Bosch Common Rail Systems
Lower fuel consumption – lower emissions
Robust and powerful
· CRS2-18-OHW tailored to the specific requirements of the off-highway segment
· CRSN3.3 for on- and off-highway applications
· Cost-effective high-pressure pumps with up to 1,800-bar injection pressure
Bosch diesel-injection systems deliver low pollutant emissions and reduced fuel consumption for commercial vehicles. At the same time, Bosch is designing and manufacturing powerful, robust Common Rail Systems for the specific requirements of the off-highway segment – in other words, for agricultural and construction machines as well as industrial applications.
Based on the series-production Common Rail Systems CRS2-11-OHW with 1,100 bar and CRS2-16-OHW with 1,600 bar, Bosch is currently developing the Common Rail System CRS2-18-OHW with a system pressure of up to 1,800 bar. The system operates with a new injector featuring a pressure-balanced solenoid valve and an additional rail volume built into the injector. Compared with the previous generations, the customer benefits from lower fuel consumption with a similar reduction in CO2 emissions. As the injection pressure increases within any one emission class, the effort involved in exhaust-gas treatment is reduced. The system thus helps meet future emissions limits. By tailoring the product to off-highway operation, Bosch has managed to factor in specific requirements, such as service life, fuel compatibility and the harsh operating conditions. Thanks to its modular design, the solution can be integrated easily into existing and new engine series. The product is aimed at agricultural and construction machines as well as industrial applications which develop up to 130 kilowatts with 4-cylinder engines and a maximum 200-kilowatt power output with 6-cylinder models. However, it can also be used as a cost-effective solution in light and heavy-duty commercial vehicles. The CRS2-18-OHW series will go into series production in mid-2012.
CRSN3.3 with 2,000 to 2,500-bar system pressure
The Common Rail System CRSN3.3 has been designed for the off-highway and commercial-vehicle segments. The solution is aimed specifically at engines with between four and 16 cylinders, developing between 200 and 560 kilowatts. Based on the current 1800-bar injector, Bosch has meantime configured the CRSN3.3 for injection pressures between 2,000 and 2,500 bar. The CP4 high-pressure pump, which has been derived from passenger-car applications, is used to build up the pressure and operates in tandem with high-pressure pumps from the CPN5 family. Despite the higher system pressure, the high-pressure pumps require the same or even lower drive power, thus increasing system efficiency. Thanks to the high injection pressures, CRSN3.3 will in future also meet the Tier 4 emissions standard, which is set to become the benchmark in the off-highway segment. The customer will also benefit from a reduction in fuel consumption and CO2 emissions. Both figures can be reduced even further by combining the technology with SCR exhaust-gas treatment.Cost-effective high-pressure pumps for Common Rail Systems
In light of future emissions standards, automakers and engine manufacturers are currently switching many engines from the in-line pump design to Common Rail Systems, particularly in emerging markets such as China and India. In response, Bosch has developed the CB high-pressure pumps, which can be fitted to existing units as well as new engines without any major modifications. At the same time, the development of these pumps took particular account of the frequent problem of inconsistent fuel quality in these regions. The cost-effective CB family includes the oil-lubricated high-pressure pumps CB08, CB18 and CB28. The CB08 can be used in Common Rail Systems with up to 1,600 bar pressure and a maximum engine output of 60 kW. The two variants available (with and without pump housing) enable the pump to be easily fitted to existing units. The CB18 is designed for systems with up to 1,600-bar pressure and maximum engine output of 100 kilowatts, while the CB28 supports up to 1,800-bar pressure for engines developing a maximum of 200 kilowatts.