【作者】 袁帅；

【导师】 韩旭； 翟兴学；

【作者基本信息】 湖南大学 ， 车辆工程， 2013， 硕士

【摘要】 大型焊接件存在焊接残余应力是不可避免的，焊接残余应力的存在严重的影响了焊接件结构的使用性能。因此，研究焊接件残余应力的检测和消除是至关重要的。本文主要目的是对某企业生产的DN1200型阀门蝶板焊接残余应力的检测和消除方法进行研究。通过振动时效与热时效两种工艺对焊缝残余应力的消除效果分析，制定符合国家标准的先进工艺。对阀门蝶板进行实验模态分析，为振动时效工艺的效果提供理论基础。本文对焊接件残余应力产生的原因、残余应力的分类以及残余应力的危害进行详细阐述，得出消除焊接残余应力的必要性。从而列举出焊接件在焊接当中和焊接后消除残余应力的方法，并分析各方法可行性与消除效果。在分析各种方法的消除效果上，根据对材料的破坏性与非破坏性分类提出多种检测残余应力的方法。本文依据实验需要与研究对象的匹配，对阀门蝶板选取振动时效与热时效工艺进行焊接残余应力消除，并利用盲孔法对残余应力进行检测。通过美国NI公司的动态应变数据采集系统分别对两块相同的阀门蝶板进行振动时效和热时效前后的应变数据采集，并利用Matlab软件对应变数据进行离线分析。实验结果表明，使用振动时效工艺消除残余应力的消除率比热时效工艺进行应力消除明显。在对蝶板进行实验模态分析后，得到蝶板的实验模态频率与振动时效系统自动检测出的第一阶频率非常接近。通过一系列的研究和实验证明，本文建立了可行的消除焊接残余应力的工艺，为大型焊接件进行焊接残余应力的消除提供了理论基础和实验指导，促进了振动时效工艺在大型焊接件去除残余应力中的应用。更多还原

【Abstract】 The welding residual stress exists in big welding structure inevitably, andseriously influences the mechanical property of structure. Therefore, accurateeliminate and measurement of residual stress is very important. The main purpose ofthis paper is to study the methods of testing and analy zing the Main Inlet Valve No.1which product by one company. Through the analysis of the effect of Vibratory StressRelief (VSR) and Thermal Stress Relief (TSR) to eliminate residual stress developedan advanced technology in line with national standards, then provided a theoreticalbasis for the VSR through the experiment modal analysis of the valve.The paper described the existence reason of residual stress, residual stressclassification, and residual stress harm. To eliminate the welding residual stress isnecessary. It listed some methods of eliminating residual stress, and analyzed theeffect of all the methods, and based on the destruction and non destruction of thematerial proposed a variety of methods of testing residual stress. According the needof experiment and research object, used VSR and TSR to eliminate residual stress andtest residual stress by blind-hole method.The paper did a strain date collecting by the data acquisition system product byNI Company, and then analyzed the offline date by Matlab software. T he experimentalresults showed that the residual stress elimination rate by used VSR were higher thanTSR. After the experimental modal analysis of the valve, we got the first modalfrequencies, well very close to the frequency of VSR. Through the research andpractical verification, the paper establishes a feasible to eliminate welding residualstress of large welding parts, promoting the theoretic analysis of residual stress andinstruction, promoting the application of VSR on large welding product analysis andengineering.更多还原