摘要
针对波纹管现有制造工艺存在焊缝多、周期长、成本高、焊缝区易出现扩展裂纹等缺陷,提出采用无芯模缩颈旋压成形波纹管,并基于ABAQUS/Explicit平台建立了波纹管无芯模缩径旋压的三维弹塑性有限元模型。分析波纹管缩径旋压过程中的应力应变分布规律表明,直壁区与斜壁区相交处的圆角是应力和塑性应变集中区,该圆角区域在旋压过程中易产生厚向过度减薄和拉裂。采用单因素实验设计方法获得了工艺参数对成形质量的影响显著性和影响规律,并实验验证了数值模型结果的可靠性和实用性。结果表明,芯模转速对成形质量影响最大,芯模转速增大时,工件直壁区径向尺寸与波纹中心高度的精度均会变差;旋轮圆角半径对成形质量有一定的影响,较小的旋轮圆角半径无法使材料完全达到塑性状态而产生较大回弹,最终导致较大的几何尺寸精度偏差;而较大的旋轮进给速度容易在旋轮前方产生金属堆积,易使已旋区发生过度减薄从而影响成形质量。
Aluminum corrugated pipe has been applied in broad areas including aerospace ,petrol industries due to its lightweight and good corrosion resistance .The existing welding processing method of corrugated pipes has many disadvantages ,such as weld seam ,long time of manufacturing ,high cost ,and sensitivity of weld areas to cracks ,etc .Thus this paper proposed a method using mandreless neck-spinning forming process to manufacture the corrugated pipes .Based on ABAQUS/Explicit ,an elastic-plastic fi-nite element model for the mandreless neck-spinning process is established .Stress and strain distributions during the spinning process are analyzed ,and the results show that the fillet between the straight wall area and the inclined wall area is the stress-strain concentration area ,which has great effect on the thickness reduction and crack of the corrugated pipe .Furthermore ,the sin-gle factor experiments were designed to study the effects of process parameters on the forming quality .Finally ,the experiments have been carried out to verify the feasibility of this spinning method and simulations .The results show that ：the mandrel speed is the most influential factor on the forming quality ,a big rotation speed of mandrel leads to a bad wall straightness and inaccurate di-mension of ripple area ;Roller fillet radius also has a significant influence on the forming quality ,and a small fillet radius results in the incomplete plastic state and a considerate amount of springback at the end of the process .A relatively big feed rate would lead to a large accumulation of material in front of the roller and severe reduction of wall thickness during the spinning process .
出处
《塑性工程学报》
CAS
CSCD
北大核心
2014年第2期108-115,共8页
Journal of Plasticity Engineering
基金
国家自然科学基金优秀青年科学基金资助项目(51222509)
国防科工局技术基础科研项目
关键词
波纹管
缩径旋压
有限元仿真
工艺参数
corrugated pipe
neck-spinning
finite element simulation
process parameter optimization
