Physico–statistical models based on the residual defectiveness of structural materials - Probabilistic Safety Assessment for Optimum Nuclear Power Plant Life Management (PLiM) - page 121

Macrodefects

a)

b)

￿ ￿ ￿ ￿ ￿

c)

h
cr

a

5.2 Dependence of the number of defects N on the size a :
a) general view, b) pressure vessel with wall thickness s ; c) pressure
vessel after the hydraulic test.

distinguished them from the defectiveness identified in inspection, which
in most cases is characterised by the curve shown in Fig. 5.4.
Obviously, if all the defects in the structure with the size a > a 0 would be
detected with 100% certainty, i.e. all defects with a > a 0 would be detected
and repaired, then the curves of the detected and residual defectiveness
would correspond to curves 2 and 3 in Fig. 5.5. Moreover, the number of
defects with the size a > a 0 after inspection and repair would be equal to 0.