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From a practical perspective, the new phased array systems are relatively easy to use and are portable, thus allowing easy access to the inspection location. This is in sharp contrast to older phased array systems that were essentially immobile, quite heavy and thus difficult to deploy. Lastly, from the commercial perspective these systems have now come down in price to a level that they can be used by organisations that span many different fields. This has also led to a corresponding lowering of cost that has allowed their usage in many new commercial applications. It is these three factors acting together that have driven the large increase in phased array usage. Nevertheless, phased array testing remains an ultrasonic testing technique and the fundamentals of physical principles shall be kept in mind by the operators. The application of such a technique needs specific training, verification of the competencies and careful verification of the procedures.

IIW Sub Commission V-C has prepared a “Phased Array Handbook” to be issued soon by DVS media GmBh.

ASME has published separate Code Cases on phased arrays to cover both manual and encoded scanning. These Code Cases specifymany of the parameters and requirements for performing phased array inspections.

ASME VIII Div2 and B31.3 defines the use of ultrasonic testing in lieu of RT inspection and the acceptance criteria to apply. Phased array or Time of Flight Diffraction method (TOFD) can comply.

Figure 5.15 Phased array inspection in lieu of radiographic inspection on welds in piping ( according to ASME B31.3) ( Reproduced courtesy: Institut de Soudure)

Figure 5.16 Examples of Phased array inspection results (Reproduced courtesy: Institut de Soudure)

ISO standardisation now takes into account TOFD and phased array inspection related to the weld quality class defined in ISO 5817 provided the corresponding testing and acceptance levels as defined in ISO 17635 are met.( see Figure 5.17 ).

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