AT THE DRY DOCKS IN TRIESTE, ITALY

Impeller
69:2005
SHIPS KEPT IN SHIPSHAPE
AT THE DRY DOCKS
IN TRIESTE, ITALY
RELIEF FOR SAINT-MALO YACHTSMEN • STEPHEN PAYNE: MAKER OF QUEENS
69:2005
Sea changes
I
PER-INGE BIRGERSSON
President, ITT Flygt
OUTLOOK: POLLUTERS PAY A HIGH PRICE, as big cruise lines have found
out. But ports could do more to help them.
7
AMATEUR YACHTSMEN are welcome to the port town of Saint-Malo in
France, but their sewage is less welcome, particularly when it goes
straight into the harbour. When the port became contaminated
with waste from pleasure boats, the town’s chief engineer, Jacques
Bellec, found an innovative solution.
11
OPINION: THE INTERNATIONAL MARITIME ORGANISATION’S secretary
general, Efthimios E Mitropoulos, discusses the latest policies on
how a ship’s sewage should be handled.
12
SINCE THE TIME of the Romans, the Italian city of Trieste has been
famous for its shipbuilders and seafarers. Today their prowess
continues, with a flourishing business based on the largest dry
dock in the Adriatic.
14
PROFILE: NAVAL ARCHITECT STEPHEN PAYNE’S love for huge ocean-going
vessels is evident in one of his latest jobs: designer of the Queen
Mary 2.
17
WHEN PEOPLE BEGAN to pour into an area situated along Australia’s
southeastern coastline the local sewage treatment plant began to
strain under the load. Flygt provided the ideal solution.
19
ON THE SURFACE: NEWS from around the world.
20
WATERTIGHT: SMALL BUT TOUGH, Flygt’s new Ready pumps are in a
class of their own in the submersible pumps segment.
22
WATERTIGHT: THINKING ZINC is all it takes to prevent iron pumps from
being corroded when submersed in seawater.
4
PHOTO © MAGNUS FOND
n this issue of Impeller looks to the seas,
where there is currently a boom in the
transportation of goods and people.
The entire maritime industry is a huge market
that is currently experiencing much growth.
The boom in the shipping industry, with overloaded ports as a consequence, generates a
high demand for construction of new and larger
vessels to meet the projected demand. Asian
shipyards, for example, are fully booked for
years ahead so they need to extend their facilities or build new shipyards to avoid losing
orders. The high demand from shipowners
for fast deliveries of new or converted vessels
have resulted in orders being placed at shipyards in Europe and America.
Just as on land, the need for up-to-date
infrastructure to handle increased traffic is
great. Harbours and marinas around the world
are faced with a range of capacity and handling
issues. One of the biggest areas of concern –
and need – is helping the industry to follow
tough but much-needed environmental regulations that make sure the world’s oceans, ports
and harbours remain clean. On page 11,
Efthimios E Mitropoulos of the International
Maritime Organisation explains what is in store
now and in the near future regarding such
regulations.
A wide range of companies, organisations
and local governments are already finding
effective ways to solve their problems. Flygt
has done its part offering practical, simple
and flexible solutions that work for big or
small jobs, with submersible or dry-installed
pumps. Whether it’s smart toilet solutions
at Saint-Malo’s harbour on the Breton coast
in France (page 7), or keeping drydocks in
Trieste in top condition (page 12).
4
20
Impeller
7
A NEWS MAGAZINE FROM ITT FLYGT AB WWW.FLYGT.COM
Publisher: Henrik Stridsman/ITT Flygt AB Editor: Karin Bergfors, [46] 8-475 68 53
Mail: SE-174 87 Sundbyberg, Sweden e-mail: karin.bergfors@flygt.com
Publishing agency: Appelberg, Stockholm, [46] 8-406 54 00
Managing editor: Bert Menninga Editors: Eriq Agélii, Anne-Mette Thunem Herre
Language coordinator: Maggie Hård af Segerstad Copy editor: Valerie Mindel
Design: Göran Hagberg Print: Trosa Tryckeri 2005
ISSN: 0345-5181 Cover photo: Maurizio Camagna
Editorial board: Margot Heintz, Andrea Mariani, Trevor Parrett, Raymond Simond
Impeller is published three times a year in Danish, Dutch, English, French, German, Italian,
Norwegian, Spanish and Swedish.
2 Impeller
A NE W S M AG A ZINE F RO M IT T F LYGT
Oil on the water
While efforts to avoid oil spills on the
open sea and coastal areas have resulted
in fewer such spills, researchers continue
to look for ways to minimise the damage
when spills do occur. In such research
efforts, simulation is a very useful tool
to understand how oil spreads and drifts
on water.
The Coastal Engineering Laboratory at
the Technical University of Bari in Italy
has undertaken an advanced oil-spill
simulation project. The mathematical
models created under the project are
analysed with software developed by the
Danish Hydraulic Institute. The physical
simulation is performed in a 12,000square-metre facility with variable water
temperature and depth capacities and
movable wave makers. There is also a
large channel for the study of streams
and ocean circulation.
An NZ 3152 Flygt pump was chosen
for handling the water at this facility
because of its reliability, efficiency and
low energy consumption and maintenance costs.
PHOTO UNIVERSITY OF BARI
¶
¶
PHOTO REUTERS
On the surface
Torgeir Sæverud (left) and Olav Heyerdahl (right) show the route they’ll take in their balsa
raft, following in the tradition Olav’s grandfather, Thor.
Kon-Tiki sails again
In 1947, Norwegian Thor Heyerdahl sailed in a balsa raft, the Kon-Tiki, from
Peru over the Pacific to Polynesia using only the most rudimentary navigation
tools. The success of Heyerdahl and his team proved to the world that ancient
mariners could, in fact, have travelled across the Pacific.
Now another Heyerdahl and another Kon-Tiki are preparing for a new adventure, to draw world attention to the environmental threats to the oceans. This
time the balsa raft will be equipped with high-tech navigation and communication systems. And at the helm will be 27-year-old Olav Heyerdahl, the grandson
of Thor, who died in 2002.
During the journey, supported by both the Norwegian government and the
United Nations Environmental Programme, the crew of five will perform continuous tests of the water to assess current levels of contamination.
You can follow the expedition’s progress through the Internet at
www.tangaroa.no.
Sewage non-stop
At a wastewater treatment plant in Poteau,
Oklahoma, in the US, sharp objects
carried by sewage inflow were causing
repeated failures of a diaphragm pump.
This resulted in disruptions to the operation of the plant, and in addition the plant
received written warnings about the
adverse environmental impact.
To solve the problem, the local public
works department considered a costly
overhaul of the entire grit chamber where
the pump was situated.
