液化气球罐裂纹修复技术研究
发布时间：2018-07-25 15:00
【摘要】：压力容器因为储藏易燃、易爆、有毒、有害的介质而决定了压力容器任何形式的失效都将会给国家和人民的生命财产造成巨大的损失,特别对于液化气球罐裂纹引起的失效已经成为企业界和科技界所关注的重大安全问题,如何有针对性地、可靠与经济地诊断、预测、预防与修复在役压力容器的缺陷已经成为一个值得人们探索和研究的课题。开展球罐质检工作是确定球罐缺陷的一个关键环节,采用表面检查、壁厚测定、无损探伤、硬度测定等手段,可以初步查出球罐的实际安全使用状况,进而分析球罐裂纹的成因,为球罐的缺陷修复寻求切入点。此论文因此开展了大量检验和检测的研究工作,特别是在现场球罐壁厚测定,硬度测定方面为裂纹产生的原因提供了依据。通过壁厚的测定值和设计厚度尺寸对比说明球罐厚度符合要求,球罐硬度的测定值与工艺规定的要求对比说明球罐焊接区硬度偏高,进而推测缺陷产生的主要原因是由于应力导向所致。对裂纹进行了安全性评定,结果显示球罐存在安全性问题,不能继续使用,并用有限元软件对裂纹尖端应力强度因子值进行数值模拟,与解析解对比,可以知道有限元模拟结果的可靠性,也解决一部分复杂裂纹没有准确的解析解情况下可以通过有限元软件求解的问题。并针对球罐的裂纹缺陷研究寻找出合适的补焊工艺,对裂纹进行打磨补焊修复,为了提高球罐的修复后的质量,补焊后再对球罐进行局部热处理,最后对球罐进行气密性试验和水压试验,检验球罐修复后的质量,结果显示修复后的球罐质量可靠,可以安全使用。本文针对在役液化气球罐产生裂纹这一普遍的现象进行了一些探索性的研究工作,提出了一些对在役液化气球罐裂纹修复的基本原则、技术路线和修复方法。根据炼化厂在役液化气球罐因判废而需要修复的实例,依据球罐现场实际组装焊接情况,结合球罐裂纹的检测结果,分析和查找球罐裂纹产生的原因。提出了球罐修复方案和质量保证的措施,提出在保证结构安全的前提下,采用局部热处理方法来达到消氢和降低残余应力的目的,以提高和改善球罐的内在体质,并通过压力试验和水压试验检测,保证球罐的修复质量,使得已经报废的液化气球罐经过修复,恢复了安全使用,也从中探索出修复和防止液化气球罐产生裂纹的较为系统方法。
[Abstract]:Pressure vessels because of storage flammable, explosive, toxic and harmful media determine that any form of failure of pressure vessels will cause great loss of life and property to countries and people. In particular, failure caused by cracks in liquefied petroleum gas spherical tanks has become a major safety issue of concern to the business community and the scientific and technological community. How to diagnose and predict it in a targeted, reliable and economical manner, Prevention and repair of the defects of existing pressure vessels has become a subject worthy of exploration and study. The quality inspection of spherical tanks is a key link in determining the defects of spherical tanks. By means of surface inspection, wall thickness measurement, non-destructive inspection and hardness measurement, the actual safe use of spherical tanks can be preliminarily found out. Then the causes of the spherical tank cracks are analyzed to find a breakthrough point for the defect repair of the spherical tank. Therefore, a lot of research work has been carried out in this paper, especially in the measurement of the wall thickness of spherical tank in the field. The hardness measurement provides the basis for the cause of the crack. By comparing the measured value of wall thickness with the dimension of design thickness, it is shown that the thickness of spherical tank meets the requirements, and the hardness of spherical tank is higher than that of the requirement of technology. The main reason for the defect is the stress orientation. The safety of the crack is evaluated. The results show that the spherical tank is safe and can not be used any longer. The stress intensity factor at the crack tip is numerically simulated by finite element software and compared with the analytical solution. The reliability of finite element simulation results can be obtained, and the problem that some complex cracks can be solved by finite element software without accurate analytical solution can be solved. In order to improve the quality of the spherical tank, the local heat treatment of the spherical tank is carried out. Finally, the air tightness test and water pressure test of the spherical tank are carried out to check the quality of the spherical tank after repair. The results show that the repaired spherical tank is reliable in quality and can be safely used. In this paper, some explorative research work has been carried out in view of the common phenomenon of cracks in LPG spherical tanks in service, and some basic principles, technical routes and repair methods for repairing cracks in LPG spherical tanks in service have been put forward. According to the example that the existing LPG spherical tank in the refinery needs to be repaired because of the judgment of the waste, according to the actual spot assembly and welding of the spherical tank, combined with the detection results of the spherical tank crack, the causes of the spherical tank crack are analyzed and found. The repairing scheme and quality assurance measures of spherical tank are put forward. On the premise of ensuring structural safety, partial heat treatment is used to eliminate hydrogen and reduce residual stress, so as to improve and improve the inner constitution of spherical tank. And through the pressure test and the water pressure test inspection, guarantees the spherical tank repair quality, causes the already abandoned liquefied petroleum gas spherical tank to be repaired, has restored the safe use, A systematic method for repairing and preventing cracks in LPG spherical tanks is also explored.
