Temperature Correction Formula

[nde3rich]

Can anyone tell me the formula used to manually correct ultrasonic thickness measurements for elevated temperatures ?

 

[JR97]

nde3rich,

According to Krautkramer - Ultrasonic Testing of Materials pg 14, the longitudinal velocity (which is applicable to thickness gages) decreases with a temperature increase by about 1 m/s per degree C on average up to 1200 C. Using the nominal longitudinal velocity for steel of 5,900 m/s; the thickness reading would be in error (thicker than actual) by .0169% for each degree C the test piece is above the calibration standard.

JR97

 

[nde3rich]

thanks, but I was looking for the expanded version.

 

[JoeTank]

ASME SE797 states a rule-of-thumb... for every 100F increase in temperatrure, the plate thickness measures approximately 1% thicker.

Joe Tank

 

[unclesyd]

All the above is essentially correct unless the temperature of your transducer is changing. There has to some means keep the transducer temperature near the calibration temperature.