But first the engineers turned to an
alternate solution – using a heavy-duty
Flygt pump of the kind used in industrial
and mining applications. A Flygt HS 5100
slurry pump equipped with a case-hardened
A NEWS MAGAZINE FROM IT T FLYGT
impeller and agitator was fitted
in the existing structure.
According to official reports,
the new pump solved the
problem entirely, plus it had
a much higher sustained efficiency than the older one.
And best of all, the price tag
was a 10th of the cost of an
overhaul.
PHOTO CITY OF POTEAU
¶
¶
Instead of overhauling the grit
chamber, Poteau, Oklahoma in the
US bought an HS 5100 pump.
Impeller 3
¶ Outlook
Illegal wastewater dumping
by cruise liners has spurred
strong measures in the fight
against pollution at sea. But
more needs to be done.
Avoiding
trouble at sea
TEXT GRAEME FORSTER PHOTOS GETTY IMAGES
he cruise ship industry is enjoying
a boom. According to the International Council of Cruise Lines
(ICCL), an association that represents
the interests of American-based cruise
line companies, 9.8 million passengers
were carried by ICCL members during
2003, a 6.6 percent increase over 2002.
The rebound in the global economy and
lower fares encouraged travellers, and
T
4 Impeller
optimism spurred contracts for everlarger ships: the 150,000-tonne, 2,620passenger Queen Mary 2, the biggest
cruise ship in the world when she was
launched in 2004, will be superseded
by the 160,000-tonne, 3,600-passenger
Ultra Voyager class in 2006.
Cruise-taking is big business, which
is why no cruise company wants to be
tarnished with the reputation of being a
dirty player. This is what nearly happened
when, in 2002, three of the largest lines
were found guilty of dumping untreated
sewage and wastewater into the seas
around Miami and Alaska and then trying
to hide the fact by falsifying records. The
US Justice Department handed out fines
ranging from 1 million to 18 million US
dollars and temporarily banned one
company from Alaskan waters. Their
A NE W S M AG A ZINE F RO M IT T F LYGT
punishment, together with the threat of
prohibition from US waters, began a
scramble among the biggest companies
in the cruise industry to embrace more
environmentally responsible corporate
policies and more effective on-board
treatment technologies.
Sewage and waste products from all
sorts of ships, including cruise ships, is
a significant factor in the pollution of
A NEWS MAGAZINE FROM IT T FLYGT
seawater – although some 77 percent of
the total of that pollution comes from
land-based discharges and atmospheric
inputs. Oil is another significant polluter,
mostly through normal ship operations
rather than spillage and accidents. But
whereas oil spillages have decreased in
size and number since the International
Tanker Owners Pollution Federation
began keeping records in 1974, the threat
from the volumes of ship-generated
sewage and wastewater has still only
vaguely been estimated.
Ships produce liquid waste in a
variety of forms. Black water is the
sewage from toilets and sculleries. Grey
water is wastewater from bathing and
washing-up facilities. A large cruise
ship produces around 900 cubic metres
of mixed black and grey water every
Impeller 5
day. (Large cargo vessels and tankers
have much smaller daily outputs, since
they carry very few crew or passengers).
A treaty restricting the pollution of the
seas by ship-generated wastewater has
been drawn up by the International
Maritime Organisation (IMO), a United
Nations body with 164 member states.
Annex IV of MARPOL 73/78 (full title:
The International Convention for the
Prevention of Pollution from Ships, 1973,
as modified by the Protocol of 1978
relating thereto) deals with the prevention of pollution by sewage from ships.
For instance, ships may discharge
untreated sewage into the sea provided
the vessel is beyond 12 nautical miles
from land. Between 12 and three nautical
miles, sewage must be comminuted
(reduced to fragments) and disinfected.
Discharging is prohibited closer than
three miles to shore.
Who enforces IMO regulations? Lee
Adamson, head of Public Information
Services at IMO headquarters in London,
says “The enforcement of IMO instruments is carried out by the member governments. Flag states must ensure that
ships flying their flag meet the appropriate requirements and will put in place
a survey, inspection and certification
process to ensure that they do. Many
IMO Conventions also allow for coastal
states to board foreign flag vessels visiting their ports to check that ships are in
proper compliance with the instruments
to which their flag state is party.”
MARPOL Annex IV obliges all states
party to the convention to be in a position to offer appropriate facilities for
handling sewage and waste material. But
meeting sewage treatment requirements
is an expensive business. And some
desirable cruise locations in protected
areas – such as around the Alaskan coast
– have higher environmental regulations
and fewer facilities than elsewhere. This
helped put pressure on the guilty cruise
companies to cheat and try and cover
up the evidence. But these were just the
ones who were caught.
Ports could do more by making it easier
and quicker for vessels to off-load wastewater into purpose-built treatment
facilities. Surprisingly, most of the world’s
biggest ports rely on bilge boats or
vacuum tankers to collect waste from
ships. Too bad if the stop is short and the
bilge boat is busy. This is why initiatives
such as that undertaken by the Ports of
Stockholm (see page 10) to build a dedicated
sewage-handling solution deserve praise.
Thanks in part to Alaska and Miami,
today all cruise ships are built with
efficient on-board treatment facilities.
But there are still several thousand older
cruise ships pottering around the paradise
spots of the planet. These ships cannot
be retrofitted with modern wastewater
handling systems, either because of
their design or because of the expense
involved. If they are to comply with the
environmental obligations of the IMO,
they need a little help. ¶
Sea pollution and the
International Maritime
Organization
In 1948 an international conference in Geneva adopted a
convention formally establishing the Inter-Governmental
Maritime Consultative Organisation (IMCO), the forerunner
of the IMO. It had as a stated goal “to encourage and
facilitate the general adoption of the highest practicable
standards in matters concerning maritime safety, efficiency
of navigation and prevention and control of marine pollution
from ships.”
Although a first treaty was adopted in 1954 dealing with
oil pollution from ships, the threat of pollution was not fully
realised until 1967, when the tanker Torrey Canyon ran
aground off the coast of Britain and spilled 120,000 tonnes
of oil. Up to this point, the seas were thought to be big
enough to cope with any pollution from human activity.
Since then IMO has adopted a series of conventions covering
marine pollution by ships. Annex IV of MARPOL, which
deals with the prevention of sewage from ships, entered into
force in September 2003. It has now been ratified by
100 countries whose combined merchant fleets constitute
nearly 55 percent of the world’s merchant fleet by tonnage.
6 Impeller
A NE W S M AG A ZINE F RO M IT T F LYGT
Outlook
¶
Floating facilities
Protection of beaches against pollution and keeping the water
clean represents a major challenge for Jacques Bellec, chief
engineer of the medieval town of Saint-Malo in France.
