The difference between the high-pressure common-rail high-pressure injection pump test bench and test bench
The difference between the high-pressure common-rail high-pressure injection pump test bench and test bench common rail system with the main difference lies in the diesel injection system . Prior to the camshaft drive system and the common rail diesel injection systems, common rail diesel injection system injection pressure generation and injection process is completely separate from each other . Solenoid valve injectors replaced the traditional mechanical injectors, the fuel pressure in the fuel rail consists of a radial piston high-pressure pump generates regardless of pressure and engine speed can be set freely within a certain range . The fuel pressure in the common rail by an electromagnetic pressure control valve according to the engine work requires continuous pressure regulation. The role of the electronic control unit injector pulse signal on the control solenoid valve fuel injection process . Depends on the amount of fuel injection in the fuel rail pressure and the length of time the solenoid valve opens and the nozzle flow characteristics . Fuel injection pressure is an important indicator of a diesel engine as its connection with the engine power , fuel consumption, emissions and the like. At present, the common rail diesel fuel injection system has been increased to 1800 bar injection pressure .
In recent years, direct-injection diesel engine matched cars in Europe has been a significant development , with high efficiency and excellent fuel economy and reduced engine noise . Direct injection diesel engine using a pump nozzle systems , domestic production 1.9TDI Bora on the application of this system , the maximum injection pressure up to 1800 kPa . Pump nozzle injection system is good is good, but can not maintain a constant fuel pressure , along with more stringent emission controls , you need a higher and constant pressure diesel injection and improved electronic control , so many manufacturers took advantage of more multi- diesel common rail system as the direction of the diesel engine. This system has a high fuel pressure , and to provide flexible control of fuel distribution , fuel distribution flexibly controlled by ECU, fuel injection timing , injection pressure and injection rate . Through the above characteristics controlled common-rail diesel engine has made responsiveness and driving comfort level reached petrol engine , while it has a significant fuel economy and low emissions characteristics.
Ensure a high fuel pressure in the engine speed range of all high injection pressure can get good combustion characteristics at low speed conditions .
Controlled by a camshaft drive of the axial piston engine type dispensing pump , the fuel system pressure with a linear relationship between engine speed , fuel pressure in the insufficient formation of low engine speed , and the system can get very common rail at all the speed range of the engine high fuel pressure. Flexible electronic control system controlling the injection pressure and timing of the various conditions of the engine are able to achieve low emissions and high efficiency. Due to the pressure of the formation and separation of the injection process , the engine designers to achieve greater freedom in the study of combustion and injection process . When the injection pressure and the injection can be adjusted according to the engine operating conditions being required to make the engine speed conditions for complete combustion can be achieved , even in the low speed high torque can be obtained . Application of pre-injection technology has made greater progress in reducing emissions and noise .