Dynamics of Extended Pipeline Failure

The results of full-scale tests of pipes 1420 mm in diameter at the testing ground of OOO Gazprom Transgaz Yekaterinburg are analyzed. 42 stalks of pipes of strength class K65 (X80) from eight manufacturers are subjected to extended failure tests (longitudinal rupture up to 100 m). The dynamic gas pressure at the edge of a traveling crack is lower than the initial pressure by 3–7 times. At a long path, the velocity of a propagating crack is 1.5–2 times lower than the starting velocity. A critical extended failure condition is the transition of a crack from the source of damage to a stationary path (at the first path meters). The further crack propagation to stop is a random characteristic. In all tests, a crack passes through pipes with an impact toughness KCV–40 300 J/cm2.