Magnetic flux leakage inspection tool for pipelines

A pipeline feature or defect location system comprising:

• an in-line-inspection system;
• globally positioned above ground control points placed at intervals along the pipeline,
• said control points having geographic coordinates from a global positioning satellite;
• an inertial navigation system;
• a computer including post-processing software.

A method for inspecting the integrity of a pipeline comprising:

• establishing control points along the pipeline;
• inspecting a length of the pipeline using a pipeline pig, wherein the pig includes an in-line inspection tool and an inertial navigation system;
• identifying, features or defects along the pipeline by use of the in-line inspection tool;
• collecting data regarding the features or defects;
• determining the position and attitude of the pig along its trajectory within the pipeline using the inertial navigation system;
• collecting data in the form of geographic coordinates regarding the position and attitude of the pig along its trajectory;
• determining the geographic coordinates of the control points with the inertial navigation system;
• determining the global position satellite coordinates of the control points;
• adjusting the geographic coordinates of the control points calculated with the inertial navigation system to the accuracy of those calculated with the global positioning system;
• correcting the data collected regarding the position and attitude of the pig determined along its trajectory within the pipeline using the inertial navigation system based on the global position satellite coordinates of the control;
• determining geographic coordinates for the features or defects located along the pipeline using the corrected position and attitude of the pig.

A method for locating features or defects in a pipeline, comprising:

• setting control points at intervals along the pipeline;
• performing in-line inspection of the pipeline using an in-line inspection tool:
• wherein said in-line inspection tool includes an inertial navigational system;
• recording data from the in-line inspection tool and the inertial navigational system;
• determining the position of control points along the pipeline by use of a global positioning system;
• recording data from the global positioning system;
• and
• tying the data from the in-line inspection system, the data from the inertial navigational system and the data from the global positioning system to determine the location of the features or defects in the pipeline.