Xie Dan, Ouyang Qiu-Yue, He Luo-Yu, Xu Wu-Jiao
College of Material Science and Engineering, Chongqing University, Chongqing 400044, China.
Chongqing Key Laboratory of Advanced Mold Intelligent Manufacturing, Chongqing 400044, China.
Materials (Basel). 2023 Apr 26;16(9):3383. doi: 10.3390/ma16093383.
Due to the large wall thickness difference and serious instability in the large-scale ring rolling process, most studies on the feed curve are not suitable for a large-scale ring. The production cost of the large-scale ring is high, and if plastic instability occurs, it will cause a great waste of resources. Therefore, in this study, a staged feed strategy based on the evolution of ring instability is proposed with the objective of controlling the rolling stability of a large-scale ring. Firstly, based on the law of rolling instability evolution, the rolling stage during the rolling process is divided. Secondly, the coordination of all rolling stages is proposed as a factor to design the feed curve. The feed scheme is determined using the central composite design (CCD) method, and then the established mathematical model is applied to obtain the radial feed curves of a large-scale flat ring with a 5 m diameter for different schemes. Next, the designed feed curve was submitted to finite element method (FEM) simulation. According to the FE simulation results, a rolling map for controlling roundness error, eccentricity and vibration is established. Finally, the feed curve in the stable region is input to the FE simulation and the production trial to obtain the results of roundness error, eccentricity and vibration. A comparison of the simulation and production trial results shows that they are in good agreement, which proves the reliability of the feed curve designed based on the stable rolling region in the roll map. Moreover, the machining amount for both the simulation and production trial is below the maximum machined value.
由于大型环件轧制过程中壁厚差大且不稳定严重，大多数关于进给曲线的研究并不适用于大型环件。大型环件的生产成本高，若发生塑性失稳，会造成极大的资源浪费。因此，本研究提出一种基于环件失稳演变的分段进给策略，旨在控制大型环件的轧制稳定性。首先，基于轧制失稳演变规律，划分轧制过程中的轧制阶段。其次，提出各轧制阶段的协调性作为设计进给曲线的一个因素。采用中心复合设计（CCD）方法确定进给方案，然后应用所建立的数学模型得到不同方案下直径为5m的大型扁平环件的径向进给曲线。接着，将设计的进给曲线提交至有限元方法（FEM）模拟。根据有限元模拟结果，建立控制圆度误差、偏心度和振动的轧制图谱。最后，将稳定区域内的进给曲线输入有限元模拟和生产试验，以获得圆度误差、偏心度和振动的结果。模拟结果与生产试验结果的比较表明二者吻合良好，这证明了基于轧制图谱中稳定轧制区域设计的进给曲线的可靠性。此外，模拟和生产试验的加工量均低于最大加工值。
