A Study on Application-Oriented MFL Magnetizer Design for Safer Inspection of Coastal and Offshore Petroleum Facilities

Abstract Magnetic flux leakage (MFL) testing is a well-established method for detecting metal loss in ferromagnetic structures, including pipelines, storage tanks, and offshore facilities. The detection performance depends not only on the sensing probe but also on the coupled behavior of permanent magnets (PMs), magnetic bridge, air gap, and specimen properties, as well as the operating point on the material’s B–H curve. This study introduces a design framework that systematically links inspecti