Patent ID: 9733216
Date: 2017-08-15
CPC Classifications: G01N

Claim:
1. A pipeline inspection gauge for monitoring the structural integrity of a pipeline, the pipeline inspection gauge being adapted to be inserted in a pipeline and to move along the pipeline, wherein the pipeline inspection gauge is adapted, during a monitoring operation, to generate a magnetic field which is conveyed to the wall of the pipeline and to reveal variations in the magnetic field using a sensor system, the pipeline inspection gauge comprising: a central electromagnetic device adapted to generate a magnetic field; a first magnetic conveyor connected to said central electromagnetic device suitable for conveying the magnetic field generated by the central electromagnetic device to the wall of the pipeline; a second magnetic conveyor connected to said central electromagnetic device suitable for facilitating the closing of a magnetic circuit, conveying the magnetic field from the wall of the pipeline towards the central electromagnetic device; at least one sensor system for revealing the magnetic field; electric means for powering the pipeline inspection gauge and acquiring and storing data relating to the magnetic field detected; wherein said central electromagnetic device includes a plurality of divided elements made of a ferromagnetic material that are each a smaller size than said central electromagnetic device, wherein said divided elements are held together by a polymeric material adapted to degrade following prolonged contact with a mixture of hydrocarbons which results in separation of said divided elements and loss of the generated magnetic field; and a solenoid that envelops said divided elements which, when subjected to an electric current, generates the magnetic field which passes through said divided elements longitudinally.