Patent ID: 9200508
Filing Date: 2015-12-01
Classification: E21B

Abstract:
1. An apparatus for monitoring a downhole component, the apparatus comprising: an optical fiber sensor having a length thereof in an operable relationship with the downhole component and configured to deform in response to deformation of the downhole component, the optical fiber sensor including a plurality of scattering locations disposed along a length of the optical fiber sensor; an interrogation assembly configured as a swept-wavelength interferometry assembly, the interrogation assembly configured to transmit a non-pulsed, continuous swept-wavelength electromagnetic interrogation signal into the optical fiber sensor and receive reflected signals from each of the plurality of intrinsic scattering locations; a processing unit configured to monitor the downhole component during a downhole operation, receive the reflected signals, select a measurement location along the optical fiber sensor, select a first reflected signal associated with a first intrinsic scattering location in the optical fiber sensor, the first intrinsic scattering location corresponding with the measurement location, select a second reflected signal associated with a second intrinsic scattering location in the optical fiber sensor, perform a Fourier transform on the first reflected signal and the second reflected signal, estimate a phase difference between the first signal and the second signal based on the transformed signals, estimate a parameter of the downhole component at the measurement location based on the phase difference, identify a change in the parameter, and diagnose a potential problem associated with the downhole component based on the change in the parameter.