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PRODUCT News
August 2016
MODERN MINING
73
With the volatility of commodity prices today,
it is critical that mines are able to optimise the
operating costs of the entire plant, and this
need has seen an increased focus on achiev-
ing the desired grind efficiency in mills.
While each mill liner profile is designed to
provide the correct trajectory to achieve either
impact grinding or attrition grinding depend-
ing on the specific application, wear on the
mill liner profile will affect the grind efficiency.
Matthew Fitzsimons, Technical Manager
of Multotec Rubber, explains that it is impor-
tant to understand that the wear rate of liners
is not linear and that, as the liners wear, the
increased slippage of the charge increases the
wear on the liners.
“This can, in turn, rapidly decrease the grind
efficiency of the mill due to the trajectory in
the mill being sub-optimal and the energy
transfer for breakage is reduced,” he says.
It is for this reason that condition moni-
toring of mill liners, whether steel or rubber,
is necessary. Regular inspection of the liner
profile will allow historical data to be collated
which will facilitate liner life predictions.
Describing how liner inspection has been
done traditionally, Fitzsimons says that until
recently there have only been two options
available, one of which is the pin gauge
method which is known to be time con-
suming and often inaccurate. Furthermore
it requires that the mill be stopped to allow
access for personnel to actually perform the
inspection. At the other of the scale is very
expensive sophisticated technology.
Fitzsimons confirms that Multotec Rubber
recently introduced what he says is set to
become the most affordable best practice
mill liner profile condition monitoring system
because it offers high accuracy and immediate
availability of information at a reasonable cost.
“With the introduction of MultoScan, it is
now possible for plants to accurately measure
the liner profile and, using this information,
end users can easily and accurately predict
the lifespan of the liner and the point at which
the mill will become inefficient,” he says. The
automatic measurement and display of the
charge level is valuable in confirming that the
operation of the mill is correct and this value
is essential in calculating the trajectory.
Highly skilled technicians take the
data acquired by MultoScan and leverage
Multotec’s Hawkeye proprietary programme
to interpret and analyse the data.
Significantly there is no time lag on the
information analysis and the level of
responsiveness possible using MultoScan
has not been available to plants until now.
“It will allow customers immediate
feedback on the condition of the lin-
ers and any immediate issues can be
addressed on the spot,” Fitzsimons says.
Fitzsimons explains that MultoScan
has been proven in field trials in some of
the most arduous milling conditions on
the African continent.
Multotec Group, tel (+27 11) 923-6193
Affordable mill liner monitoring system
Multotec personnel discussing captured MultoScan
wear profiling data on tablet.