TEXT AND PHOTOS ERLING SÖDERSTRÖM ILLUSTRATION ANN-SOFI MARMINGE
ituated on the north coast of
Brittany in France, where the
tides entering the narrow English
Channel are the highest in Europe, the
town of Saint-Malo attracts hundreds
of thousands of holidaymakers each
year who are looking to enjoy the
spectacular rocky coastline and sandy
beaches. The town has 53,000 permanent residents, but during the summer
months there can be four times as many.
And a hefty portion of these will be using the harbour facilities.
S
A NEWS MAGAZINE FROM IT T FLYGT
Saint-Malo is proud of its maritime
tradition. It was from here that in the
past privateers and explorers set sail. In
more recent times the yachting resort
of Les Sablons, along Saint-Malo’s harbour, has become an obligatory point of
departure for several major ocean races.
It has more than two kilometres of pontoons and accommodates 1,300 pleasure
vessels of all sizes.
Jacques Bellec has been in the service
of the town council for 27 years, trying
to keep the town’s waters clean. It is
mid-week at the end of autumn and
there is no longer the right wind for
putting out to sea. The boats are awaiting
their owners who come at the weekend
or during the holiday season.
“More and more boats have become
year-round residences and never leave
the port,” says Bellec, the town engineer
and the person in charge of keeping the
harbour waters clean. “Converted into
floating hotels, they are frequently rented by visitors to the town, all of whom
need sanitary facilities.”
There are approximately 20,000
overnight stays in the port every year,
and despite a European directive from
2000 that requires all vessels to have a
retention tank for their toilets, the owners often empty the contents directly
into the sea.
Impeller 7
The port of Saint-Malo is a popular tourist destination in Brittany, famed for its walled city.
Saint-Malo faces the English Channel on
France’s Emerald Coast in the department Illeet-Vilaine, a part of the region of Brittany.
Jacques Bellec is the town engineer for Saint-Malo and the man responsible for making sure the
harbour waters stay clean.
Awareness of this ecological problem
goes back to the Cutty Sark regatta
in 1999, when the port played host to
87 tall ships and their crews, totalling
3,500 people, not counting the visitors.
With these numbers, water pollution
grew to the point where the neighbouring
beach was classified as “C,” meaning
swimming was temporarily prohibited,
and a surfers’ association christened
Saint-Malo the “Jolly Roger.” The
publicity surrounding these events
threatened to dampen the town’s appeal
to tourists – an important part of the
local economy. Bellec knew something
had to be done.
“It was time to change all the old
pontoons that had been in service for
8 Impeller
a good 20 years, anyway, so I agreed to
deal with this on the condition that I
was allowed to address the problem
of water pollution at the same time,”
Bellec recalls.
For more than a year, Bellec looked at
solutions that had been implemented in
other European countries that had similar problems, but he could find nothing
that would be appropriate.
“I sat down in front of a blank sheet
of paper and started to reflect on the
whys and wherefores,” he says.
Up until the year 2002, a skipper who
felt the call of nature had to leave his
boat, cross the pontoon, climb a gangway, which sometimes meant climbing
13 metres, and then walk 200 metres to
join a queue outside the toilets – while
trying not to forget the access code,
which changed every week. Under
these conditions, the majority of “boat
people” preferred to use the toilets
on board, whether or not they were
equipped with a retention tank.
“I decided it would be better to bring
them [the people and the toilets] closer
together,” says Bellec. “The solution
was to install two toilet cubicles on each
floating pontoon, which would be a
maximum of 50 metres away from the
boats and would facilitate the emptying
of the retention pans and wastewater.
Initially, no one thought it could be done.
They said that in stormy weather the
waste would fly out and stick to the walls.”
A NE W S M AG A ZINE F RO M IT T F LYGT
Outlook
¶
At right, Saint-Malo has gotten smart
about handling the needs – and the
wastes – from visitors who come by
boat. The solution? Better toilet facilities that include both public toilets as
well as a means to get rid of waste
from boats, including from chemical
toilets.
Smart toilet solution
The solution faced various constraints
– for example, keeping the water back
in an area that experiences 12.6-metre
tides – among the highest in the world.
The architecture had to fit in, but the
materials had to be strong, light, easy to
maintain and resistant to water swells
and to vandalism.
The port is now equipped with three
new pontoons, each of which have two
modules containing a toilet, a chemical
container and a technical unit. The other
pontoons will gradually be replaced
over the years to come.
At present, during the high season the
toilets are used about 200 times a day on
each pontoon. The advantages of these
A NEWS MAGAZINE FROM IT T FLYGT
At Saint-Malo’s harbour, a pressurized sewage system handling waste water from pleasure
boats has been implemented. The wastewater from the port’s toilets is evacuated by
submersible Flygt Grinder pumps, MP 3068 HT 212 pumps with 1.7 kW motors and
weighing 31 kg, installed in TOP 50 pumping stations fixed underneath toilet modules.
An external tank, linked to the toilet, allows visitors to get rid of the water from their
laundry, washing-up or chemical toilets. A suction pipe along the entire 17 metres of the
pontoons allows users to evacuate the contents of their own retention tanks as well. The
effluent is then delivered to the town’s sewage treatment plant via a network of pipes
branched under pressure. Two toilet modules can be found on each of three pontoons.
Each module features three sections: a public toilet, a chemical container and a technical unit. The toilets are light and semi-floating and can easily be unscrewed and moved
elsewhere. Plans are to outfit the rest of the port with additional modules.
new facilities are obvious. In port, boat
owners can keep their own toilets cleaner
and fresher-smelling because there are
more spacious floating facilities on the
pontoons. The user no longer needs to
remember an access code to get in.
Thanks to the resistant material, users
can sit quietly reading a book in the
cubicle while a 100 km/h gale is blowing
outside. The town itself has saved its
public image, and the beaches continue
to attract holidaymakers.
In December 2004, Saint-Malo’s
efforts were recognised by the Salon
Nautique de Paris, which awarded the
town with a prize for innovation.
“Brittany covers a good part of the
French coastline,” says Bellec. “It has
ports everywhere and pollution to
match. Now I am trying to show our
example to neighbouring ports, and
many communities have come to study
our solution.” ¶
Impeller 9
No dumping
The Ports of Stockholm has been an earlier adopter of more
efficient systems for handling wastewater from ships.
TEXT GRAEME FORSTER PHOTO POS
n any given day, two dozen large ships will enter or
leave the three harbours that make up the Ports of
Stockholm (PoS) in Sweden. In 2003, cruise liners,
ferries, bulk carriers and oil tankers accounted for more than
10 million passengers and 5.5 million tonnes of freight. This
amount of traffic makes Stockholm one of the largest ports on
the Baltic, and in fact the PoS rates as one of the most important
harbours in the northern region. It is also one of the most
active ports in the world in terms of environmental awareness.
