Residual Stress Measurements of Retrofitted Tank Car Weldments

摘要

A series of residual stress measurements were made on two tank cars that were retrofitted with stiffener beams. The measurements were made on the tank shell exterior in the vicinity of fillet skip welds, which were used to attach the stiffener beams to the tank structure. One of the cars had been newly retrofitted ; the second car was operated for five years in revenue service after the retrofit application. The measured stresses on the newly retrofitted car were substantially higher than on the car which had seen service indicating that some shakedown of the weld stresses may occur during the service life of the car. However, significant tensile stress (on the order of 30 ksi) were measured in the vicinity of the fillet welds having a throat size greater than .25 inch.