InfraStructures - April 2008 - Cummins Announces QSX for Tier 4

Cummins Announces QSX for Tier 4

Cummins Inc. announced at CONEXPO-CON/AGG that the Heavy-Duty QSX engine will be available with a fully integrated air intake to exhaust aftertreatment system to meet U.S. EPA Tier 4 Interim and European Stage IIIB off-highway emissions regulations in January 2011. The Tier 4 QSX increases displacement to 16 l and incorporates the XPI High Pressure Common Rail fuel system to enhance power output and engine response.

Very low emissions levels are achieved with Cummins Particulate Filter exhaust aftertreatment that reduces particulate matter emissions by 90% and cooled exhaust gas recirculation that reduces oxides of nitrogen (NOx) by 45%. The Tier 4 QSX also features a crankcase filter to eliminate blowby gas emissions.

Performance-enhancing Tier 4 technology brings a significant increase in QSX power output with an unrestricted top rating of 650 hp compared to 600 hp for the current Tier 3 QSX. Ratings will extend down to 400 hp to cover a broad range of heavy-duty applications. Peak torque is increased by 12% to 2150 lb-ft with faster torque delivery available across the engine rpm range.

Cummins XPI fuel system enables multiple injection events with very high fuel injection pressure across all engine rpm speeds to enable both cleaner combustion and improved engine response. The XPI fuel system is complemented by a Cummins Variable Geometry Turbocharger with a sliding-nozzle design. The nozzle continuously varies the airflow boost to precisely match engine rpm and load demands.

The Cummins particulate filter replaces the muffler in the exhaust stream and offers equivalent noise reduction qualities. The filter is especially strengthened against shock loads and vibration to meet the most severe off-highway operating conditions.

The Particulate Matter collects on the filter and is gradually oxidized by catalytic passive regeneration. With some duty cycles, PM accumulation rate may eventually exceed oxidation rate, and a short active regeneration is initiated by the engine electronic control module utilizing the XPI fuel system and Variable Geometry Turbocharger.

Cummins ability to design, build and integrate the complete Tier 4 QSX engine system from air intake to exhaust aftertreatment offers substantial packaging efficiencies for equipment manufacturers. The engine ECM will integrate with equipment electronics, including CANbus common area networks for J1939 and ISO multiplexing.

The QSX is available with the new Cummins Direct Flow air filtration system by Fleetguard, specifically developed for Tier 4 applications. Direct Flow offers a 35% smaller installation profile than typical Tier 3 air filtration systems while maintaining the same filtration efficiency. This is accomplished by creating a direct-flow path through the filter media which is packaged in a rectangular configuration rather than a conventional cylindrical shape. The Direct Flow housing includes a sensor to monitor temperature and pressure which sends data to the engine electronic control module to ensure optimum airflow operation.

Source: Cummins Inc.