Degree Name

Master of Engineering


Department of Mechanical Engineering


This report is aimed at providing a computerised design procedure based on Australian Standard AS1403 : 1979, 'Design of Steel Shafts for Transmission of Power' which is a metrication and revision of ASB249 : 1969, 'Recommendations for the Design of Shafts for Cranes and Hoists', which it supersedes. The presentation given in AS1403 and particularly ASB249 lends itself to computerised calculations owing to the rigorous design procedure and time required for complete analysis. The programme has the capacity to analyse shafts supported by two bearings, being either simply-supported or cantilevered and is best suited to the design of gearbox shafts. The programme may also be used to analyse drive shafts where the peak shaft torque is entered directly in the input data. Shafts with one or two gears being either spur, helical or double-helical type may be analysed. AS1403 also provides for- the design of hollow construction shafts. In keeping with modern design practice, a comprehensive array of gear and bearing fits have been provided. Optimisation in this study is aimed at developing a solution criterion for minimising the shaft diameter. Recent design practice requires reduced shaft diameters where possible in order to locate components and reduce drive inertia. Savings in material and manufacturing costs can thus be expected. Execution of the optimisation programme follows entry of all input data in the required format. Within the data arrays, all geometrical restrictions and operational requirements are detailed. The programme does not rely on the designer's need to use 'previous experience' in shaft design. Following all calculations in which the resultant geometry of the shaft has been optimised, a data sheet containing all relevant input and calculated data is produced including shaft diameters at all critical locations along the shaft. In addition, the slopes and deflections at gears and bearings are displayed with which to compare with manufacturer's recommendations. As an aid in the presentation of final shaft geometry, computer graphics has been utilised. Each gearbox shaft analysed may be displayed on a single frame in which all critical shaft diameters and relevant data are shown.