【学位授予单位】：西安石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE972
本文编号：2144182
[Abstract]:Pressure vessels because of storage flammable, explosive, toxic and harmful media determine that any form of failure of pressure vessels will cause great loss of life and property to countries and people. In particular, failure caused by cracks in liquefied petroleum gas spherical tanks has become a major safety issue of concern to the business community and the scientific and technological community. How to diagnose and predict it in a targeted, reliable and economical manner, Prevention and repair of the defects of existing pressure vessels has become a subject worthy of exploration and study. The quality inspection of spherical tanks is a key link in determining the defects of spherical tanks. By means of surface inspection, wall thickness measurement, non-destructive inspection and hardness measurement, the actual safe use of spherical tanks can be preliminarily found out. Then the causes of the spherical tank cracks are analyzed to find a breakthrough point for the defect repair of the spherical tank. Therefore, a lot of research work has been carried out in this paper, especially in the measurement of the wall thickness of spherical tank in the field. The hardness measurement provides the basis for the cause of the crack. By comparing the measured value of wall thickness with the dimension of design thickness, it is shown that the thickness of spherical tank meets the requirements, and the hardness of spherical tank is higher than that of the requirement of technology. The main reason for the defect is the stress orientation. The safety of the crack is evaluated. The results show that the spherical tank is safe and can not be used any longer. The stress intensity factor at the crack tip is numerically simulated by finite element software and compared with the analytical solution. The reliability of finite element simulation results can be obtained, and the problem that some complex cracks can be solved by finite element software without accurate analytical solution can be solved. In order to improve the quality of the spherical tank, the local heat treatment of the spherical tank is carried out. Finally, the air tightness test and water pressure test of the spherical tank are carried out to check the quality of the spherical tank after repair. The results show that the repaired spherical tank is reliable in quality and can be safely used. In this paper, some explorative research work has been carried out in view of the common phenomenon of cracks in LPG spherical tanks in service, and some basic principles, technical routes and repair methods for repairing cracks in LPG spherical tanks in service have been put forward. According to the example that the existing LPG spherical tank in the refinery needs to be repaired because of the judgment of the waste, according to the actual spot assembly and welding of the spherical tank, combined with the detection results of the spherical tank crack, the causes of the spherical tank crack are analyzed and found. The repairing scheme and quality assurance measures of spherical tank are put forward. On the premise of ensuring structural safety, partial heat treatment is used to eliminate hydrogen and reduce residual stress, so as to improve and improve the inner constitution of spherical tank. And through the pressure test and the water pressure test inspection, guarantees the spherical tank repair quality, causes the already abandoned liquefied petroleum gas spherical tank to be repaired, has restored the safe use, A systematic method for repairing and preventing cracks in LPG spherical tanks is also explored.
【学位授予单位】：西安石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE972
【参考文献】
相关期刊论文 前10条
1 翁东山;;15MnNbR球形储罐裂纹缺陷分析及检验要点[J];质量技术监督研究;2011年01期
2 董大文;07MnCrMoVR钢制2000m~3球罐再热裂纹分析及其修复工艺技术[J];化工设备与管道;2003年06期
3 杨钢;SPV50Q液化石油气球罐裂纹检验与修复[J];化工设备与管道;2005年05期
4 丁中清;史建明;张德喜;;球罐裂纹原因分析及修复[J];石油化工建设;2007年05期
5 李世红;牛全峰;杨学智;田璐;;压力容器用15MnNbR钢及所选焊材的焊接性能研究[J];金属加工(热加工);2011年14期
6 彭国平;李洪刚;;15MnNbR球罐裂纹的分析及修复[J];化工机械;2009年04期
7 陈颖锋;大型球罐再热裂纹的现场修复[J];化工设备与防腐蚀;2004年05期
8 林胜德;液化石油气球罐失效原因分析[J];石油化工设备技术;2000年05期
9 练学余,田庆存;湿硫化氢环境下的球罐腐蚀状况分析[J];石油化工设备技术;2002年03期
10 董双巧;梁清香;王峗;;液化石油气球罐裂纹修复补强研究[J];太原科技大学学报;2013年05期
，本文编号：2144182
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