Failure analysis of torsion bar of projectile weaving machine

Abstract

Torsion bars are some of the most important elements used in projectile weaving machines. In this study, the fracture of a torsion bar for weaving machine produced from spring steel is investigated. Specimens prepared from the damaged torsion bars were subjected to visual inspection, hardness testing, chemical analysis, and metallurgical evaluations. The failed torsion bars had been fabricated from spring steel, and the calculated stress on the bars suggested that the steel did not have sufficient torsional strength. Examination of fractured parts showed that all fractures started at a shoulder radius due to high stress concentrations. © The Author(s) 2010.