One million Common-Rail-Systems from Bosch

[CFriedriszik]

Bosch manufactured the 1.000.000th Common-Rail-system recently
CR technology was first used by Alfa Romeo (AR 156) and then by Mercedes-Benz (C-Class). Currently CR is used by BMW, Daimler-Chrysler, Fiat-Group (Alfa Romeo, Fiat, Lancia), Iveco, PSA (Citroen-Peugeot), Renault and Audi (V8 only).

Diesel engined cars 1998 had a market share of 27 % in Western Europe, whilst the share was only 14 % ten years ago.

With the CR-system pressure buildup and injection are seperated. The pressure is generated by a continuously engine driven pump. Maximum injection pressure is 1350 and both pressure and timing of injection are selectable as needed.

Right now Bosch develops the second generation of CR with maximum injection pressures of up to 1600 bar. This second generation will be on sale at the end of 2000, when the second million of CR-Systems will be delivered.

Furthermore Bosch develops a CR-system with piezo-elements, which can react faster and can therefore be used to be kinder to the environment.

Original file: http://62.192.3.34/d/zoet_seitenanzeige.cfm?id=255&oe_plist=6&bo_feld_09=Letzte+8+Wochen&ma=Alle

Remarks: The big bonus of CR is NOT the high maximum pressure (In fact, the best rotary distributor fuel injection pump provides even higher pressure), but the high pressure that is available throughout the rev range, even at idle. And of course that the process of pressurizing the fuel is seperated from the actual injection process - the pump can be much more simple and can easily be driven by the engine.

Claus

 

[SkyPup]

Awesome! hard to believe that Bosch has already sold a million units, and none in North America, sounds similar to the original TDI engine concept.

BTW, the reason CR is better than our rotary distributor pumps is that in the CR system, the pressure is already available all the time on demand throughout the entire system. Thereby granting instaneous response without any of the problematic pressure shock wave feedback that causes the injectors to drip or pre-fire which has been such a big problem in the past. Of course, Unit Injection Pump Duse also alleviates this hassle with an injection pump on each injector, however CR technology may ultimately turn out to be the best method, especially when it is internal to the engine block guaranteeing equilivant fuel temperatures throughout the entire system (fuel mass = fuel volume X temperature change).

 

[CFriedriszik]

I do fully share your view on the further possibilities and the benefits of CR.
And just think about how easier it is to find a location for the pump with CR and that the whole system can be a lot cheaper in the end, because the only item which needs to be manufactured with ultra accuracy are the injectors.

 

[SkyPup]

Claus, here is the ENTIRE REAL INSIDE STORY OF BOSCH CR from the SAE:

Document Number: 1999-01-0191
Book Number: SP-1415
Title: Common Rail System (CR-System) for Passenger Car DI Diesel Engines;
Experiences with Applications for Series Production Projects

Meeting Where Presented:
International Congress & Exposition, March 1999, Detroit, MI, USA, Session:
Diesel Fuel Injection & Sprays (Part A&B)


Author(s):
Ulrich Flaig - Robert Bosch GmbH