【作者】 李静；

【导师】 陈世利；

【作者基本信息】 天津大学 ， 精密仪器及机械， 2009， 硕士

【摘要】 在液体和气体的输送方面,管道运输有其不可取代的突出优势,在世界范围内得到了广泛应用。影响埋地管道可靠性和使用寿命的关键因素是管道金属的腐蚀。为了防止管道腐蚀,普遍采用防腐涂层和电化学方法进行保护。而防腐涂层会因多种因素产生缺陷,失去防腐效果,导致管道被腐蚀,甚至发生管道泄漏等恶性事故。根据国内外经验,我国大多长距离油气管道已逐步进入事故高发期。因此,有计划地开展管道防腐层的修复工作已刻不容缓。为了对管道防腐层修复决策提供科学依据,研究管道防腐层缺陷检测及其评价方法,精确高效地测定管道的防腐层状况具有重要意义。本文对防腐层缺陷检测技术进行了深入研究,主要进行了以下几个方面的工作:1.埋地管道涂层质量检测方法多种多样,深入研究了各种方法的优缺点,并最终提出了能同时检测破损和剥离缺陷的基于电化学阻抗谱技术的检测方法。2.分析了埋地管道体系的等效电路模型,为将电化学理论应用于管道涂层缺陷检测打下了坚实基础。3.采用小幅度正弦恒电流激励的涂层缺陷检测方法,研制了一套防腐层缺陷检测实验装置,利用研制的实验装置对防腐层破损和剥离试片进行测试,获得了大量数据,实验结果与实际情况吻合良好。证明了该方法可应用于防腐层缺陷检测。4.研制了用于现场检测防腐层缺陷类型的仪器。更多还原

【Abstract】 In terms of transporting liquid and gas, the method of pipeline transportation has prominent advantage and has been widely used all over the world. The external corrosion of steel becomes one of the most important problems of influencing the reliability and the lifetime of buried pipeline system. To avoid the corrosion, antiseptic coating and electrochemistry method are usually used. The antiseptic coating will lose its effects due to several factors, and cause the pipeline corrosion, even result in the pipeline leakage. According to the experience, most of the long distance oil or gas pipelines in our country have been gradually stepped into a period of high possibility of events. So it is necessary to carry on the work of repairing the antiseptic coating of pipelines in time. In order to provide the scientific basis of this work, it has great significance to research the method of measurement and evaluation to the defects of pipeline antiseptic coating, as well as evaluate the quality of the coating accurately and effectively. The technique of antiseptic coating detection has been studied intensively in this dissertation, and the main work accomplished can be summed up as the following aspects.1. There are many methods to detect the quality of the buried pipeline coating, and the advantages and disadvantages of these methods are studied intensively. Electrochemistry method which can detect faults of coating and disbond at the same time is proposed.2. Analyse equivalent circuit model corresponding to buried pipeline system, which laid firm foundations of electrochemistry theory application to the detection of pipeline coating faults.3. A coating defect detection method which uses small amplitude lasting sine, whose feasibility is testified during practical process. A set of experimental apparatus controlled by MCU is developed to detect coating defaults. Both the conditions of coating defect and disbond of sample plates are tested with the experiment apparatus. The results acquired from the experiment and the current conditions are accorded well with each other, which indicated that it is feasible to distinguish coating defaults with this method.4. A set of detection instrument is developed to judge the type of the antiseptic coating defects on real field.更多还原