Global projects and exploration
options with the customer, after which our dewatering
and engineering teams collaborated closely to design a
solution. It was vital to carefully consider the problem
in the context of the geographic and site conditions, as
well as the local fauna and flora.”
To provide the most suitable Weir Minerals
products and solutions, the team specified a Warman
AH 10/8 pump mounted on a Multiflo pontoon,
with the pump coupled to a variable frequency drive
(VFD) facilitating greater flexibility in dealing with
varying site conditions. A second pontoon was fitted
with a Warman AH 6/4 pump with motor and fixed
speed drive, as design conditions should remain
constant throughout the life of mine.
Both pontoons are connected to a floating docking
station which is, in turn, connected to a 20m walkway
fixed to the bank-side landing.
“It is standard practice in most of our pontoon
designs to mount the pump sets at 30 degrees to
submerge the suction eye of the impeller, thereby
ensuring consistent priming,” Matthews says.
One of the most important factors affecting the
solution was Madagascar’s weather conditions, which
include regular tropical storms and high wind speeds.
These have the effect of creating wave action and
wind loading on the pond during storms, which the
pontoon solution has to accommodate.
To address the wave action and minimise possible
structural damage, the fixed walkway was designed
to incorporate a pivot system on the bank landing
structure. This allows the entire assembly, including
the docking station, to rotate 90 degrees and still be
tied down to the shore during these storms.
“Madagascar is also known for its varied wildlife,
including crocodiles,” says Matthews, “so the design of
Engineered-to-order Multiflo pontoons are commissioned at the
customer site.
Having the Warman slurry pump mounted onto the skid solves the
customer’s problem with continually collapsing suction hoses.
One of the two Multiflo pontoons during installation phase.
Pumps are mounted at 30 degrees to submerge the
suction eye of the impeller.
www.miningmirror.co.za
the handrails and other structures needed to prevent
crocodiles from gaining access to the deck space.”
These creatures would tend to climb onto the deck
to bask in the sun, making it almost impossible for
staff to conduct routine maintenance. Restricting this
access was achieved by closing all the gaps between the
handrails and the separate structures.
“Our design took all the site conditions into account,
making for better and more predictable operational
reliability,” he says. “Both the pontoons and the pumps
can now be easily moved for servicing or for securing
during bad weather.”
JANUARY 2019 MINING MIRROR
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