换热管泄漏断裂失效分析

发布时间：2018-03-22 13:52

本文选题：断裂　切入点：泄漏　出处：《西北大学》2015年硕士论文　论文类型：学位论文

【摘要】：本文从主要单元设备换热器的概况、发展和分类入手,分析了造成换热器中换热管泄漏失效或者断裂失效的原因。作为主要受压元件之一,若换热管由于材质缺陷、严重腐蚀、管束振动等单一的或者几方面的综合原因出现了泄露或者断裂,给现场生产带来的后果是难以估量的。当发生轻微泄漏,可以通过堵管方式来解决,而管子泄漏的根数过多以至于无法满足换热面积的需要时,就只能停车检修甚至重新更换换热器。断裂失效发生的后果更是不可预见。断裂导致了两相流体混流,使两相介质发生不能控制的化学反应。随着时间推移,造成元件的大面积损坏以及压力温度的急剧攀升。由此带来的爆炸、火灾后果都是极其严重的。基于此,笔者根据不同国家的标准规范,对诸多因素中频发事故且造成严重后果的因素进行了定量计算。为了更加符合工程实际的需要,选取了两个实例进行了手工计算和软件电算,得出计算结果后,分析结果的差异以及计算的科学合理性。为了直观的了解断口形貌,从而得出明确的损伤结论,笔者对上述实例中的两个换热管试件进行了实验分析。实验包括了试件基础实验(测厚、测长、测重试验)、采用金相显微镜完成的奥氏体晶粒度测定实验以及扫描电子显微镜断口元素观测和成因判别。综合考虑上述内容,得出了两例中换热管失效的根本原因。经过推测与验证,笔者总结出了换热管失效分析的系统方法,为日后研究此领域的问题提供了一个可供参考的方向,以便做好换热管失效的预防措施,以此保障人员设备安全、减少经济损失、创建节能环保工厂
[Abstract]:Starting with the general situation, development and classification of heat exchangers in main units, this paper analyzes the causes of leakage or fracture failure of heat exchangers in heat exchangers. As one of the main pressurized components, if the heat exchanger tubes are seriously corroded due to material defects, The leakage or fracture of a single or several factors, such as tube bundle vibration, has resulted in incalculable consequences for on-site production. When there is a slight leakage, it can be solved by plugging the pipe. However, if the pipe leakage has too many roots to meet the need of heat transfer area, it can only stop to repair or even replace the heat exchanger. The consequences of the fracture failure are even more unpredictable. The fracture leads to the mixed flow of two-phase fluid. Causes uncontrolled chemical reactions in the two-phase medium. Over time, it causes extensive damage to the components and a sharp rise in pressure and temperature. The resulting explosion and fire consequences are extremely serious. According to the standards and specifications of different countries, the author calculates quantitatively the factors which occur frequently in many factors and cause serious consequences. In order to meet the needs of engineering practice, two examples are selected to carry out manual calculation and software computer calculation. After getting the result of calculation, the difference of the result and the scientific rationality of calculation are analyzed. In order to understand the fracture morphology intuitively and draw a clear conclusion of damage, The author has carried on the experimental analysis to the two heat transfer tube specimens in the above examples. The experiment includes the basic experiment of the specimen (measuring thickness, measuring length, measuring the thickness, measuring the length, measuring the thickness, measuring the length), The gravimetric test, the measurement of austenitic grain size by metallographic microscope, the observation of the fracture surface elements and the cause of formation of the scanning electron microscope (SEM) were carried out, and the above contents were considered synthetically. The fundamental causes of the failure of heat exchanger pipe in two examples are obtained. After speculation and verification, the author summarizes the systematic method of failure analysis of heat exchanger pipe, which provides a reference direction for the future study of the problems in this field. In order to do a good job of heat exchange pipe failure prevention measures, so as to ensure the safety of personnel and equipment, reduce economic losses, and create energy conservation and environmental protection factories
【学位授予单位】：西北大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ051.5

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