outfitted with an integrated tow-pin arrangement. A knuckle-boom crane is outfitted with outreach over the aft-deck area.
The tugs can be fitted with either Voith Sneider cycloidal propellers (the Cyclotrac 3270 model) or azimuthing thrusters (the Azitrac 3270 design). The propulsion drive configuration can be adapted to client specification – diesel-electric, hybrid with or without batteries etc. Depending on engine and propulsion configuration, a bollard pull of 90 metric tons can be achieved.
OSD’s MLC-compliant tugs can be delivered with a FiFi1 class notation. They have accommodation for 8 to 12 persons, with individual sanitation facilities.