Research On Analysis And Improvement Of Structural Strength Of High Pressure Common Rail Injector

As an important power source in many fields,the improvement of energy saving and emission reduction technology is of great significance to reducing the energy consumption of the whole society.The high pressure common rail fuel injection system can control the injection quantity of diesel fuel accurately,and it is of great significance to the heat energy utilization of the improved diesel.In recent years,in order to make the diesel combustion more fully,the common rail pressure is higher and higher,which makes the working condition of the fuel injector worse and worse.It not only bears the corrosion of the unclean diesel oil to its components,but also bears the environment of high temperature and high pressure.After reading the injector strength and sealing the literature wear injector,this paper summed up the fuel injector for diesel engine fuel supply system as an important part of the system research is not much information,Therefore,this paper selects the fuel injector produced by a diesel engine supporting enterprise as the research object to carry out the strength analysis.Fuel injector diesel engine as one of precision devices in the system,is a device will eventually fuel into the cylinder,the high failure rate will inevitably lead to frequent shutdown of the diesel engine,sufficient strength is a prerequisite for its reliable operation,so in the premise of realizing all functions of the injector,keep stable in strength harsh working environment.The contents of this paper include the following aspects:1.From the structure and working process of the injector,the failure of the injector is analyzed,and the mechanical model of the structure of the injector is established.2.From the two aspects of the needle valve couplings of the strength are analyzed,on the one hand,the theory of stress wave model to calculate the injector needle impact stress,on the other hand,to establish the simulation of fuel injection nozzle calculation model.The static strength analysis of the needle valve body is carried out by ABAQUS,and considering the complex contact process fully,the process of needle valve impact is analyzed by explicit dynamics.3.It is not a one-time impact from a needle valve,but a continuous and repeated impact in the process of work.The actual impact of the needle valve will inevitably form a stable state after repeated multiple times.In this paper,a script is used to perform multiple continuous impact analysis and select a suitable steady state parameter to evaluate the formation process of the steady state.4.The formation of the steady state is equivalent to the actual running-in test.The wear of the contact cone tends to be stable after the steady state,and the strength of the contact surface is of great significance to the long-term stable operation of the pin valve.Surface coating is an important means to optimize the surface strength of parts.In this paper,based on the brief analysis of coating materials,three kinds of materials are selected for the simulation and analysis of ABAQUS.The analysis results show that the diamond like coating can effectively reduce the surface wear and optimize the surface strength.In this paper,the strength of the injector is analyzed by means of simulation.The focus of the work is on the vulnerable parts of the injector.The simulation analysis of the surface strength optimization is made,and the whole work is of reference to the development and design of the new product of the injector.