Feasibility of magnetic fiber-optic based corrosion sensor

A fiber optic based corrosion sensor utilizing the magnetic interaction force is proposed. The sensor aims to detect corrosion in structures, which are made from ferromagnetic materials (e.g. pipelines made of carbon steel). It consists of a beam that is made from a non-corrosive material with embedded Fiber Bragg Grating (FBG) sensor and a permanent magnet. The beam is placed in a position such that the permanent magnet is within a few millimeters away from the ferromagnetic material to allow for the generation of the magnetostatic attraction force between the sensor and the pipe. The corrosion causes a reduction in material thickness, which increases the distance between the material and the magnet, thus the attraction force will decrease. This change in the force can be related directly to the change in the strain measured by the optical fiber as it causes a shift in the wavelength of the reflected light. We present initial analytical investigation of the feasibility of the proposed concept for practical application of monitoring the external corrosion process on the exposed pipelines. The estimated magnitude of strain change due to corrosion is within the measurement range of typical FBG strain sensors.

[1]  Nicole Jaffrezic-Renault,et al.  Elaboration of an optical fibre corrosion sensor for aircraft applications , 2004 .

[2]  Nader Vahdati,et al.  Strain based FBG sensor for real-time corrosion rate monitoring in pre-stressed structures , 2016 .

[4]  Neil G. Thompson,et al.  CORROSION COST AND PREVENTIVE STRATEGIES IN THE UNITED STATES , 2002 .

[5]  G. Akoun,et al.  3D analytical calculation of the forces exerted between two cuboidal magnets , 1984 .

[6]  Alireza Bahrampour,et al.  Transient response of buried oil pipelines fiber optic leak detector based on the distributed temperature measurement , 2013 .

[7]  David John Hill,et al.  Distributed fibre optic sensors for pipeline protection , 2009 .

[8]  Qian Tian,et al.  Optical and electrochemical measurements for optical fibre corrosion sensing techniques , 2006 .

[9]  Hooman Nabovati,et al.  Fiber Optic Sensors , 2008 .

[10]  Hossam A. Gabbar,et al.  Review of pipeline integrity management practices , 2010 .

[11]  Jinping Ou,et al.  Brillouin Corrosion Expansion Sensors for Steel Reinforced Concrete Structures Using a Fiber Optic Coil Winding Method , 2011, Sensors.

[12]  Junqi Gao,et al.  Monitoring of corrosion in reinforced concrete structure using Bragg grating sensing , 2011 .

[13]  António Barrias,et al.  A Review of Distributed Optical Fiber Sensors for Civil Engineering Applications , 2016, Sensors.

[14]  Clara J. Pacheco,et al.  A Noncontact Force Sensor Based on a Fiber Bragg Grating and Its Application for Corrosion Measurement , 2013, Sensors.

[15]  J. Buerck,et al.  OTDR fiber-optical chemical sensor system for detection and location of hydrocarbon leakage. , 2003, Journal of hazardous materials.

[16]  T. K. Gangopadhyay,et al.  Fibre Bragg gratings in structural health monitoring—Present status and applications , 2008 .

[17]  Meng-Tsan Tsai,et al.  Fiber optic in-line distributed sensor for detection and localization of the pipeline leaks , 2007 .

[18]  Kenneth T. V. Grattan,et al.  Fiber optic sensor technology: an overview , 2000 .