Ricerca CERCA

Magnet-assisted Fiber Optic Sensing for Internal and External Corrosion-induced Mass Losses of Metal Pipelines under Operation Conditions

estero Tesi all'estero


Descrizione The U.S. hazardous liquid and natural gas transmission pipelines have reached approximately 2.5 million miles. Corrosion has caused a loss of over $12 billions per year. The current practice of internal corrosion monitoring is mainly associated with the use of pigging inside a pipeline, resulting in operation downtime and significant revenue loss. If not piggable, a pipeline may be monitored for wall thinning using an ultrasonic transducer that is installed when the pipeline coating is removed, potentially triggering additional corrosion. The overarching goal of this study is to transform the current internal corrosion monitoring technologies to a fiber optic sensing system to ensure pipeline safety at critical sections, and externally monitor internal pipeline corrosion to ensure normal operation of coated pipelines. The sensing system includes several sensor nodes and an interrogator for multiple FBG/EFPI and multiplexed LPFG sensors. Each node mainly consists of a cylinder magnet attached to the external surface of a coated steel pipe through a plexiglass tube, a hybrid FBG/EFPI sensor, and a LPFG sensor coated with Fe-C mixture that represents the main constituents of a low-carbon steel pipe to be monitored. The magnetic force between the magnet and the steel pipe is a function of wall thickness and, when applied on the external coating in between, is monitored by the FBG/EFPI sensor through the measurement of micrometer displacement in the coating. The magnetic field is simulated numerically with the use of a multiphysics software. The relation between the magnetic force and the induced displacement on the pipeline coating is derived analytically and validated experimentally, taking into account creep and temperature effects over time. The steel thickness reduction due to external corrosion is accurately measured so that the thickness reduction due to internal pipeline corrosion can be evaluated under operation conditions. The sensors are individually characterized in laboratory with electrochemical tests. They are integrated and demonstrated for field performance under operation conditions of a pipeline through a close collaboration with a North America pipeline company.

Conoscenze richieste English speaking

Note Missouri University of Science and Technology

Scadenza validita proposta 26/04/2020      PROPONI LA TUA CANDIDATURA

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