摘要
对某两层四波Ω形波纹管的液压成形过程进行了有限元数值模拟,分析各层管坯成形后的应力场和应变场分布以及波高方向鼓波高度和壁厚减薄率。结果发现,波纹管液压成形过程中,卸载前最大等效应力出现在大圆弧上,卸载后最大等效应力出现在大圆弧与小圆弧过渡处;波纹管在液压成形过程中,最大塑性变形出现在波峰上,最大塑性应变达27%;波纹管液压成形过程中壁厚减薄严重,波峰处可达17%以上。将模拟所得的波形参数与实际液压成形结果相对比,成形厚度、波高方向鼓波高度等参数的相对误差均小于5%,说明采用有限元法对Ω形波纹管液压成形进行数值模拟是有效、可信的。
Finite element method was employed to simulate the hydraulic forming process of a two-layered and four-corrugated Ω-shape bellows. The stress and strain field distributions after the forming of each lay- er of tube billets were analyzed, and corrugation height and wall thickness reduction rate in the direction of corrugation height were obtained. From the results, it was found that the maximum equivalent stress （Mises stress） before unloading occurred at the large arc, and the maximum equivalent stress （Mises stress） after unloading occurred at the transition area between the large arc and small arc;during the forming process of the bellows, the maximum plastic deformation appeared at the bellows peak with the plastic strain being as high as 27%, and the wall thickness reduction was serious and the reduction rate could be more than 17% at the bellows peak. By comparing the corrugation shape parameters obtained through simulation with the actual hydraulic forming results, it was found that the relative errors of param- eters such as forming thickness, corrugation height in direction of corrugation height were all less than 5% ,indicating that use of finite element method for numerical simulation of the hydraulic forming of Ω-shaped bellows is effective and credible.
作者
李慧芳
叶梦思
钱才富
王友刚
LI Hui - fang;YE Meng - si;QIAN Cai - fu;WANG You - gang(College of Mechanical and Electrical Engineering,Beijing University of Chemical Technology,Beijing 100029,China;Dalian Yiduo Piping Co.,Ltd.,Dalian 116318,China)
出处
《压力容器》
北大核心
2018年第6期70-77,共8页
Pressure Vessel Technology
关键词
Ω形波纹管
液压成形
数值模拟
厚度减薄
Ω-shaped bellows
hydroforming
numerical simulation
wall thickness reduction