Having achieved a 43 percent cut in the nitrogen oxides
given off by visiting ships (it won an environmental award
from the European Union), PoS is working towards more
efficient handling of ship-generated wastewater. Since 1973,
directives from the International Maritime Organisation
have required governments to provide sewage reception
facilities at ports, and at the same time have banned the
dumping of untreated sewage within 12 nautical miles of
land. Usually, once a ship arrives, its sewage is pumped into a
O
tanker truck and driven away for disposal. But with the
volumes involved (more than 320,000 cubic metres in 2003)
and the short time that many cruise liners stay in port, Stockholm wanted a solution that made the process of handling
wastewater as quick and easy as possible.
Working together with Flygt and the shipping companies
involved, PoS has built a series of connection points into the
berths at the dockside. These allow sewage from ships to be
transferred directly to a dedicated harbour-based pump station;
from there it is piped to the local sewage network. With the
planning process begun in 1995, Stockholm has been one of
the world’s earliest adopters of technologies to deal with shipgenerated wastewater. PoS and Stockholm Vatten, which
provides drinking water and water treatment for much of the
Stockholm area, now have a total of eight pumping stations in
operation to deal with wastewater from ships. PoS is pleased
with the results and plans to extend these facilities to more of
its harbours. ¶
The heart
of the matter
The design of the sewage pump stations
for the Ports of Stockholm was developed
in consultation with Flygt as a way to
deal with large amounts of sewage with
a high-solid content from Baltic cruisers.
These cruisers often demand a quick
turn-around in port, so reliability and
resistance to clogging was vital. Flygt’s
N-pump fit the bill perfectly with its efficiency and patented anti-clogging design.
The bottom of the pump station also
played a key role here: Flygt’s TOP shape
ensures agitation of any solids that settle,
making them easier to pump away and
keeping the station cleaner over time.
10 Impeller
A NE W S M AG A ZINE F RO M IT T F LYGT
Since Roman times, Trieste has been an important center for ship-building. While the shipyard continues to be modernised, some things have
changed little over the centuries.
Keeping dry docks dry
At the dry dock in Trieste in Italy, new pumps provide the flexibility
needed to accommodate huge cruise ships.
TEXT CLAUDIA FLISI PHOTO MAURIZIO CAMAGNA ILLUSTRATION ANN-SOFI MARMINGE
rieste, at the head of the Adriatic Sea in northeast
Italy, has since Roman times flourished as a one of the
largest ship-building centres in the region. The city’s
first dry dock for the repair of large boats was built in 1858
and is intact today, testimony to the skilled hands that
constructed it.
The maritime industry continues to be a main contributor
to Trieste’s economy. So it is no surprise that Fincantieri, one
of the largest shipbuilding groups in Europe, chose the city
for its operational headquarters.
T
Fincantieri was created in 1959 as a holding company for Italian
shipbuilding activities and represents two centuries of designing
and building ships. It encompasses the construction of more
than 7,000 sea vessels in nine different locations around the
Italian peninsula. The same year it was founded, Fincantieri
opened a dry dock in Trieste with a capacity of 20,000 dead
weight tonnes (DWT).
12 Impeller
In 1970, the company merged two facilities in Trieste, the
Arsenale Triestino and Cantiere San Marco, to create
Fincantieri ATSM, (commonly referred to as ATSM).
In 1984 Fincantieri opened a dry dock in Trieste with a
capacity of 140,000 DWT, the largest dry dock in the Adriatic.
It is 295 metres long by 56 metres wide, with a depth of
12 metres. This greatly expanded the facility’s capabilities
beyond the existing dock of 20,000 DWT built in 1959.
Also in 1984 Fincantieri became an operating company. At
the time, ATSM was used for both ship construction and repair.
But in 1996, says Mauro Cappellari, general manager of
ATSM, “headquarters decided to rationalise its facilities and
close down construction activities here, so our business is
dedicated to managing the dry docks.”
Demand for servicing has increased in recent years, so much so
that vessels are sometimes lined up to enter ATSM’s large dry
dock. Part of the demand comes from the world’s growing
A NE W S M AG A ZINE F RO M IT T F LYGT
Dry docks
Dry docks are built in sheltered harbours alongside the
waterfront. They are closed by hydraulic gates after a vessel
enters. Once the ship is in place, pumps remove the water
from the dry dock, pumping it back into the harbour. This
process can take several hours, depending on the size of the
dock, the ship and the pumps.
The ship must be positioned on keel blocks to keep it from
tilting when the water is drained. The study of keel block
placement takes place before the ship enters the dock, one
step in a five-day preparation period for each new vessel.
When work on the ship is finished, water is allowed to
re-enter the dry dock and the ship is carefully refloated.
The gate opens and the ship is manoeuvred out to the sea.
Among the many tasks that vessels require when it comes to maintenance and repair, one of the first when the ships hit the drydock is
being sprayed with compressed water to clean off all encrustations.
Nereo Pieri, is shipyard manager for Fincantieri ATSM. Standing in the
control room above the shipyard, he oversees the repair and maintenance of the ships that make their way to Trieste.
appetite for merchant ships, fuelled in part by China and
in part by the boom in large cruise ships. “Cruise ships
represent a fifth of our volume but 60 percent of value,”
says Cappellari.
Cruise ships are different from other vessels in dry dock.
Their energy requirements are huge because the crew stays
on board during maintenance. “The energy for one cruise
ship equals the energy needs for a city of 40,000 inhabitants,”
says Nereo Pieri, shipyard manager.
To save money for ship owners, ATSM makes it possible for
ships in dry dock to generate their own energy supply, just as
they do on the open sea. However, the original pumps for the
dry dock built in 1984 were not flexible enough for the needs
of today’s large cruise ships, which require that the pumping
process in dry dock stops around the halfway mark so that
refrigeration units can be attached to the cruise ship to supply
the water for cooling the energy generators.
“We substituted the original vertical long-shaft pumps
with Flygt submersible pumps,” says Pieri. “These pumps
are more flexible, maintenance costs are lower, and they are
easier to service.”
Flygt pumps have performed so well that ATSM has chosen
them to replace other original pumps in the Trieste facility. ¶
A NEWS MAGAZINE FROM IT T FLYGT
The Italian port of Trieste lies close to the border
with Slovenia.
Wet pumps
Three different kinds of pumps are needed in dry docks, says
Alfredo Zoratti, head of Flygt’s office in Udine. The most
powerful are the main pumps used to drain most of the water
from the dry dock. They can drain 12 metres in four hours.
