B31 J SIF and k-Factor Test of Sweeplus®

Abstract

Formerly, an entire catalogue of 90 deg. branch connections called Sweeplus® was developed and accessed to mitigate acoustic induced vibration (AIV) in piping systems exposed to high frequency vibration. Parameters related to cyclic loading was completed on the Sweeplus® fitting to determine the stress intensification factor (SIF) and flexibility factor (k-factor), in accordance with the latest revision of ASME B31J-2017 code and reported in this paper. A Sweeplus® fitting was welded in a Markl test fixture and controlled through LabView software. The testing configuration and equipment were those used in Kahn test reported in WRC 329. K-factor tests were conducted for the in-plane thru both branch and header piping, and the out-of-plane thru branch. SIF tests were performed in the out-of-plane thru branch. The tests confirmed the SIF of Sweeplus® is less than one which means the fatigue life of Sweeplus® is significantly extended, not only under high frequency AIV excitation, but also under low frequency flow induced vibration (FIV) and thermal loading.