Development of Welded Elements of the Railway Freight Car Bogie with Increased Characteristics of Fatigue Resistance and Survivability

In last years in the railroad territory of 1520 mm accidents have often occurred due to the destruction (failure) of the casting elements of three-element freight car bogie. The quality and durability of load-bearing elements, which is traditionally produced by casting technology, is insufficient. The development of new welded designs of the load-bearing elements were carried out on the basis of wide use of mathematical modeling to determine the stress-strain state of the welded elements under the action of regulated loads and to make the assessment of strength according to Ukrainian standards and current world approaches. The accelerated fatigue tests on prototypes were carried out, which showed that the service life of the welded structure of the side frame is ten times longer than the service life of the cast structure, and its survivability is longer in several times.