Study on Performance Degeneration Model for Remaining Lifetime of Corroded Pipeline

During operating chronically, because of corrosion of medium and soil, micro-plasticity deformation of pipe material, changing of structure and filtering of hydrogen, there are not only various cumulative damages, but also ageing and hydrating phenomenon in pipeline which maybe make pipe material brittle-ness and its mechanical performance attenuated. In this paper, the remaining lifetime of corroded pipeline is studied from material performance degeneration and cumulative damage. For this reason, the notions of shear damage rate and yield capability ratio are defined, and their characteristics on time are studied. A method of determining operation lifetime of pipeline is put forward on limited carrying capacity of structure and plasticity deformation. The models for calculating remaining lifetime are developed by defining of shear damage rate and yield capability ratio. Finally, an example is given.