Bosch Common-Rail Systems
Bosch Common-Rail Systems

Sept 04, 2012–Gerlingen,Germany (Techreleased) –Bosch common-rail systems for marine applications. In the form of three different common-rail injection systems, Bosch technology is also to be found on the world’s waterways and oceans. From yachts to container ships and cruise liners, they cover every marine application. This makes Bosch the only company that offers the entire range of common-rail systems – from passenger cars to commercial vehicles to large-scale diesel engines that develop more than 21 megawatts of power and that are used in locomotives, generators, and ships. To comply with tomorrow’s stricter standards for pollutant emissions, Bosch is working on systems with higher injection pressures. Both the common-rail system for heavy oil and the MCRS-T marine common-rail system for conventional diesel fuel will work with a higher injection pressure of 2,200 bar in the future. This will allow better consumption values, and thus a reduction in running costs. It will also enable compliance with future emissions standards such as EPA Tier 4 (from 2015) and IMO 3 (from 2016).

MCRS modular common-rail system for container ships and cruise liners
The extremely robust common-rail system for heavy oil has been developed for marine applications such as container ships, freighters, ferries, and cruise liners. Designed as a modular system, it is suitable for engines with an output of 200 to 1,200 kilowatts per cylinder and a displacement of five to 120 liters per cylinder.

Starting from 2016, ship’s engines will have to meet stricter requirements for pollutant emissions. With its common-rail system for heavy oil, which works at a maximum injection pressure of 2,200 bar, Bosch has a solution that will allow engines to comply with the IMO 3 emissions targets. Each of the injectors features a high-pressure accumulator, a safety flow limiter, and a solenoid valve that also permits multiple injections. The system is especially flexible in view of its potential applications.

MCRS-T modular common-rail system for barges, small freighters, and yachts
The MCRS-T modular common-rail system has been developed for barges, small freighters, and yachts. It is used in high-speed and (with correspondingly larger solenoid valves and nozzles) medium-high speed diesel engines with more than 2.5 liters of displacement per cylinder and engine power of 1,500 to 3,500 kilowatts. The marine diesel common-rail system currently works at 1,600 bar, but is to be modified to work at injection pressures of 2,200 bar to make it easier to fulfill future emissions regulations. Like the heavy-oil system, it does not need a rail or separate high-pressure accumulator. Instead, the fuel accumulator volume in the MCRS is integrated into the high-pressure pump and the injectors.

This makes it easy to adapt the modular system to different numbers of cylinders – from 6-cylinder in-line engines to V20 engines. The system ensures that the pressure at the tip of the nozzle is constant and independent of engine speed. The injectors allow up to three injections per combustion cycle. In combination with the high injection pressure, these multiple injections make it possible to achieve better values for emissions and consumption, to treat exhaust gas more precisely, and to reduce engine noise.

CRSN3 for yachts and smaller ships
For ship’s engines with an output of 100 to 200 kilowatts per cylinder, Bosch offers its CRSN3, derived from commercial-vehicle systems. For marine applications, the maximum possible injection amount has been increased in order to meet the demand for greater power. In the CRSN3, which is used in yachts and smaller freighters, the maximum injection pressure is 2,500 bar. Both the CRSN3 and the MCRS can be used in dual-fuel engines as a pilot ignition system for CNG operation.

Apart from fuel-injection technology, Bosch also supplies control units for marine engines. The EDC17CV41 engine control units, which have been modified for marine operation, control the common-rail functions and, as an option, the exhaust-gas treatment systems downstream of the engine. Apart from this, Bosch offers a great number of sensors that are compatible with these engine control units and are therefore suitable for marine applications.