Study On The Bending Strength Of Large Module Involute Cylindrical Spur Gear

Large module gear is used more and more in great engineering projects, and the module of gear is continuously augmented, for example, the module of gear of the offshore drilling platform already achieves 135 mm. In the Standard of Country GB3480-1997, the maximum of module is 50 mm, there is no expressions to calculate the bending strength of gear when the module is larger than 50 mm, whereas it is an important precondition to assure the security of transmission to calculate the bending stress of tooth of the large module gear. However, the research on the bending strength of large module gear tooth root is scarce until now. Therefore, it is significant to investigate the stresses of engaging teeth of large module gear precisely.Based on theories of gear engagement, applied two methods of bending stress analytics of gear tooth root and the bending stress FEM(Finite Element Method) of gear tooth root, the bending strength of large module involute gear was analyzed under the module from 10mm to 80mm, and the difference and trend between the results was also analyzed. The main contents and results are listed as follows:(1) A brief summary of the research of gear's bending strength and distortion is presented in this thesis. The research state of the strength analysis by means Material Mechanics and FEM is emphatically introduced.(2) The bending strength of the gear teeth is calculated by ZGCAD software which was exploited by ZRIME, and some problems of the regular computational method of bending strength are analyzed.