Estimation of sealing performance with quasi-distributed strain sensing in spiral wound gaskets

Abstract

Modern process industry, particularly (petro)chemical industry faces, many challenges pertaining to sustainability. In this respect, more stringent regulations on reducing emissions are motivating plant and process owners to implement condition monitoring and predictive maintenance strategies. Bolted flange connections equipped with sealing gaskets, for example, can be a significant source of emissions and their performance remains often ambiguous under modern standards. Gasket stress is a key performance indicator of a bolted flange connection, which is typically approximated using methods that rely on many simplifications and assumptions. This study investigates the potential of using fiber-optic sensors, more specifically fiber Bragg gratings, as strain sensors to estimate gasket stress in bolted flange connections with gaskets. To the best of our knowledge, it is the first time that said gaskets are instrumented with fiber Bragg gratings. For our experiments, we submit these gaskets to relevant mechanical loads, both in a laboratory setting and in a realistic industrial environment. We analyze the relation between the fiber Bragg grating response and the applied mechanical load to define transfer functions that allow estimating the gasket stress and hence the sealing performance of the flange connection.