Volvo Construction Equipment is ready to comply with tough new EU Stage IIIB and US (EPA) Tier 4 interim legislation for off-road vehicles with the introduction of a cascade of innovations in its new generation V-ACT engines.
To answer the challenge of EU Stage IIIB and US (EPA) Tier 4 interim legislation, Volvo Construction Equipment will adopt a combination of ‘in-cylinder’ and ‘external’ solutions to meet the emissions reductions targets. A new generation of the proven V-ACT engines (Volvo-Advanced Combustion Technology) offer achievements in combustion efficiency, emissions reduction and engine performance.
The new engines will feature ultra high pressure variable fuel injection systems, super efficient cooled exhaust gas recirculation (EGR), precise control of the turbochargers, powerful new EMS engine management systems and an integrated exhaust after treatment system that features a particulate filter and thermal regenerator.
At the heart of Volvo’s solution is its new generation electronically controlled diesel engines, V-ACT. As well as lower emissions, they have enhanced engine monitoring and control, and higher torque – as well as improved performance. The new units feature exhaust gas recirculation (EGR), which lowers the amount of oxygen in the combustion chamber, reducing combustion peak temperature and in doing so lowering the formation of nitrogen oxides (NOx), a key requirement of the new regulations. As tier 4 interim engines require low sulphur fuel a new cooled EGR system has been designed which allows more exhaust recirculation than the previous uncooled generation, thereby lowering NOx further.
The reduction of particulate matter (PM) from diesel engines is another target of the latest regulations. The new Volvo system uses an advanced exhaust after treatment system that reduces particulate matter by 90% compared to the previous machine series. The filter traps the particulates and temporarily holds them until there is a sufficient build up to merit ‘regeneration’. This is effectively incinerating the particulates at temperatures above 600oC using a thermal regenerator. The regeneration system used in the Volvo solution will help maximize the uptime of the machine, further supporting customers.
With such sophistication, the new generation V-ACT electronic control unit (ECU) plays a fundamental role. The new EMS version boasts a more powerful processor with the capability to support more functions than its predecessor, at higher speeds and with more control. The ECU controls the entire EGR process, managing the mix of recirculated exhaust gas and fresh air that is so crucial to reducing NOx and PM emissions, while maintaining performance and economy.
Volvo Construction Equipment is one of a select number of manufacturers that makes both engines and construction machines, tailoring the engine/equipment system for optimal efficiency. The company also benefits from the research and technical solutions developed within the Volvo Group for sister companies Volvo Trucks and Volvo Penta, as similar emissions regulations are already enforced in the on-highway equipment sector. This experience – not to mention the millions of hours of real world testing – has proven invaluable in producing off-highway engine systems that are compliant with the environmental emissions standards required of the new legislation. Whether on-highway or off: Volvo has a solution to meet our customer working requirements.
The impact of the EU Stage IIIB and US (EPA) Tier 4 interim legislation cannot be underestimated. But environmental care, better performance, improved operational economy and higher quality are the hallmarks of the new V-ACT generation engine systems, and represent an engineering achievement of the highest calibre.