【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。更多还原

【Abstract】 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.更多还原