New Common Rail Injector Nozzle 0433171831 & Dlla146p1339 for Injector 0445120030 & 0445120218

1. 1.Influence of injector operating parameters on sealing characteristics:

Factors such as fluid pressure fluctuations under high pressure and the tightening torque when the injector is installed will cause eccentricity and inclination of the needle valve during the fit, which will affect the performance of the needle valve assembly. Due to the processing level, shape and position tolerances inevitably appear on the surface of the needle valve assembly during the processing process. The needle valve is constantly reciprocating during the working process of the fuel injector. These factors cause the needle valve to have a slight inclination relative to the inner hole of the needle valve body.

1. Temperature field and deformation of needle valve coupling:

The high fuel pressure in the gap between the needle valve coupling parts causes the elastic deformation of the needle valve coupling parts. At the same time, due to the small fit gap, the fluid has a strong viscous effect, the fluid temperature rises, and the liquid-solid heat transfer causes the needle valve coupling parts to thermally deform. The elastic deformation makes the needle valve shrink smaller, the needle valve body expand larger, and the oil film in the gap becomes thicker. The thermal deformation makes the outward expansion of the needle valve larger, the thermal expansion of the needle valve body along the radial direction makes the gap smaller, and the thermal expansion along the arc length direction makes the gap larger, when the latter is greater than the former, the oil film in the gap will become thicker, otherwise the oil film in the gap will shrink .