Numerical simulation of the severity of surface defects in HDPE Pipes

In this paper an analysis of the evolution of a semi-elliptical crack located at different positions of the wall of an HDPE pipeline under internal pressure is made. The three-dimensional finite element method is used to calculate the integral J. The J integral is important in the extreme positions on the contour of integration. When the ratio (a / t) reaches a critical value (a / t = 0.6), the effect of crack depth becomes important. It’s also shown that for low values of the opening angle of the curve, the crack tends to be propagated from the position 1. The transverse cracks have a lower risk that the axial cracks and then the cracks into interior of the wall of the pipe are more dangerous than the cracks external.