Loading patent…
AssigneeWestinghouse Electric Corp.
InventorsGeorge E. Rudd, Rajender K. Sadhir, William G. Clark, Jr., Robert E. Shannon
Estimating the term…
A nondestructive method for determining the thickness of a non-electrically conductive material is provided that comprises the steps of uniformly dispersing a quantity of a ferromagnetic particulate tagging substance in the material whose presence and distribution is detectable by a form of radiant energy, such as the high-frequency electromagnetic field emanated from an eddy current probe, and then calibrating the output of the eddy current probe with a sample material having a known thickness that has been tagged with the same tagging substance at the same density. The thickness of the material is then determined by comparing the amplitude of electromagnetic coupling with the material with that obtained with the sample. The method may advantageously be applied to determine the thickness of a granular material such as asphalt concrete over a roadbed, as well as the strain and wear patterns in gaskets formed from elastic materials.
A method for determining a thickness of a structure formed of non-electrically conductive material that is adjacent to a second material that is both non-electrically conductive and nonferromagnetic by means of an eddy current probe that electromagnetically couples with ferromagnetic material, said coupling being characterized by a magnitude, comprising the steps of:
A method for determining a thickness of a structure of a non-electrically conductive material that is adjacent to another structure that is both non-electrically conductive and non-ferromagnetic by means of a probe assembly that emanates electromagnetic radiation at a plurality of different frequencies that electromagnetically couple with ferromagnetic material, said coupling being characterized by a magnitude, comprising the steps of
Dependencies are inferred from the claim text.