In the runup to Bauma, the mantra for Cummins is "4 More for Tier 4," indicating the company's intent of revealing its next generation of four-cylinder QSB3.3 and QSB4.5 engines for compact equipment, together with a first showing of the all-new QSX11.9 and QSX15 heavy-duty engines. The Tier 4 Interim engines will be on display as complete air-intake-to-exhaust aftertreatment systems, with all key technologies integrated by Cummins.
The four new engines will join the previously shown QSB6.7 and QSL9 MidRange family in the Cummins booth at Bauma to complete a wide 75- to 600-hp (56- to 447-kW) power lineup for Tier 4I. The standard takes effect in North America and the EU in January 2011 for engines above 173 hp (129 kW) and in January 2012 for engines above 74 hp (55 kW).
The compact 3.3- and 4.5-L QSB engines extend from 75- to 160-hp (56- to 119-kW), enabling standardized four-cylinder installations with common Tier 4I architecture.
Covering a power band from 300 to 600 hp (224 to 447 kW), the all-new 11.9- and 15-L QSX engines share the same performance-enhancing technology for Tier 4I, such as Cummins' new XPI common-rail fuel system.
According to Hugh Foden, Executive Director, Cummins Off-Highway Business, all four engines "bring a new power capability to the equipment industry for Tier 4 that goes beyond achieving very low emissions. They will realize up to 5% higher fuel efficiency and improve productivity. Additionally, our single-system approach, from air-intake-to-exhaust aftertreatment, enables easier machine integration for OEMs."
The QSB3.3 and QSB4.5 engines feature a scaled-down cooled exhaust gas recirculation (EGR) system and Cummins particulate exhaust aftertreatment, sized for compact equipment. Cummins new Direct Flow air cleaner takes up to 35% less space compared with typical Tier 3 filters with equivalent or longer service intervals.
A key design focus for the four-cylinder engines has been to avoid over-engineering with complications such as dual turbocharging. Instead, Cummins says the QSB3.3 and QSB4.5 use a simpler variable-flow turbocharger across the complete power range.
Cummins new XPI fuel system, incorporated into both Tier 4I QSXs, provides what it says is "the most capable common-rail technology ever seen on a heavy-duty platform," able to inject a precise quantity of fuel at extra-high pressure up to 35,000 psi (2400 bar). Both power and torque delivery are significantly faster to boost machine productivity beyond that of Tier 3 engines, says company engineers.
The XPI system is complemented by a single Cummins VGT turbocharger that is able to continuously vary airflow boost to match engine rpm and load demands. Cummins new Direct Flow air cleaner includes an integrated sensor for monitoring temperature and pressure to ensure optimum airflow.
Both QSXs use Cummins' proven cooled EGR to reduce NOx emissions by 45% and a Cummins Particulate Filter to remove over 90% of PM emissions.
At the other end of the scale in terms of Cummins' engine offerings is the 78-L QSK78 mining engine, which will be on display at the booth, representing Cummins' high-powered engines to manufacturers of large mining haul trucks and excavators.
The V-18 configuration QSK78 was the first engine to bring a 3500-hp (2610-kW) power capability to ultraclass mining haul trucks operating at high altitudes. The QSK78 was also the first engine of its size to feature a full-authority electronic management system, enabling engine parameters to be customized to precisely match the duty cycle of the equipment.
Cummins mining display will also feature cost-saving technologies for the mine operator, such as the Eliminator self-filtration system, which replaces disposable oil filters on the engine and enables oil change intervals to be extended up to 100 h.
Ranging from 19- to 78-L, Cummins says that while competitive engines in that range are designed primarily for less demanding applications such as power generation, rail, or marine, the QSK engines are first and foremost conceived to meet the toughest demands of the mining industry.
QSK engines are said to handle high hour and high engine-load factors on a fuel-efficient basis and achieve uptime levels over 95%.