【作者】 刘小文；

【导师】 戴虹；

【作者基本信息】 西南交通大学 ， 材料加工工程， 2006， 硕士

【摘要】 钢轨焊接在无缝线路建设工程中的起着非常重要的作用。随着列车速度与载重的增加,对钢轨焊接质量的要求越来越高。目前,气压焊技术在我国钢轨现场焊接工程中的应用正日益增多,由于钢轨气压焊的焊接温度场对接头质量起着决定性的作用,因而开展钢轨气压焊温度场的研究,对于控制焊接质量,降低焊接成本,提高列车运行安全具有十分重要的意义。 本文采用PLC专用模块和VB编程技术,开发成功了钢轨气压焊工艺参数和温度检测系统,实测了气压焊接工艺参数及其温度变化情况;采用ANSYS有限元分析软件,选择3D单元,对钢轨气压焊温度场进行了模拟计算,通过对钢轨气压焊端面温度场的实测,并对实测结果与模拟结果进行相互比较,改进完善了气压焊温度场有限元模型,得出了模拟计算结果。 结果表明:所开发的钢轨气压焊参数检测系统,能实时检测钢轨气压焊焊接参数,自动生成的气压焊质量管理报表,为追溯钢轨焊接工况、诊断焊轨质量、控制焊轨工程质量提供了现代化管理的有效手段;在青藏线海拔3000m以上的地区,钢轨气压焊的燃烧比应控制在0.96～1.1之间,而在内地低海拔地区(海拔低于1000m),钢轨气压焊的燃烧比一般在0.85～0.95之间:本文建立的三维温度场模型,与实测结果基本吻合,它可为加热器火孔尺寸和结构的优化,以及焊接工艺参数选择提供理论依据。更多还原

【Abstract】 The technology of rail welding plays a very important role in the engineering of laying continuous welded railway (CWR). With the development of high-speed and heavy-loading track, the quality of rail welding is desired to be more and more exigent. Now, the technology of gas pressure welding has been applying in the engineering of rail welding progressively. The temperature field of gas pressure welding plays a crucial role in the quality of welding joint, so the study of welding temperature field is significant to ensure the traffic safety and quality of welding and reduce the cost of welding.In this paper, a detect system of welding parameter and temperature field is developed with Visual Basic(VB) technology;based on the parameter, the temperature field of gas pressure welding of rails is simulated with ANSYS finite element program;the experiment of temperature detecting is done. After comparing the result of simulation and experiment, the finite element model and simulating result is mended.The results show that the parameter detecting system can detect the welding parameter of rail gas pressure welding real-timely and create the quality report automatically, so it provided a useful means to cast back the welding condition and assess the welding quality and control the quality of rail welding engineering;in the Qing Zang railway where altitude is higher then 3000m, the gas proportion of gas pressure welding of rail should be controlled between 0.96~1.1,while the proportion is often between0.85~0.95 in the area where altitude is lower then 1000m;the three-dimensional (3-D) finite element temperature field model in this paper can describe the dynamic temperature distribution of gas pressure welding of rails, which is useful for optimizing the size of welding-flame nozzle and selecting appropriate welding parameters.更多还原