Partial Safety Factor (PSF) Approach in Japanese FFS Code, HPIS Z101 Level 2

Abstract

One of the features of HPIS Z101 Level2 method, which is to be published as a Japanese Fitness-For-Service (FFS) code for pressure equipment, is to use plural FADs (Fracture Assessment Diagrams) dependent on the materials. Regarding the FFS assessment methods for a crack-like flaw, Partial Safety Factor (PSF) is becoming a major approach in considering the effect of the variance of parameters for the assessment, such as applied load, material properties and detected dimensions of the flaws concerned. To apply this approach to the HPIS code, different PFSs for FADs dependent on materials should be prepared. PSFs with various conditions are calculated for the HPIS code, by the AFOSM (Advanced First-Order Second Moment) method. Comparison with PSFs in other preceding FFS codes, such as API 579-2000 and BS 7910-2005, is being conducted.