HIGH PROFILE
A new class of technology
In late October 2017, Paul Moore went with Liebherr to the
VA Erzberg iron ore mine in Austria for an introduction to
the new T 236 100 t diesel electric truck, and quizzed
Liebherr Mining senior managers on the technical
argument for the design as well as its market entry potential
iebherr last year launched the T 236, a new
100 t class truck in an already crowded
market, so it had to be a game changer in its
technology offering and performance upside. It
had already gone through an intensive product
validation phase at Erzberg. The tests were
designed to evaluate the product using several
different parameters, specific function &
performance tests for the systems, and structural
evaluations. Extreme driving manoeuvres were
also used to evaluate operator safety, load
stability, and machine performance during this
trial which was successful, and the truck during
the IM visit was running through its first field
operation trials at the mine.
What is new about the T 236 is that it has
electric drive, traditionally confined to the
ultraclass, and that it combines this with state of
the art wet braking. With its IP 68-rated plug and-
drive power modules it is also safer and more
efficient from a maintenance point of view; while
the revolutionary in-line electrical power train
layout minimises cable length. Finally, the
ergonomic T 236 cab and the superior properties
of the front wheel suspension system promote
driver efficiency with superior comfort, safety,
acceleration and handling for increased
performance. But for the real insight, here is what
senior managers Dr Joerg Lukowski, Executive
Vice-President and Dr Burkhard Richthammer,
Managing Director, Design and Engineering have
told us about the new Liebherr Mining truck...
L
Q Why the Erzberg mine as a trial location for the
T 236?
20 International Mining | JANUARY 2018
BR: Erzberg has an interesting mine site set up for
100 t trucks in combination with the use of wheel
loaders. The site organisation allows the wheel
loaders to already have the material prepared at
the loading spots, and the trucks are running
more or less all t he time without much queuing at
all, meaning it was a good test site for the T 236
as we are expecting a high machine utilisation.
The Mine blends the ore and uses lower tonnage,
single row blasts for a selective mining process.
The mine also has a number of challenging ramps
reflecting the topography, with both uphill and
downhill haulage cycles, and constant variation of
grade. It also has very variable climate. It is an
alpine mine active for more than 330 days each
year and has continuous 24 hour operation. The
climate conditions can vary from snow with
temperatures of -20°C to summer heat, with in-pit
temperatures that can reach 40°C. A particularly
interesting climate profile is that in a matter of
hours, it will intermittently switch between rain
and sunshine. This all translated to an ideal
challenge for our truck. Lastly, they run a
competitor fleet of mechanical drive trucks
making for a good comparison from that
standpoint.
Q What is unique about the T 236 in an already
very crowded 100 t truck market? How did you
arrive at the decision to go down this design
route?
BR: It’s a combination of the braking system
together with the Litronic Plus Generation 2 AC
diesel electric drive in that form and in this truck
The VA Erzberg iron ore mine offered an ideal
challenge for the new truck
class. The T 236 is the first 100 t truck which
combines an oil immersed, 4 corner wet braking
system with a diesel electric drive system. Other
electric trucks that have been made in this class
have diesel electric drives but are still using dry
brakes. That will only allow them to do the
retarding or if you like ‘maintenance free braking’
on the rear axle, which isn’t ideal in wet
conditions. In wet conditions, with 4 corner
retarding, you are still able operate our machine
much more safely than by relying on rear axle
retarding. Wet brake lifetime can be up to approx.
20,000 hours and beyond, dry brakes in the case
of a lot of use can mean workshop time
significantly more often. This is why many mining
customers wanted a 100 t truck with wet brakes
and why they asked us to develop one to get the
maintenance savings on top of the enhanced
safety. It also has an innovative, variable hydraulic
system that lowers machine parasitic losses to
provide maximum possible power for the drive
system.
JL: And don’t forget we have the other truck
models, including the T 284 and the T 264 so have
a lot of experience in applying advanced braking
systems on those. But to go back to 2012/2013 at
the start of this journey, we did an extensive
market study that showed first and foremost
mines were ready for a 100 t class diesel-electric
truck, with the better acceleration and starting,
and increased speed on uphill ramps. We started
developing two 100 t model concepts in parallel
on a feasibility basis; and realised soon that the
combination of wet brakes and electric drive
offered the greatest potential. Moving forward to
today, Erzberg have told us a big advantage of the
truck is its adaptability and flexibility in their mine
in that to some extent its systems, particularly the
drive and torque curve, can be programmed to
adapt to changing conditions and changing mine
set-up over the months and years, such as new
haul road layouts, particularly the ability to
handle steeper or shorter ramps. So the T 236 is
able to handle a wide range or working
environments in a mine with the same high
performance.
Q Can you go into more detail on the flexibility
advantage from an operational point of view?
BR: With the electric drive you are completely
decoupling the engine speed with the speed on
the rear wheels. There is no mechanical
interaction anymore, which gives us the freedom
to manage and change all the parameters as we
want. Same thing with the retarding, going
downhill we are able to adjust it required,