ASTM A939-96(2001) pdf free download.Standard Test Method for Ultrasonic Examination from Bored Surfaces of Cylindrical Forgings.
ASTM A939-96(2001) covers a basic procedure of ultrasonically inspecting cylindrical forgings with bores from the bore surface.
ASTM A939-96(2001) applies to the manual testing mode. It does not restrict the use of other testing modes, such as mechanized or automated.
ASTM A939-96(2001) applies to cylindrical forgings having bore sizes equal to or greater than 2.5 in. (63.5 mm).
6. Procedure
6.1 Establish the inspection sensitivity such that the reflec tion amplitude equals 100 %o of the screen height throughout the entire inspection, using the calibration hole, specified by the purchaser drilled parallel to the bore surface.
6.2 Check the distance calibration for linearity.
6.3 Using only one transducer connected with pulse delay. mark the location of the reflected signal from the curved surface of the plexiglass shoe as the bore suiface.
6.4 Record the distance from the bore suface to the side of the calibrations hole.
7. Report
7. 1 Report the following information:
7. 1. 1 Amplitudes of all indications as a percentage of the calibration hole sensitivity.
7.1.2 Axial locations of all indications,
7. 1.3 Radial and circumferential locations of all indications.
7. 1.4 Areas with high densities of indications as levels of 5 % increments. and
7.1.5 All reflection losses of 20% or more.