桥式起重机的疲劳寿命分析与安全性评价方法研究

发布时间：2018-04-16 05:36

本文选题：桥式起重机 + 事故树　；参考：《北京化工大学》2014年硕士论文

【摘要】：随着现代科学技术的快速发展,工业化生产的规模不断朝着大型化、专业化、集成化方向发展。作为现代化生产不可或缺的辅助工具,起重机的需求量越来越大,对其工作以及性能的安全性要求也越来越高。作为一种重要的起重机类型,桥式起重机的主要承重金属结构是主梁,其常见的结构形式是焊接箱型梁结构。主梁包含成百上千条焊缝,常常由于焊接不良等缺陷导致焊缝周围萌生裂纹,疲劳裂纹的扩展就决定主梁的疲劳寿命。因此,根据断裂力学相关理论研究主梁的疲劳裂纹在扩展过程中的规律,并对在役桥式起重机的寿命进行合理估算,对防止桥式起重机失效的发生,指导其设计、制造、使用、检验及管理等有显著意义。针对桥式起重机,本文的主要工作如下： 1、在充分调研桥式起重机的设计标准、使用维护制度、检验检测规范及安全事故等基础上,根据事故树分析法,综合考虑人(人员)、机(起重机)、环(环境)、管(管理)等因素,建立以桥架坍塌为顶事件的事故树。通过定性分析与定量分析,归纳出桥式起重机桥架失效的主要原因,并提出避免事故发生的有效措施。 2、利用ANS YS有限元软件对型号为QL10+10T×16.5m的桥式起重机主梁进行静力学模拟计算,找到了主梁应力较大的危险部位；并以此为母模型,建立三了种疲劳裂纹的子模型,对危险部位的裂纹进行模拟计算,得到了应力强度因子在裂纹扩展过程中的变化规律,进一步计算了裂纹的扩展寿命,绘制出疲劳寿命曲线。 3、为了全面掌握起重机的安全状况,对桥式起重机整机进行安全性评价。本文利用层次分析法进行构权,采取模糊综合评判法对桥式起重机进行安全性评价,得到整机的安全评价值。根据危险等级对起重机制定相应的维修及维护计划,实现完整性管理。
[Abstract]:With the rapid development of modern science and technology, the scale of industrial production continues to develop in the direction of large scale, specialization and integration.As an indispensable auxiliary tool for modern production, the demand for cranes is increasing, and the safety requirements for their work and performance are becoming higher and higher.As an important type of crane, the main load-bearing metal structure of bridge crane is the main beam, and the common structure form is welded box girder structure.The main beam contains hundreds of welds, which often lead to crack initiation around the weld due to defects such as poor welding, and fatigue crack propagation determines the fatigue life of the main beam.Therefore, according to the relevant theory of fracture mechanics, the law of fatigue crack propagation of main girder is studied, and the life of bridge crane in service is estimated reasonably, so as to prevent the failure of bridge crane, guide its design, manufacture and use.Inspection and management have significant significance.The main work of this paper is as follows:1. On the basis of investigating the design standard of bridge crane, using maintenance system, checking and detecting criterion and safety accident, according to accident tree analysis,The accident tree with bridge collapse as its top event is established by taking into account the factors such as human (personnel), machine (crane), ring (environment, management) and so on.Through qualitative analysis and quantitative analysis, the main causes of bridge frame failure of bridge crane are summarized, and effective measures to avoid accidents are put forward.2. By using ANS YS finite element software, the static simulation of the main girder of the bridge crane named QL10 10T 脳 16.5m is carried out, and the dangerous part of the main girder is found out, and the sub-model of three kinds of fatigue crack is established based on the model.The variation of stress intensity factor in the process of crack growth is obtained by simulating and calculating the crack in dangerous position. The crack propagation life is further calculated and the fatigue life curve is drawn.3. In order to grasp the safety condition of crane, the safety evaluation of bridge crane is carried out.In this paper, the analytic hierarchy process (AHP) is used to evaluate the safety of the bridge crane and the fuzzy comprehensive evaluation method is used to evaluate the safety of the crane.Make corresponding maintenance and maintenance plan for crane according to hazard level, realize integrity management.
【学位授予单位】：北京化工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TH215

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