Diesel Injector Fuel Injector 0445120083 Bosch for Yuchai King Long 5.2D Yuchai Yc4e 4.3D Yuchai Yc6j 6.5D Engine

Effect of Carbon Deposition in Injector Orifice on Injection Pressure of Diesel Engine

In this paper, the optical microscope is used to compare and analyze the difference in the nozzle hole morphology of the new injector and the carbon deposit injector. Using the fuel injection pump test bench to use the new injector and carbon-deposited injector to carry out the fuel injection test respectively, the influence of the carbon deposit in the injector on the fuel injection pressure of the diesel engine is analyzed. (1) After the carbon deposit in the injector, the nozzle exit There are a lot of carbon deposits, which are roughly distributed along the circumference of the nozzle hole in a circular arc shape. Compared with the new injector, the nozzle hole thickness is worse, and the inner roughness of the nozzle hole has increased. After the carbon deposit in the nozzle hole, the original nozzle structure is changed and the nozzle hole is blocked to a certain extent. Delay, the needle valve seat time is delayed, the fuel injection duration increases, and the residual pressure of the high-pressure oil pipe increases; the injection pressure waveform at the mouth end changes from a double-peak curve to a three-peak curve, and the second peak value increases significantly.

3) At different opening pressures of the injector, the influence of carbon deposition on the pressure at the pump end has a small difference, but the influence on the pressure waveform at the mouth end is quite different.The greater the opening pressure, the more obvious the pressure increase at the mouth end caused by carbon deposits, and the more obvious the 3-peak pressure curve.