Mechanical Fracture Predictions for Sensitized Stainless Steel Piping with Circumferential Cracks.

摘要

Circumferential intergranular stress corrosion cracks have been discovered in the heat-affected zones of girth welds in the Type 304stainless steel recirculation bypass piping systems of several boiling water reactor (BWR) plants. To determine the residual strength of the cracked pipe,an integrated program of small-scale laboratory experiments full-scale pipe tests,finite-element computation,and a mechanical failure analysis was conducted. After investigating several candidates,the work has shown that a simple plastic collapse criterion can most effectively be used to predict failure in Type 304stainless steel pipes with circumferential cracks. Recommendations for extending the work to permit more accurate and more widely applicable predictions of the margin of safety for arbitrarily shaped cracks in pipes are also given in the report.