FEATURES OF USING SPRING INSERTS FOR REPAIRING INTERNAL THREADS IN HOUSINGS OF PASSENGER CAR BOXES

The paper discusses actual problems of repairing damaged threaded holes in box housings of passenger wheelsets. The reasons for the occurrence of thread defects are analyzed, in particular, in the holes for sensors of box heating control system (BHCS). The study objective is to substantiate the expediency of applying repair technology using spring (spiral) threaded inserts as the most efficient, technologically advanced and reliable method. The task to which the paper is devoted is the search and justification of a technological, cost-effective and reliable method of repairing damaged threads for sensors of box heating control system in box housings of passenger cars, which can be implemented directly in the depot without dismantling the entire assembly and thermal impact on the part. Research methods are analysis of statistical data obtained during the inspection of the rolling stock fleet (survey of 1098 box housings); comparative analysis of existing methods of repairing threaded connections (welding, cutting repair threads, installing screwdrivers); technical and economic analysis of the costs to replace and restore box housings. The novelty of the study is the adaptation of this method for implementation in a railroad depot. The main stages of the technology, advantages of the method and an assessment of its economic efficiency are presented, confirming the expediency of using spiral inserts in depot conditions.