Iveco chose the SCR technology to make the range of medium and heavy vehicles complies with Euro 4 and Euro 5 . The
reduction of nitrogen oxides in the exhaust system by means of an
additive - AdBlue - is the solution adopted by Iveco for medium and
heavy range , as it allows both to respect the environment and to ensure
the profitability of transport through a reduction in operating costs , two fundamental factors for Iveco . The
choice of this method of post- processing also allows to anticipate the
availability of vehicles complying with Euro 5 emissions of the
Directive . Thanks
to the adoption of SCR technology , Iveco is able , since the second
half of 2005 , to provide vehicles that allow carriers to qualify for
the incentives in many European countries for the early use of vehicles
with emission Euro 4 & 5 .
The dilemma posed by the Directives Euro 4 and Euro 5
The Directive has placed at Iveco Euro 4 , as well as other manufacturers , a difficult problem :
against the Euro 3 , reduce the rate of particulate emissions by 80% and the rate of nitrogen oxides
of 30%. The Directive Euro 5 requires , in turn , a further 40% reduction of nitrogen oxides .
Now , the present state of knowledge and technologies in the field of injection , interventions on
combustion are able to reduce the rate of one pollutant only increasing emissions
other. From here the necessity to resort to the post- treatment of exhaust gases to complete the action
turning inside the motor. The situation is identical to comply with the Euro 5 emission limits .
At this point , the builders have two options . It is possible to reduce the rate of nitrogen oxides in the
combustion chamber , decreasing the temperature through an intake of exhaust gas in the air
aspirated at the time of combustion . These gases , which replace a portion of the intake air
from the engine , should be accurately dosed and cooled within a heat exchanger fed
from the cooling system of the engine. In parallel , the injection advance is reduced .
Any decrease in combustion temperature results in a lower return on
engine. The other drawback is represented by the marked increase in the concentration of particulate
in the engine and , in particular, in the recirculated exhaust gases . This phenomenon can cause pollution
lubricating oil , which must therefore possess a greater capacity to the particulate dispersion .
The particulate is treated downstream of the engine , in the exhaust muffler , with the aid of a filter.
These features , which are negligible for small engines , are very relevant when
you go with the power . The recirculation of exhaust gases is known with the name of EGR (Exhaust Gas
Recirculation) . Lately, this solution has been adopted by some manufacturers also
for medium and heavy trucks to meet the Euro 4 limits . For Euro 5 , always in the current state of
technologies , EGR + particulate filter is not sufficiently effective for engines
large displacement , even if does not require the addition of an additive to enter the drain.
With the solution EGR , there is an increase of weight of the vehicle compared to Euro 3 .
The SCR - Selective Catalytic Reduction - is the other way chosen by Iveco and the most
Most manufacturers of medium and heavy vehicles . It consists of optimizing the combustion of
motor to minimize the particulate content in the exhaust gas . the yield
engine resulting improved, with a consequent reduction in fuel consumption . the oxides
nitrogen , where the rate in the exhaust gas is higher than the limit , are treated in a catalytic filter
place in the silencer , after placing of a liquid reductant upstream of the filter itself . the oxides
are thus transformed into nitrogen and water vapor totally harmless . The reducing agent is ammonia ,
which is stored in the form of an aqueous solution containing urea , marketed with
in the name of AdBlue . The SCR technology eliminates the particulate filter , as this type
emission is directly knocked down during the combustion phase , the catalyst burns
remaining particulate simultaneously to the treatment of nitrogen oxides .
Even in this case there is an increase of weight of the vehicle compared to a equivalent version
€ 3 .
The reasons for the choice of Iveco to adopt the SCR system
The SCR system chosen by Iveco achieves an ideal compromise between the two objectives
essential that the engine designers have set themselves to meet the needs of customers : on the one hand ,
improve the efficiency of the engines to reduce fuel consumption and operating costs , prolonging the
while the duration of the power units , on the other hand, comply with the emission limits established
by the European authorities to protect the environment . Naturally, the more the fuel consumption
per tonne of transported goods is reduced, the motor emits much less CO2 gas , which is responsible
the phenomenon of global warming.
Iveco has initiated research into the reduction SCR in 1994 at its center of Research and Development
Arbon , Switzerland (Iveco Motoren Vorschung ) and part of a consortium created along with other
manufacturers. Iveco has also explored the EGR solution , in adopting it on their light vehicles
where , for this type of use, is the ideal compromise between different factors (consumption, weight, cost ) .
For medium and heavy vehicles , due to the high average annual mileage recorded , the advantage
represented by the reduction of fuel consumption becomes predominant . Moreover, the procedure
SCR does not detract in any way nor the quality of the lubricating oil or the oil change intervals .
Indeed , the low particulate content in the combustion chamber allows to extend
further these intervals. Similarly, the system is not sensitive to the sulfur content of the diesel fuel.
Unlike EGR technology , the SCR process does not require a greater use
the cooling system of the engine. Now , everyone knows that , in the presence of high power , the
dimensions of the radiators pose serious problems of lay-out of a heavy vehicle and that the increase of
fan performance and penalizes absorbs power consumption.
The ability to anticipate the Euro 5 directive
A fundamental advantage of the SCR system lies in the fact allow the achievement of values
emissions of both Euro 4 and Euro 5 , which allowed Iveco to simultaneously develop a
solution for both emission levels. Thanks to the modern architecture of its engines and,
Specifically, the electronically controlled unit injectors , controlled by a camshaft place
directly in the cylinder block , Iveco has been able to develop a new injection with pressures
high and a finer atomisation of the fuel. With Iveco Cursor engines , the consumption of AdBlue
is 4-5 % for Euro 4 , equal to about 1.5 l/100 km, and slightly higher for Euro 5 . With a consumption
of 60 l of urea, for example, the range is over 3,500 km.
The injection system of AdBlue has been developed in extreme weather conditions to keep
account of the physical characteristics of this additive , and especially of its progressive crystallization
below -11 ° . Test campaigns were organized in Scandinavia and Spain , in addition, numerous
test vehicles undertake extended to customers.
Iveco , therefore , is ready to offer simultaneously heavy vehicles Stralis both in the version
EUR 4 is in the Euro 5 . Iveco expects that the demand for such vehicles will concentrate on countries that
provide financial incentives for the early adoption of the deadlines set by the European Directives.
This is the case of Germany, Switzerland and Austria.
Models Iveco Euro 4 & 5 in advance on the terms required
Models Euro 4 & 5 available in advance of the deadlines for mandatory adoption , comply
the current legislation ( EEC 88/77-EC 1999/96-EC 2001/27 ) and meet priority
the demand of the markets that offer financial incentives. These are the following models : 4x2
and 6x2 trucks , both available in two versions with engine : 430 HP Cursor 10 or Cursor 13
480-hp , all with Stralis Active Space cab . The first deliveries are scheduled for September
2005. For other countries in which carriers wishing to anticipate the Euro 5 Directive due to a
heavy traffic with Germany or Austria (in general with countries where incentives apply ) , deliveries
will begin in November of this year.
Table of models :
step
Cursor 10 engine 430 hp
Cursor 13 engine 480 hp
Tractor 3500 - 3800 mm
AS 440 S 43 T / P
AS 440 S 48 T / P
Wagon 4500 - 4800 mm
AS 440 S 43 Y / PS
AS 440 S 48 Y / PS
The Euro 4 and Euro 5 vehicles will undergo price changes differ from country to country.
