Justification of modes of restorative heat treatment of heat-resistant steel of TPP vapour steam bent

Keywords

head-resisted steel, main steam pipeline TPP, restorative heat treatment.

Cite as

Tsybailo I. O. Justification of modes of restorative heat treatment of heat-resistant steel of TPP vapour steam bent. Physicochemical Mechanics of Materials. 2024. 60(2), 103-107.

https://doi.org/10.15407/pcmm2024.02.103

Abstract

Restorative heat treatment modes was tested to improve the microstructure of used heat-resistant steel in the stretched bending zone of the main steam pipeline of a thermal power plant. The change in the number of grains of different sizes along the pipe wall thickness after long-term operation and after additional heat treatment was studied. The mode for restoring the structure of 12Kh1MF steel was substantiated, which consisted in double normalization from 1100 and 960°C followed by tempering at 740°C. It was shown that after restorative heat treatment, the proportion of small grains increased to 55%, and of large grains decreased to 10% throughout the entire thickness of the pipe wall.

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