The auxiliary pumps are used to remove the final two metres
of water from the dry dock. And the drainage pumps keep the
dry dock free of water in case of rain or water leakage.
Flygt submersible pumps offered three advantages over the
existing vertical pumps in use, Zoratti says.
• Flygt submersibles are lighter and more compact, therefore
easier to install than traditional pumps.
• Flygt pumps are faster and easier to service, with less down
time for the client.
• Flygt offers technical assistance pre- and post-sale – a
significant factor in ATSM’s evaluation.
There are currently two Flygt PL 7081/735 pumps, one
CP 3201 HT, two CP 3400/735, two CT 3201 HT, and one
3085.181 in use at ATSM.
Impeller 13
My opinion
¶
Efthimios E Mitropoulos is secretary general of the International Maritime Organisation. Mitropoulos, who once
served as harbour master of Corfu, comes from a maritime family in Greece. He has been with the IMO since
1979, and is the author of several books on shipping economics and policies.
PHOTO IMO / MÅRTEN JOHNÉR, JOHNÉR BILDBYRÅ
Keeping a clean ship
he oceans are among our most
precious resources, playing a key
role in climate and weather patterns and providing food resources and
employment, including tourism. As the
United Nations agency charged with responsibility for the safety and
security of shipping and the
prevention of marine pollution
from ships, the International
Maritime Organization (IMO)
includes in its objectives the
concept of “clean oceans,” balancing this with the legitimate
use of the seas.
One of the most important
of IMO’s international treaties
is the International Convention
for the Prevention of Pollution
from Ships, 1973 (modified in
1978), which includes regulations regarding the prevention
of pollution in six areas: oil, chemicals
carried in bulk, goods in packaged form,
sewage, garbage and emissions from
ship exhausts.
Regulations regarding sewage have
been adopted to address the fact that
the discharge of raw sewage into the sea
from ships can create a health hazard. In
coastal areas, sewage can lead to oxygen
depletion and obvious visual pollution
– a major problem for tourist destinations. The main sources of humanproduced sewage are land-based, but all
T
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ships have people on board who create
waste. The development of the cruise
industry, with ships built to carry the
population of a small town, has led to an
increased need for the implementation
of sewage regulations, to ensure that
pristine coastal areas remain that way.
The regulations regarding sewage
entered into force in September 2003.
Revised regulations were adopted in
April 2004, with the new regulations in
force as of 1 August 2005. The regulations will apply to new ships of 400 gross
tonnes and above on international
voyages or ships that are certified to carry
more than 15 persons. Existing ships will
need to comply from August 2010.
Under the revised regulations, the
discharge of sewage into the sea is
prohibited, except when the ship has in
operation an approved sewage treatment
plant or is discharging broken down and
disinfected sewage using an approved
system at a distance of more than three
nautical miles from the nearest land,
or when the ship is discharging sewage that is not broken
down or disinfected at a distance of more than 12 nautical
miles from the nearest land.
Governments are required to
ensure the provision of facilities at ports and terminals for
the reception of sewage.
The implementation of
these rules is crucial in ensuring that ships do not contribute to pollution of coastlines
with sewage. This is a matter
of keen interest and should
also be a matter of serious
concern to all of us if we are to preserve
the marine environment for future
generations. ¶
Efthimios E Mitropoulos
secretary general of the
International Maritime Organisation
Impeller 11
¶ Profile
Naval architect Stephen Payne is a man of simple tastes and grand visions. One of these
visions, the Queen Mary 2, is now plying the seas between Southampton and New York City.
n 1972, a 12-year-old boy, already gripped by the beauty
and romance of ocean-going liners, watched in horror as his
favourite TV programme, known to millions in the UK
as Blue Peter, broke off from its normal schedule and switched
to Hong Kong harbour where the old Queen Elizabeth ship
was ablaze. “There will never be another passenger ship to
rival her,” said a solemn voice. Indignant, the boy wrote a letter to the programme’s editor, claiming that he’d show them
I
14 Impeller
otherwise. He received a blue badge as a consolation present.
Flip forward 31 years to January 2004, and that same programme was asked to bring its cameras on board the biggest
passenger ship in the world and the final word in luxury: the
Queen Mary 2. The invitation came from the man who had
designed the ship, naval architect Stephen Payne. “This time,
they gave me a gold badge,” he says with quiet pride.
Payne is a vice president of Carnival, the biggest cruise
A NE W S M AG A ZINE F RO M IT T F LYGT
NAVAL
GAZING
TEXT ALEX GAMES ILLUSTRATION SALGOOD SAM
company in the world. In 1998, Carnival bought Cunard, the
passenger ship line that owned the Queen Elizabeth and her
sister ship, the original Queen Mary, which has been permanently docked in Long Beach, California, since 1967.
Showy is not the word to describe Stephen Payne. His office is
barely three deck-chairs wide, with a sprinkling of trophies
above a bookcase and some framed photographs of various
A NEWS MAGAZINE FROM IT T FLYGT
liners and cruisers. His main trophy is out there on the water,
plying the six-day journey between Southampton and New
York. “Each time she comes back, I look out through the window and think, ‘There’s my baby,’” he says.
Payne’s team delivered the ship on time and within budget
after less than two years of construction. Uninterested in
complex theories of management practice, he built team spirit
with Chantiers de l’Atlantique, the Alstom-owned French
Impeller 15
¶ Profile
PHOTO MAGNUS FOND / JOHNÉR BILDBYRÅ
“Each time she comes back,
I look out through the window
and think, ‘There’s my baby.’”
shipyard that built the QM2, by inviting the principals from
the QM2 project team, headed by Jean-Remy Village, back
to his house for drinks and a barbecue. “They said no ship
owner had ever done that before,” he says. But at a price tag of
550 million British pounds and with the safety of 2,620 passengers as well as a crew of 1,253 at stake, the consequences of
misunderstandings or lack of trust were unthinkable.
There is more to Payne’s world than the Queen Mary 2,
though it would be fair to say that he wouldn’t last long in a
world without large bodies of water. He has no car (a rarity in
car-mad Britain), preferring to ride a Honda VFR800 motorbike. He enjoys giving slide-show presentations and lectures
aboard cruise ships, and he is a freeman of the Worshipful
Company of Shipwrights, one of the City of London’s trade
guilds, which was first recognised in 1515 but is a relative newcomer alongside guilds such as the Apothecaries, the Cordwainers and the Girdlers. Payne is also a Fellow of the Royal
Institution of Naval Architects, which was formed in 1860,
and he therefore follows in the footsteps of those members
who were responsible for the design of many of the great
trans-Atlantic liners of the past.
