Case study
Voith Schneider Propeller
Platform Supply Vessel with Voith Schneider Propeller
Edda Fram Fights any 5 Meter Wave
Captain Dagfinn Thorbjørnsen has been working for the Norwegian shipowner Østensjø for 20 years.
For three years now, the Edda Fram, a platform supply vessel, has been under his command. Its journeys from
Aberdeen to the Shell oil fields in the North Sea take approximately four days. “I wouldn't want to switch
to any other vessel any more”, he says. “With its Voith Schneider Propeller (VSP), the Edda Fram can be
controlled reliably and precisely with the help of a joystick”.
Shell has chartered the Edda Fram
until 2011 with an option for another
five years. It supplies the platforms
in the Brent oil field north of the
Shetland Isles. Out at sea, waves of
up to four or five meters are com-
Voith Turbo | Case study VSP
monplace in this region; during
severe storms, they may even pile
up as high as ten meters. The
crossing from Aberdeen to one of
the 16 Brent platforms takes approximately 20 hours. These platforms
are named after letters from the
Morse alphabet: Alpha, Bravo,
Charlie, Delta... The vessel stays
at the platforms for two days before
it returns to Aberdeen laden with
wastewater, dirt and drilling mud.
The supply vessel is entering
the prohibited 500-meter-zone
around the platform.
The two Voith Schneider Propeller are only visible in the dry dock. Each of them has five blades that rotate together.
On the right: Joystick instead of steering wheel. Captain Thorbjørnsen firmly in control of the two Voith Schneider Propeller.
During these two days, the platform
crews are supplied with water, diesel
fuel, methanol, cement and any kind
of equipment needed.
The Edda crew relies on the VSP.
“Dynamic positioning” (DP) is the key
word as this is one of the strengths
of the VSP. The Edda must not leave
any predetermined position by more
than four meters. After three meters,
a loud warning signal is emitted.
However, dynamic positioning allows
the maximum actual deviation to be
a mere 80 centimeters, even in four
or five meter waves. Unwanted ship
movements which may result in
disruption of the transfer hoses while
loading hazardous goods and consequential dangerous situations
can thus be avoided.
“What I like best is the fast reversing,
from full speed ahead to full speed
astern in just five seconds!” compliments Captain Dagfinn Thorbjørnsen
of the Edda Fram and adds:
“The minimal vessel motion during
dynamic positioning is almost too
good to be true. When at Brent B
Voith Turbo | Case study VSP
with four meter waves, we had set
the VSP to low speed and the DP
limit to one meter only. The Edda
remained in position for three hours
with one small deviation alarm only.
All ships I commanded previously
have been good. But the Edda Fram
and the VSP are simply fantastic”.
Shell benefits on that by savings on
the fuel bill: “In general, the fuel
consumption is low on these VSP
ships” they say, “and when it comes
to DP operations the fuel consumption is considerably lower than on
other vessels of that kind”.
Increase of Comfort
and Save Cargo Transport
In huge seas the Captain additionally activates the Voith Roll Stabilization. Not only does it increase
the comfort for the crew but it also
enables the crane operator to transfer its cargo safely and fast to the
platform. Seamen can tell many
stories about this not always being
a routine operation in heavy seas.
Captain Thorbjørnsen enjoys
recounting an incident where he
had Shell representatives on board.
On this November day, another
vessel tried in vain to dock on Brent
Delta and Brent Charlie. “We arrived
at the Brent oil field at the same
time, docked on the platform despite
five meter waves and were able to
unload our cargo fast and reliably.
The Shell representatives were
impressed”.
This may also have been the reason
why Shell decided to charter two
VSP vessels long-term: the Edda
Fram as well as its sister-vessel
Edda Frende. Whenever something
needs to be delivered to the oil
platforms under the most adverse
weather conditions, Shell now
always uses the Edda Fram or
Edda Frende.
Advantages in Reliability,
Service and Spare Parts
In the past three years since its
commissioning, the Edda Fram has
accumulated 18 000 operating hours.
This timeframe is normally associated with a maximum 12 000 operating
Voith Turbo, the specialist for
hydrodynamic drive, coupling
and braking systems for road,
rail and industrial applications,
as well as for ship propulsion
systems, is a Group Division
of Voith AG.
Voith is setting the standard in the
paper, energy, mobility, and
service markets. Established on
January 1, 1867, Voith is now one
of the largest family-owned businesses in Europe, with 39 000 employees, 5.1 billion euro in sales,
and over 280 locations worldwide.
Voith is an official partner of
the initiative “Germany – Land
of Ideas”.
Edda Fram on its way home to the Aberdeen Quay, the heart of the British oil industry.
hours. When travelling to the Aberdeen dock for regular service, Voith
service engineer Frank Horn therefore brought entire replacement
sets for the blade shaft seals. However, following removal of one
propeller blade each and carrying
out a detailed analysis, it became
clear: Neither seals nor propellers
displayed any significant wear and
are absolutely ok.
“We know” says Carl Johann Amundsen of the shipowner Østensjø,
“that VSP systems are more expen-
sive than other propulsion systems.
However, in terms of reliability, service and spare parts, Voith has way
more to offer. Whilst the purchase
cost of the VSP may be higher in
direct comparison to other propulsion
systems in similar vessels, the costs
for repairs of other systems is twice
that of the difference in purchase
price”. The owners of the Edda
Fram and Edda Frende therefore
make no secret about thinking
of further vessels which are to be
equipped with Voith Schneider
Propeller.
Media contact:
Adela Trstenjak
Central Advertising / PR
Phone +49 7321 37 2594
Fax
+49 7321 37 7110
E-mail [email protected]
Internet www.voithturbo.com/marine
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