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Construction Equipment & Transport
A
ccording to Rod Watson,
Managing Director of DISA
Equipment, trading as Doo-
san, “This investment in the latest
technology gives users the guarantee
that Doosan machines offer efficient
output power, low fuel consumption,
minimal maintenance requirements
and extended service life. Operator
safety, precise control and comfort
are key to product advancement.
With the addition of Doosan’s
DLA wheel loader series to the range
nearly two years ago, Doosan has
made inroads in the South African
wheel loader market.
“Doosan earthmoving equipment
encompasses heavy, wheel and mini
excavators, articulated dump trucks
(ADTs), as well as wheel loaders,
and have been designed to cope ef-
ficiently and safely in Africa’s harsh
operating conditions.”
The DLA series includes four wheel
loaders – DL200A, DL250A, DL300A
and DL420A – with bucket capaci-
ties of between 2,0 m³ and 4,5 m³,
with optimised breakout force and
machine balance. The operating
weight of these wheel loaders has
been increased, with greater tipping
load capacities. These environmen-
tally friendly machines are driven by
Doosan Tier 2 engines, which are less
sensitive to fuel quality than Tier 3 en-
gines, yet still offer reduced fuel con-
sumption and lowexhaust emissions.
The Doosan air to air intercooler
engines offer high torque and low rpm
for improved response. High power
and torque characteristics, coupled
with efficient synchronisation of the
drive train with the hydraulic system,
ensure optimumproductivity, even in
tough operating conditions.
The DL300A and DL420A units are
widely used in local conditions and
have the flexibility to handle diverse
materials such as granular as well as
bulk loads.
The DL300A wheel loader, with an
8 litre DoosanDE08TIS engine (156 kW
at 2100 rpm) engine and the DL420A
wheel loader, with an 11 litre Doosan
DE12TIS engine (210 kWat 2100 rpm),
have been designed for advanced dig-
ging power and high traction for the
penetration and handling of even the
hardest materials. The high strength
drawbar pull at the wheels is rein-
forced by limited slip ZF differentials
as standard equipment. This feature
also reduces the risk of skidding and
prevents excessive tyre wear.
Metal reinforced brake discs are
integrated into the planetary reduc-
tion gears in the hubs where the rota-
tion speed is lower. As a result, discs
are exposed to lower rpm and heat
generation is reduced. This ensures
improvedmachine stability, extended
hours of operation and reduced
maintenance requirements. For user
convenience, brake disc wear can be
measured without disassembling
the hub.
Thesemachines have higher static
tipping loads at maximum reachwith
a straight frame DL300A (13 650 kg)
and DL420A (17 900 kg). Other qual-
ity improvements of the DLA series
include a newhose, which is installed
in the air breather of ZF axles to pre-
vent breather congestion problems.
In other wheel loaders, dust and sand
cause clogging of the air breather,
resulting in elevated oil temperatures
and damage to the seals on the axles.
Buckets have been reinforced for
additional strength. Aluminium radi-
ators are installed on rubber mounts
to dampen vibration and the radiator
grille is made of reinforced steel for
increased shock resistance. A cover
has been fitted to the propeller shaft
to protect the oil seal from dust and
foreign objects. This reduces wear
and extends service life. The high
lift arm ensures an improved dump
reach and height at bucket pivot
point. The Load Isolation System
(LIS), which is standard, suspends the
bucket using a closed accumulator to
reduce material loss.
The design of the DLA series has
also been improved for enhanced op-
erator comfort. There ismore space in
the cab, improved visibility, push but-
ton controlled air conditioning and
heating, a comfortable air suspension
seat and convenient storage space.
■
High performance low emissions
Doosan’s heavy earthmoving equipment and ongoing
development programme to manufacture robust
machines with high performance materials to reduce
running costs and low emissions has paid off.
July 2015