QE2. “She had to get through about 110 people that day, so
I only had about 30 seconds with her, but she was friendly,”
he says.
The pleasures of the QM2, as designed by Stephen Payne,
are manifold, but he doesn’t seem the type to exploit most of
them. He likes modern swing music but doesn’t go dancing
and avoids the theatre, cinema and fancy restaurants. Not a
football or gambling man, he enjoys making model ships in his
spare hours. He is also an enthusiastic home cook and is particularly fond of his chilli-flavoured ice cream.
Payne is in the great tradition of British enthusiasts, and
there are times, as he speaks, when, apart from the suit and tie
(embroidered, of course, with the profile of the SS Lusitania)
he could, once again, be that 12-year-old boy, writing in high
dudgeon to his favourite TV programme. “On 25 September
1967, the old Queen Mary and the Queen Elizabeth crossed in
New York harbour,” he says. “At the time, everyone said that
never again would there be two Cunard queens. Well, there
are now.” ¶
Payne also sports a modest lapel badge, which on closer in-
spection turns out to be a badge for an Officer of the Order of
the British Empire or OBE, an honour that he collected in 2004
from Queen Elizabeth II who had, of course, christened the
Getting personal
16 Impeller
Favourite city: Edinburgh.
Musical pick: Rimsky Korsakov’s
Scheherazade.
Top dish: Lamb tajine.
Clothes store: Marks & Spencer.
Hero: Engineer and bridge-builder Isambard
Kingdom Brunel (1806-1859).
PHOTO EVA EDSJÖ
Stephen Payne
Born: Lewisham in southeast London,
1960.
Educated: Catford School for Boys and
Southampton University (studying naval
science).
Favourite harbour: Corsica.
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Wyong Shire lies 100 kilometres north of Sydney.
Preserving beauty
A beautiful part of Australia’s southeastern coastline has been experiencing
a massive population explosion. To cope with the increase, the local sewage
treatment plant underwent a radical overhaul, using innovative solutions to
deal with aging equipment and noise pollution.
TEXT DUNCAN CRAIG PHOTO PATRICK CUMMINS ILLUSTRATION ANN-SOFI MARMINGE
he Wyong Shire district of Australia, situated 100 kilometres north of Sydney, has undergone a dramatic
increase in population in the past decade, as city folk
increasingly have left behind the stresses of the bustling city
to enjoy the region’s stunning coastline, warm climate and
rugged mountains and parklands.
The area is rich in native bird life, with more than 100 native
species of birds, including the famous yellow-crested black
cockatoo. It is also a popular fishing and boating spot, as it
encompasses a maze of waterways and lakes that feed into the
ocean. All around the district suburban enclaves are springing up. In Australia, this trend is known as “the sea change.”
“The population has exploded here in the past 10 years
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because people have moved here to enjoy the lifestyle benefits
of the Wyong area,” says Bruce Pountney, who has worked as
the operator in charge at the Wyong sewage plant for 14 years.
“A lot of people like to live by the seaside in Australia because
we are a water-sports nation.”
The scenic beauty of the area means there is also an influx of
holiday-makers over the summer period, which puts further
strain on the region’s infrastructure.
Indeed, the population of Wyong Shire is forecast to swell
from 140,000 to 200,000 during the next 15 years as more
blocks of land are released for housing development.
With the increase in population, the Wyong Shire Council
Impeller 17
became concerned that the local sewage plant, situated behind
a clad of bush less than 200 metres from the main road into
the Wyong township, could turn into an environmental hazard.
The plant had installed surface aerators that were noisy and
ran the risk of local workers being exposed to potentially
harmful aerosols. The volume of sewage required for treatment had risen dramatically in the past four years, and the
council was facing the burden of having to invest in more
aerators and pumps.
“The existing process was inefficient, and overall the plant
was generally unreliable,” says Stephen Sherwood, a eastern
region manager for ITT Flygt in Australia who was called
in to help fix problems at the sewage plant. “However the
council was simply putting up with what they had without
realising there was a reliable and cost-effective solution in the
provision of new submerged systems.”
Once the sewage is treated at the plant, it is dispatched to a
polishing lagoon and then pumped out through an 18-kilometre
pipe into the ocean.
“I went into the local shire office and told them the existing mechanical aerators were blowing up the gearboxes,”
Pountney recalls. “The equipment wasn’t doing the job, and
we ran the risk of effluent that wasn’t being treated properly
going out into the environment.” Indeed, in the summer
of 2000, a failure of two surface aerators in one of the tanks
caused a breakdown of the biological treatment process.
The situation was becoming urgent, so the council decided to
install ITT Flygt’s new jet aerators equipped with N-pumps,
which, since they lie beneath the surface of the effluent, produce no noise or spray. Sherwood managed to get 12 sets of jet
aerators equipped with N-pumps delivered in eight weeks.
“The equipment wasn’t doing
the job, and we ran the risk
of effluent that wasn’t being
treated properly going out into
the environment.”
The noise levels have now been reduced. There are only
a few surface aerators remaining on the site, and power consumption costs have fallen.
Nature lovers in the area are delighted because there is a
tower adjacent to the site where people come to spot the rich
variety of local birds.
Sherwood says he was recognised for his ability to cement
a strong relationship with the local council and for delivering a low-cost solution that assisted the council in heading
off a potentially embarrassing environmental problem. The
Wyong Council is now planning to install more jet aerators
with N-pumps in additional tanks and is gradually ripping
out all of the remaining surface aerators.
As for Sherwood, a keen outdoor enthusiast, he was simply
happy to solve a potential problem for the local council and
the wider community. ¶
Fast turnaround
The deployment of Flygt jet aerators
equipped with N 3300 pumps have
provided immediate benefits to a
sewage treatment plant situated in
the fast-growing southeastern coastal
region of Australia. As part of a
revamping of its biological treatment
process, the plant switched from
surface aerators to a submerged
system, which in turn have reduced
the risk of clogging, provided silent
operation at the plant and reduced
ongoing maintenance costs. The
submerged Jet aerators have also
improved oxygen transfer rates and
reduced power consumption costs.
In addition, they are proving more
reliable than the previous surface
aeration system.
18 Impeller
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¶
On the surface
PHOTO F. ESPINASSE
Valuables on board
The Airbus 380, the largest commercial airplane to fly the skies, is being built in several
European facilities and assembled in Toulouse, France. This is a logistical challenge,
as the largest parts of the plane must be delivered in a timely and safe fashion across
seas and countries.
During one of the final stages of the journey – from Airbus plants in the United
Kingdom and Germany – the wings, the tail and fuselage sections are carried by barge
on the Garonne River that runs through southwest France.
