UNDERSTANDING THE IMPACT OF HIGH-MAGNITUDE REPAIR-WELD RESIDUAL STRESSES ON DUCTILE CRACK INITIATION AND GROWTH - THE STYLE MOCK - UP 2 LARGE SCALE TEST

摘要

The STYLE EU Framework 7 project is examining the structural integrity of non-RPV components in reactor primary circuits. One of its focus areas is the impact of high magnitude weld residual stresses on the initiation and growth of cracks in austenitic stainless steels. A large scale fracture test has been performed on Mock-up 2, a butt-welded austenitic steel pipe containing a short, deep weld repair that induces weld residual stresses of yield magnitude over the length of repair. A through-thickness crack was introduced into the repair weld, and its behaviour under superimposed global bending load was investigated in a large scale fracture test. This paper describes the process of test design, the pre-test predictions made using the R6 defect assessment procedure, and the outcome of the test.