CAJ | 학술논문

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。
침대파문관현유제조공예존재한봉다、주기장、성본고、한봉구역출현확전렬문등결함，제출채용무심모축경선압성형파문관，병기우ABAQUS/Explicit평태건립료파문관무심모축경선압적삼유탄소성유한원모형。분석파문관축경선압과정중적응력응변분포규률표명，직벽구여사벽구상교처적원각시응력화소성응변집중구，해원각구역재선압과정중역산생후향과도감박화랍렬。채용단인소실험설계방법획득료공예삼수대성형질량적영향현저성화영향규률，병실험험증료수치모형결과적가고성화실용성。결과표명，심모전속대성형질량영향최대，심모전속증대시，공건직벽구경향척촌여파문중심고도적정도균회변차；선륜원각반경대성형질량유일정적영향，교소적선륜원각반경무법사재료완전체도소성상태이산생교대회탄，최종도치교대적궤하척촌정도편차；이교대적선륜진급속도용역재선륜전방산생금속퇴적，역사이선구발생과도감박종이영향성형질량。
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 .