Development of Shaft Strength Calculation Macro in Microsoft Excel: A Practical Guide for Engineering Students

In the field of mechanical engineering, shaft strength calculations are crucial for creating reliable and efficient machinery. Traditionally, these calculations are done manually, a process that can be time-consuming and prone to mistakes, which can lead to design issues. To address these challenges, a practical guide is available to help engineering students develop a gear calculation macro in Microsoft Excel, transforming a complex and error-prone task into a streamlined, automated one. The guide begins by providing a solid understanding of fundamental gear mechanics concepts, ensuring that students are well-versed in the principles before diving into Excel's technical aspects. The analyzed shaft, manufactured from S45C steel, is a keyed shaft designed to handle a bending moment of 502.8 N·m and an output torque of 260 N·m, with no thrust load (Fa = 0 N). The shaft has a diameter of 28 mm and a stepped section with a maximum diameter of 35 mm, including a radial dimension of 3.5 mm for smooth transition. A keyway of 8 mm width and 4 mm depth is machined to ensure effective torque transmission. The material’s tensile strength is 686 N/mm², with a factor of safety (SF) of 1 applied to the design.