Preliminary Design of a Power Transmission Shaft under Fatigue Loading Using ASME Code

Abstract

Power transmission shafting is a vital element of all rotating machinery. A complete shaft design involves many iterative phases and fundamental to this is the determination of preliminary dimensions of the shaft. This paper presents a comprehensive fatigue analysis approach of determining the initial dimensions of a power transmission shaft under fatigue loading based on American Society of Mechanical Engineers (ASME) Standard B106.1M:1985. A countershaft running at a constant speed is designed using this approach. Stress analysis at potential critical locations are conducted to determine the shaft sizes. The sizes from these locations are then used to estimate the sizes at low stress locations. Adjacent sizes are blended using the largest size. To help visualize, a CAD model of the preliminary designed countershaft is provided.

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