不等辊距钢筋矫直机参数优化设计及仿真实验研究

发布时间：2018-04-27 18:55

本文选题：结构参数 + 优化设计　；参考：《沈阳建筑大学》2015年硕士论文

【摘要】：矫直作为一种精整技术,其重要性日益突出,已成为工业发展不可或缺的分支。不等辊距矫直是一种先进的矫直技术,融合了等辊距和变辊距矫直技术的特点,矫直精度高、矫直规格品种多、操作简便、应用前景广阔。因此有必要对不等辊距矫直系统展开理论研究和应用实践,为企业应用做技术积累。矫直过程的准确理论解析是进行现场生产和控制的基本前提条件。本文根据钢筋矫直原理,分析钢筋在矫直过程中的受力和变形情况,了解钢筋被不等辊距矫直机逐渐矫直的过程。依据金属的弹塑性弯曲理论,研究一微小段钢筋矫直过程中任意方向上的应力、应变、弯矩、回弹情况,找出原始曲率比、反弯曲率比与它们的关系,为后面的参数设计计算与仿真研究铺垫理论基础。本文根据不等辊距矫直技术的特点,确定矫直方案。根据接触应力和咬入条件确定各个矫直参数范围,以总矫直力之和最小为目标函数,运用MATLAB中fmincon函数对辊距实现优化设计,这种方式使矫直机处于一种较佳的状态,拥有较佳的矫直效果,为不等辊距矫直机的设计及研发提供了有价值的参考。进而得到各结构参数及矫直力理论计算值。同时建立起曲率比和压弯挠度之间的关系,计算出不同原始曲率比、不同钢筋直径下各辊的压下量,找到它们之间的配比关系与变化规律。这种方式使在实际操作中给定压下量变得更容易,效率更高,矫直精度更高。通过对钢筋辊式矫直过程中的矫直工艺参数的研究,找到矫直不同直径钢筋时合理的矫直参数,保证钢筋矫直质量,为实际生产中矫直参数的制定、优化和矫直工艺提供科学依据。本文按照优化后的辊距、辊径、辊长和相应的压下量,应用ANSYS/LS-DYNA软件建立矫直系统动力学模型,进行Φ8、Φ10、Φ12mm钢筋的矫直仿真研究,查看矫直力变化情况、直线度大小、残余应力分布,检验优化设计效果,仿真模型与方法的合理性,亦不等辊距钢筋矫直机的矫直质量,并与等辊距钢筋矫直机矫直效果作比较,进而验证不等辊距钢筋矫直机的优势。掌握该项仿真技术可以提高产品的生产效率,降低钢筋矫直的成本,对于认识和掌握钢筋矫直的变形机理,进一步完善和发展辊式矫直理论,提供了新的研究手段。之后通过不等辊距钢筋矫直机对Φ8、Φ10mm钢筋进行的矫直实验数据分析计算,和等辊距钢筋矫直机实验数据对比,同样验证不等辊距钢筋矫直机矫直质量更优,这为研究方法的实践与推广起到了决定性作用。同时,仿真与实验研究具体形象地反映了等辊距与不等辊距矫直机的优缺点,有利于操作中更好地利用它们,更好地推广优势设备。本文采用的理论和仿真、实验相结合的分析方法,就是对未来矫直技术研究的良好尝试。对矫直关键技术的研究,具有一定的理论和现实意义。
[Abstract]:Straightening as a finishing technology, its importance is increasingly prominent, has become an indispensable branch of industrial development. Unequal roll spacing straightening is an advanced straightening technology, which combines the characteristics of equal roll spacing and variable roll spacing straightening technology. It has high straightening accuracy, many kinds of straightening specifications, simple operation and wide application prospect. Therefore, it is necessary to carry out theoretical research and application practice on the unequal roll spacing straightening system to accumulate technology for enterprise application. The accurate theoretical analysis of straightening process is the basic prerequisite for field production and control. According to the principle of steel bar straightening, the stress and deformation of steel bar in the process of straightening are analyzed, and the process of steel bar being straightened gradually by unequal roller straightener is understood. Based on the elastic-plastic bending theory of metal, the stress, strain, bending moment and springback in any direction in the process of straightening a small section of steel bar are studied, and the relationship between the original curvature ratio and the ratio of reverse bending rate is found out. It lays the theoretical foundation for the design, calculation and simulation of the parameters. According to the characteristics of unequal roll spacing straightening technology, the straightening scheme is determined in this paper. According to the contact stress and bite condition, the range of straightening parameters is determined. The minimum sum of total straightening force is taken as the objective function, and the fmincon function in MATLAB is used to realize the optimum design of roll spacing, which makes the straightener in a better state. It has better straightening effect and provides valuable reference for the design and development of unequal roller straightener. Then the calculated values of structure parameters and straightening force theory are obtained. At the same time, the relationship between curvature ratio and bending deflection is established, and the reduction of each roll under different original curvature ratio and different steel bar diameter is calculated. This approach makes it easier, more efficient and more accurate to give a reduction in practice. Through the research of the straightening process parameters in the steel bar roller straightening process, the reasonable straightening parameters can be found when straightening steel bars with different diameters, so as to ensure the straightening quality of the steel bars, and make the straightening parameters for the actual production. Optimize and straighten the technology to provide scientific basis. According to the optimized roll spacing, roll diameter, roll length and corresponding reduction, the dynamic model of straightening system is established by using ANSYS/LS-DYNA software, and the straightening simulation of 桅 8, 桅 10, 桅 12mm steel bar is carried out, and the changes of straightening force, straightness and residual stress distribution are observed. The optimization design effect, the rationality of simulation model and method, and the straightening quality of unequal roller spacing steel bar straightener are tested and compared with that of equal roll distance steel bar straightening machine, and the advantages of unequal roll spacing steel bar straightening machine are verified. Mastering the simulation technology can improve the production efficiency and reduce the cost of steel bar straightening. It provides a new research method for understanding and mastering the deformation mechanism of steel bar straightening and further improving and developing the roller straightening theory. After that, by analyzing and calculating the experimental data of 桅 8, 桅 10mm steel bar straightening machine with unequal roller spacing steel bar straightening machine, and comparing with the experimental data of equal roll spacing steel bar straightening machine, it is also proved that the straightening quality of unequal roll spacing steel bar straightening machine is better. This has played a decisive role in the practice and popularization of research methods. At the same time, the simulation and experimental research reflect the advantages and disadvantages of the equal-roll and unequal roller straighteners, which is beneficial to make better use of them in operation and to popularize the superior equipment. The theoretical, simulation and experimental analysis method used in this paper is a good attempt for the research of straightening technology in the future. The research on the key technology of straightening has certain theoretical and practical significance.
【学位授予单位】：沈阳建筑大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG333.23

【参考文献】