ELECTRONICS
B&R INDUSTRIAL
Reliable giants
THE COST OF ACHIEVING EXCAVATOR RELIABILITY CAN BE REDUCED
CONSIDERABLY THROUGH THE USE OF INTELLIGENT MAINTENANCE
monsters take huge bites out of the rocky
landscape. The world’s largest mining excavator is
24 meters long, 8.8 meters wide, 11 meters high
and weighs in at 800,000 kilograms. Seated
comfortably in the cab a dizzying 10 meters off
the ground, the driver works the joysticks that
control an enormous 47-cubic-meter bucket. In
just 20 seconds, the colossal machine moves 80
tons of material. “When such a huge excavator
goes down, not only does the operator suffer
costly losses in productivity, but the ramifications
can be felt throughout the entire logistics chain,”
says Stefan Taxer, B&R’s product manager for
mobile automation.
Preventing unexpected downtime is therefore
a top priority. To this end, rotating components
like hydraulic pumps, motors and gearboxes are
traditionally over-engineered or replaced at
conservatively short intervals. To keep any
downtime that does occur as brief as possible,
mining companies maintain a sizable stock of
replacement parts close at hand. “What all of
these solutions have in common is that they incur
additional costs,” says Taxer. These costs can be
reduced by applying modern approaches to
analytics and maintenance.
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Far from the nearest civilization, towering
high above their human masters, gigantic
iVT International Off-Highway 2020
Forecasting faults
As time takes its toll on rotating machine
components, even an untrained ear can often
hear the difference. “It’s relatively easy to tell
when your car has a defective wheel bearing
because of the distinct noise it makes,” says Taxer.
Mining excavators are so noisy, however, that it is
impossible to distinguish any audible change.
“This is where vibration-based condition
monitoring comes in handy.”
After all, the audible noise is nothing more
than vibrations at a certain frequency. A properly
configured condition monitoring system will
recognize a spike in vibration amplitude in a
specific frequency range as the signature of an
impending fault. The height of the spike denotes
the severity of the damage, indicating how soon a
given part should be replaced.
Putting vibration data good use
“Evaluating vibration data relies on two critical
elements,” says Taxer. On the one hand, you need
high-performance hardware that can read the
data at a sufficiently high frequency. On the other,
you need intelligent software able to detect the
tiniest deviations in a huge volume of data.
“Our modular X90 control and I/O system
offers the perfect hardware platform,” says Taxer.
The heart of the system is the X90 controller with
a powerful ARM processor and up to 48
multifunction I/O channels. The modular
controller can be equipped with optional I/Os,
ABOVE: B&R’s modular X90 control system
is available with an optional circuit board for
implementing condition monitoring. Vibration
sensors can be connected directly and their data
evaluated on the controller
LEFT: Vibration analysis data helps machine
operators identify the best time to replace specific
components