Papers by Author: Pei Ning Li

Abstract: Limit load test results from fourteen forged piping branch junctions are reported. Eight were uncracked. Three had outside, non-through wall cracks running parallel to the run pipe centerline at the flank and the others had crotch corner cracks among the selected specimens. The collapse behaviors such as bulging deformation at the side flanks of junctions with and without crack were depicted. Based on the experimental data, the relationships of limit load with structural dimension and crack size were then summarized and the existing solutions were evaluated in use of the test results.

Abstract: Systematic detailed non-linear finite element (FE) analysis are described for limit load interaction of piping branch junctions subjected to internal pressure and bending. The results show that for the tees with a small diameter ratio, the limit load interaction closes to the linear expression; as diameter ratio d/D increasing, the interaction relationship tends to parabolic equation; for the piping branch junction with diameter ratio equaling to unit, the limit load combinations is approximately quadratic. Compared to the individual limit bending value, internal pressure slightly increases the bending capability as it is in the range of 0.2£P/PL£0.4, especially for the cases of the main pipe with thinner wall. A closed limit load solution is obtained from the FE results through accommodating the geometrical parameter influence, and validated by using experimental results.