High Quality Diesel Fuel Injector Nozzle Dlla155s529 for Deutz Tcd7.8 L6

The form of the pressure wave is directly determined by the injection process, which is the most direct perception signal of the fuel injection process. If the injector is working abnormally, the pressure fluctuation will inevitably be abnormal, so the pressure signal can be used for the fault diagnosis of the injector. Due to the complex internal structure of the nozzle and the extremely narrow space, installing a pressure sensor at the nozzle is extremely destructive to the structure of the nozzle, which may cause the injector to fail to work normally. Set the pressure sensor at the end of the connection between the high-pressure oil pipe and the injector, and use the pressure at the end of the high-pressure oil pipe to replace the inlet pressure of the injector.

As the injection duration increases, the displacement of the needle valve increases, resulting in an increase in the flow area at the nozzle and an increase in the flow coefficient of the nozzle. With the increase of the injection pressure, the opening speed of the needle valve is accelerated and the seat time is delayed, resulting in a longer duration of the injection, and an increase in the injection volume out of the nozzle, resulting in a further increase in the flow coefficient. Under the condition of small fuel injection quantity, the fuel injection pressure has a greater influence on the peak of the flow coefficient. When the fuel injection pressure is low, the peak value of the flow coefficient is between 0.20 and 0.45; when the fuel injection pressure is high, the peak of the flow coefficient The peak variation range is between 0.30 and 0.65.