In a previous publication, the use of a simple two dimensional finite difference model to predict hydrogen distribution in a simulated part wall pipeling girth weld repair was demonstrated. The validity of the model prediction was assessed usign slow bend tests where the deflection to failure was an indirect indicator of the local bulk hydrogen concentration at the critical site for delayed cracking. In the present investigation, the same hydrogen diffusion model has been used to predict the maximum time for delayed cracking in a simulated girth weld repair for two ambient temperatures, (20 deg C and -10 deg C). These predictions are compared with the delayed cracking times in "constant deflection" tests performed at the selected ambient temperatures.
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