Definition(s)
Circular Magnetic Field or Circumferential Magnetic Field
Magnetic field in or surrounding a current-carrying conductor, or OCTG, such that the magnetic field is oriented circumferentially within the wall of the OCTG.
Source: API RP 5A5, Field Inspection of New Casing, Tubing, and Plain-end Drill Pipe, Reaffirmed August 2010. Global Standards