【国外标准】 Standard Practice for Ultrasonic Examination of Austenitic Steel Forgings

This test method deals with the procedures for the standard practice of performing contact, pulse-echo ultrasonic examination of austenitic steel forgings by the straight and angle beam techniques. This practice does not cover the ultrasonic examination of nonmagnetic retaining ring forgings. The instrument used for this test method shall be the electronic pulsed reflection type. Prior to examination, specimens shall be heat treated and machined to a rectangular, parallel, or concentric surface configuration, and its surface shall be free of extraneous material such as loose scale, paint, and dirt. Calibration of the apparatus shall be done by either the single-block method or distance-amplitude curve method. Choice of method to be employed shall be determined by the test metal distance involved. Quality levels for acceptance, established by the type and amount of indication present, are detailed thoroughly.1.1 This practice2 covers straight and angle beam contact, pulse-echo ultrasonic examination of austenitic steel forgings produced in accordance with Practice A388/A388M and Specifications A965/A965M and A1049/A1049M.1.2 Ultrasonic examination of nonmagnetic retaining ring forgings should be made to Practice A531/A531M rather than this practice.1.3 Supplementary requirements of an optional nature are provided for use at the option of the purchaser. The supplementary requirements shall apply only when specified individually by the purchaser in the purchase order or contract.1.4 This practice is expressed in inch-pound and SI units; however, unless the purchase order or contract specifies the applicable “M” specification designation (SI units), the inch-pound units shall apply. The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the practice, the SI units are shown in brackets. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.