BULLETIN 432-1998 FATIGUE STRENGTH REDUCTION AND STRESS CONCENTRATION FACTORS FOR WELDS IN PRESSURE VESSELS AND PIPING: )INTERPRETIVE REVIEW OF WELD FATIGUE-STRENGTH-REDUCTION AND STRESS-CONCENTRATION FACTORS ; II)FATI
1. Interpretive Review of Weld Fatigue-Strength-Reduction and Stress-Concentration Factors: The objectives of this report are to (1) clarify the current procedures for determining values of fatigue-strength-reduction factors (FSRFs)@ (2) collect relevant published data on weld-joint FSRFs@ (3) interpret existing data on weld-joint FSRFs@ (4) facilitate the development of a future database of FSRFs for weld joints@ and (5) facilitate the development of a standard procedure for determining the values of FSRFs for weld joints. The main focus of this report is on weld joints in Class 1 nuclear pressure vessels and piping. However@ relevant fatigue data on similar weld joints for other applications@ such as bridges and offshore structures@ also are reviewed and interpreted. 2. Fatigue-Strength-Reduction Factors Based on NDE: This report addresses applying fatigue-strength-reduction factor (FSRE) to a weld surface@ based on the nondestructive examination (NDE) that is performed. The development is focused on Class 1@ pressure vessels of the ASME Boiler and Pressure Vessel Code@ Section III@ NB and NC-3200 and Section VIII Division 2 (ASME Code@ 1997). It is the position of this report that the fatigue life is a function of the quality of the material and the NDE gives an assessment of this quality. This leads to the conclusion that weld metal will have a fatigue life consistent with the prediction of the ASME Code S-N curves and equivalent to that of base metal provided a full NDE is applied. With reduced NDE@ the application of an FSRF in the analysis maintains consistency. The report develops and defines the basis for each FSRF. For example@ it explains why one NDE technique has a greater impact on fatigue life than another technique@ i.e.@ its omission requires a higher FSRF. Publication of this document - WRC Bulletin No. 432 was sponsored by the Pressure Vessel Research Council of the Welding Research Council.
BULLETIN 432-1998 history
1998BULLETIN 432-1998 FATIGUE STRENGTH REDUCTION AND STRESS CONCENTRATION FACTORS FOR WELDS IN PRESSURE VESSELS AND PIPING: )INTERPRETIVE REVIEW OF WELD FATIGUE-STRENGTH-REDUCTION AND STRESS-CONCENTRATION FACTORS ; II)FATI