Development and application of Baosteel X80 large diameter UOE longitudinal submerged arc welded pipes

With the increase in energy demand,the demand for oil and gas transmission pipes,particularly high-grade longitudinal submerged arc welded pipes (LSAWs),have been growing in recent years.The construction of the 2nd West-East natural gas transmission pipeline project shows that the oil and gas pipeline construction has entered a new phase of development with X80 pipes being applied in large scales for the first time in China.This paper briefly introduces the 2nd West-East natural gas transmission pipeline project and its main technical requirements with the focus on the features of API standard 5L X80 grade  1219 mm series of U-ing-O-ing-Expanding (UOE) LSAW pipes,which Baosteel developed with the integrated technology for the 2nd West-East natural gas transmission pipeline project.The analysis shows the extra-low carbon content,the high contents of manganese and niobium,the fine microstructure,the high strength,the toughness and the good weldability of X80 pipes meet the requirements of "the technical specification of LSAW linepipes for the 2nd West-East natural gas transmission pipeline project in China".By the end of June 2010,Baosteel had totally produced 322000 t of  1219 mm X80 UOE steel pipes,which have been successfully used in the 2nd West-East natural gas transmission pipeline project,thus filling the gap of the production of large diameter X80 UOE LSAW pipes in China.     

天然气输送管件三通用X90钢板的开发

在中石油计划建设西气东输三线X90/X100管线钢试验段背景下,舞钢成功开发天然气输送管件三通用X90钢板,钢板由中油管道局机械制造厂制作成三通并经西安管材所检验,各项性能指标均符合X90管线钢三通的要求。     

高强度管线钢的开发

通过管线长距离运输天然气、石油是能源运输的主要方式。出于降低成本的需要,天然气运输管线的工作压力不断提高,这就要求应用X80或更高级别的管线钢。本文主要从成分设计、工艺设计以及性能分析等方面,论述了Φ1016mm×22.0mm管线用X80热轧钢板的研制。     

太钢2250mm热连轧X80管线钢的生产实践

本文论述了太钢2250mm热连轧开发西气东输二线工程用X80管线钢过程中的主要技术难点、工艺 技术改进、质量改善工作;经过努力大大提升了主要性能指标、一次检验性能合格率及实物质量;满足了 用户的使用要求,太钢X80管线钢产品综合指标达到了国际一流水平。     

Research status of corrosion environment failure and safety assessment of pipeline welded joint

Pipeline transportation is an economical,safe,and efficient transportation method for transporting oil,natural gas,mineral slurry,and other fluids.Welding is the most critical construction process in pipeline engineering and is crucial in the safe operation and service of an entire pipeline system.Theoretically,the girth welded joint is the weakest link in a pipeline system.The unevenness of the structure and performance of the joint caused by welding frequently results in the failure of the welded joint before the failure of the base material of the pipe body,causing the pipeline to leak or even break.For steel pipes used in an acidic corrosive medium environment,the integration of the corrosive medium and mechanical load will accelerate the failure of the welded joint.This article reviews the failure modes of pipeline welded joints in acidic corrosive media,including stress corrosion cracking,hydrogen-induced cracking,and corrosion fracture,and corrosion fatigue considering the diffusion and accumulation of H+at the crack tip.It also reviews service pipelines in acidic corrosive media.The general processing technology of pipe joint engineering critical assessment(ECA)is investigated to provide a reference for the future development of technology in this field.     

宝钢管线钢炼钢生产技术进步

宝钢自20世纪90年代初开始批量生产管线钢以来,已经生产了API-X42～X80、抗硫化氢X52～X65等钢级管线钢合计超过400万t,并于2006年成功试制了X100和X120厚板管线钢。管线钢板卷已经用于塔里木盆地输油管线、苏丹管线、西气东输管线、中俄管线等国内外输油、输气重点工程。在十多年的生产中,炼钢通过改进装备、集成一贯工艺技术以及现场操作管理技术的进步,在管线钢的纯净度控制、铸坯成分均一化控制以及表面缺陷改善等方面取得明显进步,实物[P]达到50×10^-4％,[S]达到12×10^-4％。     

X80级SSAW钢管的产业化开发

介绍了我国SSAW油气输送管线的产能现状以及开发高钢级钢管的意义。以Q/SY GJX0102-2007《西气东输二线管道工程用螺旋缝埋弧焊管技术条件》及API Spec 5L:2004《管线管规范》技术规范为目标,浙江金洲管道工业有限公司通过对现有产品大纲为X70的生产线设备进行升级改造,优化制管生产工艺,于2009年成功开发了高强、高韧性的X80钢级SSAW钢管。介绍了X80钢级SSAW铜管的研制和产业化开发过程,研究结果表明,研发的钢管产品各种性能指标完全符合Q/SY GJX0102-2007《西气东输二线管道工程用螺旋缝埋弧焊管技术条件》标准规定要求,并要优于美国API5L标准。     

