Aging management of dynamically loaded pipelines

In the Russian Federation the requirements for aging (life) management of pipelines which in the designs of nuclear power plant (hereinafter - NPP) units in accordance with the federal norms and rules in the field of nuclear energy use to the elements of 1, 2 and 3 safety classes, are established in NP-096-15. One of the most “dangerous” loading factors for dynamically loaded pipelines of NPPs is vibration loads as for real structures of NPP pipelines the values of corrosion-erosion wear are not high due to the use of corrosion-resistant steels and limitation of the flowing medium velocity (according to NP-068-05 water velocity is up to 5 m/s, and steam and gas is up to 60 m/s). The issues of aging management of dynamically loaded pipelines are considered. The use of calculation-experimental method is proposed to determine the stress-strain state of the pipeline under vibration impact in order to determine the damageability under cyclically repeated loads. It is recommended to use the values of accumulated and ultimate damage rather than standardized frequencies or vibration amplitudes as a resource characteristic under vibration loading of the pipeline.