Last month, Swedish multinational manufacturing company Volvo Trucks announced that its powertrain has now become more efficient than before as it incorporates the latest generation of Euro 6 engines and the integrated intelligent Volvo I-Shift transmission.
“Combining good driveability with fuel-efficiency is a far greater achievement than just focusing on driveability or fuel-efficiency alone,” says Volvo Trucks president and CEO Claes Nilsson.
He explains that Volvo Trucks decided to succeed in both arenas. It is, therefore, in command of the development and production process of the entire powertrain. He adds that, in this way, the company can ensure optimal integration and communication between engine and transmission, and continuously fine-tune both hardware and software to achieve the best possible balance between good driveability and low fuel consumption.
Nilsson adds that the engine is a perfect example of how several small advances together can result in a big improvement. The two most significant updates are the increased compression ratio on the D13 420 and 460 hp versions, and a new optimised turbocharger on the 500 hp and 540 hp variants of the D13 engine.
“For many of our customers, maintaining a high average speed is important in order to save time – time that may be crucial to the transport mission. In the same way, it’s important to minimise fuel costs. What we have now achieved is an engine and gearbox that utilise their full combined potential to deliver more efficient transportation,” says Volvo Trucks powertrain components: engines product manager Mats Franzén.
The company says the amount of fuel the latest improvements can save depends on the truck’s specification and application area. For a Volvo FH series on long-haul operations, fuel consumption can be reduced by up to 3%. For heavy transports, such as timber haulage, the saving may be even higher if the engine is combined with Volvo Trucks’ recently introduced I-Shift transmission with crawler gears and Tandem Axle Lift, the unique driven liftable rear axle.
Other important factors that help cut fuel consumption are the aerodynamics improvements made to the cab. Air drag increases disproportionately in relation to speed. For example, by doubling the speed, aerodynamic forces increase by a factor of four, which has a major influence on the fuel consumption of trucks.
“When we work with aerodynamic improvements, the holistic perspective is important. In order to identify those optimisation measures that do the greatest good for our customers, we’ve minutely examined every single detail of the truck,” says Volvo Trucks aerodynamics development senior research engineer Anders Tenstam.
In order to create smoother air flow, Volvo Trucks has fine-tuned the front bumper spoiler, air deflector panels, mud guards and mud flaps, as well as the wheel wells. These are all small details, which, in combination, contribute to greater customer benefit.
“Our customers constantly demand new solutions that are both productive and cost-effective. In order to meet their needs, we focus wholeheartedly on continuously improving the driveability of our trucks and, at the same time, minimise fuel consumption,” says Nilsson.
Volvo Trucks’ I-Shift is an intelligent automatic transmission, available in three versions, which selects the right gear with precise timing. In addition to the standard I-Shift version – which is available in variants for different transport applications – there are the I-Shift dual clutch and I-Shift with crawler gears. I-Shift dual clutch is a dual-clutch transmission offering seamless gear changes. Torque is maintained between gear changes, making I-Shift dual clutch optimal for transport assignments with high demands on performance, high average speed and gear change frequency. I-Shift with crawler gears was developed for heavy haulage and transports in severe applications and can handle starts from standstill with up to 325 t gross combination weight. The crawler ratios also permit driving at exceptionally low speeds.