The ultimate ductile state model for a pipe with an axial through crack

Abstract

A statistically admissible solution has been constructed for a pipe with an axial through crack. The boundaries of the limit region have been obtained and the strength conditions on its boundary have been formulated. The extension of the distribution of forces and moments beyond the limit region boundary has been substantiated. The results obtained for a pipe with closed ends are in fair agreement with the experimental data. The influence of the axial force and the property anisotropy upon the fracture stress has been studied. The possibility of considering several cracks is analysed.

Residual strength of pipelines with dents

“…Apparently, it is impossible to modify these formulas experimentally in order to estimate strength with a greater number of input parameters (different types of cracks, the presence of additional axial stresses in a pipe, the consideration of the third dimension (width) in a defect under study, close location of defects, etc.). In our opinion, just a theoretical analysis can prompt the required solutions [6][7][8][9].The worst situation has arisen with defects of the dent type. Normative documents used for their analysis are based sooner on the subjective perceptions of the designers than on a detailed consideration.…”