Cryogenic Tanks Recertification: Case Study for Operational-Life Extension

A. Adamou
{"title":"Cryogenic Tanks Recertification: Case Study for Operational-Life Extension","authors":"A. Adamou","doi":"10.2118/171998-PA","DOIUrl":null,"url":null,"abstract":"phased structure still has ferrite, but the resulting alloy is ductile enough for static structures such as storage tanks. LNG-storage-tank iron/nickel alloys (9%-nickel alloys are most commonly used), with piping and similar attachments made from austenite stainless steel, have better resistance to thermal fatigue. Corrosion is not a problem at cryogenic temperature, so galvanic coupling between nickel steel and stainless steel is not a source of problems. Austenitic stainless steels at LNG temperatures may be used for building smaller storage tanks, but large containment vessels are usually welded from 9%-nickel steel because of expense considerations. This practice is well-established worldwide (Mokhatab et al. 2014). 3.5%-nickel steel was introduced into cryogenic applications in 1944 for construction of an LNG tank; stainless-steel alloys were scarce because of shortages resulting from World War II. Shortly after going into service, on 20 October 1944, the tank failed. In 1946, investigations by the US Bureau of Mines concluded that the incident was a result of the low-temperature embrittlement of the inner shell of the cylindrical tank. The 3.5%-nickel steel was not used further for cryogenic applications (Mannan 2005). Since 1985, ADGAS has been operating three 80 000-m3, aboveground, double-containment-type tanks, designed according to API Standard 620 (2013), that consist of an inner tank and an outer tank. The inner tank is made of 9%-nickel steel. The outer tank has a post-tensioned concrete wall with a reinforced concrete roof. A secondary bottom is connected to the outer-tank wall to provide a flexible liquid seal. The entire construction is made of 9%-nickel steel. Between 2012 and 2013, a longevity study of the storage and export areas was conducted to ensure their fitness for service up to 2019, as a base case, and 2045, as an extended case. Recertification of “conventional” static equipment, piping, jetty, electrical components, instrumentation, rotating elements, structure, and concrete foundations are not addressed in this paper—only LNG tanks are covered. These tanks have never been inspected internally. The most-important outcome from this study is to advise whether to keep them running beyond their design life or to conduct an intrusive inspection to verify their condition. In this paper, the focus will be given first to the 9%-nickel steel, its properties, and its use in LNG-storage tanks. The different LNGtank design generations and their particularities will be described. A general overview of LNG-tank failures, as recorded in the industry, is presented. Finally, the approach adopted by ADGAS to recertify the LNG tanks is explained. Basically, it is a matter of whether to conduct an intrusive inspection or to keep the tanks operating on the basis of industry practice. For this, well-documented cases will be presented, mainly from Ishikawajima-Harima Heavy Industries, Brunei LNG, Gaz de France, and Malaysia LNG.","PeriodicalId":19446,"journal":{"name":"Oil and gas facilities","volume":"73 1","pages":"88-100"},"PeriodicalIF":0.0000,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Oil and gas facilities","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.2118/171998-PA","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 1

