Four-Cylinder Diesels Meet Tier 4 Interim Standards
The latest versions of its QSB3.3 and
QSB4.5 engines in the 75–160 hp power
range will meet 2012 EU Stage IIIB and
U.S. EPA Tier 4 Interim off-highway emissions
standards, according to Cummins. The
new four-cylinder engines still retain 3.3
and 4.5 liter proven platforms and will be
sold as a fully integrated air-intake-toexhaust
system. The engines’ low emissions
output is due to cooled Exhaust Gas
Recirculation (EGR) for NOx control and
exhaust after-treatment to remove particulate
matter. According to Cummins, its High
Pressure Common Rail fuel system can be
employed to meet the Tier 4 Interim while
the compact cooled EGR system and the
after-treatment unit have been designed for
these four-cylinder platforms specifically. In
order to manage the EGR flow across the
engine power range an upgraded turbocharger
with electronic control will be
used. The particulate after-treatment unit
for the Tier 4 Interim QSB3.3 and QSB4.5
replaces the muffler in the exhaust stream;
it removes more than 90% of particulate
matter but still offers equal noise reduction.
The after-treatment unit is small, can be
installed horizontally or vertically, and meets
the toughest vibration and shock loading
requirements. The Direct Flow air filtration
system provides a 35% smaller installation
profile than radial air filters, yet supplies the
same filtration efficiency, says Cummins.
www.cummins.com
As featured in Womp 09 Vol 05 - www.womp-int.com