弯曲角度与半径对Q345钢矩形管绕弯截面畸变的影响  

Influences of bending angle and radius on section distortion of Q345 steel rectangular tube in rotary-draw bending

作　　者：王翠竹 牛卫中[1] WANG Cui-zhu;NIU Wei-zhong(School of Mechanical Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学机电工程学院,甘肃兰州730070

出　　处：《塑性工程学报》2021年第8期112-118,共7页Journal of Plasticity Engineering

摘　　要：为了研究弯曲角α、弯曲半径和壁厚对Q345钢薄壁矩形管绕弯截面畸变的影响,利用Dynaform软件分别对两种壁厚的管坯在6种弯曲角度与5种弯曲半径下的绕弯成形进行仿真,得出每种情况下反映弯管截面畸变程度的3个畸变参数值。结果表明,Q345钢薄壁矩形管的绕弯成形存在由管坯尺寸和弯曲半径决定的临界弯曲角αc,弯管上的3个畸变参数值在α>αc时均保持稳定,不随α变化而变化,但当α<αc时其中至少1个畸变参数值随α增大而增大,而当α一定时则均随相对弯曲半径的减小而急剧增大;在管坯横截面宽度、高度、外圆角半径与壁厚之比不变的情况下,选用较大壁厚的管坯可以大幅降低相对弯曲半径较小弯管的最大宽度扩展率与最大中面高度缩减率。To study the influences of bending angleα,bending radius and wall thickness on the section distortion of Q345 steel thinwalled rectangular tube in rotary-draw bending,the rotary-draw bending of two kinds of tube blanks with different wall thicknesses was respectively simulated with six bending angles and five bending radii based on Dynaform software,and the values of three distortion parameters reflecting the section distortion degree of bent tubes were obtained under each circumstance.The results show that there exists a critical bending angleαc depending on the size of tube blank and bending radius in rotary-draw bending of Q345 steel thin-walled rectangular tube.The values of three distortion parameters of bent tube keep consistent asαvaries whenα>αc,but at least one increases asαincreases whenα<αc,and all increase rapidly with the decrease of relative bending radius whenαis certain.In the condition that the cross-section width,height and outer fillet radius to wall thickness ratio of tube blank are fixed,choosing tube with bigger wall thickness can greatly reduce the maximum width extension rate and maximum mid-plane height reduction rate of bent tube with small relative bending radius.

关 键 词：Q345钢 薄壁矩形管 绕弯 弯曲角度 弯曲半径 截面畸变 

分 类 号：TG386.43[金属学及工艺—金属压力加工]