New Injector Nozzle Dlla148p1067c 0433171693 OE 93342272 2p0130201 for Fuel Injector 0445110081 0445110231 0445110336 0445110337

When the needle valve pair is working, the viscosity and lubricity of diesel oil are used to form the thickness of the oil film, which has a great influence on the service life and working quality of the pair. If the oil film in the gap is too thin or discontinuous, the load capacity will be reduced, the frictional resistance and loss between the couples will increase, and the friction pair will be prone to wear and even seal failure; when the oil film in the gap is too thick, the fuel leakage will increase, resulting in fuel The pressure is reduced, and even the fuel pressure required by the performance of the diesel engine cannot be reached. Therefore, the characteristics of the oil film in the gap between the needle valve coupler have a great effect on the lubrication and sealing of the needle valve coupler. There are two important parts where the needle valve couple plays a sealing role, namely the gap oil film and the sealing cone surface of the needle valve couple. The two ends of the oil film in the gap between the needle valve coupler are the high-pressure inlet port and the low-pressure outlet port respectively. The high-pressure inlet port is connected to the common rail pipe through the high-pressure oil passage, and the low-pressure outlet port flows back to the fuel tank through the oil return passage. During the mutual movement of the coupling parts, the fuel in the annular gap of the coupling parts forms a lubricating oil film on the sealing surface of the needle valve. Since the lubricating oil film is subject to relatively large viscous resistance in the mating gap, it not only ensures good lubricating performance of the needle valve assembly when it is working, but also reduces fuel leakage.