By Alan M. Petrillo
Diesel engine manufacturers have developed engines that give fire apparatus more power from the same size units yet run stronger and cleaner.
Listening to the wants and needs of pumper, tanker, rescue, and aerial apparatus users, engine makers have been beefing up their products to meet the increased power needs of apparatus that can be found in every phase of firefighting operations.
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The ISX15 is the largest diesel engine Cummins builds for the fire
service, with ratings from 455 to 600 hp. It features strong throttle
response and pulling power as well as improved fuel economy.
(Photo courtesy of Cummins.)
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Customer- and Regulation-Driven
Chris Crowel, manager of specialty vehicle markets sales and support for Cummins Inc., says that customers and federal rules and regulations are key driving forces in diesel engine development. "The regulations challenge us to come up with new solutions, but our customers do as well," Crowel says, "and sometimes they compete with each other, which leads us to discover new technologies."
Crowel points to the technological progression in the development of diesel engines, noting, "We first started adding turbocharging and aftercooling to get more air into the system, then the use of more electronic controls, cooled exhaust gas recirculation (EGR), the addition of [the] diesel particulate filter (DPF), an oxidation catalyst, and the most recent step-selective catalytic reduction (SCR) to reduce oxides of nitrogen (NOx)."
He adds, "Hydrocarbons and NOx have been reduced to levels that almost can hardly be measured, so now the next concern will be reducing carbon dioxide (CO2) when greenhouse gas regulations go into effect in 2014. However, when Cummins released its 2013 engines, we improved them to the levels required by the coming greenhouse gas regulations."
The United States Environmental Protection Agency (EPA) has issued new regulations for 2014 that limit the amount of carbon dioxide and other greenhouse gases emitted from diesel engines.
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Navistar offers the MaxxForce 9 for the fire service, a diesel
engine rated up to 330 hp and available in automatic and manual
configurations. (Photo courtesy of Navistar.)
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Cummins makes four engines used by the fire and emergency vehicle market, says Spencer Dell, senior communications marketing specialist. These are the ISX15, ISX12, ISL9, and ISB6.7, each including an XPI fuel system, VGT turbocharger, aftertreatment system with DPF, and SCR.
Crowel says that the integrated components of the Cummins 2013 engines deliver improved reliability, durability, and fuel economy. "Each shares a new single electronic control module (ECM) that manages the engine and the Cummins aftertreatment system for improved overall combustion efficiency," he notes.
The ISX15 has ratings from 455 to 600 hp, while the ISX12 has ratings from 370 to 500 hp. "Both engines deliver strong pulling power and throttle response and feature high-efficiency water, fuel, and lube pumps to help reduce parasitic loss and improve fuel economy," Crowel says.
The ISL9 has ratings from 270 to 450 hp and the ISB6.7 has ratings of 260 to 360 hp. Both engines have had an air intake throttle added to enhance the efficiency of the EGR system, meaning greater fuel economy, Crowel points out.
Vehicle and Engine Packages
Elissa Maurer, manager of external communications for Navistar Inc., says her company has a strong presence in the fire apparatus and ambulance market. "We offer our customers a range of vehicle, engine, and horsepower offerings," Maurer says. "Vehicle offerings are the International TerraStar, DuraStar, and WorkStar, while engine offerings are the MaxxForce 7, MaxxForce DT, MaxxForce 9, MaxxForce 10, and MaxxForce 13."
Maurer says the TerraStar's MaxxForce 7 is a V8 turbodiesel that incorporates advanced design elements and components from Navistar's commercial engines, with horsepower starting at 220. The DuraStar encompasses the MaxxForce DT, 9, and 10 engines, she says.
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The Detroit DD13 diesel engine made by Daimler
Trucks North America is configured for the fire
service with a 500-hp rating. The engine uses a
three-stage Jake Brake to extend the life of the
service brakes. (Photo courtesy of Daimler Trucks
North America.)
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The MaxxForce DT comes in automatic and manual driveline options and horsepower ratings from 215 to 300 hp. The MaxxForce 9 also is available in automatic and manual configurations and offers ratings up to 330 hp, Maurer adds. The MaxxForce 10 "has thousands of potential build configurations and offers ratings up to 350 hp," she adds.
Navistar designed the MaxxForce 13 specifically for its International WorkStar brand heavy vehicles using advanced materials and components to deliver, Maurer says, "outstanding fuel economy, excellent power characteristics, an exceptionally smooth and quiet ride, and high strength without added weight." The engine is rated up to 475 hp.
Navistar's engines are available to the fire service when purchasing International commercial chassis.
Fire Service Specific
Brad Williamson is manager of engine and component marketing for Daimler Trucks North America, makers of the Detroit DD13 configured for fire apparatus service. Williamson says the narrower profile of the Detroit DD13 in "fire truck configuration allows for better integration into a custom chassis fire apparatus, while the integrated REPTO option provides a cost-effective alternative to a traditional transfer case pump drive."
Available for custom fire apparatus only through Pierce Manufacturing through 2018, the DD13 was developed with a 500-hp rating specific to the fire truck market, he says, "and its wide power band provides exceptional drivability and performance."
Williamson points out that the DD13's three-stage Jake Brake allows the end user to select the amount of auxiliary braking based on driving style, road conditions, and terrain. "The integrated Jake Brake provides quieter operation and extends the life of the service brakes," he adds.
The DD13 uses a common rail fuel system and SCR-based aftertreatment system, which Williamson says are critical components in enabling Detroit engines to establish benchmark fuel economy performance. "The advanced design of the DD13 cooling system helps maintain more consistent operating temperatures regardless of ambient temperature," he observes. "To facilitate optimal fuel efficiency, the engine runs at slightly higher temperatures than previous designs. However, because the overall system is more efficient, the 'fan-on' time is actually reduced, which cuts down on parasitic losses for improved fuel economy."
Williamson notes the DD13 comes with Fire Commander II electronic pressure controls. "This single compact unit includes a remote display and is integrated with DDEC electronic engine controls," he says. "Fire Commander II helps maintain steady pump discharge pressure by monitoring pump requirements and controlling engine speed."
ALAN M. PETRILLO is a Tucson, Arizona-based freelance writer and is a member of the Fire Apparatus & Emergency Equipment editorial advisory board. He served 22 years with the Verdoy (NY) Fire Department, including in the position of chief.