“A BULBOUS BOW FITTED TO A VESSEL REDUCES RESISTANCE AGAINST THE WAVES. IT GENERALLY WORKS BETTER AT SOME DRAUGHTS AND SPEEDS THAN OTHERS, SO IT SHOULD BE OPTIMISED FOR THE MOST IMPORTANT SAILING CONDITIONS” Gunnar Malm Gamlem, naval architect.
ZHOUSHAN: Tamesis, Tarago and Tamerlane are equipped with more fuel efficient bulbs following a successful docking at the IMC-Yongyue (IMC-YY) repair yard in Zhoushan, China. Staff worked around the clock to complete the project: eight days on Tamesis and six days on Tarago. These were both well within the usual dry-dock time.
Since September 2014, vessel manager Ivar Ørbog and naval architect Gunnar Malm Gamlem have worked with IMC-YY to prepare the yard’s first ever bulb conversion. “Our cooperation has been constructive and we appreciate IMS-YY’s preparations and hard work,” says Gamlem.
A floating crane transported the new 130-tonne bulb to the yard, where a custom-made railway carriage ensured safe movement and precise adjustment to the existing hull.
The project was initiated when operations data from our in-house developed Performance Monitoring & Analysis (PMA) tool confirmed the vessels were operating on a lighter draft and lower speed than they were designed for. “Built in 2000, the vessels were originally designed to carry heavy cargo such as timber products and paper pulp, cargo which is less frequent today”, explains fleet performance analyst Anders Lenning.
THE NEW BULB designed by Daewoo Shipbuilding & Marine Engineering (DSME) is better tuned to the modern cargo mix and operating speeds. It was horoughly tested at SSPA in Gothenburg to verify performance and, depending on the fuel price, the payback period for the project should be less than two years.
With the conversion of Talisman in June, four of WWL’s largest ro-ro vessels will be more energy efficient.