Paccar DAF CF - Regenerating DPF, Emission Aftertreatment System

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Driving
7.5 REGENERATING DPF, EMISSION AFTERTREATMENT
SYSTEM
Introduction
To meet the Euro 6 emission requirements, the engine has an Emission Aftertreatment
System (EAS).
The EAS provides aftertreatment of exhaust gases to reduce exhaust gas emissions.
The EAS can be divided into:
– The DPF system
– The SCR system.
– The EGR system.
The DPF system
The DPF system is used to reduce the soot particles in the exhaust gases.
DPF is an abbreviation of Diesel Particulate Filter.
Exhaust gases enter the DPF system where the particulate filter traps soot from the
engine exhaust gases.
The DPF is cleaned (regenerated) automatically. This regeneration of the DPF has
three levels:
– Passive regeneration
– Active regeneration
– Forced stationary regeneration.
The three levels of regenerating the DPF
1. Passive regeneration.
If the temperature of the exhaust system rises above a certain level during vehicle
use, the soot is burned automatically in the DPF. This is a continuous automatic
process, and no indication is shown on the master display.
2. Active regeneration.
When the temperature in the exhaust system is too low for passive regeneration to
occur, the system performs mobile active regeneration. To raise the temperature of
the exhaust gases, extra fuel is injected into the exhaust and converted into heat in
the DPF system. The EAS system initiates this process; it can occur at any time.
Active regeneration starts and stops automatically, depending on vehicle
conditions.
3. Forced stationary regeneration.
If the vehicle is operated in such a way that active regeneration does not occur or
is not completed, the DPF cannot be cleaned automatically. Examples of such
situations include only driving short distances or driving with low engine loads. In
these cases, the DPF may exceed the maximum soot level and four levels of
system warnings are displayed. They advise the driver to conduct forced stationary
regeneration. See section 'Master display notifications'.
DW63246305.book Page 208 Friday, March 22, 2019 4:54 PM