喷油器工作可靠性研究

On Improving the Reliability of an Injector

本文用概率分析方法研究柴油机喷油器调压弹簧的工作可靠性.探讨针阀尾端和挺杆下部及针阀和阀体座面的撞击产生的应力和磨损、调压弹簧松弛、喷油嘴流通特性的变化等对喷油器性能的影响,提出改善喷油器工作可靠性的途径.

This paper reports the method of improving the reliability of an injector. In type DI diesel engines, high injection pressure and high injection rate are usually required. Coked nozzles, low nozzle opening pressure, nozzle leakage, nozzle getting stuck, and defective spring are commonly found faults. The needle seating is of utmost importance. The impact force comes from the spring under cyclic loading. Dynamic effects thus occurring cause additional stress other than those resulting from static loading. Formulae for calculating the reliability of pressure spring are derived. After honing, the standard deviation of full flow in the spray bore is significantly reduced, resulting in better injector performance.