HYDRAULIKPRESSE - HANSA-FLEX Hydraulics Canada Inc.

TEREX GMBH
In the search for crude oil rising oil prices and a foreseeable
scarcity of resources have now prompted the
exploitation of sources which were not previously lucrative
enough. One example of this is the enormous
oil sand fi elds at Fort McMurray in Canada.
The province of Alberta contains around one third
of the world’s available stocks of oil sand, which is
mined at open pits by mighty crawler excavators. It
is here that North America’s largest crude oil producer
Syncrude Canada Ltd. (SCL) operates three
opencast mines. Gigantic RH 400 mining excavators
from Terex O&K are used to extract the oil sand.
Terex GmbH based at Dortmund, a successor company
to O&K AG founded in 1876, has repeatedly set
milestones in the development of hydraulic excavators
and specialises in extraction and conveying
at opencast mines. At Fort McMurray not only hydraulic
but also cable-operated and bucket-wheel
6
Mining excavators - giants in oil sand
„Works in works“ - a tried and tested concept
HYDRAULIKPRESSE
excavators are in use. Among them is the RH 400.
With an operating weight of some 1,000 tons it is
the world’s largest hydraulic excavator, with jumbosized
dimensions. The excavator bucket alone has a
capacity of 45 cubic metres, able to handle around
100 tons of oil sand in a single pass. This calls for
enormous forces - something that the RH 400 can
deliver thanks to an engine output of 4400 HP and
hydraulics that can cope with operating pressures
of up to 310 bar. Oil sand can be mined in winter
at - 40 °C when the ground is frozen rock-hard, but
also in summer at + 40 °C when the oil sand has
become a stringy mass.
The extracted oil sand is then loaded onto gigantic
heavy-duty trucks with payloads of up to 360 tons,
which take it away for processing, fi nally resulting
in the coveted crude oil. Four buckets from a RH
400 will fi ll a heavy-duty truck. The mining excava-
tor is controlled from the third fl oor so to speak. It
is at this level that the driver’s cab is to be found,
equipped with a control panel as well as a kitchenette
complete with microwave and area for relaxing.
The precise control system is designed to ensure
easy operation although the skill of the driver
also plays a key role here. Surprisingly, women are
now increasingly to be found in this job: Experience
has shown that they handle their machines with
greater fi nesse.
Ordered at short notice, delivered
promptly
A new RH 400 from Terex O&K is already scheduled
to go into service at one of the three oil sand deposits
in Alberta in January 2008. The time scale
from ordering the mining excavator from the German
manufacturer to commissioning is rather
tight. Nowadays the construction of such mighty
“workhorses” must be performed in record time.
Once a mining company has decided to exploit
a new oil fi eld, it cannot wait months for delivery
of the machine required. For Terex O&K as the
partner to the mine operator this makes high demands
on its readiness to deliver. There must be
no delay in assembly under any circumstances.
Terex O&K therefore expects each subsupplier to
off er special services, something that naturally
also applies to the manufacturers of the hydraulic
connecting elements. The completed excavator is
based on designs, drawings and parts lists from an
existing model but this was last built by Terex O&K
three years ago - mining excavators of these dimensions
are not mass-produced on an assembly line.
As technical progress has not stood still since then,
technological advances must of course also be taken
into account and incorporated during construction
of the machine. This may involve new units with
modifi ed connections or new routings for pipes and
hose lines, which have come about from the experiences
evaluated by the operator over the last few
years. In such cases fi ttings need to be changed,
as well as nominal widths, with pipe manifolds
ISSUE DECEMBER 2007