RESOURCE-SAVING TECHNOLOGY OF PRODUCTION OF WELDED VESSEL MADE OF REFRACTORY STEEL 15H5M

Abstract

With, is technologically very complex and energy-intensive subsequent high temperature heat treatment of welded joints made of the apparatus. It is shown that the developed technology of welding with RTTS in automatic welding in shielding gases, welding wires austenitic heat-resistant steel 15H5M martensitic structural class allows to provide in the heat-affected zones (WJZ) obtaining bainite instead of martensite structure with high fracture toughness and at the same time homogeneous dispersion structure of austenitic weld metal. Due to the hardening of the austenite, avoiding excessive heating reduces the probability of formation of hot cracks austenit the seam, increases the corrosion resistance cracking, as when welding in layers,and the concomitant forced cooling adjustable. Thus by providing a compressed thermal cycles of welding, there occurs a reduction in the width of the active zones with a corresponding decrease in the values of residual welding stresses in the welded connection. Achieved greater generality of the grain boundaries of fine-grained bainitic ordered structure in the heat-affected areas of overheating of welded steel and the dispersed structure of the austenitic weld metal in the zone of fusion with minimal distortion of the microstructure in the fusion zone of the dissimilar joints. The introduction of the received results allows to improve technological and structural strength of welded joints, welding is used on the forced modes and to expand the scope of welding technology sabaliauskas heat-resistant steels without the use of heat treatment in the production of petrochemical equipment and pipelines, reduce the cost of welded equipment.(The purpose of developing resource-saving of technological process of manufacture of welded southwest of shielding gases in austenitic welding wires with high-temperature steel 15H5M regulation with the use of automatic welding thermal cycles (RTC). Technical and economic efficiency of the developed technological process of welding is ensured by eliminating preliminary and accompanying heating during welding to 250-350.