international
construction
november 2014
PUMPS
50
Primed for action
>
in critical situations. In order to get their
job done, they need fast and reliable
dewateringfirst and foremost.
“The PAS combines high performance
with minimum operating expense.
For rental companies and dewatering
contractors, this is extremely important
as it enables them to get a faster return
on equipment acquisition costs, which
is exactly what they require to stay
competitive.”
The PAS 4, PAS 6 and PAS 8 have an
operating flow range of 50 to 600m
3
per
hour, with a maximum head of 37 m.
Their solids handling capacity reaches
up to 76 mm, and they feature an
environmentally-friendly, oil-free vacuumpumppriming system,
whichAtlasCopco said automatically removes air from thewater,
and ensures uninterrupted, unsupervisedoperation.
Mr Cantuba added, “We have selected good components.
“This includes a Kubota engine, which he said delivered high
performance at full loadoperation.
He explained that Kubota was perceived as a good quality
M
easuring 6 km the SEK 16.3 billion (US$ 2.23 billion) StockholmCity Line route is a
new double track commuter railway beneath the Swedish capital’s central district,
consisting of amain tunnel, and a further immersed tunnel at Riddarfjärden known
as Söderströmstunneln, and three commuter stations.
Themain immersed tube tunnel is 400m long, placed on four groups of piles at amaximum
of 24m below thewater’s surface. Each individual tunnel elementmeasures 100m long, 20
mwide and 9m high, andweighsmore than 20,000 tonnes.
For the placement of the tunnel on the pile foundation inRiddarfjärden, each element was
built with three internal ballast tanks, one slightly off-centre in each end, and one off-centre
in the opposite direction at the longitudinal middle of the tunnel element.
A total of 13 pumps have been used in the three tunnel elements for the project, connected
to a control-panel located on the immersion-pontoons usedwithin the project.
In order to control total water level, sink speed of the tunnel element and tomovewater
between the three tanks to control roll and tilt of the tunnel element, twomain pumpswere
placed inside each tank.
To handle leakage, twoMinex pumpswere placed outside each tank, and to control
bulkhead leakage a further two unitswere placed at the end of each tunnel.
Immersed installation
Grindex pumps help sink Stockholm tunnel segments
engine, but was seen by some as being
expensive. The marketing manager
claimed that other companies had found
they had to compromise performance to
increase efficiency, “but that is where we
canbring value to themarket”.
He said, “Efficiency is as important as
performance. What we do now is have a
wide range of engine speeds so that the
optimal speed canbe selected.
Mr Rehn added. “It’s performance first,
and efficiency immediately after that.
Reliability is the key thing.”
Mr Cantuba said, “High performance
will lead to high productivity, because if
it runs for a long timewithout unexpected
failures, it will finish the dewatering job faster. Pumps are
machines to solve problems, so theymust perform.”
He said Atlas Copco had the manufacturing competence.
“Other companies know what to do, but don’t have the ability
to do it on a large scale.Withdiesel-drivenpumps,most – if not
all – strugglewith the exhaust emissions regulations.”
The company’s experience with producing generators has
helped, with Mr Cantuba pointing out that a generator and a
pump are basically very similar animals.
Compact pumps
With this experience, Atlas Copco said it was also able tomake
compact pumps with advantages for transporting them and for
storage, which it claimed were simplified by the compact and
robust canopy, forklift slots and lifting eye.
JapanesepumpmanufacturerTsurumi has introducedanumber
of drainagemodels to themarket this year, including a new level
sensor KTZE pump, as well as two sand pumps – theGPN415,
with a 15kWmotor, andGPN622 , with a 22kWmotor.
The new drainage KTZE pump is based onTsurumi’s existing
KTZ range, which the company saidwas tested and proven as a
result of several heavy-duty applications.
Atlas Copco’s
Abet Cantuba,
“Our ambition
is to be among
the leaders in
dewatering
pumps.”
Tsurumi’s new drainage KTZE pump is based on
Tsurumi’s existing KTZ range.
