Eddy-current examination is a nondestructive method of locating surface discontinuities in a product. Signals can be produced by discontinuities located on the surface of the rod. Since the density of eddy-currents decreases nearly exponentially as the distance from the surface increases, deep-seated defects may be undetected.

Some indications obtained by this practice may not be relevant to product quality. For example, a signal may be caused by minute flaws or irregularities, by anomalies in the material, or by other factors such as operator error, or a combination thereof, that are not detrimental to the end use of the product. Nonrelevant indications can mask unacceptable discontinuities. On the other hand, relevant indications are those that may result from nonacceptable discontinuities and should be determined by agreement between the user and the supplier. Any indication that is believed to be irrelevant shall be regarded as unacceptable until it is demonstrated by reexamination or other means to be nonrelevant.

1.1 This practice covers the procedures that shall be followed in electromagnetic (eddy-current) examination of copper redraw rods for detecting discontinuities or imperfections of a severity likely to cause failure or markedly impair surface quality of the rod. These procedures are applicable for continuous lengths of redraw rod in diameters from ¼ to 1³/₈ in. (6.4 to 35 mm) suitable for further fabrication into electrical conductors.

1.2 This practice covers redraw rod made from tough-pitch or oxygen-free coppers.

1.3 The procedures described in this practice are based on methods for making use of stationary encircling annular test coil systems.

1.4 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.