MAGNETIC FLUX LEAKAGE (MFL) technology has been used for a number of decades as a primary technology for inline inspection (ILI). Ongoing ILI developments have produced additional magnetic field technologies that have the potential to greatly augment the capabilities of ILI tools to identify and categorize threats to pipeline integrity. In particular, the residual field and low field technologies utilize second and third quadrant magnetic responses to identify metallurgical anomalies that can accompany mechanical damage or result from manufacturing imperfections. When low field technologies are combined with the traditional MFL and deformation (DEF) technologies in a concurrent data acquisition, a greater potential for identifying interactive threats and an improvement on the traditional ILI capabilities for identifying and characterizing pipeline features emerge. The combined data sets from these technologies highlight the unique contributions of low field data in identifying dent re-rounding, dents with metal loss, and differentiating cold working from corrosion metal loss. This paper presents an additional benefit of the low field data as part of a method for creating a pipe signature and magnetic fingerprint for individual pipe joints which can be used to facilitate a discrepancy analysis of pipeline component records. Low field technology offers what is perhaps the most effective dataset for identifying unique metallurgical anomalies that can indicate the history of a single segment of pipe. The demonstrated successes of low field technology confirm that the inclusion of additional magnetic field technologies within a single tool continues to provide significant advances in the quality and quantity of information that can be gathered with inline inspection tools.
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