The structural-mechanical state of 12Kh1MF steel of HPP pipeline bend after long-term operation

Keywords

head-resistant steel, bends of the main steam pipelines, degradation, mechani­cal characteristics, structure, fractography.

Cite as

Tsybailo I. O., and Krechkovska H. V. The structural-mechanical state of 12Kh1MF steel of HPP pipeline bend after long-term operation. Physicochemical Mechanics of Materials. 2023. 59(3), 67-73.

https://doi.org/10.15407/pcmm2023.03.067

 

Abstract

The mechanical characteristics and structural features of the heat-resistant 12Kh1MF steel after long-term operation in a bend of the TPP (thermal power plants) steam pipelines were analyzed. The change in the technical state of the metal of different zones of the bend was established and the anisotropy of properties across the section of the pipe wall were revealed. It was found that in the stretched zone of the bend near the outer surface of the pipe, steel degraded more intensively, which was due to the most favorable operating conditions for creep.

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