February 2014
MODERN MINING
51
PRODUCT News
While many South African plants are
still running on Warman AH® series
slurry pumps for highly abrasive
mill duties, an increasing number
of plant operators in other parts of
Africa are reportedly recognising
that the latest generation Warman
MCR® rubber-lined centrifugal slurry
pump from Weir Minerals Africa
offers superior safety and low own-
ership costs, as well as outstanding
performance and reliability.
“These pumps are recording
major successes globally across a
broad range of commodities and in
Africa we’re looking at a number of
additional new MCR pumps going
into operation this year alone, so this technol-
ogy is clearly generating a substantial amount
of market confidence,”says Rui Gomes, Product
Manager: Slurry Pumps atWeir Minerals Africa.
“The MCR pump is specifically designed for
mill discharge and cyclone feed duties, incor-
porating a number of elements that maximise
performance in the most aggressive wear
applications. Features such as impeller design,
liner material, specific speed and bearing
assembly allow the pump to easily manage
large size particles in dense abrasive slurries
and offer the right combination of ruggedness,
durability, hydraulics and materials.
“A big advantage is the full front throat bush
adjustment that helps with pump efficiency
and performance and is critical to the efficient
operation of the pump, while a quick-change
feature allows technicians to replace the wet
end of the pump on site.”
One of the most outstandingWarman® MCR
case studies was recently documented at a
gold mine in south-western Ghana, where a
trial installation was initiated to match the per-
formance and wear life of an existing Warman
14/12 AH metal pump and a competitor’s
16/14 primary mill discharge pump. The trial
also sought to determine whether a Warman
350 MCR could handle the mill’s tonnage.
“The initial milestone of matching or
improving on the 2 100 t/h achieved by the
original pumps was quickly achieved,” Gomes
says.“The second and more critical goal was to
increase the wear life of the pumps and here
the target of 1 000 hours of operation without
failure was also achieved. The impeller lasted
about 1 900 hours before requiring replace-
ment and the R55 rubber liners continued
without needing replacement.
“A number of factors drove the success of
this trial. Firstly, the pump design was ideally
suited to the duty, compared to the pumps
previously installed – notably the contribution
of the MCR’s rubber lining to the substantial
increase in its wear life and the consequent
improved mill availability. We were actually
astounded at the performance of the rubber
liners versus the metal volute originally in
place. At the four-month inspection there was
still a substantial amount of residual value on
the liners and we estimate getting to about
6 000 hours – six times as long as the life of the
metal volute.”
In another successful installation in theWest
African gold industry, a Warman 350 MCR
was installed to compare against a Warman
16/14 AH metal pump. The mill was operating
at flows of about 2 000 m
3
per hour to a head
of 38 m and the Weir Minerals Africa team had
to install the MCR to fit in with existing pipe-
work and foundations. The complete wet end
was changed out after about 1 400 hours,
which more than doubled the life of the metal
volute of the 16/14, effectively improving plant
availability.
“This particular site was experiencing the
fairly common problem of mill balls coming
through the system and cracking the metal
volutes,” Gomes says. “However, the R55 rub-
ber liner offered an indirect, but immediate
solution to this operational issue. The cus-
tomer was also impressed by the quick and
easy adjustment capability, the reduced cost
of replacement spares and the improved safety
levels. This MCR was installed in 2012 and we’re
getting similar feedback after 18 months of
operation.”
Rene Calitz, Weir Minerals Africa, tel (+27 11) 929-2622
MCR® mill pumps prove themselves in Africa
The 200 MCR is one of six sizes of mill circuit pump that are fully
manufactured in South Africa by Weir Minerals Africa.
