Evaluating the Damage Mechanism Characteristics for Tower Crane Pulley Using Magnetic Flux Polar Mapping Distribution

Abstract

This paper investigates the high stress concentration zone for fatigue crack estimation on the damaged tower crane pulley by measuring magnetic flux leakage. Fatigue crack analysis is important to prevent any component failure that could harm workers. Precautions must be taken to locate the possibilities of failure region on a tower crane pulley. For this study, magnetic flux leakage signals were measured using metal magnetic memory method to predict the high stress concentration area. The respective signals were collected for 30 scanning lines on the tower crane pulley surface and merged to provide a better graphical view to estimate the irregularities or defect location more accurately. The metal magnetic memory polar mapping was compared with the finite element analysis results for validation. The highest von Mises stress value obtained through the finite element analysis is 167.84 MPa using three-dimensional tetrahedral mesh for the size of 3 mm. Thus, the comparison revealed the similarities of stress concentration zone between the results and will produce more accurate prediction for the actual irregularity or defect location on the failed component.