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– 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.

Safinah LtdIndependent Marine Coating Consultants

Providing innovative and cost effective solutions forAll marine coating issues

enquiries@safinah.co.uk Morpeth, England Tel+44(0)1670519900www.safinah.co.uk