Capable of producing up to 512 horsepower, Cummins QSM12 six-cylinder, 12-liter engine is designed, says the manufacturer, with a compact envelope that results in a power-to-weight ratio some 30 percent more favorable than the class average for engines with similar power ranges.
Capable of producing up to 512 horsepower, Cummins QSM12 six-cylinder, 12-liter engine is designed, says the manufacturer, with a compact envelope that results in a power-to-weight ratio some 30 percent more favorable than the class average for engines with similar power ranges. It meets EPA Tier 4-Final standards without a cooled-exhaust-gas-recirculation (CEGR) system, reducing internal loads on the engine and lowering cooling requirements by 40 percent, the company says, compared with similar engines using CEGR systems. A key design focus for the QSM12 was significant weight reduction in order to increase the power-to-weight ratio. To that end a sculpted block retains high rigidity but removes unnecessary mass, and the use of composite materials for the oil pan and valve covers results in further weight savings. Weight of the new engine is 1,900 pounds, yielding a power-to-weight ratio of 0.27 horsepower per pound. According to Cummins, the QSM12’s attributes provide the opportunity for equipment makers to downsize engines, but to retain performance. Featuring the electronically controlled Cummins Xtra-High Pressure Injection system, the QSM12 produces a peak torque of 1,700 lb.-ft. and available torque rise as high as 60 percent. The emissions-control system, designed by Cummins Emission Solutions, incorporates a diesel particulate filter and selective-catalytic-reduction (SCR) system. The SCR system, says Cummins, is a next-generation design using a copper zeolite-based catalyst capable of converting more than 95 percent of nitrogen oxides. According to Cummins, operators of QSM12-powered equipment “can expect—and may exceed—12,000 hours before overhaul, with no mid-life engine-overhaul required.” The new engine also features Cummins’ Direct Flow air-filtration system and two-stage fuel filtration using NanoNet media from Cummins Filtration. The fuel-filtration system, says Cummins, traps “almost 99 percent of all particle as small as 5 microns.”