INVESTING about $130 million in researching and developing a new combustion system for the new JCB Ecomax T4 4.4L engine demonstrates the company's commitment to meeting the up-coming Tier 4 interim/Stage 3B emissions legislation.
JCB says the initiative, currently undergoing full in-field testing before going into production in 2012, offers users reduced fuel consumption, reduced cost of ownership and better reliability.
Meeting Tier 4 emissions legislation without the need for any exhaust after treatment is a massive challenge but also a huge opportunity for innovation, according to JCB’s director of engine programmes Allen Tolley.
Claiming to have the off-highway sector’s cleanest engine, he said JCB’s strategy also had been to meet Tier 4 interim emission standards without using a Diesel Particulate Filter (DPF).
Quite apart from space constrictions in a modern engine compartments, JCB maintains DPFs translate into a significant reliability risk, as evidenced by automotive sector experience.
To achieve the next round of emissions regulations, JCB Power Systems has worked closely with research and development specialist Ricardo, using computational fluid dynamics, finite element analysis and a Ricardo designed combustion bowl to perfect the combustion process.
With second generation common rail fuel injection technology, injection pressures have been raised to 2000 bar and nozzle hole geometry has been refined to provide highly effective atomisation and distribution of the fuel within the cylinder.
As well, JCB has incorporated variable geometry turbochargers on all but the lowest powered 55kW (74hp) Dieselmax engine, which falls under a slightly different emission regulation.
Cooled Exhaust Gas Recirculation (EGR) is also used to clean up the exhaust gases before they are passed from the engine.
This means there is no requirement for any exhaust after-treatment components to meet these emissions levels on the 4.4L JCB Ecomax T4 engine.
The company has worked with fuel system and electronics specialist Delphi to develop an electronic control system with a form of learning capacity that will ensure the engine stays within its intended parameters even as the components settle throughout their design life.
With no need to fit an exhaust after-treatment system, there has been no requirement to increase the cooling pack size, or to reduce service intervals from their standard 500 hours.
In addition, under test conditions, the engines have been achieving a 5-10 per cent fuel consumption improvement compared to the previous generation.
The engine design is also future-proofed as the structural architecture, the componentry and systems will remain the same for Stage 4/Tier 4 Final regulations in the future, at which time exhaust after-treatment for NOx reduction may be unavoidable.
JCB has invested heavily in its Power Systems business in Derbyshire, UK, to meet the latest legislative demands.
The original 4.4L Dieselmax 444 engine has been joined by a 4.8L Dieselmax 448 version, while power ratings have been extended at both ends of the scale.
The latest investment sees the opening of one of the most sophisticated engine test cells currently in operation in the United Kingdom.
JCB Power Systems has built 10 test cells, and will initially operate six cells.
Each cell is capable of carrying out the full EU transient test cycle that is required to meet Stage 3B and Tier 4 Interim legislation.
Email a friend