DEVELOPMENT OF A METHOD FOR WELDING QUALITY CONTROL ON CAST PARTS OF A FREIGHT CAR BOARD

The paper describes a previously unused technique for welding quality control on large-sized, cast parts of freight car bogies, in particular side frames. Side frames are cast parts made of low-alloy steel that absorb alternating loads. The analysis carried out during the research showed that the main malfunctions of the side frames for 2023 are the welding of the inner corner of the axle box opening, as well as the correction of the mark by surfacing. Correcting defects by welding within radii is permitted only at manufacturing plants with subsequent heat treatment. Visually, it is not possible to reliably determine whether heat treatment was carried out at the factory, or whether welding within R55 radii and on marks was applied under other conditions in violation of approved technologies. Due to the lack of inspection methods, a flaw detectorist at a car repair company is forced to reject the part in all cases where welding marks are detected. The work proposes to determine the presence of heat treatment by measuring the hardness of the base metal and the weld. The results of experimental studies are presented. Conclusions are drawn and tasks for further research are set.