Fatigue Crack Growth and Penetration Behavior of a Pipe Subjected to Bending Load. 1st Report. Pipe with a Surface Crack on the Outside.

Abstract

A fatigue test has been carried out at room temperature in air on a carbon steel pipe which has a crack on its outer surface. Special attention was paid to crack growth rate, crack shape and fatigue life. A new equation was proposed for evaluating K after crack penetration. The main results obtained in this study are as follows. (1) Before crack penetration, crack growth behaviors such as aspect ratio and leak life were evaluated using Newman-Raju's equation and plate model. (2) After crack penetration, crack growth behaviors such as crack shape and fatigue life were evaluated using the equation proposed in this paper.