Delphi ups the pressure
By Steve Skinner10 December 2008
Delphi has launched its first common rail fuel injection system for engines in the medium to heavy duty construction equipment sector.
“Combining the flexibility of our rail based fuel management with the ultra high pressures that Delphi has achieved with our electronic unit injection (EUI) technology, the new remote pump and distribution pump common rail systems will provide a highly effective and affordable path right through and beyond Stage IV/Tier IV Final compliance,” said David Friday, general manager at Delphi diesel heavy duty.
The new system is available with a conventional common rail architecture, in which fuel pressure is provided by an engine oil-lubricated remote cam-and-plunger pump, developed by Delphi from its established medium duty common rail technology, and in two distributed pump architectures.
The first of the distributed pump architectures, known as F2P, is ideal for cam-in-block engines that would traditionally have used an electronic unit pump (EUP) architecture. The same layout and dimensions can be retained, with two or three cam-driven pumps, depending on engine rating, and dedicated injectors using new high-precision outlet metering valve technology.
The second of the distributed pump architectures, known as F2, is ideal for cam-in-head engines that would traditionally have used EUI architecture. Again, these can retain their existing layout and dimensions, using two or three cam-driven combination pump/injector units.
“These highly sophisticated devices use a patented miniaturised valve to close the path to the nozzle when pressure is being directed to the rail,” said Mr Friday. “When fuel is required at the nozzle, the pumping element is isolated and fuel is directed from the rail to the outlet metering valve.”
Delphi has spent almost five years refining the technology and much of the knowledge used builds on experience gleaned from the company’s twin valve E3 EUI, which operates at 2500 bar.
Both the remote and distributed pump common rail systems are available with specifications optimised for medium duty (4 to 9 litre engines) or heavy duty (9 to 16 litre engines) applications, delivering 2400, 2700 and 3000 bar respectively.
Delphi is already working on common rail development programmes and anticipates production will commence in 2012, prior to the introduction of Stage 4 emissions legislation in 2013.
See January’s edition of Construction Europe where Steve Skinner looks at developments among the off-highway engine manufacturers as they work towards meeting Stage IIIB/Tier IV interim compliance.