Prediction of Buckling and Deformation Law of Pipe Fittings under Free Bending Based on Energy Method

doi:10.3901/JME.2024.20.162

Abstract

Abstract: The buckling and wrinkling phenomena in the process of tube manufacturing are predicted and studied by taking the tube formed by free bending as the research object. Firstly, the analysis model of free bending tube is established through the research of wrinkle prediction of pure bending tube forming, and the ripple function of free bending tube forming is deduced. Secondly, combined with the calculation formula of bending deformation energy of tube and the prediction formula of pure bending tube, the calculation formula of critical energy is obtained. Then, ABAQUS finite element simulation software is used for simulation calculation, and free bending critical energy calculation formula is used to predict the buckling and wrinkling phenomenon of tube and verify it. Finally, the prediction method of free bending buckling wrinkling is used to explore several factors affecting the free bending buckling wrinkling of pipe fittings. The results show that the bending radius, relative pipe diameter and unit length twist angle are the factors that affect the occurrence of buckling and wrinkling in the precision forming process of thin-walled tube NC bending. The research results have created conditions for the determination and optimization of parameters in the free bending forming process.

Key words: free bending, instability wrinkling, energy method, influencing factors

CLC Number:

V264

GAO Sheng, WU Jianjun, YAN Jing, ZHANG Rongxia, YU Zhongping, LIU Long. Prediction of Buckling and Deformation Law of Pipe Fittings under Free Bending Based on Energy Method[J]. Journal of Mechanical Engineering, 2024, 60(20): 162-172.

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