Prediction of the failure pressure for complex corrosion defects

Abstract

A new method for predicting the failure pressure of corrosion defects in pipelines has been developed. The failure pressure of a plain pipe represents an upper limit for the failure pressure of a pipe with a corrosion defect. The failure pressure of a uniform depth, infinitely long groove, where the depth is equal to the maximum depth of the corrosion defect, represents a lower limit for the failure pressure of a pipe with a natural corrosion defect. The predicted failure pressure can be calculated from these limits using the weighted depth difference (WDD) method, which accounts for the defect geometry and any interaction with adjacent defects. The WDD method has been validated using the results of 40 burst tests of pipe sections containing real corrosion defects. The results indicate that this method provides more accurate burst pressure predictions than the currently accepted corrosion defect assessment procedures.