Optimal Design and Analysis of Welding Bellow

• Main Authors: Rex Jiang, 江志民
• Other Authors: Eric Wen
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/10421221736691385889

碩士 === 聖約翰科技大學 === 自動化及機電整合研究所 === 95 === The graphical software Autocad 2000 is used for the cross-section design for the metal diaphragms of welding bellows in this study. Also a commercial finite element software ANSYS is employedas a tensile analysis with a constant displacement for a design-oriented bellow. Based on the tendency of analyzed results, there are not only some useful deduction that arcs’ radii of a bellow have directly influence on the maximum stress and stiffness, but the optimal arc parameters for bellow’s diaphragms are also obtained. Furthermore, the optimal design for the cross-section of diaphragms is proved by the comparison between import and homemade welding bellows. A 3-dimension model is introduced to the modal analysis of bellow vibration in which natural frequencies and vibrating modals could be observed. These important dynamic features shall be considered at the practical applications, i.e., to avoid the occurrence of resonant phenomena in pumps and a piping system. For the purpose of model validation, the 2-axis dynamic testing machine and a purpose-designed stiffness tester are individually implemented to perform the tensile experiment for welding bellows. According to the results of experiments and simulations, the difference among them could be easily detected for the investigation of error reason. Therefore, the proposed design for a stiffness tester of welding bellows is constructed through a systemic analysis. The contribution in this paper includes the simulation method and experimental procedure on the development of welding bellows, specific data referred to the R & D basis. Under the requirement of allowable stress and stiffness, a set of bellow arc parameters are adaptable for lower manufacturing cost and a longer fatigue life. Keywords: welding bellow, finite element method, stiffness, optimal design