Evaluation of the state for the material of the live steam superheater pipe coils of V degree

The main purpose of the undertaken research was to evaluate the state of the material of V degree live steam superheater pipe coils made of 10CrMo9-10 (10H2M) chromium-molybdenum steel as well as to determine their usability for further operation. The pipe coils came from a steam boiler working at a power plant. The scope of the research included: working out the functioning of a sampling strategy and a preparation procedure of the samples, microstructural tests with the use of a light microscope and a scanning electron microscope, and finally, the conclusions drawn on the basis of the performed tests and the literature review. The work presents the types of steel of which the mentioned elements were made as well as analyzes their working conditions. It describes the most often observed causes of pipe coil damage and presents techniques of controlling the proper efficiency and usability of these elements for further operation.