Engines for Construction Machinery - Compliance with Regulations
Engines Construction machinery
Emissions legislation is tightening around the world but the situation is a complicated one. In Europe, Stage IIIA and IIIB have been agreed and come into force from 2006 and 2010 respectively. Meanwhile, in the USA, the Environmental Protection Agency (EPA) has already issued a Notice of Proposed Rulemaking for Tier 4 emissions control, to come into force over 2008 to 2014.
Harmonization between the two systems has been a major historical problem with engine exhaust emissions laws, timing and requirements being badly mismatched. This runs contrary to the industry aim of reducing the number of engine types needed to serve the global marketplace. Construction machinery Construction machinery Construction equipment
So what is the ultimate aim of this legislative framework? Each successive, largely equivalent Tier (US) and Stage (EU) impose ever lower limits on the volumes of gaseous pollutants - carbon dioxide and monoxide, nitrous oxides, hydrocarbons, and particulates emitted by a running engine. Construction machinery Construction machinery Construction equipment
Road to Stage IIIA Having
met the requirements of Stage II, engine producers are now working towards
the emission requirements of Stage IIIA and the first fruits of their
efforts are beginning to appear. Construction
machinery construction equipment
Perkins, for example, having invested UKЈ 10 million (US$ 18 million) in its new test center, is confident that Stage IIIA requirements will be met. A pre-production Stage IIIA engine shown at BAUMA was based on Caterpillar's Advanced Combustion Emission Reduction Technology (ACERT) system. It featured electronic engine management and a high-pressure fuel system, allied to improved combustion chamber design and new components. Construction machinery construction equipment
ACERT technology is at the center of Caterpillar's emissions effort. As the regulations became increasingly restrictive, the company determined that it needed to develop a single flexible solution that would work across the board, rather then application-specific solutions. The principle is simple: if the combustion process is controlled more efficiently, emissions are minimized.
The first of its Stage IIIA compliant engines to appear with the ACERT technology is the C18 (18.2L), which is available in five ratings from 429 kW to 570 kW. The cross flow design cylinder heads with four valves provides better air distribution in the combustion chamber and the Mechanically Actuated Electronically Controlled Unit Injection system provides multiple injection and rate shaping capability. The ADEM 4, an electronic control module, the most sophisticated Caterpillar has ever made, controls engine operation.
Common rail injection Construction machinery
For Deutz too, the need was for a standard means of achieving compliance that could be used on all its engines and across a wide range of applications. Common rail injection is the key for its range of air, oil and water-cooled engines with outputs from 9 to 960kW.
However, while Deutz believed this technology provided the best solution, it wanted to minimize the additional costs and effort that would be required from OEMs resulting from the use of a single gear-driven high-pressure pump for the injection system. It therefore developed a twin pump design, the Deutz Common Rail (DCR), which leaves the basic engines unchanged.
Daimler Chrysler meanwhile has developed three engine series that meet Stage IIIA requirements - the in-line four and six cylinder 900 (75 to 240 kW), six cylinder 457 (240 to 330 kW) and V6 and V8 457 (230 to 450 kW) series, which all feature turbo-charging with charge-air cooling and high-pressure fuel injection. Construction machinery construction equipment
Daewoo is in the process of developing engine series that meet Stage IIIA. These are the DL59 in-line six cylinder developing 199 kW, the in-line six cylinder DL08 (236 kW) and the V6 DV11 (309 kW). Once again, common rail fuel injection has been selected along with optimized engine design to achieve compliance. Construction machinery construction equipment
John Deere is also applying common rail technology to its existing Stage II compliant PowerTech engines. It expects electronic engine management, common rail fuel injection and an advanced cooling system will allow it to have compliant products well in advance of the proposed introduction dates. Construction machinery construction equipment
Another approach comes from
Volvo. It says its StageIII/Tier 3 compliant V-ACT
(Volvo Advanced Combustion Technology) engines will not only fulfill
the emission requirements but also deliver significant improvements in
engine performance.
According to the company,
V-ACT allows power and torque to be available over a broader engine speed
range, which tailors the power characteristics to the specific application
needs of the equipment. While much of the details of the new technology
still remain secret, Volvo has announced that V-ACT does not use external
after-treatmentor EGR (Exhaust Gas Re-circulation), or variable geometry
turbochargers. Instead it will use simple fixed geometry turbos. Construction machinery construction
equipment
"We are keeping it simple and not adding unnecessary complexity. That is our strength against other solutions," said Karl Tasik, chief project manager, Engine Product Development. The first V-ACT engines will feature high-pressure fuel injectors and its latest engine management system. According to Mr Tasik, the dual solenoid controlled injectors and optimized air-handling deliver the right amount of fuel at the right instant. The first V-ACT engine - the D12 - will be introduced in January 2005 and working models are currently in the field undergoing intensive testing ahead of its official launch date, said Mr Tasik. Construction machinery construction equipment
Bobcat Co. check CMO page
Skyjack Inc. check CMO page
Construction machinery construction equipment Construction machinery construction equipment
