Effect of Restraint of Pressure Induced Bending on Crack Opening Evaluation for Circumferential Through-Wall Cracked Pipe

원주방향 관통균열 배관의 균열열림 평가에 미치는 압력유기굽힘의 구속효과

  • Published : 2001.11.01


The effects of restraint of pressure induced bending(PIB) on crack opening for circumferential through-wall crack in a pipe were investigated. In this study, the elastic and elastic-plastic finite element analyses were performed to evaluate crack opening displacement(COD) for various restraint conditions and crack size. The results showed the restraint of PIB decreased crack opening for a given crack size and tensile stress, and the decrease in crack opening was considerable for large crack and short restraint length. A1so, the effect was more significant in tole results of elastic-plastic analysis compared with in the elastic analysis results. In the elastic-plastic analysis results, tole restraint effect was increased with increasing applied tensile stress corresponding to internal pressure. Additionally, the restraint effect on COD was independent on the variation in pipe diameter and decreased with increasing pipe thickness, and It depended on not total restraint length but shorter restraint length for non-symmetrically restrained.


Pressure Induced Bending;Leak-Before-Break;Through-wall Crack;Crack Opening Displacement


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