Bursting of line pipe with long external corrosion

Abstract Application of AGA NG-18 or CSA-A245.1 recommendations for the evaluation of external corrosion on line pipe appear more conservative for long defects and long spiral defects than for shorter defects. To investigate the burst behaviour of pipe with long defects, a finite element model was developed and the predictions compared with burst tests. The model was used to investigate the effect of the geometry and spiral angle of single long corrosion grooves. Assuming a power hardening material, equations are proposed to predict the reduction in burst pressure of line pipe with long external corrosion defects.