UNDERGROUND LOAD & HAUL
footprint. The others include an RDH-Scharf
electric scissor lift (the Liftmaster 600 EB), which
comes with operating costs 70% lower than the
diesel equivalent; two 100%-electric buses to
transport workers from Rancagua to the El
Teniente operations (at 3,100 m high); and a 100%-
electric bus link for urban use within Rancagua.
“Codelco’s electromobility strategy also
contemplates the incorporation of an electric bus
for the Chuquicamanta Division for the first half
of this year,” Codelco said in a statement
translated from Spanish to English. “In addition,
El Teniente will add three additional electric
buses during the year, a second LHD, this time
100% electric, and an electric mining truck for the
interior of the mine.”
IM spoke to Jim Callahan, Product Manager,
Underground Hard Rock Vehicles, Caterpillar and Randy
Schoepke, Commercial Manager, Underground
Technology, Caterpillar for their take on the market
Q In the past there has been a focus on production of larger tonnage
machines, but this has slowed down, with 60 to 65 t trucks and 20 to 22 t
LHDs being the top end: is the market limited by the fact that only a
relatively small number of mines are producing the tonnages required
and with the sizes of headings needed to make machines any larger than
this cost effective?
JC: Yes, truck and loader capacity growth has tended to stabilise at these
levels. But I would not be so bold as to suggest it will stop there. As a
starting point, geology, orebody characteristics and ore grades in
combination with broader mine economic considerations will in many
respects dictate equipment size. Ground conditions and the resulting cost
of ground support will be a factor tending to limit drive size. Additionally,
larger drive sizes can reduce advance rates. Also equipment flexibility for
mining contractors is a factor that comes into play when you consider that
there is a comparatively small number of operations pushing the
conventional tonnage limits. But looking more closely at the equipment,
when it comes to underground haulage economics, useable payload is
certainly a key criterion. For the OEMs, since we are all essentially
working with the same selection of available tyres, it becomes a matter of
packaging as much capability into the envelope as practical while
maintaining safety and balancing payload against performance and
durability of structures and components. While there are many alternative
haulage systems in use, conventional 4x4 two-axle articulated trucks
represent the bulk of the industry. Of course, adding a third or even fourth
axle is one way to increase payload within a given envelope; however,
consideration needs to be given to such factors as maneuverability,
flexibility, raised bed heights, and drivetrain complexity, which in turn can
impact maintenance cost and intensity. And then there is the question of
available powerplant selections for speed on grade.
Q What are contractors and your major underground dealers asking you
for today in terms of machine performance, development, product range
enhancement etc?
JC: I would distill it down to some common themes we hear from
contractors, miners and our dealers. An expectation of continued safety
enhancements is a given both in operation and maintenance. Then cost
per tonne gains by way of increased productivity and lower owning and
operating costs. Emissions solutions to meet the myriad regulations and
standards globally and an increasing desire for zero emissions solutions.
Cat semi-autonomous and autonomous technology solutions are
increasingly leveraged by our customers to make step changes in safety,
productivity and cost. We are being asked for and providing solutions
today along the spectrum of operator coaching, operator assistance as
well as automating portions of the cycle – right through to fully
10 International Mining | JUNE 2019
Octavio Araneda, a Vice President of
Operations for Codelco, said (also in Spanish to
English translation): “In the framework of our
Sustainability Master Plan, in Codelco we
execute a transition program to gradually
decarbonise the energy matrix of our operations.
“An edge of this initiative is our strategy of
electromobility that, after positively avoiding a
autonomous operations. Also generating increasingly more interest are
connectivity solutions, which facilitate the extraction of value from
onboard systems—either to optimise productivity or to ensure uptime
through activities such as condition monitoring and remote
troubleshooting. And customers are starting to realise the potential
productivity and safety benefits that come from underground positioning
systems for heavy equipment, light equipment and personnel.
Q Can you give me an update in terms of some project examples where
Cat is making real progress with autonomous fleets that have recently
been delivered or expanded?
RS: Caterpillar has been delivering semi-autonomous solutions since
2009 on underground loaders. As underground mining challenges
continue to drive costs and decrease productivity the need for automation
is growing. A gold mine in Eastern Canada has recently expanded their
fleet of autonomous loaders to include three machines equipped with
Caterpillar’s latest Command offering, which will allow fully autonomous
cycles as the new R1700 loaders have Auto Dig capability. Even though
the fully autonomous underground mine is the vision for the future, many
customers continue seeing value in semi-autonomous operations. A gold
mine in Nevada is currently expanding their semi-autonomous fleet with
Command retrofit solutions for their Caterpillar fleet of R1600Hs. The
retrofit solution allows them to upgrade existing assets, rather than
spend capital on new loaders, to take advantage of automation
technology. These are just two examples of a growing global footprint of
Caterpillar Command for underground solutions. While safety is often the
driver for the use of semi-autonomous or autonomous fleets, miners soon
realised that utilisation improvements of both the machine and operator
are providing the return on investment. Whether it is being able to access
areas of the mine that are too hazardous for traditional line-of-sight
remote control, or the ability to operate during gas venting after blasting,
remote operations deliver more tons. Caterpillar is also offering an
underground positioning system to support the autonomous mining
system and to further enhance safety underground.
Q Where is the crossover between battery load-and-haul underground
along with autonomy?
JC: We see that autonomous operation offers value to our customers
regardless of whether the source of power is an internal combustion
engine or a battery. It seems now that there is an opportunity to leverage
autonomy and/or equipment tracking and dispatching technology to
optimise the productivity of machines that have more frequent ‘refuelling’
needs such as battery electric machines. Both autonomy and
electrification will continue to change the underground mining industry.
The technology for these solutions is far advanced and will continue to
develop. Mining companies are now engaged in changing mine
infrastructure to allow them to implement these new technologies.