FORGING.docVIP

ASME SEC.V ARTICLE: - 23 SA-388 SPECIFICATION FOR ULTRASONIC EXAMINATION OF HEAVY STEEL FORGINGS SA-745 SPECIFICATION FOR ULTRASONIC EXAMINATION OF AUSTENITIC STEEL FORGINGS SCOPE: - SCOPE: - This practice covers the examination procedure for the contact, pulse echo ultrasonic examination of heavy steel forgings by straight beam and angle beam techniques. The straight beam techniques include utilization of the DGS (Distance Gain Size) method This practice covers the examination procedure for the contact, pulse echo ultrasonic examination of austenitic steel forgings by straight beam and angle beam techniques or both SEARCH UNIT: - SEARCH UNIT The ultrasonic instrument shall have a minimum capability for examining at Frequencies from 1 to 5 MHz. Search units having a transducer with a maximum active area of 1 in2 (650mm2) with ? in. (20mm) minimum to 11/8 in. (30 mm) maximum dimensions shall be used For straight-beam scanning and search unit equipped from 1/2 by 1 in. (13 to 25mm) to 1 by 1 in. (25 by 25 mm) shall be used for angle beam scanning. Others search units may be used for evaluating and pinpointing Indication. The system shall have a minimum capability for operating at frequencies 0.5 to 5 MHz. Either video or R-F presentation is acceptable. The maximum nominal active area of 11/2 in2 (970mm2) with 13mm minimum to 30 mm maximum dimension or 20mm minimum dimension shall be used for straight beam examination. Angle beam scanning transducer shall have a nominal active area of ? “ to 1” in2. The nominal test frequency shall be 2.25 MHz Use of this frequency will generally be restricted due to attenuation. 1 MHz is acceptable and will be the frequency generally applicable. When necessary, due to attenuation 0.5 MHz examination frequency may be used. In the event that adequate penetration of certain regions is not poss