Abstract
In order to rationalize the safety margin of the pressure equipments which have local metal loss, we apply the probabilistic reliability method to the assessment. The modeling of the local metal loss is based on API 579-1⁄ASME FFS-1 and we consider the safety margin of its assessment criterion. Moreover, we proposed the assessment curve based on the reliability. As a result of calculation, we showed that the reliability index of the assessment criterion of API 579-1⁄ASME FFS-1 depends on the dimension of local metal loss. Therefore, the assessment criterion of API 579-1⁄ASME FFS-1 can be rationalized from the reliability point of view. The proposed assessment curve based on the reliability can assess the local metal loss based on quantified safety margin and can expand the accepted area for the local metal loss compared with that by API 579-1⁄ASME FFS-1.
