Cummins introduce the X12 engine at Busworld for touring and intercity coaches

Brussels, Belgium
X12 Cummins Coach Engine

Innovative architecture ready to redefine power efficiency for Euro VI Phase-D

BRUSSELS, Belgium (Oct.17, 2019) — Today at the Busworld Europe show Cummins introduced the X12 engine with up to 480 hp (360 kW) output for powering full size touring and intercity coaches. Certified to the stringent Phase-D stage of Euro VI regulations, the X12 incorporates innovative architecture and a highly efficient in-cylinder combustion formula eliminating the need for exhaust gas recirculation (EGR).

Other advanced design features include techniques to minimize friction losses and a  weight-saving sculptured engine block. The result is a fuel-saving 11.8-litre engine with a remarkably low weight under 920 kg, but with the heavy-duty strength and uncompromising on-road performance required for 12-to-15 metre high deck coaches.

The high flow air-handling system of the X12 gives a faster pedal response to enhance driveability at full vehicle loading, together with a rapid gradient climbing ability. A high peak torque of up to 2300 Nm is delivered across a wide engine speed range, so less shifting is needed, and less fuel is used. Equally powerful is the engine braking with 370 hp (275 kW) delivered at 2100 rpm.

The sculptured block design allows unnecessary mass to be removed but retains high rigidity. Substantial weight savings are also achieved by using high-strength composite materials for the oil pan and valve cover. A key design approach with the X12 was to minimizing friction losses throughout the engine, including the water pump, gear train, lube system and power cylinder.

The XPI fuel system on the X12 is derived from the more powerful X15 engine, with Cummins injection technology enabling smooth and rapid engine response to increasing vehicle demands, while minimizing fuel consumption. XPI also contributes to reducing engine noise, vibration and harshness (NVH) to provide a more relaxed journey.

The X12 will set a new benchmark in its class by providing unprecedented levels of performance for coaches in Europe and markets around the world as they transition to meet Euro VI equivalent emission standards,” said Brian Wilson, Cummins Executive Director – Global Bus Business.

“With the engine now in full production we are delighted to see the first coaches with the X12 and the lower displacement X11 version appearing at Busworld Europe on the  King Long display, powering their latest C13HD High Deck and U13 Intercity coach,” added Wilson.

The X12 is a next-generation evolution of Cummins 12-litre Euro V engine, proven in truck and coach applications worldwide as the ISG12. The Euro VI engine takes advantage of Cummins latest U-module compact box aftertreatment with integrated AdBlue dosing, providing a more simplified vehicle integration. Active regeneration of the aftertreatment is reduced to a minimal level and service cleaning intervals are extended.

EGR-Free Combustion

The EGR-free X12 lowers heat rejection by around 40 percent compared with that of similar engines using cooled EGR, allowing the full power potential of the X12 to be realized while meeting Euro VI Phase-D.

No EGR means a lower combustion temperature and less to cool, which helps to reduce the vehicle integration effort and cost. X12 architectural simplicity is further reflected in the use of a Cummins high-efficiency wastegate turbocharger, as the base engine already provides high power density without requiring a more complex turbocharging boost system. 

The simpler, but stronger architecture of the X12 contributes to the goal of a global engine platform. While meeting Euro VI, the X12 and the X11 version are co-certified to meet NSVI in China and are ready to meet equivalent low emission standards as they are introduced in countries including Brasil, India, Australia and Mexico.   

Nearer-To-Zero Phase-D

The low emissions credentials of the X12 are further enhanced by meeting the Phase-D requirement of Euro VI, representing a nearer-to-zero incremental step that will help coach fleets align with the introduced of Low Emission Zones being established in European cities.

The Phase-D regulations focus on tighter control limits for Nitrogen Oxides (NOx) emissions during lower speed operations, as well as under cold engine start conditions. In addition to emissions test cell verification, the Phase-D regulations required on-road testing to capture real-world measurement.

Duty cycle-based testing using high precision Portable Emissions Measurement systems (PEMs) installed on Cummins-powered vehicles has indicated a 25 percent reduction in NOx emissions, compared to the Phase-A engines when Euro VI was introduced in 2015.

This Phase-D development work required a substantial investment by Cummins to meet the stringent requirements without the need to change engine hardware. The design focus stayed on the control logic and creating a new algorithm for the emissions management system, by refining and retesting the software over a two-year period

About Cummins Inc.

Cummins Inc., a global power technology leader, is a corporation of complementary business segments that design, manufacture, distribute and service a broad portfolio of power solutions. The company’s products range from internal combustion, electric and hybrid integrated power solutions and components including filtration, aftertreatment, turbochargers, fuel systems, controls systems, air handling systems, automated transmissions, electric power generation systems, microgrid controls, batteries, electrolyzers and fuel cell products. Headquartered in Columbus, Indiana (U.S.), since its founding in 1919, Cummins employs approximately 59,900 people committed to powering a more prosperous world through three global corporate responsibility priorities critical to healthy communities: education, environment and equality of opportunity. Cummins serves its customers online, through a network of company-owned and independent distributor locations, and through thousands of dealer locations worldwide and earned about $2.1 billion on sales of $24 billion in 2021.

Media Contact
Kevan Browne
Director - Marketing Communications, On Highway Bus
44 (0)7718 581313
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