Departmental Papers (MSE)

Document Type

Journal Article

Date of this Version

November 2007


A general method for predicting the life time of a polyethylene structure that fails by slow crack growth was applied to the case of externally notched pressurized pipes. An analysis of experimental data indicated that the residual stress must be taken into account. The critical notch depths associated with a given life time were calculated as a function of pipe size, PENT value of the resin and temperature. The results were tabulated to serve as practical guide lines for deciding whether a pipe should be discarded if the notch is too deep. The current 10% of the thickness rule now used by industry was found to be invalid.


Postprint version. Published in Polymer Engineering and Science, Volume 47, Issue 11, November 2007, pages 1951-1955.
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Date Posted: 05 March 2008

This document has been peer reviewed.