• Title/Summary/Keyword: Non-Idealized Circumferential Through-Wall Crack

Search Result 2, Processing Time 0.019 seconds

Evaluation of Crack Growth Estimation Parameters of Thick-Walled Cylinder with Non-Idealized Circumferential Through-Wall Cracks (비 이상화된 원주방향 관통균열이 존재하는 두꺼운 배관의 균열 성장 매개변수 계산)

  • Han, Tae-Song;Huh, Nam-Su;Park, Chi-Yong
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.33 no.2
    • /
    • pp.138-146
    • /
    • 2013
  • The present paper provides the elastic stress intensity factors(SIFs) of thick-walled cylinder with non-idealized circumferential through-wall cracks. For estimating these elastic SIFs, the systematic three-dimensional(3D) elastic finite element(FE) analyses were performed. In order to consider practical shape of thick-walled cylinder and non-idealized circumferential through-wall crack, the values of thickness of cylinder, reference crack length and crack length ratio were systematically varied. As for loading conditions, axial tension, global bending and internal pressure were considered. In particular, in order to calculate the SIFs of thick-walled cylinder with non-idealized circumferential through-wall crack from those of thick-walled cylinder with idealized circumferential through-wall crack, the correction factor representing the effect of non-idealized crack on the SIFs were proposed in this paper. The present results can be applied to accurately evaluate the rupture probabilities of nuclear piping considering actual crack growth behaviors.

An Engineering Method for Non-Linear Fracture Mechanics Analysis of Circumferential Through-Wall Cracked Pipes Under Internal Pressure (내압이 작용하는 원주방향 관통균열 배관의 비선형 파괴역학 해석법)

  • Huh, Nam-Su;Kim, Yun-Jae;Kim, Young-Jin
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.26 no.6
    • /
    • pp.1099-1106
    • /
    • 2002
  • This paper provides engineering J-integral and crack opening displacement (COD) estimation equations for circumferential through-wall cracked pipes under internal pressure and under combined internal pressure and bending. Based on selected 3-D finite element calculations for the circumferential through-wall cracked pipes under internal pressure using the idealized power law materials, the elastic and plastic influence functions for fully plastic J-integral and COD solutions are found as a function of the normalized crack length and the mean radius-to-thickness ratio. These developed GE/EPRI-type solutions are then re-formulated based on the enhanced reference stress method. Such re-formulation not only provides simpler equations for J-integral and COD estimations, but also can be easily extended to combined internal pressure and bending. The proposed equations are compared with elastic-plastic finite element results using actual stress-strain data, which shows overall excellent agreement.