During multi-pass conventional spinning, roller paths combined with the forward and the backward pass are usually used to improve the material formability. In order to understand the backward spinning process properly...During multi-pass conventional spinning, roller paths combined with the forward and the backward pass are usually used to improve the material formability. In order to understand the backward spinning process properly, the backward roller paths of hemispherical parts with aluminum alloy 2024-O are analyzed. Finite element model with parameterized conventional spinning roller paths, which are based on quadratic Bezier curves, is developed to explore the evolution of the stress, strain and thinning during the backward processes. Analysis of the simulation results reveals stress and strain features of backward pass spinning. According to the findings, the application of the backward pass can obviously improve the uniformity of wall thickness. Furthermore, references of the parameters in future backward path design are provided.展开更多
Roller pass is one of the key factors affecting the product quality in the retained mandrel rolling process. The metal flow condition of rolling deformation area was researched using the FEA （finite element analysis...Roller pass is one of the key factors affecting the product quality in the retained mandrel rolling process. The metal flow condition of rolling deformation area was researched using the FEA （finite element analysis） software Marc. The influences of the pass bottom radius, the sidewall radius, the sidewall angle, the roller shoulder fillet radius, as well as the roller gap on the rolling process under the conditions of different friction were discussed. Based on these results, the changes of the workpiece exit width, the mandrel axial force, the rolling force, and the rolling torque associated with various parameters were determined, which would provide the basis for designing the pass and determining the rolling condition reasonably.展开更多
高速线材原孔型系统主要有Ф5.5,6.0,6.5 mm 3个系列,导致轧制工艺参数不一致,增加轧辊、导卫和轧槽更换次数。通过孔型通用化设计,中轧、预精轧机组9H～17H孔型系统按现高线Ф6.0 mm孔型系列设计;精轧机组18#～26#孔型系统采用轧钢厂...高速线材原孔型系统主要有Ф5.5,6.0,6.5 mm 3个系列,导致轧制工艺参数不一致,增加轧辊、导卫和轧槽更换次数。通过孔型通用化设计,中轧、预精轧机组9H～17H孔型系统按现高线Ф6.0 mm孔型系列设计;精轧机组18#～26#孔型系统采用轧钢厂现有高线Ф6.0 mm孔型系列,但对26#孔型进行了改进;精轧机组27#～28#孔型系统仍采用轧钢厂现有高线Ф5.5,6.0,6.5 mm孔型系列。采用通用孔型系统对ER70S-6产品Ф5.5 mm规格进行试轧,预精轧、精轧机组料型控制不合理,精轧辊缝值偏小,多个机架辊缝值仅0.2～0.6 mm。对18#～26#孔型进行改进,采用改进后的通用孔型轧制的Ф6.5,8.0 mm HPB235盘条和Ф6.0 mm HRB400螺纹钢筋力学性能均满足GB 1499.2—2007的要求,每年可节约备件费用500万元,提高生产效率。展开更多
基金Project(2014CB046601)supported by the National Basic Research Program of ChinaProject(51675333)supported by the National Natural Science Foundation of China
文摘During multi-pass conventional spinning, roller paths combined with the forward and the backward pass are usually used to improve the material formability. In order to understand the backward spinning process properly, the backward roller paths of hemispherical parts with aluminum alloy 2024-O are analyzed. Finite element model with parameterized conventional spinning roller paths, which are based on quadratic Bezier curves, is developed to explore the evolution of the stress, strain and thinning during the backward processes. Analysis of the simulation results reveals stress and strain features of backward pass spinning. According to the findings, the application of the backward pass can obviously improve the uniformity of wall thickness. Furthermore, references of the parameters in future backward path design are provided.
基金Item Sponsored by National Natural Science Foundation of China (50675187)Natural Science Foundation for Youths of Hebei Province of China (E2010001161)
文摘Roller pass is one of the key factors affecting the product quality in the retained mandrel rolling process. The metal flow condition of rolling deformation area was researched using the FEA （finite element analysis） software Marc. The influences of the pass bottom radius, the sidewall radius, the sidewall angle, the roller shoulder fillet radius, as well as the roller gap on the rolling process under the conditions of different friction were discussed. Based on these results, the changes of the workpiece exit width, the mandrel axial force, the rolling force, and the rolling torque associated with various parameters were determined, which would provide the basis for designing the pass and determining the rolling condition reasonably.
文摘高速线材原孔型系统主要有Ф5.5,6.0,6.5 mm 3个系列,导致轧制工艺参数不一致,增加轧辊、导卫和轧槽更换次数。通过孔型通用化设计,中轧、预精轧机组9H～17H孔型系统按现高线Ф6.0 mm孔型系列设计;精轧机组18#～26#孔型系统采用轧钢厂现有高线Ф6.0 mm孔型系列,但对26#孔型进行了改进;精轧机组27#～28#孔型系统仍采用轧钢厂现有高线Ф5.5,6.0,6.5 mm孔型系列。采用通用孔型系统对ER70S-6产品Ф5.5 mm规格进行试轧,预精轧、精轧机组料型控制不合理,精轧辊缝值偏小,多个机架辊缝值仅0.2～0.6 mm。对18#～26#孔型进行改进,采用改进后的通用孔型轧制的Ф6.5,8.0 mm HPB235盘条和Ф6.0 mm HRB400螺纹钢筋力学性能均满足GB 1499.2—2007的要求,每年可节约备件费用500万元,提高生产效率。
