Transcript 45_Athens-antifouling-speed-emissions-Oct-2010x

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 Ltd
Independent Marine Coating Consultants
Providing innovative and cost effective solutions for
All marine coating issues
[email protected]
Morpeth, England
www.safinah.co.uk
Tel+44(0)1670519900