軋延參數對於鋼帶精軋尾板側偏與鋼帶變形分析;Rolling Parameters Analyze Strip Tail Deviation and Deformation in Finish Mill

[[abstract]]在熱軋裡的精軋製程中尾板撞擊一直是熱軋線關注的問題之一。由於鋼帶在精軋區厚度較粗軋區薄再加上精軋區的軋延速度快，若鋼帶有任何不對稱外型或有軋機參數設定不良，就使整個精軋的軋延不穩定而使發生尾板撞擊的機率提高，發生尾板撞擊除了會損壞鋼帶也會導致軋輥表面受損進而影響。由熱軋線現場的操作鋼帶軋延經驗得知，造成鋼帶尾板撞擊的主因為鋼帶的尾端側偏，而造成鋼帶的尾端側偏的原因則為鋼帶的不對稱外型與軋機的組裝間隙，本研究主要分析鋼帶在精軋區的軋延參數對於鋼帶不對稱外型與鋼帶尾端側偏之影響，並且找出可能的先兆以有效降低尾板撞擊的機率。本研究利用有限元素法建立精軋機與鋼帶模型，模擬軋延時鋼帶的尾端側偏量，探討軋延參數對於鋼帶的不對稱外型變化與鋼帶尾端側偏之影響。並且結合模擬中的軋延參數與相對應的模擬結果建立鋼帶尾端側偏之迴歸模型，並將迴歸模型與模擬結果進行準確性驗證，若驗證結果接近則迴歸模型可使用於熱軋線場，本研究與熱軋線現場進行合作結合迴歸模型與精軋機調控系統，建立出比原先的調控系統更好的抑制尾板撞擊的機制，利用此系統讓熱軋線現場的操作可以更快擬定精軋機的操作參數條件以降低尾板撞擊發生機率，有效增加鋼帶產品的生產效率與良率。 In the finish mill during hot rolling, tail pinch phenomenon is an serious problem under highly concern. Since the strip thickness is thin and the rolling speed is high in finish mill, if there is any asymmetrical strip profile or any wrong setting of mill parameters, it is easily to cause milling instability in finish mill and to increase the probability of tail pinch. Tail pinch phenomenon not only damages the steel strip but also damage the surface of the rolls. Furthermore the production line would be interrupted due to changing rolls and removing the damaged strip which would seriously reduce the yield rate and deteriorate the production efficiency. According to the empirical data collected during finish mill, the cause of tail pinch phenomenon may be due to asymmetric deformation of strip end to a certain side. The reason for strip deformation to one side may be due to asymmetrical strip profile or rolling mill assembly gap. This research mainly analyzes the effect of rolling parameter on the asymmetrical strip profile and the strip end during finish milling and try to final an effective mechanism to reduce the tail pinch probability. Finite element analysis was applied deformation to establish a finish mill and strip model to simulate the possible strip end deformation which was affected by rolling parameters. A regression from the result of simulation could deduce mathematical model to applied to the correction of strip end deformation. The accuracy of the mathematical models will be verified by comparing with simulation results. A verified mathematical model can be then used for the finish mill line.The mathematical model in combined with the finishing mill on site control system to establish a better program control system to suppress the tail pinch phenomenon. Using this system the finish mill rolling parameters can be more efficiently corrected and the strip end deformation can be corrected and the production efficiency and the yield rate of steel strip products can be improved