The common rail injection fuel supply system consists of high pressure fuel pump, common fuel supply pipe, fuel injector, electronic control unit (ECU) and some pipeline pressure sensors. Each fuel injector in the system is connected to the common fuel supply through its own high pressure fuel pipe. The pipes are connected, and the common fuel supply pipe plays a hydraulic pressure accumulating role for the injector. When working, the high-pressure fuel pump delivers fuel to the public fuel supply pipe at high pressure, and the high-pressure fuel pump, pressure sensor and ECU form a closed-loop operation to precisely control the oil pressure in the public fuel supply pipe, completely changing the oil supply pressure with the engine speed change. Phenomenon. Its main features are as follows:
1. The fuel injection timing and fuel metering are completely separated, and the fuel injection pressure and fuel injection process are controlled by the ECU in time.
2. The fuel injection pressure of each cylinder, the starting point and duration of fuel injection can be adjusted according to the working conditions of the engine, so as to pursue the best control point of fuel injection.
3. High fuel injection pressure and pre-injection of diesel can be achieved.
Compared with gasoline engines, diesel engines have lower fuel consumption (30% lower than gasoline engines on average), and the price of diesel is lower, so the fuel economy is better; at the same time, the speed of diesel engines is generally lower than that of gasoline engines, and the torque is larger than that of gasoline engines. However, its quality is high, the noise during operation is high, the manufacturing and maintenance costs are high, and the emission is also worse than the gasoline engine. But with the development of modern technology, these shortcomings of diesel engines are gradually being overcome.
