Diesel Injector Fuel Injector 0445110743 Bosch for BMW, Mini

The common rail system refers to a closed-loop system composed of high-pressure oil pump, pressure sensor and electronic control unit (ECU), which completely separates the generation of injection pressure and the injection process from each other, which is completely different from the previous diesel injection system driven by camshafts. It is a high-pressure oil pump to deliver high-pressure fuel to the oil rail, through the oil pressure in the rail to achieve precise control, so that the high-pressure oil pipe pressure is independent of the engine speed, can greatly reduce the degree of diesel engine oil supply pressure with the engine speed change.

The diesel common rail injection system consists of a hydraulic system and an electronic control system. Among them, the hydraulic system is divided into low-pressure hydraulic system and high-pressure hydraulic system. The low-pressure hydraulic system includes a fuel tank, a fuel transfer pump, a fuel filter and a low-pressure oil line; The high-pressure hydraulic system includes high-pressure pump, high-pressure oil rail, injector and high-pressure oil pipe; Electronic Diesel Control (EDC) includes sensors, Electronic Control Unit (ECU), actuators (including injectors with solenoid valves, pressure control valves, glow plug control units, booster pressure regulators, exhaust gas circulation regulators, throttle valves, etc.) and wiring harnesses.

The common rail pipe plays the role of distributing the high-pressure fuel supplied by the high-pressure oil pump to each injector. The diesel pressure in the common rail pipe can be maintained in the range of 130~160 MPa. The common rail pipe is equipped with a pressure sensor, which transmits the common rail oil pressure signal to the electronic control unit (ECU), and the electronic control unit implements feedback control on the PCV valve to stabilize the common rail oil pressure to the target value. The flow buffer (flow limiter) ensures that the oil supply to the injector is cut off when the fuel leakage failure occurs in the injector, and can reduce the pressure fluctuation in the common rail and high-pressure oil pipe; The pressure limiter ensures that the pressure in the high-pressure rail is quickly vented in the event of an abnormal pressure.