Failure behaviour of preloaded API line pipe threaded connections

Abstract

This paper reports on numerical and experimental work concerning the fatigue behaviour andsealing capacity of threaded pipe connections (1” API Line Pipe). Numerical simulations are performedusing Abaqus®in combination with ThreadGen©. The fatigue life of a thick-walled standard coupling isdetermined using a four-point bending test. The corresponding S-N curve is compared to results of previouswork on thin-walled specimens. It can be concluded that the standard thick-walled connection has a higherfatigue life than thin-walled ones. In future work, the prediction of fatigue life using established multi-axialcriteria will be evaluated. Further, the sealing capacity of several couplings will be investigated bysubmitting them to different combinations of internal pressure and axial force. Hereto, a specific test setupis designed. The results will then be presented as a test load envelope