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Antifoulings – Concerns, penalties and remedies especially for the smaller fleet operator October 7-8 - Athens, Greece The third International Symposium on Ship Operations, Management, and Economics. R L Townsin M R Kattan www.safinah.co.uk. Focus of paper. The issues of: Economy
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Antifoulings – Concerns, penalties and remedies especially for the smaller fleet operatorOctober 7-8 - Athens, Greece The third International Symposium on Ship Operations, Management, and Economics R L Townsin M R Kattan www.safinah.co.uk
Focus of paper • The issues of: • Economy • Fuel consumption • And emissions • Are all in large part a product of the performance of the anti-fouling coating. • The intention is to provide some guidance in these matters to the smaller fleet operator
Which AF Product? • The key issue for the owner is one of predictability • However factors such as: • Speed • Activity • Trading pattern • New build production requirements • Dry-dock capability • Must all be taken into account to ensure predictable performance of the AF in service
Hull roughness • At both new build and in dry-dock it is critical to ensure a low hull roughness • This is often compromised by • Cost savings • Poor control of application • Etc.
Predictability • The key elements to predictability, irrespective of the type of anti-fouling technology to be used are: • Operating cost control • Charter party performance • Anti-fouling performance to reduce unscheduled stops/delays (for hull cleaning/dry-docking).
Guarantees • Paint companies often now include guarantees • Fuel savings can be difficult to assign if other factors such as engine overhaul coincide. • What is really responsible for fuel saving or increased fuel consumption can be very dificul t to verify in practice
Development of specification • Key issue is to develop the right specification for your vessel. • Take into account the engineering needs of the coating performance and develop a “functional” paint specification as you would for any other engineering system on board a vessel. • Owner needs to establish a key set of criteria that the paint supplier must prove compliance with.
Measure of success • Enter next dry-dock foul free • Have some reserve AF left • No appreciable roughening of the hull
In service maintenance • This must be planned for hull and propeller. • Speed over performance monitoring should be set up so that hull/propeller performance can be confirmed and action taken as performance falters.
Strategy • A good strategy should have: • Attention to speed, activity levels and trade pattern • Good specification (functional) of anti-fouling system. • Use of a torsion meter to monitor in service performance • Use of Underwater hull cleaning (where possible) as interim solutions if required • Conduct of a well managed dry-docking to minimise hull roughness
Analysis • Considerable work has been done on how to calculate the resultant roughness penalties and key references are given in the paper. • Fouling penalties not so easy to assess but can be derived form speed/power monitoring. • Mini-trials during a voyage can be attempted • On board monitoring systems can be used
Performance data • In the absence of trials, monitoring systems etc and in the event of a dispute then reliance is made on deck and engine logs. • These are not aimed at collecting the data for vessel performance they can provide useful input to any analysis
Data – deck log • GPS position • Time of day • These can be used to calculate • Speed over ground • Ocean current s and winds need to be corrected for to get speed through the water.
Data – ER Log • Fuel consumption often a disappointment • Torsion meter provides most accurate and valuable data (but rarely fitted or used)
Propeller • Largest measuring instrument on board • Use of a power diagram from manufacturer can be used (details are in the written paper submission).
Summary • Guidance on choosing the right AF product • Good practice maintenance advice has been provided • Options for data gathering to allow performance monitoring to be made have been considered • The use of a shaft torsion meter has been advocated.
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