ASTM B548-03 pdf free.Standard Test Method for Ultrasonic Inspection of Aluminum-Alloy Plate for Pressure Vessels.
Continue to mark the location of the search unit ateach point where either or both of the discontinuity conditionsspecified in paragraph 8.8.2 are observed. The entire discontinuity shall be outlined even if it extends beyond the original6-in. ( 152-mm) square evaluation scan area.
The estimated discontinuity size is the area defined bythe boundary consisting of successive marks as established bythis procedure.
When the estimated size of a detected discontinuity isdetermined,return the search unit to the original stoppingposition and continue the initial scan to complete the inspection.Upon completing the inspection procedure, measure thelongest dimension of each marked area representing a detecteddiscontinuity.Also, when an engineering drawing showing thepart to be fabricated from the plate is supplied, compare thelocations of the discontinuities with the dimensions on thedrawing.If the longest dimension of the marked area representinga discontinuity causing a complete loss of back reflection(95 % or greater) exceeds 1.0 in. (25 mm), the discontinuity isconsidered to be significant and the plate shall be subject torejection.
If the length of the marked area representing a discon-tinuity causing an isolated ultrasonic indication without acomplete loss of back reflection (95 % or greater) exceeds 3.0in. (76 mm), the discontinuity is considered to be significantand the plate shall be subject to rejection.A plate containing significant discontinuities of rejectable size shall be acceptable if it is established by the purchaserthat the discontinuities will be removed from the plate bymachining during the subsequent fabrication process.Upon specific consent of the purchaser，a plate withsignificant discontinuities may be accepted if repaired bywelding.When required by the purchaser，a report shall beprepared and shall include the date of test and a list ofparameters including the type (model number) of instrumentand search unit, the test method, frequency, and the couplantemployed for the inspection.
Preparation of a drawing showing the location of allsignificant discontinuities in the inspected plate is recommended when the ultimate rejection or acceptance of the plateis to be determined by negotiation between the manufacturerand the purchaser.The identification of an acceptable plate is desirableand is recommended.For this purpose, a suitable stamp shouldbe employed to indicate conformance to this ultrasonic standard.The recommended stamp for identifying acceptable plateis shown in Fig. 1.ASTM B548 pdf download.