Fracture & Resistance # 1992 Eindhoven
The basis for the evaluation of polyethylene materials for pressure pipe applications is hydrostatic stress rupture testing for the prediction of long term hoop strength.
However it is crucially important that the fracture properties of the materials are understood and indeed may result in limitations of their use. Slow crack growth has been recognised in pipelines resulting from flaws, notches created during installation, rock impingement and bending loads. This paper outlines the development of the ‘Notched Pipe Test’ for the assessment of the resistance to slow crack growth of PE pipe, carried out by an Ad Hoc Group of ISO/TC 138/SC4 (Plastics Pipes - Gas Applications).