NEW ON BOARD
SPONSON-DUCKTAILS:
STABILITY IMPROVEMENT WITHOUT ADDITIONAL FUEL COST
Passenger ships, especially cruise ship can often face challenges in maintaining adequate stability: conversion, refurbishment, technical upgrades and natural
weight growth all reduce the original stability margins.
Now due to new emissions regulations some Owners
choose to install scrubber systems; if there is no adequate stability margin for this, stability has to be improved in order to enable the installation.
T
he most effective way to improve stability is to install a sponson-ducktail, and Foreship has engineered several sponson-
ducktails, including Celebrity Galaxy, Seven Seas Navigator, Splendour of the Seas, Rhapsody of the Seas and Oriana.
Typical effect of sponson-ducktail on stability (example only). The
ducktail on Spendour of the Seas follows the original design of the
vessel.
The stability gain depends on the vessel size, hull form and
other characteristics, but typical example is a 40 cm improvement
Foreship ducktails have practically no effect on vessel’s speed-
in GM margin on a larger vessel. For the available deadweight
power performance: at lower speeds the additional displacement
the sponson-ducktails usually have a small positive effect, as the
and wetted surface have a small negative effect, but the fact that
displacement increase is bigger than the additional weight. The
vessel now needs less ballast usually more than compensates for
esthetical appearance of the ducktail can be designed to match
this. At higher speeds the sponson-ducktails have positive effect,
the original design of the vessel, making the ducktail look like an
and vessels usually notice increased maximum speed after duck-
original part of the ship.
tail installation. The excellent performance of Foreship sponsonducktails is based on experience and the latest CFD-tools.
More information: www.foreship.com
Oilon – LNG burners for cleaner environment
LNG/HFO/MGO marine burner
Gas valve unit (GVU)
R
eduction of sulphur content of the heavy oil for cleaner en-
fuel for ships. Solid and sulphur emissions of LNG are non-exist-
vironment causes remarkable cost increase of the marine fu-
ent. Pricewise LNG is also competitive with MGO. These features
el for the ships. As a consequence usage of heavy fuel oil is cut
boost up the usage of LNG in the future. Oilon has invested in
down considerable amounts in the ships sailing in the coastal ar-
the development of gas burners for ships recently. Today, Oilon
eas. New fuels were developed and taken in use during the last
can deliver gas burners for marine use according to most com-
years. MGO, marine gas oil, known as sulphur free light oil, Oilon
mon classification societies. Entering in the marine field was very
as a leading marine burner manufacturer, dominates already the
natural continuation of the long experience of the gas burners in
combustion of this fuel very well. Our recipe for success has been
the land based installations.
innovation and human capital.
LNG, liquefied natural gas is coming as a cleaner alternative
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More information: www.oilon.com