Single block method

[NikolaiV]

Здравствуйте.
Фраза из методики (ASTM) ультразвукового контроля поковок. В параграфе описываются методы калибровки прямых преобразователей (нужный термин - в п. 9.12.1):

9. Straight-Beam Examination
9.1 Method of Calibration:
9.1.1 Perform calibration for straight-beam examination on the flat-bottom hole size determined by the applicable quality level (see Section 12).
9.1.2 Determine the calibration method by the test metal distance involved.
9.1.2.1 Thicknesses up to 6 in. [150 mm] may be examined using either the single-block or the distance-amplitude curve calibration method.

(a) Single-Block Method — Establish the test sensitivity on the reference standard representing the forging thickness. Drill flat-bottom holes normal to the examining surface, to midsection in materia! up to 1.5 in. [40 mm] in thickness and at least 0.75 in. [20 mm] in depth but no deeper than midsection in thicknesses from 1.5 to 6 in. [40 to 150 mm]. Make evaluations of indications at the estimated discontinuity depth at which they are observed using supplementary reference standards, if necessary.

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