Nondestructive Testing (NDT) is a form of engineering evaluation that detects and interprets flaws in materials, while causing no harm to the materials or structure under examination.  It is an exacting science, with highly developed testing techniques.  NPI is a dedicated, full-service NDT Company.  One of our methods is the Eddy Current Method.  This method uses circulating electrical currents induced in an electrically conductive test object by an alternating magnetic field.  The current flow in the test specimen creates its own magnetic field.  Interruptions or changes in current flow result in changes in this magnetic field, which are detected, displayed and interpreted.