【作者】 陈小龙；

【导师】 赵章焰； 唐智奋；

【作者基本信息】 武汉理工大学 ， 机械电子工程， 2008， 硕士

【摘要】 门座起重机,在国民经济许多部门得到了广泛的应用。由于其工作环境恶劣,载荷复杂,致使其主要受力构件常出现意想不到的开裂,造成巨大的经济损失和人员伤亡事件。在对多起门座起重机金属结构事故事后分析中,可以看到:裂纹总是在事故发生之前就产生了,并且随着时间的推移,裂纹不断扩展。当裂纹扩展到一定程度,便使得金属结构发生致命性的破坏。而伴随金属结构故障的发生,我们总是可以看到疲劳破坏在这一过程中的重大影响。金属结构的疲劳与裂纹之间是否存在着一定程度的对应关系呢?本文以门座起重机金属结构为研究对象,对此问题加以探讨。本文运用参数化技术对门座起重机的运行过程加以参数化建模,并对整机结构进行疲劳分析;利用Visual C++软件绘制整机的疲劳云图,并将疲劳计算结果与裂纹的调查统计数据加以比较,找出它们之间存在的关系。具体工作如下:1)用ANSYS的内部命令和APDL语言建立门座起重机金属结构有限元模型,这是最为基础也是至关重要的一个环节;2)分析结构的强度,以确定裂纹的产生以及构件的断裂并不是由于结构的强度不够而产生的;3)确定疲劳载荷以及疲劳分析方法;4)分析门座起重机结构的疲劳计算结果。以计算出来的疲劳数据为基础,绘制疲劳云图;将疲劳计算结果与裂纹的调查统计数据加以比较,找出它们之间存在的关系;5)在以上基础上,提出提高金属结构疲劳强度的建议和方法,防止结构过快疲劳,延缓裂纹的扩展速度,从而延长门座起重机的使用寿命。更多还原

【Abstract】 The portal crane is widely used in many departments of national economy. But the abominable working environment and complex loads cause the mainly load-carrying components of the structure often occured fracture unexpected. And these accidents lead to the enormous economic loss and casualty incident.By analyzing a lot of metal structure accidents of portal crane, we can see: The crackle has been always produced before accident taking place, and the crackle is expanding constantly as time goes on. When the crackle expanding to a certain degree, it make metal structure take place fateful destroy. Accompany by the trouble of metal structure emergence we always can see the great influence of fatigue in this course. Is there corresponding relationship of a certain degree between the fatigue and crackle of metal structure? This text takes the metal structure of portal crane as an example to discuss this question.This text uses parameterized technology to modeling the operating process of the portal crane, and analysis the fatigue of whole structure; Draw the fatigue nephogram of the crane by using Visual C++ software, and compare the result of fatigue calculation with the investigation statistics of the crackle, find out the relationship between them. The main research contents and results of the dissertation are as fellows:1) To build a portal crane’s FEM model by using ANSYS internal command—APDL. This is the most basic and important step of the text;2) Analysis the strength of structure;3) Confirm the loads and method of fatigue calculation;4) Study the fatigue calculation result of the crane structure. Draw the fatigue nephogram of the crane basic on the datum by calculating out; Compare the fatigue calculation result with the investigate date of the crackle, find out the relationship between them;5) Propose some suggestions and methods on the basis of the above, delay the speed of fatigue and the speed of the crackle expansion, extend the service life of the portal crane.更多还原