Abstract

phased structure still has ferrite, but the resulting alloy is ductile enough for static structures such as storage tanks. LNG-storage-tank iron/nickel alloys (9%-nickel alloys are most commonly used), with piping and similar attachments made from austenite stainless steel, have better resistance to thermal fatigue. Corrosion is not a problem at cryogenic temperature, so galvanic coupling between nickel steel and stainless steel is not a source of problems. Austenitic stainless steels at LNG temperatures may be used for building smaller storage tanks, but large containment vessels are usually welded from 9%-nickel steel because of expense considerations. This practice is well-established worldwide (Mokhatab et al. 2014). 3.5%-nickel steel was introduced into cryogenic applications in 1944 for construction of an LNG tank; stainless-steel alloys were scarce because of shortages resulting from World War II. Shortly after going into service, on 20 October 1944, the tank failed. In 1946, investigations by the US Bureau of Mines concluded that the incident was a result of the low-temperature embrittlement of the inner shell of the cylindrical tank. The 3.5%-nickel steel was not used further for cryogenic applications (Mannan 2005). Since 1985, ADGAS has been operating three 80 000-m3, aboveground, double-containment-type tanks, designed according to API Standard 620 (2013), that consist of an inner tank and an outer tank. The inner tank is made of 9%-nickel steel. The outer tank has a post-tensioned concrete wall with a reinforced concrete roof. A secondary bottom is connected to the outer-tank wall to provide a flexible liquid seal. The entire construction is made of 9%-nickel steel. Between 2012 and 2013, a longevity study of the storage and export areas was conducted to ensure their fitness for service up to 2019, as a base case, and 2045, as an extended case. Recertification of “conventional” static equipment, piping, jetty, electrical components, instrumentation, rotating elements, structure, and concrete foundations are not addressed in this paper—only LNG tanks are covered. These tanks have never been inspected internally. The most-important outcome from this study is to advise whether to keep them running beyond their design life or to conduct an intrusive inspection to verify their condition. In this paper, the focus will be given first to the 9%-nickel steel, its properties, and its use in LNG-storage tanks. The different LNGtank design generations and their particularities will be described. A general overview of LNG-tank failures, as recorded in the industry, is presented. Finally, the approach adopted by ADGAS to recertify the LNG tanks is explained. Basically, it is a matter of whether to conduct an intrusive inspection or to keep the tanks operating on the basis of industry practice. For this, well-documented cases will be presented, mainly from Ishikawajima-Harima Heavy Industries, Brunei LNG, Gaz de France, and Malaysia LNG.
低温储罐重新认证:延长使用寿命的案例研究
相相结构仍然有铁素体,但所得到的合金具有足够的延展性,可以用于诸如储罐之类的静态结构。lng储罐铁/镍合金(最常用的是9%-镍合金),管道和类似的附件由奥氏体不锈钢制成,具有更好的抗热疲劳性能。在低温下腐蚀不是问题,所以镍钢和不锈钢之间的电偶并不是问题的根源。液化天然气温度下的奥氏体不锈钢可用于建造较小的储罐,但出于费用考虑,大型容器通常由含9%镍的钢焊接而成。这种做法在世界范围内都是公认的(Mokhatab et al. 2014)。1944年,3.5%镍钢被引入低温应用,用于建造LNG储罐;由于第二次世界大战造成的短缺,不锈钢合金非常稀缺。1944年10月20日,在投入使用后不久,坦克发生了故障。1946年,美国矿业局的调查得出结论,该事件是由于圆柱形储罐的内壳在低温下脆化造成的。含3.5%镍的钢没有进一步用于低温应用(Mannan 2005)。自1985年以来,ADGAS一直在运营3个80000 -m3的地上双密封罐,根据API标准620(2013)设计,由一个内罐和一个外罐组成。内罐由含9%镍的钢制成。外罐具有后张混凝土墙和钢筋混凝土屋顶。第二底连接到罐外壁,提供灵活的液体密封。整个建筑由含镍9%的钢制成。在2012年至2013年期间,对储存区和出口区进行了寿命研究,以确保它们在2019年(基本情况)和2045年(扩展情况)之前都能正常使用。“传统”静态设备、管道、码头、电气元件、仪表、旋转元件、结构和混凝土基础的重新认证在本文中没有涉及,只涉及LNG储罐。这些储罐从未进行过内部检查。这项研究最重要的结果是建议是否让它们超过其设计寿命或进行侵入性检查以验证其状况。在本文中,重点将首先给出9%镍钢,它的性能,以及它在液化天然气储罐中的应用。不同的长坦克设计世代和他们的特点将被描述。概述了液化天然气储罐故障,在行业中记录,提出。最后,介绍了ADGAS对LNG储罐进行再认证的方法。基本上,这是一个是否进行侵入式检查或根据行业惯例保持储罐运行的问题。为此,将介绍有充分记录的案例,主要来自石川岛harima重工、文莱液化天然气、法国天然气公司和马来西亚液化天然气公司。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
自引率
0.00%
发文量
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信