本文選題：帶鋼 + 起筋��； 參考：《北京科技大學》2016年博士論文

【摘要】：隨著帶鋼生產(chǎn)工藝、裝備及控制技術(shù)的不斷發(fā)展,帶鋼板形質(zhì)量得到明顯提高,達到了較高的水平。然而,生產(chǎn)中經(jīng)常出現(xiàn)的起筋現(xiàn)象制約著帶鋼質(zhì)量的進一步提升。由于導致帶鋼起筋的影響因素眾多,因此,從理論上對起筋問題進行定量分析十分困難。目前,國內(nèi)外對于帶鋼起筋問題的研究主要集中在起筋量的測量和預測方面,而對帶鋼起筋機理和控制方法的研究較少,對于起筋鋼卷開卷后出現(xiàn)的局部浪形也無法給出合理的解釋。因此,對起筋機理和控制策略的研究在學術(shù)和生產(chǎn)實踐中具有重大的意義。本論文基于數(shù)值和解析方法,對軋制及卷取過程中帶鋼的起筋機理和控制策略進行深入研究,取得了以下創(chuàng)新性成果：(1)為了分析帶鋼的起筋機理,借鑒三維彈塑性變形的處理思想,建立了鋼卷彈塑性應力場和起筋量計算模型。針對局部高點和局部浪形的不同特性,從應力角度分別分析了兩種缺陷在卷取過程導致帶鋼起筋的根本原因,并分析了各影響因素對起筋量的影響,得到了局部高點引起的帶鋼起筋首先產(chǎn)生在鋼卷最外層、局部浪形導致的帶鋼起筋首先產(chǎn)生在鋼卷最內(nèi)層的重要結(jié)論。(2)為了研究帶鋼起筋的臨界應力及其與各影響因素間的關(guān)系,根據(jù)導致帶鋼起筋的局部高點和局部浪形的不同特點,基于應力函數(shù)假設和S.Timoshenko最小功原理,分別獲得了首先產(chǎn)生起筋的鋼卷最外層和最內(nèi)層帶鋼的應力場分布,并基于伽遼金虛位移原理首次建立了起筋臨界應力求解模型,分析了起筋臨界應力與其影響因素間的關(guān)系,為帶鋼起筋控制提供了理論依據(jù)�；诿兹闺p向應力屈服準則建立了起筋量彈性極限的判定方法,并將二次攝動法引入到鋼卷起筋后屈曲變形分析中,獲得了后屈曲變形過程鋼卷應力場與起筋撓度間的關(guān)系,完善了帶鋼起筋屈曲變形理論。(3)分析了各影響因素對冷軋過程帶鋼局部變形的影響,并建立了冷軋帶鋼屈曲失穩(wěn)計算模型,為軋制中最大程度降低局部缺陷而不產(chǎn)生局部浪形提供了依據(jù)。綜合起筋量模型、起筋臨界應力模型、軋輥-軋件快速耦合變形模型和屈曲失穩(wěn)求解模型,建立了冷軋原料局部高點極限值求解方法和基于PSODE算法的帶鋼起筋控制策略,形成了冷軋原料和冷軋過程兩個層面的完整的起筋控制策略,為解決帶鋼起筋問題提供了技術(shù)支持。系統(tǒng)投入使用前后連續(xù)熱鍍鋅生產(chǎn)線彩涂基料起筋回退率由原15.8%降低到0.18%,對提高帶鋼板形質(zhì)量和工業(yè)生產(chǎn)具有重要的應用價值。
[Abstract]:With the continuous development of strip production technology, equipment and control technology, the strip shape quality has been obviously improved and reached a higher level. However, the reinforcement phenomenon often appears in production restricts the further improvement of strip quality. Because there are many factors that influence the steel strip reinforcement, it is very difficult to quantitatively analyze the reinforcement problem theoretically. At present, the domestic and foreign research on strip reinforcement is mainly focused on the measurement and prediction of the amount of reinforcement, but the research on the mechanism and control method of strip reinforcement is less. It is impossible to give a reasonable explanation for the local wave shape of steel coils after unwinding. Therefore, the research on reinforcement mechanism and control strategy is of great significance in academic and production practice. In this paper, based on numerical and analytical methods, the reinforcement mechanism and control strategy of strip during rolling and coiling are deeply studied. The following innovative results are obtained: 1) in order to analyze the mechanism of strip reinforcement, Based on the theory of three dimensional elastoplastic deformation, a calculation model of elastic-plastic stress field and stiffening capacity of steel coil is established. According to the different characteristics of local high point and local wave shape, the fundamental causes of two kinds of defects leading to strip reinforcement in coiling process are analyzed from the stress angle, and the influence factors on the amount of reinforcement are analyzed. It is obtained that the strip hoist caused by the local high point is first produced in the outermost layer of the coil. In order to study the critical stress and the relationship between the critical stress and the influence factors, according to the different characteristics of the local high point and the local wave shape, Based on the assumption of stress function and the principle of S.Timoshenko minimum work, the distribution of stress field in the outermost and innermost steel strips with the first reinforcement is obtained, and the solution model of critical stress is established for the first time on the basis of Galerkin's virtual displacement principle. The relationship between the critical stress and its influencing factors is analyzed, which provides a theoretical basis for strip reinforcement control. Based on the Mises bidirectional stress yield criterion, the method of determining the elastic limit of the reinforcement is established, and the quadratic perturbation method is introduced to the analysis of the post-buckling deformation of the steel coil. The relationship between the stress field of the steel coil and the deflection of the stiffener during the post-buckling deformation is obtained. The buckling deformation theory of steel strip is improved. The influence factors on the local deformation of strip during cold rolling are analyzed, and the calculation model of buckling instability of cold rolled strip is established. It provides a basis for minimizing local defects without producing local waves in rolling. Based on the reinforcement model, the critical stress model, the fast coupling deformation model and the buckling instability solution model, the local limit value of cold rolling material and the control strategy of strip reinforcement based on PSODE algorithm are established. A complete reinforcement control strategy for cold rolling raw material and cold rolling process is formed, which provides technical support for solving the problem of strip reinforcement. Before and after the system is put into use, the backing back rate of color coating base material in continuous hot dip galvanizing production line is reduced from 15.8% to 0.18%, which has important application value for improving strip shape quality and industrial production.
【學位授予單位】：北京科技大學
【學位級別】：博士
【學位授予年份】：2016
【分類號】：TG335.5

【參考文獻】

相關(guān)期刊論文 前1條

1 張國河;;帶鋼“起筋”成因分析與對策[J];鞍鋼技術(shù);2007年05期

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本文編號：1821216