hydraulik - HANSA-FLEX Hydraulics Canada Inc.

HYDRAULIKPRESSE
OIL SERVICE FOR THE EMS BARRIER
Everything shipshape for the magnificent „AIDAbella“
Preventative maintenance on the gateway to the North Sea
Papenburg since 1795 and now boasts the world’s
most modern shipbuilding facilities. Virtually the
entire manufacturing process has been digitised.
Using the so-called “Lego building block principle”
the shipyard not only produces cruise liners but
also special ships such as gas tankers, ships for the
transport of livestock and ferryboats.
The 250 metre or so long Aida Clubschiff carefully
inches its way through the Ems flood barrier. For
the cruise liner built at the Meyer Werft shipyard in
Papenburg, the Ems barrier is the final hurdle before
passing into the open waters of the North Sea.
The Ems barrier at Gandersum is one of the most
modern of its type in Europe and has been in operation
since September 2002. This structure, 476
metres in length, is operated by the Aurich branch
of the Lower Saxony Water Management, Coastal
Defence and Nature Conservation Agency (NLWKN).
Its key function is to protect the German coastline,
in particular from storm surges. If waters rise over
3.70 m above mean sea level (amsl), the gates of
the flood barrier will close off the hinterland, as
happened recently during the autumn storms last
November.
Construction of the storm surge barrier has done
away with the need for continuous adjustment of
the main dykes upstream along the Ems (towards
Papenburg) and its tributaries, something that
would be required every 30 or 40 years according
to experience.
The barrage function of this structure also contributes
to the economic performance of the entire
region by ensuring that the shipping channel
between Papenburg and Emden remains more or
less passable and permits the passage of ships built
at Papenburg’s Meyer Werft on the Ems with a top
water level of 2.70 metres amsl. The shipyard – one
of the biggest employers in the Emsland district
– has an outstanding international reputation for
building upmarket cruisers, with the largest measuring
up to 38 m in width and 300 m in length.
This traditional firm has been constructing ships at
To enable passage of such enormous ocean liners
from Meyer Werft to the open sea, the water
level of the Ems can be raised up to 2.70 metres
amsl. There should be no hitches in this process,
with three such occasions being planned for 2008:
everything is planned down to the finest detail.
Whenever a ship is due to pass through, the flood
barrier has to dam up the Ems to provide the agreed
depth of water on the date agreed. Water has to be
pumped behind the floor barrier depending on the
ship’s draught and the tide level of the Ems. This
task is performed by gigantic pumps with a total
power of 6,300 kW. The combined delivery rate of
the six pumps is some 100 cubic metres per second,
including with fluctuating tide water levels. Water
is taken in via the pump inlet located in the part of
the barrier facing the sea and closed off with steel
flood gates when the pumps are not in operation.
The pumps are installed in six piers, with water
flowing from two sides. They are driven with a
power output of 6,300 kW, forcing water into the
Ems out of pumping channels up to four metres in
width and 2.60 metres in height. The inlet cone,
the suction cone and above all the pump spiral
installed in the piers are prefabricated parts made
of high-grade concrete. The diameter of the impellers
range between 2.25 and 2.6 m. If one of these
pumps breaks down, the decisive inch of water may
be lacking that allows a ship to pass into the open
sea in the scheduled time slot.
A timely oil check
NLWKN therefore performs preventive maintenance
to ensure the availability of the pumps in
the flood barrier as any malfunction soon upsets
the programme for the passage of a ship along the
Ems. When Uwe Narten, the operations engineer
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HYDRAULIKPRESSE
ISSUE APRIL 2008