Failure Analysis And Improvement Measure On The High-pressure Fuel Injection Pipe

In the face of the increasingly stringent emission regulations in many countries, besides accelerating speed, lightening weight and increasing power, improving combustion and boosting oil pressure should also be taken into account to keep diesel engine's important status in traffic field. In the recent years many diesel factories assemble high-pressure pumps, aggravating vibration and advancing load stress, so possibility of trouble increasing fast, bring great loss to not only the factories but also the consumers.We take the six-cylinder diesel engines as subject investigated, base on the fact that diesel engines' possibility of trouble increases fast. We find the hazardous spots by counting failures and analyzing fatigue theory. We apply the local stress-strain experiment to measure the hazardous spots of the high-pressure fuel injection pipes' strain, periods and swing. The faults are studied by the fatigue theory and hydrodynamics. Based on the study and the Chinese standard, a new standard is established to meet the product and design of the diesel engine factory. The finite element analysis is used to create the pipe-clip model, and the working regulation and modality is studied. At last, a new method that shape of pipes and position of clips of the high-pressure fuel injection pipes is used to reduce the strain and improve the anti-fatigue characteristic. The finite element analysis is used to guide the design.The result is proved to be available by the experiment. Now the improvement is apply to products, and the information after sale indicate that the reliability is improved, and the improvement is successful.