These giant parts are unloaded at the Port of Langon after the barge has entered
an elevator basin that levels it with the dock. To fill the elevator basin, three Flygt
PL 7061 pumps were installed at this facility. Depending on the tidal level of the river,
the pumps need between 20 and 105 minutes to raise the water to level the dock at
a pace of three cubic metres per second.
The elevator basin has already been used to transfer parts of the first A380 that will
be exhaustively tested before the model enters into regular production. At that stage,
there will be four deliveries of airplane parts a week at the port of Langon, 200 kilometres from Toulouse.
¶
Staying afloat
in Finland
The 155-metre-long Global Freighter carrying
about 50 trucks and trailers, ran aground
not far from the Finnish harbour of Turku in
the Baltic Sea in September 2004. The hull
was severely damaged and water poured in
through several holes. The captain directed
the ship immediately into shallow waters to
avoid sinking. No one onboard was injured
and a quick oil-spill prevention effort proved
to be unnecessary.
But the freighter couldn’t be moved from
its position without danger of capsizing.
Meanwhile the damage was too great for
repairs on site.
Three powerful ITT Flygt pumps, a 2151 LT
and two N3152 MT pumps, and a power
unit together helped solve the problem. The
pumps were able to remove the water (that
was coming in at a rate 300 l/s) while the
freighter was towed to a dockyard.
Reliability was crucial for this operation
since the boat could capsize if the pumping
stopped. But over the course of the 100-hour
operation, the pumps performed their duty,
and the ship was manoeuvred safely into the
dockyard.
¶
Water harvesting
The Stockholm Water Prize 2005 has been awarded to the Centre for Science and Environment (CSE). The CSE is a non-profit
environmental organisation headed by Sunita Narain, an advocate
for water, environment, human rights, democracy and health.
The prize given to CSE under Sunita Narain’s leadership cites
the need for new approaches to solve the food and water management problems of many poor areas.
“It’s wonderful to receive the prize,” said Sunita Narain at the
prize announcement in March. “Unclean water is still the most
common cause of death among children worldwide. The prize will
be a strong support for us in
our work with future water
maintenance.”
The Stockholm Water
Foundation has sponsored
the annual prize, worth USD
150,000. The winners receive
their USD 150,000 awards
from the Swedish king during
a prize ceremony held on
August 25 during World Water
Week in Stockholm.
PHOTO SIWI
¶
FROZEN DIAMONDS
The Diavik diamond mine
is situated on a small island
in Lac de Gras, a large lake
in Canada’s Northwest Territories, 220 kilometres south
of the Arctic Circle and
some 100 kilometres from
the closest village. It is an
off-shore open-pit mine
that relies on water-retention dikes to temporarily
hold back the surrounding lake water, allowing mining to be
carried out on the lake bottom.
ITT Flygt Canada was engaged in the building of the first of
three projected dikes, by supplying a number of prefabricated
fiberglass stations, pumps and peripheral equipment for a
seepage collection system. The contract included the supply of
12 CP3300 pumps. Ten have been installed in five Flygt GRP
stations (approximately 4 metres in diameter and 8 metres
long) and two have been kept as spares. Five Flygt Monitor and
Control system controllers are used for automatic control of the
stations. The total installed capacity amounts to 440 l/s.
This project has allowed ITT Flygt to show to the industry
a new way of installing pumps in a permafrost region, using
special arrangements to protect the equipment.
PHOTO GETTY IMAGES
takes the prize
¶
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Impeller 19
¶ Watertight
GREAT HEROES
in a small format
Durable, reliable and easy to use and to maintain. Flygt’s new Ready
pumps are in a class of their own in the submersible pumps segment.
TEXT ERICO OLLER WESTERBERG PHOTO JOAKIM FOLKE
20 Impeller
A NE W S M AG A ZINE F RO M IT T F LYGT
ales staff have a favourite trick.
They pretend to “drop” a Ready
pump on the ground in front of
their clients. Depending on which side
it lands, the pump either bounces or
lands with a thud. But it never breaks.
The smallest of the Flygt pumps, the
Ready pump has been built to withstand
a great deal, and thus it is in a class of
its own in this particular market segment.
The material used not only guarantees
that the pump can literally be thrown
onto the platform of a truck, but it can
also withstand the impact of solid
particles and certain aggressive substances
found in the water.
“Ready pumps are universal, a tool that
is always ready,” says Helena Roxtorp,
from Flygt’s business unit Construction
and Mining, who is responsible for the
launch of the new upgraded Ready
pump range.
“They are fast and easy to use,” she
says. “Ready pumps can drain cable
manholes, flooded buildings or waterlogged building sites. And you do not
have to worry about tough handling,
clogging or damaged hydraulic parts.
“In other words, they are high-quality
pumps with smaller dimensions for the
professional user.”
S
The range is not new, but the pumps
have been upgraded and improved,
and a brand new model has also been
introduced. The purpose of the product
development was to meet market demands, and the process has resulted in
major improvements. The new pumps
are easier to use and to maintain.
Their performance and durability
present the exceptional standard that
has been part of the pump range from
the beginning.
“The plug-in cable is a much appreciated improvement,” says Roxtorp. “It
is a pin connection that facilitates the
change of cables. In fact the cable often
takes the worst when, for example, it
is blocked or driven over. It is now so
much easier to replace. It only takes a
matter of seconds.”
Other improvements that have been
made are:
• An inner cover in stainless steel, which
ensures the dry running of the pump
for extended periods as well as heatresistance.
• A two-position outlet, which reduces
the risk of a blocked hose.
A NEWS MAGAZINE FROM IT T FLYGT
“Ready pumps are universal,
a tool that is always ready.”
• A more powerful handle with an
improved ergonomic design.
Ready pumps do not contain cast-iron
components. They are made from stainless sheet metal and composites, which
makes them light and portable. The
impeller is made from polyurethane and
is very hard-wearing, and the whole
construction can withstand acids. Thus
the pumps can be used in environments
with a pH-value of between 3 and 9.
The three models in the range have a capa-
“A Ready pump is not suitable for
continuous operation over several weeks
– other pumps are more suitable for this
purpose,” says Roxtorp. “A Ready pump
is normally employed for intermittent
use and often when time is short. It is a
handy pump and the only thing the user
should have to do is to plug it in.”
Ready pumps can be equipped with a
level regulator facilitating an automatic
shut-off at the required water level and
a low suction collar, which enables it to
reach very low water levels. ¶
city of between 4 and 7 l/s and a maximum head of between 9 and 15 metres.
