摘要
三旋轮非对称强旋在大型筒形件热旋工艺中具有独特的优势,然而关于非对称强旋的研究开展较少。文章建立了三旋轮非对称强旋的有限元计算模型,通过对非对称强旋的三维刚粘塑性有限元数值模拟,揭示了非对称强旋的变形特点。研究结果表明,旋轮的非对称分布使得应力应变场沿周向呈非周期性分布,尽管旋轮Ⅱ和Ⅲ在空间位置上具有对称性,但是其接触区的应力应变速率分布却有较大差别,反倒是旋轮Ⅰ和Ⅱ的接触区应力应变速率分布颇为相近。旋轮的非对称分布使得旋压过程中不同旋轮相应的接触区大小不同,从而致使旋轮Ⅲ的塑性区小于旋轮Ⅰ和Ⅱ的塑性区,相应地旋轮Ⅲ的旋压力小于旋轮Ⅰ和Ⅱ的旋压力。变形场的分布能合理解释旋压时产生的伸长、胀径及隆起等现象。
Tube spinning with non-symmetric distribution of three rollers has special advantages in hot spinning of large-diameter tubular workpieces, but there is little information available in the literature concerning non-symmetric spinning. In the present study, the FEM model of non-symmetric spinning has been established and the spinning process has been simulated, which reveals deformation characteristics of non-symmetric tube spinning. The results show that non-symmetric distribution of three rollers makes the stress and strain field distributed not periodically along circumferential direction on the surface of tube billet. Although roller Ⅱ and Ⅲ have symmetric relationship the distribution of stress and strain rate near around the contact zone under the two rollers are obviously different. However, the distribution of stress and strain rate under roller Ⅰ and Ⅱ are similar to each other. The non-symmetric distribution of three rollers makes the area of roller contacting region different, which causes the plastic zone of roller Ⅲ smaller than roller Ⅰ and Ⅱ. Correspondingly the spinning force of roller Ⅲ is smaller than that of roller Ⅰ and Ⅱ The distribution of deformation field can explain some phenomena reasonably such as axial extending, diameter growth and pileup during spinning.
出处
《塑性工程学报》
EI
CAS
CSCD
北大核心
2007年第4期44-48,共5页
Journal of Plasticity Engineering
关键词
筒形件
非对称旋压
有限元
应力应变场
旋压力
tubular workpiece
non-symmetric spinning
FEM
stress and strain field
spinning force
