薄板冷连轧自激振动的临界轧制速度研究

发布时间：2018-02-27 22:57

本文关键词： 轧机连续轧制自激振动稳定性临界轧制速度　出处：《机械工程学报》2017年12期 　论文类型：期刊论文

【摘要】：轧机是典型的结构与工艺相互耦合的复杂动力学系统,在内源反馈激励作用下驱动能量在某种条件下被转换为结构的振动能量而引起自激振动。轧制速度既是生产效能的直接衡量指标,也是触发轧机振动失稳的关键因素,因此对临界轧制速度的研究对于预测和抑制自激振动的产生具有重要意义。考虑轧制界面的等效弹塑性刚度,建立某薄板轧制六辊轧机的8自由度非对称结构模型,基于平面应变假设运用SLAB理论计算法建立轧制过程模型,通过轧制力计算值和实测值的比较对模型有效性进行验证,并运用TALOR展开得到力能参数的增量模型,从而建立结构-工艺相耦合的动力学模型。通过对模型的LAPLACE变换得到S域特征方程,应用ROUTH稳定性准则得到系统的失稳条件以及产生自激振动的速度阈值,分析工艺参数对其影响规律,并进而提出工艺规程的制订及优化途径。将计算分析结果与生产现场实际情况相结合,对轧制过程升速阶段和匀速运行阶段的典型振动现象及抑制策略进行仿真再现,并从临界轧制速度与自激失稳振动的关系对其进行解释。研究结果表明临界轧制速度是评价轧机振动及轧制稳定性的重要指标,通过连轧机架间的压下规程配比和工艺条件优化可以提高临界轧制速度,从而实现薄板轧机的高速稳定轧制。
[Abstract]:Rolling mill is a typical complex dynamic system which is coupled with process and structure. The driving energy is converted to the vibration energy of the structure under some conditions under internal feedback excitation, which causes self-excited vibration. Rolling speed is not only a direct measure of production efficiency, but also a key factor to trigger the vibration instability of rolling mill. Therefore, the study of critical rolling speed is of great significance for prediction and suppression of self-excited vibration. Considering the equivalent elastic-plastic stiffness of rolling interface, an 8-DOF asymmetric structure model of a six-high rolling mill for thin plate rolling is established. Based on the assumption of plane strain, the rolling process model is established by using SLAB theory. The validity of the model is verified by comparing the calculated value of rolling force with the measured value, and the incremental model of force and energy parameter is obtained by TALOR expansion. The characteristic equations in S domain are obtained by the LAPLACE transformation of the model, and the instability conditions of the system and the velocity threshold of the self-excited vibration are obtained by using the ROUTH stability criterion. The influence of process parameters on the process parameters is analyzed, and the formulation and optimization of process rules are put forward. The results of calculation and analysis are combined with the actual conditions of production site. The typical vibration phenomena and suppression strategies of rolling process in the stage of increasing speed and running at uniform speed are simulated and reproduced. The relationship between the critical rolling speed and the self-excited instability vibration is explained. The results show that the critical rolling speed is an important index to evaluate the rolling mill vibration and rolling stability. The critical rolling speed can be improved by optimizing the ratio of rolling schedule and technological conditions between the stand of continuous rolling mill, and thus the high speed and stable rolling of thin plate mill can be realized.
【作者单位】：北京科技大学机械工程学院;
【基金】：2014国家智能制造装备发展专项课题“高精度面板智能化冷连轧生产线” 国家自然科学基金(51175035) 北京高校青年英才计划(YETP0367) 中央高校基本科研业务费(FRF-BR-14-006A)资助项目
【分类号】：TG333.72

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