大型概率筛动态特性与焊缝疲劳寿命分析

发布时间：2018-06-22 05:18

本文选题：概率筛 + 模态　；参考：《湘潭大学》2017年硕士论文

【摘要】：概率筛是以物料透筛概率原理来进行筛分作业的一种振动筛。它广泛应用在农业、煤炭、化学、机械和建筑等领域筛分食品、药品及材料等,具有效率高、结构简单等优点,得到广泛应用。其用户数量巨大,所以必须保证概括率领筛的质量。概率筛在日常筛分作业过程中,受到筛分物体撞击力的同时,还受到激振电动机的交变载荷力,这将导致其在使用过程中会出现疲劳开裂的问题。概率筛在制造过程中使用了大量的焊缝连接,焊接工艺的特点决定了焊接接头的疲劳强度一般都低于焊接母材,在实际使用过程中发现,概率筛出现的主要问题是焊缝的疲劳开裂,因此,有必要从焊缝疲劳寿命研究入手来评估概率筛的疲劳寿命。本论文课题来源于湖南省科技计划项目重点研发计划“大型干法楼式砂石绿色生产关键技术研究及装备开发”(项目编号:2015GK3047),以中联重科股份有限公司自主研发的大型概率筛4GLS2530为研究对象,首先对概率筛进行了有限元建模,紧接着分析概率筛的理论模态和应力,为后续疲劳结果分析提供基础;然后通过搭建试验台对概率筛进行模态实验,得到其实验模态结果,将计算和实验模态结果做对比分析;而后在Fe-safe中采用了基于Verity的等效结构应力法对4GLS2530型概率筛相对危险的焊缝进行了疲劳寿命评估,得出了相应的疲劳寿命,并在实验台上进行了空载实验,将理论分析和实验结果进行了对比,二者能较好的吻合,说明了在工程上应用上述方法来评估概率筛焊缝的疲劳寿命是可行的;最后提出了改进概率筛疲劳强度的方法,并对其可行性进行了理论分析。为概率筛在以后的改进中点明了方向,有较好的参考意义。
[Abstract]:The probabilistic sieve is a vibrating screen, which is based on the principle of material screening probability. It is widely used in the fields of agriculture, coal, chemistry, machinery and construction. It has many advantages such as high efficiency, simple structure and so on. Its user quantity is huge, so must guarantee the quality of general lead screen. In the daily screening process, the probability screen is subjected to the impact force of the screening object and the alternating load force of the exciting motor, which will lead to the problem of fatigue cracking in the process of operation. A large number of weld connections are used in the manufacturing process of the probabilistic sieve. The fatigue strength of the welded joints is generally lower than that of the base metal, which is determined by the characteristics of the welding process. The main problem of the probabilistic sieve is the fatigue cracking of the weld seam. Therefore, it is necessary to evaluate the fatigue life of the probabilistic sieve from the study of the fatigue life of the weld. This thesis comes from the key research and development plan of Hunan province science and technology project "key technology research and equipment development of large-scale dry sand and stone green production" (project number: 2015GK3047), which is independently developed by Zhonglian heavy Technology Co., Ltd. Large probability sieve 4GLS2530 is studied. Firstly, the finite element model of the probability sieve is established, then the theoretical modal and stress of the probabilistic sieve are analyzed to provide the foundation for the subsequent fatigue analysis, and then the modal test results of the probabilistic sieve are obtained by setting up a test rig. The calculated and experimental modal results are compared and analyzed, and the fatigue life of the relatively dangerous weld of 4GLS2530 probabilistic screen is evaluated by using the equivalent structural stress method based on Verity in Fe-safe, and the corresponding fatigue life is obtained. The no-load experiment was carried out on the test bench, and the theoretical analysis was compared with the experimental results. The results showed that it was feasible to apply the above method to evaluate the fatigue life of the probabilistic sieve weld in engineering. Finally, the method of improving fatigue strength of probabilistic sieve is put forward, and its feasibility is analyzed theoretically. It points out the direction of the probability screen in the future improvement, and has good reference significance.
【学位授予单位】：湘潭大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TH237.6

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