AS ISO 15549:2020 Non-destructive testing一Eddy current testing – General principles.
12.1 Steps in the examination
The detailed steps of the examination shall be defined in the examination procedure (see 13.2).
12.2 Examination coverage
The surface of the product shall be scanned in accordance with the requirements of the application document (see 13.2) or following a written procedure agreed at the time of enquiry and order.
The following should preferably be included:
— the area to be scanned or, alternatively, the area which cannot be scanned;
— the direction of scanning;
— the type of probe and the probe size;
— the speed of the probe relative to the surface;
— the width of coverage of the probe.
The degree of coverage of the surface is determined by the width of coverage of the probe and can also be influenced by the data acquisition rate of the instrument and the speed of the probe relative to the surface.
For complete coverage of the surface without any missed area, two consecutive scanning lines shall not be distant by more than the probe coverage.
12.3 Signal characterization
In order to be able to make a decision, examination results shall be correlated with features of the tested product such as cracks, wear and physical properties.
Application documents or a procedure, agreed at the time of enquiry and order, shall therefore include:
— the type of scanning: manual or mechanized;
— recording requirements;
— evaluation requirements;
— reporting requirements.
Signals are analysed with respect to characteristics, such as the amplitude, the phase or the combination of both in defined ranges.
Classification of indications can then range from a simple mechanized sorting device to a classification using a multiparameter correlation technique based on more than one calibration curve.
12.4 Acceptance criteria
The acceptance criteria and the subsequent action for the product shall be defined in the application documents (see 13.2) or in a written procedure agreed at the time of enquiry and order.AS ISO 15549 pdf download.