Establishment Of Diesel Engine Key Iron Residual Stress Model And Research Of Stress Energy Efficiency And Reliable Processing

The casting residual stress of the castings has effect on their mechanical properties. It is very important to get the casting residual stress distribution and elimination the casting residual stress of the castings.In this paper, X-ray diffraction and blind hole methods were used to measure residual stress of typical castings such as engine body and cylinder head and analyze the changes of residual stresses before and after heat treatment. Residual stresses of typical iron castings were obtained by FEM numerical simulation, and to compare with actual measurement results. The research results will provide scientific basis for the minimum stress casting and the optimization heat treatment process.X-ray diffraction method and the blind hole method were utilized to test the residual stress of casting and annealed state of cylinder head, GEVO16 engine block and the front-end integrated cabinet. Through the analysis of the measurement results, we can obtain the residual stresses of cast state of GEV016 engine block are larger and distribute uneven, the tensile stress is the main, and the maximum residual stress value about 90MPa. After annealing, residual stress of GEV016 engine block significantly reduced, the residual stress values mostly within 50MPa, and the compressive stress is major and distributes more uniform. The finite element simulation method was used to simulate the temperature field, solidification fraction and stress field of cylinder head and engine block GEV016. It is obtained maximum residual stress in the cylinder head was about 56MPa and the maximum residual stress of GEV016 engine block was about 70MPa. According to the elastic-plastic mechanics theory, the model of deformation processing caused by residual stresses was built. Through simulation, it is estimate that the body’s largest security residual stress is 95MPa, and the maximum safe residual stress value can be considered as important reference for typical diesel cast iron machining distortion issues. Shorten the annealing time from 13 to 6 hours. Using improved process of shorten the annealing time, the range of residual stress in the surface of the body is 0-50MPa, the size of the residual stress within the scope of safe stress value, and the value is relatively small and more evenly distributed. It can shorten the annealing time, improve work efficiency, and reduce energy consumption and pollutant emissions.