Numerical Study on the Strength Safety of High Pressure Gas Cylinder

고압가스 압력용기의 강도안전성에 관한 수치해석적 연구

  • Kim, Chung-Kyun (Research Center for Tribology, Mechatronics and Energy Technology Hongik University) ;
  • Kim, Seung-Chul (Research Center for Tribology, Mechatronics and Energy Technology Hongik University)
  • 김청균 (홍익대학교 기계.시스템디자인공학과) ;
  • 김승철 (홍익대학교 기계.시스템디자인공학과)
  • Received : 2010.02.04
  • Accepted : 2010.03.31
  • Published : 2010.04.30

Abstract

The strength safety of high pressure gas cylinder has been analyzed by using a finite element method. In this study, the internal gas pressures of a steel bombe include a service charging pressure of $9kg/cm^2$, high limit charging pressure of $18.6kg/cm^2$, high limit of safety valve operation pressure $24.5kg/cm^2$, and hydraulic testing pressure of $34.5kg/cm^2$. The computed FEM results indicate that the strength safety for a service charging pressure of $9kg/cm^2$ and high limit charging pressure of $18.6kg/cm^2$ is safe because the stress of a gas cylinder is within yield strength of steel. But the stress for a hydraulic testing pressure of $34.5kg/cm^2$ sufficiently exceeds the yield strength and remains under the tensile strength. If the hydraulic testing pressures frequently apply to the gas cylinder, the bombe may be fractured because a fatigue residual stress is accumulated on the lower round end plate due to a plastic deformation. The computed results show that the concentrated force in which is applied on a skirt zone does not affect to the lower round end plate, and the most weak zone of a bombe is a middle part of a lower round end plate between a bombe body and a skirt for a gas pressure. Thus, the FEM results show that the profile of a lower round end plate is an important design parameter of a high pressure gas cylinder.

Acknowledgement

Supported by : 홍익대학교

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