Lighting And Fatigue Analysis Of R175 Single Cylinder Diesel Engine Body

Single cylinder diesel engine is mainly used in the small tractor, small generator sets, garden machinery and other industrial and agricultural production tools. Lightweight of single cylinder diesel engine body has great significance to the development of industry and agriculture and solving the problem of resources and environment. Engine block is the installation foundation of other engine agencies, bearing a variety of load. Therefore, realizing lightweight of single cylinder diesel engine must ensure that the body has enough strength and stiffness.This study takes R175 type single-cylinder diesel engine body as research object, changes the body material from cast iron to aluminum, uses the finite element method to calculate and analyze its strength and stiffness, gets the body’s stress and large deformation area, and then makes structure optimization design.This paper use Pro/E software to establish a R175 diesel engine block assemblies’ 3D model, use ANSYS software to do finite element structure analysis and get the data of body’s stress and deformation. This paper puts forward a body deformation analysis method using these data. The method mainly includes extraction and processing of the data from the finite element calculation result. Coaxality, cylindricity, roundness of each section and light-seal degree was taken as evaluation index of cavity and planeness was taken as evaluationindex of plane.The calculation results show that after transforming the body material from cast iron to aluminum, the stress changes a little, but the deformation of engine body becomes bigger. The roundness and light-leaking rate of each section in cylinder liner, coaxality and cylindricity of main bearing hole in body, cylindricity of main bearing cover inner hole, flatness of body top surface and gear room end face are increased significantly. Compared with the original body, stress concentration phenomenon of the improved cast aluminum body is decreased. Roundness and light-leaking rate of each section in cylinder liner is reduced, cylindricity of cylinder liner inner hole is decreased, so the stiffness of the body is increased. Coaxality of body top plane and cylinder liner inner hole, flatness of gear end face, coaxality and cylindricity in gear chamber cover side are increased. but under the corresponding machining precision, they can conform to the requirements of the processing on the drawings. Cylindricity of main bearing hole and inner hole of main bearing cover are beyond the drawing requirements, but the impact is not big.The comparison and analysis results show that compared with original cast iron cylinder block, the intensity of the cast aluminum alloy cylinder block with the design improvement is increased; besides the deformation in all aspects can meet the requirements of the body stiffness, so body lightweight is realized. In condition of guaranteeing the performance of engine, the body quality of 3D model declines from 6.2214 kg to 5.795 kg, the falling percentage is 6.9%.