What is a common rail system?

The common rail system refers to the closed-loop fuel supply composed of diesel oil from the fuel tank, sucked out by the gear pump, through the oil-water separator, through the gear pump, to the fine diesel filter, to the high-pressure pump, common rail pipe, fuel injector, and sensors and ECU. System, a fuel supply method that completely separates the generation of injection pressure and the injection process from each other.

Principle

The common rail pump delivers high-pressure fuel to the public oil supply pipe (common rail pipe), and the ECU controls the opening of the flow electromagnetic regulating valve of the common rail pump to precisely control the oil pressure of the common rail pipe, so that the pressure of the high pressure fuel pipe It has nothing to do with the speed of the engine, so it overcomes the defect that the oil supply pressure of the diesel engine changes with the speed of the engine. The ECU controls the fuel injection volume of the injector, and the fuel injection volume depends on the pressure of the fuel rail (common fuel supply pipe) and the opening time of the solenoid valve.