10 July 2001

Volvo Trucks North America, Inc. said that heavy-duty Volvo engines sold in the US market will use the cooled EGR technology to comply with the US2004 emission standards. Volvo is among the group of engine manufacturers who, by signing consent decrees with the DOJ/EPA, committed themselves to supply 2004-compliant engines by October 2002, a deadline recently confirmed by the US government.

Volvo said its engines will use a cooled EGR system called V-Pulse. All Volvo trucks equipped with Volvo Power diesels that are ordered by the fourth quarter of 2002 will utilize the V-Pulse system, which the company said allows it to retain its existing engine platform without the need for aftertreatment.

The V-Pulse system utilizes pressure pulses created by the exhaust valves and then re-circulates up to 30% of the exhaust gas through the V-Pulse cooler and back into the engine cylinder. This, combined with high pressure, modulating unit injectors, achieves the combustion required to meet the emission requirements, Volvo said.

Cooled EGR will be also used as the primary emission technology to meet the October 2002 deadline by Cummins, Mack, and DDC, but apparently not by Caterpillar.

The US2004 emission standards establish a 2.5 g/bhp-hr limit of combined NOx+NMHC, down from the current 4 g/bhp-hr NOx and 1.3 g/bhp-hr HC limits.

Source: Diesel Progress