Investigation of failure factors of HOSCO۱ slab yard crane Wheels

In this study, the reasons for failure of HOSCO Steel Company slab yard crane wheels wereinvestigated. The service wheels were made of GGG۵۰ ductile iron and were produced bycasting method. Ultrasonic test was used to check the casting defects inside the wheel.Ultrasound test on ۷۰-ton wheels revealed that all samples had porosity defects. Occurrenceof fatigue phenomenon, momentary and severe stops of the crane during service have ledto the formation and growth of cracks. Fatigue results from ۵ samples taken from theselected main sample showed failure in different wheels that the fatigue limit under themaximum load was calculated to be ۱۴۳ MPa. Due to the fact that the fatigue limit in thecrane in modeling done by Catia software is calculated from ۲۲۴ to ۲۵۹ MPa, so despitethe defects of defect inside the wheel, reducing the fatigue limit has been probable.