Defect Sizing from UT Indications Calculator

Size defects from UT indications using 6dB drop and DGS (Distance-Gain-Size) methods per EN 1712 and ASME V

Input Parameters

Results

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Estimated Defect Size
mm
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Equivalent Reflector Size
mm
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Beam Width at Depth
mm
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Sizing Confidence
Note: The 6dB drop method works best when the defect is larger than the beam width. For smaller defects, DGS/AVG or amplitude comparison methods are more accurate. Per EN 1712 and ASME V Article 4.

Reference

6dB Drop: defect_size = drop_width - beam_correction DGS (AVG): ERS from amplitude vs. distance-gain curves Near field: N = D^2 / (4 x lambda) Beam divergence: sin(theta) = 1.22 x lambda / D Equivalent reflector: 20 x log10(d/d_ref) = dB_difference