高等级管线钢的发展现状

回顾总结了近年来国际上高等级管线钢的发展.现代管线钢向高强度、大厚度、抗应变和抗HIC方向发展.为降低长距离天然气管线的建设成本,开发了X100和X120超高强度管线管,并进行了X100和X120管线试验段建设,取得了显著的进展.开发了以双相显微组织为特征的满足"基于应变设计"的抗大应变高强度管线钢,强度等级从X65至X100,可应用于冻土带、地震区和水土流失区域的管线建设.海底管线用钢和抗HIC管线管的强度等级已从以往的X65提高到X70,X70管线管的最大壁厚可达34.1 mm,并已批量在工程中应用.新型的HTP高强度管线钢采用超低碳高铌含铬的成分设计,具有十分优良的性能,用铬替代钼可显著地降低成本,生产的X80管线管已应用于美国第一条X80管线.     

Arc welding of annular seams under flux in high-strength X80 steel pipe

The relation between the content of martensitic-austenitic phase and the final temperature in accelerated cooling is investigated, in terms of the attainment of high deformability without failure. The ratio of the yield point to the strength (Y/T) in the longitudinal direction (L) of X80 steel pipe produced by UOE technology is found to be between 0.74–0.79. This indicates good deformability of the pipe. A welding technology has been developed such that the metal in the seam matches the strength of the X80 steel pipe. In industrial flexure tests, when the internal pressure is 72% of the standard yield point (SMYS) of X80 steel, the failure of X80 steel pipe welded by the given technology occurs in the basic metal, far from the annular weld.     

X80管线钢在长输管道中的应用及展望

随着长输管道输送压力的提高和对输送效率的要求,X80管线钢在天然气长输管道中的使用逐渐规模化。化学成分作为钢材的“基因”,分析其演变过程并确定合适的目标成分是解决制造、焊接等问题的关键。煤制气输送管道目前没有X80管线钢的工程应用,为了满足中石化在建新疆煤制气外输管道工程的需求,需要加强煤制气管道用X80管线钢的研究。     

宝钢管线钢的发展回顾

文章回顾了过去15年间宝钢管线钢的发展.通过对高强度高韧性管线钢、具有抗HIC性能管线钢和大口径输气管线用厚规格的针状铁素体型X70管线钢的研究开发,形成宝钢X系列管线钢的成分和工艺体系.产品质量稳定,已批量应用于西气东输管线工程、忠武输气管线工程、土耳其输气管线工程等国内外重要管线工程.     

高级别厚规格X80管线钢研制开发

介绍了采用低碳成分设计和TMCP工艺开发X80钢级石油输送管用热轧卷板的关键控制技术和工艺路线。通过低碳多合金强化等微合金化的成分设计、控制钢水的纯净度和板坯的偏析,采用合理的两阶段控制轧制及控制冷却工艺,可以得到针状铁素体＋贝氏体组织。检测指标表明：强度指标和低温韧性等各项力学性能良好,满足中石油＂西二线＂管道工程用热轧卷板技术条件,制管后管体取样各项指标良好。     

具有优异低温韧性的API X80级别电阻焊接管线钢

介绍X80电阻焊接(ERW)管线钢的本质和特点。厚壁高强管线钢将越来越多地用于高压管线,以提高天然气和石油的输送效率,为了提高X80热轧板卷的材料性能,研究了显微组织、化学成分对强度和韧性的影响。基于此结果,采用热机械控轧工艺(TMCP)技术开发了具有细小析出物和非粗大珠光体或马氏体的超低碳贝氏体铁素体钢,获得了低温用途基材和焊缝性能的良好平衡。     

高强管线钢管自动环焊技术现状及宝钢研究进展

介绍当前油气输送管道及其环缝焊接技术发展概况,综述了X80高强管线钢管的开发应用及环缝焊接技术。管道工程建设的发展对自动环缝焊接技术提出了新的需求,其将成为今后管道环缝焊接领域的发展趋势,阐述了当前存在的各种自动环缝焊接方法。宝钢在开展管道环缝手工焊接与半自动焊接的基础上,将开展管道自动焊接技术研究,为用户提供技术支撑。     

