Abstract
Background of the research presented is the undoubted fact that industrial boiler maintenance is essential for efficient operation and preventing failures. Traditional stress measurement methods for hanger rods (with hydraulic pressure pump) can be unreliable due to operator subjectivity. Therefore, the objective is to introduce a more accurate method for measuring the stress state of hanger rods in industrial boilers using fibre Bragg grating (FBG) sensors. The study compares traditional hydraulic pressure pump measurements with FBG sensors, which allow continuous strain measurement without shutting down the boiler. The new approach follows from the fact, that FBG sensors have been used in structural health monitoring but not in this specific application. The experimental strain measurements have been conducted on an industrial boiler hanger rod in an operational facility. The FBG sensors provided more reliable and continuous measurements compared to the hydraulic pressure pump method. After the analysis of the results obtained it has been clear that the use of FBG sensors offers a promising new approach for continuous strain measurement in boiler hanger rods, contributing to the development of diagnostic methods for estimating stress levels in industrial boilers, what is a promising conclusion.