Coating disbond on buried pipelines contineus to be a major problem world-wide. Disbonds left unrepaired promote both corrosion and stress-corrosion cracking, which are much more costly to repair. Improved inspection technology is currently needed to detect and characterize disbonds. HD Laboratories, Inc. proposes to refine and test a novel method of detecting and assessing coating disbonds and corrosion onset in buried pipelines. This effort is an extension of the work funded at Johns Hopkins University by the Pipeline Research Council International. The technology utilizes Magnetially-assisted Electrochemical Impedance Spectroscopy (MEIS). This technology has the potential to not only identify and size coating disbondments, but to indicate the type of fill medium in the disbond volume, such as water, air, or corrosion product. The proposed Phase I work will address two objectives: 1) Test an advanced method for implementing MEIS which would form the basis of Phase II and III systems, and 2) Quantify the ability of MEIS for characterizing disbonded coating, using the advanced implementation on buried calibration pipes with synthetic disbond.
