ON THE CONTEMPORARY SINTAP APPROACH AND ITS APPLICATION TO THE EVALUATION OF THE SERVICEABILITY OF WELDED JOINTS OF STEAM PIPELINES OF THERMAL POWER PLANTS

摘要

The SINTAP approach is used for the evaluation of the serviceability of a welded joint after approx 19 10~4 h of its operation in the steam pipeline of a thermal power plant. The characteristics of strength and crack resistance required for calculations are determined on specimens cut out from the corresponding zones of the investigated welded joint. It is assumed that the welded joint is loaded by a uniform tensile stress, that residual stresses are also present in the metal of the weld, and that a semielliptic crack propagates in the base metal and the metal of the weld from the external surface of the pipeline. The theoretically established parameters of the critical state of a pipe element with welded joint are in good agreement with the expert conclusions concerning the causes of failure of the pipeline.