This type of pump is ideal in repairing
service cars used by electricity and
telephone companies, rescue services
and the fire brigade as well as individual
craftsmen with a recurrent need for small
drainage pumps. Ready pumps can also
be used as a stand-by for emergencies in
industrial facilities, and they form part
of the range at tool hire companies.
ITT Flygt’s Helena Roxtorp and
Francisco García are responsible for the
launch of the new Ready 8S pumps.
Ready to face tougher challenges
Ready 8S (S as in Solids Handling
Pump) is the latest model of Flygt’s
Ready pump. The pump is designed
for handling water with larger solid
particles.
For this purpose a vortex impeller is
used and the pump casing has been
redesigned so that it can let through
and discharge solid particles of up to
38 millimetres. In contrast to its sister
pumps, the outlet is placed near the
impeller to reduce the risk of clogging.
“We realised that there was demand
for a smaller pump that was able to
operate in an environment with liquids
containing more solids. With its larger
throughlet and powerful motor, the
Ready 8S can, for example, handle
water with a high ash or foliage content,
which no other pump in the same
category can match,” says Helena
Roxtorp, who is responsible for the
launch of Flygt’s upgraded Ready
pump programme.
50 Hz/60 Hz
Ready 4
Ready 8
Ready 8S
Flow
3.8 l/s /60 usgpm
6 l/s /80 usgpm
6.3 l/s /100 usgpm
Head
10 m / 35 ft
14 m /50 ft
12 m / 35 ft
Power
0.45 kW /0.6 hp
0.8 kW /1.1 hp
0.9 kW /1.1 hp
Weight
10 kg /22 lbs
12.5 kg /27 lbs
15 kg / 33 lbs
Throughlet
5 mm / 3/16”
5 mm / 3/16”
38 mm /1½”
Impeller 21
¶ Watertight
SEAWATER IS
no obstacle
Well-designed protection, positioning and materials neutralise the
threat that seawater can pose to submersible pumps. It is possible
to avoid corrosion without costly and complicated solutions.
Ulf Backmark
22 Impeller
TEXT ERICO OLLER WESTERBERG PHOTO ITT FLYGT
A NE W S M AG A ZINE F RO M IT T F LYGT
n seawater different materials corrode
at different rates. In fact, a pump
placed in seawater can, in the worstcase scenario, corrode and disintegrate
within a matter of days. This can happen
if an unprotected aluminium pump is
placed next to iron structures, such as
piles at a construction site.
The reason for this rapid disintegration
is that such a pump becomes a sacrificial
anode that corrodes and disintegrates in
order to protect the more “noble” iron
found in the vicinity. The interaction
between the different metals is as
harmful as the salt in the seawater.
“Zinc anodes mounted on the pump
and placed a few metres away from the
nearest iron structure protect the
aluminium pump,” says Ulf Backmark
from ITT Flygt research and development. “The industry’s knowledge has
increased considerably, and fortunately
the number of pumps that fail due to
incorrect positioning has been reduced.
The correct positioning, correct material
and above all the correct protection
ensure a problem-free use of pumps in
seawater applications.”
Submersible pumps come into contact
with seawater in a number of different
applications – commonly at construction
sites close to shorelines where seawater
leakage occurs or on oil rigs, ships, fish
farms and at desalination plants.
I
In some niche applications pumps made
of stainless steel or bronze are preferred.
Both materials offer a high degree of
corrosion resistance, but the manufacturing
process is so demanding that these pump
models are few in number and expensive.
And even stainless pumps usually require
some form of corrosion protection in
seawater. Flygt, which has a number of
stainless pumps in its range, consequently
recommends cast-iron pumps protected
with zinc anodes and an epoxy coating.
“A cast-iron pump prepared for seawater applications offers practically the
same corrosion resistance as pumps made
of the more expensive materials,” says
Backmark. “Yet the fact that it is cheaper
to buy is not the only advantage. Equally
important for a cost-effective solution is
that clients can choose any pump from
the entire Flygt range, which means
that the best solution is guaranteed.”
also exposed to corrosion,” Backmark
continues. “The effect of galvanic
corrosion on cast-iron pumps from
stainless bolts and screws is prevented
by the effect of the zinc anodes.”
Furthermore, an advanced surface
protection is vital to minimise the
consumption of the zinc anodes, and it
gives them a longer operating life. The
protective current generated by the
“The days when seawater applications
required very expensive pumps or costly
and repeated maintenance are over.”
Owing to its salt content, seawater is an
excellent conductor of electricity. This
accelerates the corrosion process in seawater, as compared to freshwater. Typical corrosion that occurs in seawater is
galvanic corrosion, which sets in when
galvanic contact is formed between different metals placed in the same liquid.
“Fortunately, the same process can
be applied to protect pumps in seawater
by connecting a sacrificial anode, for
example, made of zinc, to the pump,”
says Backmark. “In that case, the corrosion
will attack the zinc while the pump
remains unharmed. Anodes of pure
zinc in different shapes are attached in
appropriate places to protect the pump.”
The size and useful life of the anodes
are calculated in advance. In normal
circumstances the anodes only need to
be replaced when the pump undergoes
a scheduled servicing or even at less
frequent intervals.
“The zinc anodes not only protect the
pump but they also protect its fastening
device and nearby equipment, which are
anodes only needs to address the
unprotected parts, where, for example,
the coating is damaged.
That is why ITT Flygt prepares its
cast-iron pumps for seawater applications
with great care. In order to remove all
contamination, the pumps are cleaned
thoroughly and then blasted just before
a layer of zinc-enriched paint is applied.
It is followed by three layers of the epoxy
coating, which are applied in order to
provide the entire pump surface with
effective protection.
Shaft seals made from corrosionresistant hard metals protect the electrical
motor in standard pumps. For extreme
applications, these seals are available in
silicon carbide.
If appropriate measures are taken for
seawater, the initial costs and service intervals don’t differ noticeably from solutions for less demanding environments.
“The days when seawater applications
required very expensive pumps or
costly and repeated maintenance are
over,” says Ulf Backmark. ¶
Protection of aluminium pumps
Submersible aluminium pumps from Flygt’s Bibo range are often indispensable at
construction sites and in mines. They are considerably lighter than cast-iron
pumps and therefore much easier to transport and put to work.
However, aluminium is sensitive to salt water and is not recommended for
continuous operation or permanent installations in this medium.
“Bibo pumps are, despite these limitations, ideal for temporary salt water use,
for example on construction sites where seawater leakage occurs,” says Ulf
Backmark from ITT Flygt R&D. “It is of vital importance that pumps are not used
near iron structures and that they are adequately protected with zinc anodes.”
A NEWS MAGAZINE FROM IT T FLYGT
Submersible Bibo
pumps gain added
protection from
seawater when
used together with
zinc anodes.
Impeller 23