MORE ABOUT UREA DOSER / UREA DOSING UNIT :
Urea Doser System / Urea Dosing Unit is an important part of any selective catalytic reduction (SCR) system, accurately designed to reduce oxides of nitrogen (NOx) emissions while providing cheap cost of ownership, performance and reliability to any diesel engine manufacturer and the owners.
The doser System like in Tata , or injector, is a robust component
that delivers an atomized urea and air mixture
upstream of the SCR catalyst. The design allows
injection in the center of the exhaust gas flow,
which minimizes the risk of deposits and improves
reliability. A relatively large orifice sizing in the
nozzle also provides exceptional tolerance to
contaminants.
SUPPLY UNIT
The urea supply unit is a high-accuracy unit for
injecting urea into the exhaust aftertreatment system.
A control module calculates the exact dosing rate of
urea based on various engine conditions, and the urea
mixes with air from the vehicle compressed air system.
Atomized urea is then sent through the injector into the
exhaust system upstream of the SCR catalyst.
Aftertreatment Control Module.
The Aftertreatment Control Module translates
datalink-commanded dosing rates into supply
module inputs to accurately deliver the required
dosing quantities. The independent aftertreatment
control module can also be used to control
other engineered components in the engine or
aftertreatment system.
How It Works?
The Urea Doser System is a reductant delivery
system that accurately injects a 32.5 percent solution
of urea in water – also known as Diesel Exhaust
Fluid (DEF) or AdBlue® – into the exhaust stream.
When exposed to heat from the exhaust, the urea
decomposes into ammonia. The ammonia reacts
with the SCR catalyst, converting NOx in the exhaust
stream into harmless nitrogen and water. To ensure
performance and maximize the environmental benefits
of the system, Cummins employs advanced control
technology.
