2018
SURFACE MINING
Aleksandr Egorov
leksandr Egorov has devoted more than
40 years of his life to work at OJSC
“BELAZ” with more than a half of this
period being involved in research, development
and implementation of many ambitious
engineering projects, including but not limited
to development of the 240-t and 360-t trucks
and development of the autonomous truck,
development of the first in the world 90-t truck
with electric drive. All of these projects he was
in charge of demanded the development of
great many unique technical solutions, but none
of them was probably as demanding as the
project for the development of the mining dump
truck BELAZ-75710 with payload capacity of 450 t.
One factor driving the project was the global
financial crisis when mineral extraction was
decreasing together with commodity prices. In
these conditions, mining companies were
seeking new equipment with higher payload
capacity, capable of moving bigger volumes in
one cycle, and providing lower operational cost
due to fuel efficiency.
It is also worth mentioning that the first
attempt of creating a ultra-high payload
capacity dump truck (more than 400 t) was
made by the engineering team under command
of Egorov back in 1997-1998. The concept was
developed in response to a request made by
Chilean copper mining company CODELCO. But
although the concept was approved by the
customer, the practical realisation of this project
was not feasible due to the unique design of
many components together with various
limitations of manufacturing capabilities.
Nowadays, having at their disposal more
advanced technological levels of production
capabilities and rich experience based on
previously implemented projects, the
engineering team under Egorov’s command was
able to develop this unprecedented product.
Nevertheless, during the development process
A
First assembled BELAZ-75710 truck at the factory
HoF 6 International Mining | JUNE 2019 Supplement
the engineering team had to face a wide variety
of challenges and to invent unique solutions to
resolve them. It would be worth mentioning at
least a few.
The first one is quite obvious. How can you
achieve the 25% increase of payload capacity
when there are no bigger tyres available on the
market? How you do provide the possibility of
truck operation in the same conditions together
with other super-size trucks without the need
for the end-user to change the mine profile,
road width or loading equipment? How can you
provide enough power to move such a load
without a drastic increase in fuel consumption?
Original steering kinematics design
To solve these issues, it was decided to use
eight tyres with the highest possible payload
capacity of 105 t. But this in turn created new
challenges connected with the arrangement of
the wheels and steering schematic of the truck.
To address these challenges, the engineering
team developed a unique suspension system
that features two steerable axles on two semi-
frames. This solution allowed not only to keep
the rigid frame but also to remove a certain
number of loads from it and achieve a turning
radius of less than 20 m with all-wheel drive
and four-corner electrodynamic braking on top
of that with the application of two driving axles.
In order to provide sufficient power, it was
decided to use two engines with two electric
drive systems (one per axle), which in turn
required
development of the
solution to match
two drive systems to
provide optimal
control and smooth
driving.
It was a hard hit-
or-miss way and
Egorov was entirely
responsible and
involved not only in
developing ideas and
concepts and finding
a right solution from scratch
for constantly arising
challenges and issues, but
also in bringing together
and accommodating the
opposed conceptions from
different working groups in
the engineering team and
keeping the project moving in the right
direction.
In 2013, the first pilot truck was
manufactured in metal and even the first trials
at the factory testing grounds proved the
correctness of the applied technical solutions
for the design of the dump truck. Field testing in
the tough operational conditions in the Kuzbass
region (Russia) revealed further benefits of the
truck design, including 15% fuel economy due
to optimal settings of the engine-alternator
units (when driving without load, the truck
automatically switches to using only one
engine) compared to 360-t BELAZ trucks
working in the same mine. Dynamic unloading
due to the powerful hydraulic drive
compensated for the additional time for loading
of the larger volume body. Initial concerns in
regards to tyre wear due to use of four dual
tyres proved to be wrong. Application of the
innovative steering kinematics provided
excellent manoeuvrability and showed a 10%
decrease of tyre wear compared to the
traditional 2x4 wheel arrangement of the mining
trucks operated in the same conditions.
BELAZ-75710 in operation
Due to all of these reasons, the operating
company placed an order for two more BELAZ-
75710 trucks prior to the end of the testing
period.
Since the production of the first truck, the
engineering team under the command of Egorov
has been awarded more than six inventors
certificates for different units and systems of
the dump truck. The unique suspension design
was honoured by the Swedish Steel Prize (an
engineering contest held by Swedish steel
manufacturer SSAB). The truck acheived two
entries in the Guinness World Records book.
By the end of the testing period (end of July,
2017), the truck moved more than 6 Mt with
total mileage of more the 70,000 km.