ASTM B594-02 pdf free.Standard Practice for Ultrasonic Inspection of Aluminum-Alloy Wrought Products for Aerospace Applications.
Indications from a single discontinuity equal to orgreater than the response from a 2/%ain.(0.79 mm) flat-bottomhole at the estimated discontinuity depth shall not be more than0.5 in. (12.7 mm) in length.Multiple discontinuities shall not be of such size orfrequency as to reduce the first back reflection to 50 % or lessof the first back reflection from normal material of the samegeometry,with the crystal parallel to the front and backsurfaces to ensure that the loss of back reflection is not causedby surface roughness or part geometry variation.
Indications from a single discontinuity shall notexceed the response from a 5/%ain. (1.98 mm) flat-bottom holeat the estimated discontinuity depth.
Multiple indications in excess of the response from a3/64 in. (1.19 mm) flat-bottom hole at the estimated discontinu-ity depth shall not have their indicated centers closer than 1.0in. (25.4 mm).Indications from a single discontinuity equal to orgreater than the response for a 3/6ain. (1.19 mm) flat-bottomhole at the estimated discontinuity depth shall not be more than1.0 in. (25.4 mm) in length.Multiple discontinuities shall not be of such size orfrequency as to reduce the first back reflection to 50 % or lessof the first back reflection from normal material of the samegeometry,with the crystal parallel to the front and backsurfaces to ensure the loss of back reflection is not caused bysurface roughness or part geometry variation.
Indications from a single discontinuity shall notexceed the response from a 8/%ain. (3.18 mm) flat-bottom holeat the estimated discontinuity depth.
This class of discontinuity limits may apply tonon-critical areas and to some areas specified in zoned engi-neering drawings.
Indications from a single isolated discontinuity shallnot exceed the response from a 8/%ain. (3.18 mm) flat-bottomhole at the estimated discontinuity depth.Evaluated discontinuityindications greater than those included in the four specifiedclasses shall be permitted in the inspected product if it isestablished that they will be removed by machining or that theyare located in non-critical areas not designated as Class C.
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, the couplant,andany correction factors employed for the inspection.
Preparation of a drawing showing the location of allsignificant discontinuities in the inspected product is recom-mended when the ultimate rejection or acceptance of theproduct is to be determined by negotiation between themanufacturer and the purchaser.
The identification of an acceptable product is desirableand is recommended. For this purpose, a suitable stamp shouldbe employed to indicate conformance to this ultrasonic prac-tice. The recommended stamp for identifying acceptable prod-ucts should contain a symbol“U”’ and identification of theinspection facility and the inspector. An example is shown inFig. 3.No information is presented about either the precisionor bias of ultrasonic inspection for presence of discontinuitiessince such inspections are based on comparative classificationsagainst reference blocks.ASTM B594 pdf download.