DAC Curves for Defect Sizing

DAC curves (Distance Amplitude Correction) are an essential tool for sizing defects detected by ultrasound. The DAC curve, built experimentally on a reference block, compensates for signal attenuation with depth: this makes it possible to compare echo amplitudes correctly at different distances and to assess the severity of the defect.

In this section we bring together articles and working procedures on the use of DAC curves in Dakota flaw detectors, in particular for weld inspection to AWS D1.1 and other codes.
Dakota instruments with DAC curves

Dakota FX70-DL — portable flaw detector supporting DAC and DGS-AVG curves.
Dakota FX81-DL — benchtop version for procedure qualification.

Further reading
AWS D1.1 ultrasonic weld inspection: requirements · AWS D1.1 weld inspection with the Dakota FX70-DL · FX70-DL vs FX81-DL compared

To qualify a UT procedure with DAC curves on Dakota flaw detectors, contact the RODER team.