FATIGUE STRENGTH ANALYSIS OF A FREIGHT CAR BOGIE’S SIDE FRAME

An approaches to the study of the fatigue strength of a freight car 18-100 bogie's side frame are under consideration in this article. There is a decline of the quality of the manufacture side frames and increase of the number of defects, which leads to an increase the number of accidents. The relationship of the stress intensity factor and crack length for different types of fatigue cracks (surface crack and full perforation) was introduced. The algorithm of a bogie with a crack fa-tigue calculation was introduced. The inhibition of crack growth under overloading was taking into account during cal-culation. The additional numerical calculation of fatigue strength was performed by the specialized software package. Some defects of bogie larger than 1 mm is unacceptable as it dramatically reduces the fatigue strength.