WRC 492
Piping System SIFs and Flexibility Analysis Criteria: Part 1 & Part 2
Bulletin / Circular by Welding Research Council, Inc., 2004
R. J. Scavuzzo; E. C. Rodabaugh
Full Description
Part 1: Piping System SIFs and Flexibility Analysis Criteria: Effect of Loading and Stress-Strain Curve on Stress Instensification FactorsThe basic objective of this investigation is to determine the effect of loading and the shape of the stress-strain curve on the stress intensification factors of Markl's fatigue evaluation method for metal piping. Markl's method is based on the fatigue testing of cantilever piping. Subsequent testing using a four-point loading showed that the S-N data were different from that predicted by the equation developed by Markl.
Previous analytical work on this topic [1] showed that these differences should occur from cantilever and fourpoint tests. The basic assumption in this analytical comparison is that strain-cycle correlations lead to the correct fatigue life. Given an alternating strain, both types of testing lead to the same predicting of fatigue life using strain-cycle correlations.
Part 2: Piping System SIFs and Flexibility Analysis Criteria: Investigation of Criteria Where Piping System Analysis is Not Required by ASME Piping Codes B31.1 and B31.3Report 2 investigates the background of the criteria, the various criteria equations, the associated "warnings" and the accuracy of the criteria equations.