Sometimes an industrial component can be affected during its life by several external and internal conditions that can induce failure modes, or at least, contribute to the presence of one or more symptoms that can cause a certain amount of stress in the component and therefore facilitate the development of such failure modes. This paper presents a new maintenance model guided by a non-overpass of a stress threshold for a component according to its health condition and technical and economical feasibility. This new maintenance model will help to reschedule the programmed maintenance in a dynamical form according to the life evolution of the industrial component analysed. Stress, as defined in this paper, is a concept based on the deviation between the real behaviour observed and the normal behaviour expected in a component for the evolution of variables according to the working conditions. Once evaluations of the levels of stress for all the interesting failure modes have been obtained, it is possible to observe if their aggregation reaches a prefixed threshold as a permissible limit, or not. In the case that this limit is close to being reached, maintenance actions are suggested to be executed by the maintenance model in order to maintain the levels of stress at a desired point. The paper presents the application of the proposed maintenance model to the case of some types of failure modes of wind turbines.
Keywords: maintenance model, stress indicator, wind turbine, component life monitoring
11th International Probabilistic Safety Assessment and Management Conference & The Annual European Safety and Reliability Conference Scandic Marina Congress Center ( PSAM11 & ESREL 2012 )
Published: June 2012.