Goncharov P. Technology of arc spot welding of low alloy steels in vertical position

The thesis is devoted to development of technology of arc spot welding (ASW) of overlapped joints of low alloy steels in vertical position. In the work the new technological approach was developed and the equipment for its realization was created to produce arc spot joints of structures of face elements of 1.5…5.0 mm thickness in vertical position. The mathematic model of ASW was offered, which allows decreasing the volume of experiments at selection of optimal parameters of mode of arc spot welding in vertical position and evaluating performance of spot welded joint at static and alternating loads. It was established, that due to alternation of heating and cooling stages of welded joints the refining of metal structure occurs and hardening structures in welding of low alloy steels of the type 09G2S are absent. The practical recommendations for use of the offered ASW technology were developed. The efficient methods for diagnostics of quality of the produced spot joints using method of electron shearography were offered.