Failure Analysis of Repair Welded Shafts

Of all industrial machine components, shafts are among the most likely to be weld repaired rather than replaced. Weld repairs can be the cause or a significant contributor to the ultimate failure of shafts, even when repairs are high quality. Poor quality weld repairs can result in rapid or even immediate failure once service is resumed. Shaft welding repairs are not always performed by the original equipment manufacturer, so the engineering scrutiny that went into the initial design is not always reflected in subsequent repairs. Commercial failure analysts encounter a great number of shaft failures from all industries, and welding repairs are important in many of these cases. This paper discusses the failure analysis concerns surrounding weld repaired steel shafts.