A Short-Gage-Length Extensometer and Its Application to the Study of Crankshaft Stresses

The mathematical methods of determining elastic stresses in machine elements, particularly those of irregular contour, may be excessively complex, so resort is frequently made to approximate calculations, which tend to lose accuracy while achieving simplicity. As a result a constant effort is made to supplement the mathematical treatment with experimental methods of studying stress. In this paper, the authors describe a short-gage-length extensometer and explain its application in the determination of crankshaft stresses. This instrument meets the requirement of convenience in operation, which is so essential in assuring that it will be used for the study of localized stresses.