Cummins unveils Stage V nonroad engines without EGR
19 April 2016
At the Bauma show last week, Cummins unveiled a range of new nonroad (off-highway) diesel engines—spanning a power range from 74 to 625 hp—that meet Stage V emission regulations, which are expected to become effective from 2019.
The new generation of Stage V engines between 100 hp and 430 hp (75-321 kW) feature a simplified, EGR-free architecture. The new non-EGR engines deliver about 10% more power and almost 20% more torque, averaged across the range, compared to their Stage IV predecessors. The Stage V engines have been renamed F3.8 (3.8 L, 155 hp top rated power), B4.5 (200 hp), B6.7 (6 cylinders, 326 hp) and L9 (430 hp).
The non-EGR architecture follows the first Cummins engine without EGR—the 12 liter, Stage IV QSM12 launched in 2013. For Stage V applications, Cummins 12 and 15 liter units are renamed X12 (512 hp) and X15 (675 hp), respectively.
To meet the Stage V particle number (PN) limit of 1×1012 1/kWh, all of the Cummins Stage V engines are equipped with a diesel particulate filter (DPF). The Stage V PN limit signals the end of emission standard harmonization between the EU and the United States. A large proportion of US Tier 4 engines do not utilize particulate filters and the US EPA has no immediate plans to tighten the Tier 4 emission regulations.
The higher power Cummins Stage V engines use urea-SCR for NOx control, while the F3.8 utilizes an engine-mounted DPF without SCR.
Improvements to fuel efficiency result in a 3% reduction, on average, of the overall fluid cost of the Cummins Stage V engines, compared to Stage IV equipment. Start-stop technology is embedded in the engine management system, offering an additional potential fuel saving of 5-15%, depending the amount of idle time. The engine oil change interval has been extended on the Stage V engines to 1,000 hours, twice as long as the current 500 hours.
The new Stage V engines use a single Cummins turbocharger. Wastegate turbochargers are used for the F3.8, B4.5 and L9 engines. The B6.7 utilizes the Holset VGT variable geometry turbocharger.
Cummins Emission Solutions unveiled further developments of the Single Module™ aftertreatment system that offers up to a 30% reduction in weight and up to 50% in size compared to today’s Tier 4 systems. Already announced for 6-cylinder engines, variations of the Single Module system—including a new Flex Module™ package—are to be introduced on equipment spanning from 74 hp to 430 hp (55-321 kW). The system has been designed to help customers to fit the product into the challenging space claims often seen in off-highway applications.
In addition to the Flex Module, Cummins is also developing a Single Module aftertreatment system for 4 cylinder engines, intended for Stage V engines in the 74-200 hp (55-150 kW) power range. The concept product would offer customers an option to engine-mount the aftertreatment while delivering improved NOx conversion in the SCR system and a greater ash capacity in the DPF with the use of “advanced” catalyst technologies, said Cummins.
The new nonroad engine platform will be available globally, offering OEMs the possibility of using the same Cummins engine in their equipment worldwide. The engines will be offered with or without exhaust aftertreatment, depending on the respective emission requirements and diesel fuel quality.
Source: Cummins