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Effect of Bend Angle on the Collapse Behavior of Locally Wall Thinned Pipe Bends

감육 곡관의 붕괴거동에 미치는 곡관 굽힘각의 영향

  • 나만균 (조선대학교 원자력공학과) ;
  • 김진원 (조선대학교 원자력공학과)
  • Published : 2006.10.01

Abstract

The purpose of this study is to investigate the effect of bend angle on the collapse behavior of locally wall thinned pipe bends. For this purpose, the present study performed three-dimensional finite element analysis on the 30-, 60-, and 90-degree pipe bends with local wall thinning at the center of intrados, extrados, and crown, and evaluated the collapse moment for different thinning dimensions under closing- and opening-mode bending with a constant internal pressure. The results showed that, for intrados and extrados wall thinning, the reduction in the collapse moment due to local wall thinning became significant with decreasing bend angle of pipe bends. This effect of bend angle was enhanced with increasing thinning dimensions, and it was clearer fur opening-mode bending than for closing-mode bending. For crown wall thinning, however, the effect of bend angle was unclear and was less sensitive to the change of wall thinning shapes.

Keywords

Bend Angle;Pipe Bend;Collapse Behavior;Local Wall Thinning

References

  1. Shalaby, M. A. and Younan, M. Y. A., 1999, 'Limit Loads for Pipe Elbows Subjected to In-Plane Opening Moments and Internal Pressure,' J. of Press. Ves. Tech., Vol. 121, pp. 17-23 https://doi.org/10.1115/1.2883661
  2. Chattopadhyay, l, 2002, 'The Effect of Internal Pressure on In-Plane Collapse Moment of Elbow,' Nucl. Eng. & Des., Vol. 212, pp. 133-144 https://doi.org/10.1016/S0029-5493(01)00468-X
  3. Chexal, B., Horowitz, l, Dooley, B., Millett, P., Wood, C., and Jones, R., 1998, 'Flow-Accelerated Corrosion in Power Plant,' EPRI/TR-106611-R2
  4. Korea Atomic Energy Research Institute, 2001, 'Development of Enhanced Safety Technology for Operating PHWR Plant,' KAERI/RR-2226/2001, Final Report
  5. Ahn, S. H., Nam, K. W., Yoo, Y. S., K., Ando, K., Ii, S. H., Ishiwata, M., and Hasegawa, K., 2002, 'Fracture Behavior of Straight Pipe and Elbow with Local Wall Thinning,' Nuc/. Eng. & Des., Vol. 211, pp. 91-103 https://doi.org/10.1016/S0029-5493(01)00447-2
  6. Kim, J. W., Kim, T. S., Park, C. Y., 2004, 'An Evaluation of The Effect of Local Wall Thinning Defect on the Collapse Moment of Elbow,' Trans. of KSME (A), Vol. 28, No.4, pp. 402-409
  7. Kim, J. W and Lee, J. G., 'Effect of Circumferential Location of Local Wall Thinning Defect on the Collapse Moment of Elbow,' J. of Kor. Soc. of Safety, Vol. 20, No.1, pp. 55-61
  8. Kim, J. W, Na, M. G., and Park, C. Y., 2005, 'Development of Failure Pressure Evaluation Model for Internally Wall Thinned Piping Components,' Trans. of KSME (A), Vol. 29, No. 7, pp. 947-954
  9. Hibbitt, Karlson and Sorensen Inc., 2002, 'ABAQUS ver. 6.2 User's Manual'
  10. Yahiaoui, K., Moffat, D. G. and Moreton, D. N., 2000, 'Piping Elbows with Cracks, Part 2: Global Finite Element and Experimental Plastic Loads Under Opening Bending,' J. Strain Anal., Vol. 35, pp. 47-57 https://doi.org/10.1243/0309324001514008
  11. American Society of Mechanical Engineer, ASME B&PV Code Sec. VIII, 1995 ed., 'Rules for Construction of Pressure Vessels'
  12. Park, B. G., Kim, Y. I, and Kim, Y. J., 2005, 'Limit Load Solutions for Pipes with Local Wall Thinning Based on Finite Element Limit Analysis,' Proc. of KSME Spring Meeting, pp. 231- 236