Choice of emission control

Functions, advantages, and disadvantages

The environmental requirements of emission legislation in the EU and the USA have led to the development of two different types of emission control technologies: CEGR and SCR. In the two films here we take a look at how each technology works and how they fulfill the needs of modern forestry. A little further down the page you can also see which engine technology each machine manufacturer has chosen, for harvesters, forwarders, and trucks.

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How has the market chosen?

The choice between the traditional EGR/CEGR technology and the refined SCR technology currently divides the forest machine industry into two camps, with all machine manufacturers except John Deere and Rottne having chosen the technology where NOx reduction takes place after and outside the engine's combustion process. This enables the combustion process to be optimized, reducing particulates and ensuring maximum engine performance. Even among truck manufacturers SCR technology is clearly dominant:

The new engine generation

SCR is an emission control technology that enables the construction of highly efficient engines able to deliver high performance, high torque, and lower fuel consumption. The exact same advantages that characterize Komatsu Forest's latest generation of engines.

Higher injection pressure

Thanks to the latest generation of common rail injection systems, one can attain higher injection pressure, more accurate timing, and more effective air charge cooling. This provides a strong engine, rapid engine response, low particulate emissions, and – not least – low fuel consumption.

Computer control and electronic control

The new generation of fuel injection systems, which is computerized and electronically-controlled, enables the engine to react faster and without delay to changes in load, and the injection system optimizes the pressure regardless of operating conditions. The result is a more responsive engine.

High torque and low fuel consumption

The engines have two inlet and two outlet valves per cylinder. This enables increased fuel flow and a reduction in pump losses. This means lower emissions and lower fuel consumption. Tests have shown that in favorable conditions diesel consumption can be reduced by more than 20 percent. Further advantages are lower engine noise, high reliability, simple service, and high torque even at low engine speeds. This enables the machine to work as effectively as possible regardless of operating conditions.