Patent ID: 7154264

Claim:
A method for inspection of a pipeline having internal restrictions, comprising the steps of: affixing a collapsible excitation coil comprising a plurality of electrically interconnected collapsible excitation coil segments to a first end of an inspection pig structure, the inspection pig structure including an instrumentation housing; affixing a collapsible sensor array to a second end opposing the first end of the inspection pig structure; passing the inspection pig structure with the affixed collapsible excitation coil and the affixed collapsible sensor array through the pipeline having internal restrictions; collapsing the excitation coil and the sensor array from an expanded deployed position for enabling the inspection pig structure with the affixed collapsible excitation coil and sensor array to traverse a first internal restriction in the pipeline; and returning the affixed collapsible excitation coil and sensor array to an expanded deployed position when the first internal restriction has been traversed.