基于改进GA-BP算法的SMAW工艺参数的优化

发布时间：2018-01-17 13:01

本文关键词：基于改进GA-BP算法的SMAW工艺参数的优化　出处：《内蒙古科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：焊接技术是现代机械制造的关键工艺技术，其中以手工电弧焊最为常见，但容易产生较严重的焊接变形是手工电弧焊最大的缺陷。本文应新宏昌重工有限责任公司技术部的研发需求，针对该公司生产的自卸车车厢焊接变形较为严重的问题，结合公司焊接生产实际，以实用、可行为基本原则，，在深入了解焊接变形形成机理、影响因素和控制技术的基础上，从优化焊接工艺参数的角度出发，采用改进型GA-BP算法来对该公司手工电弧焊焊接工艺进行优化，以期达到解决产品焊接质量缺陷的目的。本文首先对新宏昌重工有限责任公司现有的焊接工艺进行全面分析，客观判断导致焊接变形产生的工艺因素，确定工艺优化方向。在此基础上，针对性的选择基于改进GA-BP算法的焊接变形预测策略和多目标工艺参数优化相结合的策略，来实现对焊接工艺参数的优化。因焊接工艺参数与焊接变形之间的非线性关系高度复杂，本文以焊接电流、焊接电压、焊接速度和冷却速度为输入，以横向收缩变形和角变形为输出，构建了小样本、高精度、基于改进GA-BP算法的变形预测模型，在各项实测数据的基础上，利用该GA-BP模型强大的非线性关系识别能力，来寻找焊接工艺参数与焊接变形之间的非线性关系，奠定多目标工艺参数优化的基础。在多目标工艺参数优化中，以GA-BP变形预测模型所寻找得到的工艺参数与焊接变形之间的非线性关系，来代替多目标工艺参数优化中的目标函数，并结合工厂焊接生产实际情况选定优化变量约束条件、即焊接工艺参数的取值范围，构建基于正交原则的优化求解空间，以横向收缩变形和角变形最小为优化目标，建立多目标工艺参数优化模型，用于实现焊接工艺参数的优化。此外，本文合理设计试验方案，利用真实的实测数据对基于改进GA-BP算法的变形预测模型的预测效率、多目标工艺参数优化模型优化结果的有效性进行了验证，验证表明本文所提出的焊接工艺参数优化策略可以通过实现对焊接工艺参数的优化有效减小焊接变形量。并在此基础上，利用Matlab平台开发出基于改进GA-BP算法的SMAW焊接工艺参数优化系统，大大提升了本文核心理论的的工程应用价值。
[Abstract]:Welding technology is the key technology of modern mechanical manufacturing, in which manual arc welding is the most common. But more serious welding deformation is the biggest defect of manual arc welding. This paper should meet the research and development requirements of the technical department of Xinhongchang heavy Industry Co., Ltd. Aiming at the serious problem of welding deformation of dump truck car produced by the company, combined with the actual welding production of the company, taking practical and feasible as the basic principle, the forming mechanism of welding deformation is deeply understood. On the basis of influencing factors and control technology, from the point of view of optimizing welding process parameters, the improved GA-BP algorithm is adopted to optimize the welding process of manual arc welding in this company. In order to solve the welding quality defects. In this paper, the existing welding process of Xinhongchang heavy Industry Co., Ltd. is analyzed comprehensively, the process factors that lead to welding deformation are judged objectively, and the direction of process optimization is determined. The welding deformation prediction strategy based on the improved GA-BP algorithm and the multi-objective process parameter optimization strategy are selected to optimize the welding process parameters. Because the nonlinear relationship between welding parameters and welding deformation is highly complex, this paper takes welding current, welding voltage, welding speed and cooling speed as input, and takes transverse shrinkage deformation and angular deformation as output. The deformation prediction model based on the improved GA-BP algorithm is constructed with small sample and high precision. Based on the measured data, the strong nonlinear relationship recognition ability of the GA-BP model is utilized. To find the nonlinear relationship between welding process parameters and welding deformation, and lay the foundation of multi-objective process parameters optimization. In the optimization of multi-objective process parameters, the nonlinear relationship between process parameters and welding deformation obtained by GA-BP deformation prediction model is used to replace the objective function in multi-objective process parameter optimization. Combined with the actual situation of factory welding production, the constraints of optimization variables, that is, the range of welding process parameters, are selected, and the optimization solution space based on orthogonal principle is constructed. Aiming at minimum transverse shrinkage and angle deformation, a multi-objective process parameter optimization model is established to optimize welding process parameters. In addition, the experiment scheme is designed reasonably, and the prediction efficiency of the deformation prediction model based on the improved GA-BP algorithm is obtained by using the real measured data. The effectiveness of the optimization results of multi-objective process parameters optimization model is verified. The results show that the proposed optimization strategy can effectively reduce the welding deformation by optimizing the welding parameters. The optimization system of welding parameters for SMAW welding based on improved GA-BP algorithm is developed by using Matlab platform, which greatly enhances the engineering application value of the core theory of this paper.
【学位授予单位】：内蒙古科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG404

【参考文献】