Special Story

The Spirit to Take on Environmental Measures Tier III-compliant Engine Technology "ecot3"

A higher hurdle to clear in environmental impact reductions

While diesel engines enjoy the significant merits of high combustion efficiency and low amounts of CO2 emissions, controlling their emissions of NOx (nitrogen oxide) and particulate matter (soot and other airborne particles) has become critical with regard to environmental impact reduction. The U.S. launched emissions regulations designed to reduce NOx and particulate matter (PM) in 1996, and the U.S. and Europe's Tier III emissions regulations entered into force in 2006, along with a new law in Japan regulating off-road vehicles.

With Tier III regulations mandating emissions of only about one-third the level stipulated in the Tier I regulations of 1996, it is essential that a high level of emissions performance be achieved. Engine power, fuel efficiency, durability, reliability-the issue becomes how to meet these requirements, yet still comply with emissions regulations. The Tier III emissions regulations constituted a formidable challenge, even for Komatsu engineers.

Repeated trial and error to achieve a breakthrough

One technology key to a breakthrough was an EGR, a system that reduces NOx emissions. While the development of a new regulation-compliant engine attempted to improve upon the EGR, "improvements" to the existing model or other kinds of tweaking processes would not even begin to enable the company to achieve success. The engineers went back to the starting point and began to craft an EGR specifically designed for construction equipment diesel engines with their own hands.

The environmental conditions set for development included a temperature range from 50℃ to -50℃ and altitudes in excess of 4,000 m. In addition to that, the engine had to be able to withstand enormous amounts of dust, dirt, and sand. Furthermore, diesel engines for construction equipment should be able to respond flexibly to various grades and types of water, engine oil, and diesel fuel and still generate sufficient engine power. It was necessary that this tremendous obstacle be overcome for the sake of conserving the global environment.

The development of cutting-edge technologies involves patient and repeated trial and error. Without convictions, it is impossible to continue to push forward. Running through a cyclical process of drawing blueprints, creating experimental models, running tests to evaluate them, and analyzing the results, the engineers bounced opinions off each other around the clock. Taking a meticulous approach to the materials and shape of each individual component, the "Heavy Duty Cooled EGR" was finally deemed finished, drawing a clear connecting line to previous technologies. Through the combination of these technologies, the revolutionary engine technology "ecot3" was born, cutting emissions of both NOx and PM simultaneously while reducing fuel consumption.

Beyond the goal lie still more stringent new targets

Komatsu's insistence on originality stems from the importance of differentiating itself from its competitors through the in-house development of a major component such as an engine. Yet beyond that lies the benefit of reducing the development time of a vehicle. Supporting that is the pride of Komatsu's engineering team, which creates the best construction equipment on the globe with their own hands.

Under the Tier IV emissions regulations entering into force in 2011, which mandate the reduction of emissions to a level about one-twentieth of 1996 levels, even more advanced feats in engine development will be necessary. Komatsu's engineers have already launched their work with 2011 squarely in their sights in order to clear this higher standard.

  • IPA Managing Director
    Tohru Okazaki

    A diesel engine for construction equipment requires a number of original technologies. Our engineers are all proud to be involved in the development of these engines.

  • IPA Engine Development Group
    Hatsuo Andou

    I invested some three years in finding the best way to bring conflicting elements together to coexist and then determine how to fine-tune the design.

  • IPA Control Development Group
    Takashi Sakasai

    For Komatsu, having such strengths in technology, emissions regulations are just a further push in the same direction. If we worried that it would lead to a step back for us, there would be no technological progress at all.

  • IPA Combustion & Fuel System Group
    Yoshiki Kanzaki

    I chose this job because I've always liked construction equipment ever since I was a little boy. I have been involved in this project since immediately after I joined the company, so I'm extremely fond of this engine.

  • IPA Testing Group
    Akira Kusakabe

    To ensure quality, evaluation tests constitute an absolutely essential process. In these tests we had to be particularly attentive to the fact that, among other things, regulation values and conditions in Japan, the U.S., and Europe are slightly different.

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