高级别管线钢X80～X120的研发与应用

通过管线长距离运输天然气、石油是能源运输的主要方式之一。出于降低成本的需要，天然气输送管线的工作压力不断提高，这就要求应用X80-X120更高级别管线钢。根据有关的文献资料，系统整理并介绍了高级别管线钢的性能指标、成分设计以及生产应用中的热点问题，并讨论了未来中国天然气管线所采用高级别钢的可能选择。     

海底管线管X56 PSL2的研制

 从化学成分设计、冶炼连铸工艺、热轧工艺等方面对海底管线管X56 PSL2进行了研究,并且在衡管进行了海底管线管X56 PSL2的工业试制,满足了油田用户对海底管线管X56 PSL2的需求。实践证明,衡管的工艺方案,满足和适应了油田用户的需要。海底管线管X56 PSL2的研制成功,为衡管生产低碳微合金化高强度管线提供了生产经验,并具有指导作用。     

Girth weldability and welding process of Baosteel X80 UOE linepipes

An analysis of the girth weldability of Baosteel X80 UOE (U-ing-O-ing-Expanding) linepipes was conducted using manual shielded metal arc welding (SMAW) and semiautomatic self-shielded flux cored wire arc welding (FCAW).A technical specification for the optimum quality of a girth welding joint was obtained through a large amount of testing.According to the requirements of America Petroleum Institute(API) standard 1104 and the standards of the 2nd West-East natural gas transmission pipeline project,the mechanical properties of a girth welding joint were estimated.In addition,the effect of the girth welding procedure specifications and the consumable’s suitability on the impact toughness of the girth welding joint was discussed.     

高韧性X65管线钢板的开发与生产

介绍了济钢中厚板厂供泰国某管道工程X65管线钢开发生产情况,采用低碳Mn Nb Mo Ti的合金系针状铁素体钢成分设计,配合洁净钢冶炼以及合理的板坯加热、轧制冷却工艺,生产出的X65管线钢板具有较高的强度,良好的低温韧性以及止裂性能。     

Failure of large-diameter steel pipe with rolling scabs

Russian pipelines employ large-diameter pipe of straight-seam, two-seam, and spiral-seam type (diameter up to 1420 mm, API strength class up to K65). The newest developments in the production of large-diameter (1020, 1220, and 1420 mm) straight-seam welded pipe (strength classes K38–K65 and X42–X80, wall thickness up to 52 mm, length up to 18 mm, and working pressure up to 22.15 MPa) is stepwise press shaping (the JCOE process), proposed by SMS Meer (Germany). The SMS Meer technology is widely used at Russian pipe plants (AO Vyksunskii Metallurgicheskii Zavod, AO Izhorskii Trubnyi Zavod, PAO Chelyabinskii Truboprokatnyi Zavod) and also plants in Russia, China, and India. However, the accident statistics for Russian pipelines show that stress corrosion of the pipe wall mainly occurs in pipelines of large diameter (700–1420 mm). More than 80% of pipeline failures associated with stress corrosion occur in pipelines of diameter 1020–1420 mm. Corrosion cracking of pipe walls may be attributed to three main factors: (1) poor steel quality and pipe defects in manufacturing (such as high residual stress, microcracks and micropeeling of the metal after shaping of the pipe blank, corrugation, scratches, scabs from the rolling process, and imperfections of the weld seams); (2) the presence of a corrosive medium and its access to the metal surface; (3) multicyclic fatigue and failure of the metal on account of pulsation of the working pressure within the pipe and hydraulic shocks. In Russian oil pipelines, failures due to production defects and assembly and installation problems are twice as frequent as in the United States and Europe. Therefore, careful study of pipeline failure due to production flaws is of great importance. In the present work, a mathematical approach is proposed to determining the critical pressure in the pipe at which elastoplastic failure of the pipe will occur at rolling scabs accompanied by a scratch on the pipe’s outer surface. The results may be used in failure diagnostics of large-and medium-diameter steel pipe for major delivery pipelines and transfer pipelines.     

X100管线钢开发实践

根据高强度管线钢发展趋势,参考API SPEC 5L-2007《管线钢管规范》和中国石油天然气集团公司《天然气输送管道X100钢级螺旋缝埋弧焊管用热轧板卷技术条件》要求,邯钢公司制定了X100管线钢热轧卷板生产试制的技术要求。通过化学成分、冶炼、控轧控冷工艺设计,邯钢公司试制生产的X100管线钢在2250热连轧生产线热轧卷板具有较高的强度和良好的低温韧性,金相组织检验为"板条贝氏体+粒状贝氏体"组织,产品的各项力学性能达到了设计要求。