AS 2574-1982

Includes requirements for preparation of test surfaces and for establishing scanning sensitivity and describes two procedures for determining attenuation and for sizing of discontinuities located. Quality levels are classified in terms of four zones of influence within a casting. Appendices cover purchasing guidelines, factors affecting probe selection, methods for determination of attenuation and transfer losses, guidance on the nature of discontinuities, their location and identification, procedures for sizing using the 20 dB intensity drop method, use of reflectivity diagrams and compensation for curvature.

This standard sets out methods for the ultrasonic testing of specified areas of heat-treated ferritic steel castings of thickness ranging from 25 mm to 500 mm using A-scan presentation, and for the classification of quality.NOTES:1. Although the methods outlined in the standard are intended to be applied to heat-treated castings, they may be used on non heat-treated castings, by agreement, provided that it is recognized that because of unrefined grain structures some discontinuities may not be detected and the acceptance standard cannot be applied.2. The standard does not apply to the testing of austenitic steel castings, unless by agreement, because such castings have a columnar structure which is not amenable to grain refining by heat treatment and special considerations are needed.3. Supplementary information required to establish appropriate test methods is set out in Appendix A.4. For convenience in the assessment of the integrity of castings manufactured to comply with the requirements of AS 2074, the casting wall thickness is divided into four zones of influence and four quality level classifications (see Section 7).5. Acceptance criteria and/or quality classification for dis-continuities are normally specified in relevant product standards or determined by agreement between the contracting parties after due consideration of the size, configuration, and the service requirements of the casting (see Appendix A).6. Any repair welding carried out is deemed to be part of the casting.7. This standard does not include methods for the ultrasonic immersion testing of castings.

Under Revision see DR 98197