DEVELOPMENT OF REMOTELY-CONTROLLED EQUIPMENT AND TECHNOLOGY FOR LASER WELDING REPAIR AND RESTORATION OF PERFORMANCE OF NPP STEAM GENERATORS

摘要

Control straight butt joints of 10Kh18N10T and 10Kh17N13M3T steel blanks were welded in the vertical position with incomplete penetration by the thickness. Visual and radiographic examination, and metallographic investigations were performed, and welded joint microhardness was determined. Parameters of technological welding modes of the studied circumferential welded joints were established. Conditions of compliance with quality category "high B" of DSTU EN ISO 13919-1:2015 standard were the criterion for selection of appropriate parameters of the modes of laser welding of circumferential butt joints. As a result of work performance, it is shown that the point of welding start influences the dimensions of the weld section, in which the welding process is stabilized, and specified penetration depth is achieved. The techniques developed by the authors were verified on simulator-samples during pilot testing of the model of remotely-controlled equipment developed for repair and restoration of performance of PGV-1000M type steam generators.