Monitoring of conduits

摘要

This application relates to methods and apparatus for monitoring of conduits, especially oil or gas pipelines, as an object such as pipeline pig moves within the conduit. The method comprises monitoring at least part of a conduit (206) using a fibre optic (202) distributed acoustic sensor (204) as the object (208) passes along the conduit. The acoustic signals detected from at least one sensing location (203) as the object moves along the conduit are analysed so as to discriminate acoustic signals received at said sensing location from different locations. The method allows the contributions to the acoustic signal at a given sensing portion from different locations to be separately identified, and can allow the detection of the location of acoustic sources along the conduit even if the source is outside the section of conduit which is monitored. The method provides a method of leak detection that can extend the monitoring of the pipeline beyond the location of the optical fibre.

主权项

1. A method of conduit monitoring comprising:
taking data acquired from at least part of a conduit using a fibre optic distributed acoustic sensor as an object passed along the conduit, said data corresponding to acoustic signals detected at each of a plurality of sensing locations of the fibre optic distributed acoustic sensor; and analysing the acoustic signals detected at at least one sensing location as the object moves along the conduit to determine whether the presence of the object attenuates an acoustic signal so as to discriminate acoustic signals received at said sensing location from different locations.