支吊架零部件重量及吊零方式对弹簧选型和管道应力分析的影响

本文通过大量的计算,分析了支吊架零部件重量及吊零方式对管道位移、载荷、应力、模态频率和弹簧型号的影响。结果表明,冷态吊零比热态吊零具有更小的OPE运行应力和SUS持续应力;一次应力计算获得的弹簧载荷整定值约比准确值低6％;使用两次应力计算可获得精确的弹簧整定值;一次计算加上支吊架零部件重量再重新计算弹簧也能获得比较准确的整定值。     

某燃气轮机电厂余热锅炉再热器1出口集箱异常位移原因分析及对策研究

本文叙述了某燃气轮机发电厂1号机组余热锅炉再热器1出口至再热器2进口集箱支吊架的运行时状态和存在的问题,支吊架调整前,再热器1出口集箱垂直方向热位移异常,集箱一端向下热位移不足,另一端反向向上翘曲。支吊架在状态检查以及其应力校验、核算的基础上,通过综合性的研究分析提出了该管道支吊架的调整方案并且依据方案对再热器1出口集箱载荷设计偏大的2组支吊架进行了更换。热态复核检验结果为支吊架承载应力及热位移量正常,管道热位移量正常,管系应力合格,达到了整治目标。     

蒸汽管道应力分析和支吊架调整

对某火力发电厂蒸汽管道进行了位移测量和应力计算,并依据计算结果对管道进行了支吊架的调整,结果表明支吊架的调整解决了管道运行存在的问题.     

新建火电机组调试过程中管道支吊架的安全性分析

本文介绍了管道支吊架的类型及其失效对电厂管道系统安全运行的影响，重点分析了在新建机组的调试过程中容易引起管道支吊架失效的原因，并提出了预防支吊架失效的措施及建议。     

1000MW火电机组热再热管道设计

研究和分析1000MW火电机组热再热管道的柔性设计、支吊架设置和应力计算。并通过CAESARII软件对某电厂的热再热管道进行应力分析实践。目前该工程已投产,管道运行良好。     

300 MW机组汽水管道支吊架调整及管系应力分析

本文浅述了沙角发电总厂A5机组汽水管道支吊架的运行现状和存在的问题 ,进行了四大管道管系应力校核计算分析及恒力弹簧吊架的载荷性能测试。在综合分析的基础上提出了支吊架调整方案 ,并进行了工程实施。     

某1000MW超超临界机组高温再热蒸汽管道异常膨胀原因探讨

某1 000 MW超超临界机组管道支吊架检查过程中发现高温再热蒸汽管道膨胀异常,该管道大量恒力吊架指示异常,部分恒力吊架冷态和热态均处于下极限位置,严重阻碍管道正常膨胀。从管道布置设计,支吊架设置,管道壁厚和附件重量,以及现场阻尼器异常受阻四方面探讨管道异常膨胀的原因,为进一步处理该问题提供理论依据,并为高温高压蒸汽管道的设计和现场安装提出参考意见。     

火电厂蒸汽管道支吊架失效问题的研究

近年,因蒸汽管道支吊架失效而引起的电厂安全生产事故尤为突出。为了提高火力发电厂生产运行的安全性和可靠性,对蒸汽管道支吊架失效的问题进行了深入的分析和研究,找出了蒸汽管道支吊架失效的根本原因,提出了解决蒸汽管道支吊架失效问题的方法,给出了有效预防和控制蒸汽管道支吊架失效现象发生的建议和措施,为工程实际提供参考。     

弹簧在火力发电厂管道设计中的应用探讨

弹簧支吊架设计是管道支吊架设计中的重要环节,对glif与Caesar II在弹簧选型理论的相同点及差异性进行阐述,分析冷位移对弹簧选型的影响,并提出弹簧设计中应注意的若干问题。     

海底管道与多孔弹性海床的相互作用研究

针对海底管道在波浪荷载作用下的动力响应为海底管道设计中的重要因素,建立了二维有限元管—土相互作用的计算模型,并考虑了管道柔性分析管—土接触效应、摩擦系数、埋深、管径和海床渗透系数对管周孔隙水压力、管道位移和应力的影响。计算结果表明,管道浅埋情况下忽略管—土接触效应显著低估了管道竖向位移和环向应力,位于细砂中管道的动力响应小于粗砂中的管道。研究结果可为海底管道设计提供科学依据。     

蒸汽管网模拟优化技术应用

洛阳分公司蒸汽管网包括10MPa、3．5MPa、1.0MPa和0．3MPa共4个等级．其中3．5MPa和1．0MPa蒸汽管网是主要管网。两套管网均存在供汽结构不合理,管段散热损失大,管网保温材料老化及破损严重,管段外表面温发较高（在50℃以上,局部管段超过80℃）等问题。为此．根据3．5MPa和1．0MPa蒸汽管网平衡数据．作出流量平衡表．利用蒸汽管网模拟分析软件（SNAMER）建立蒸汽管网模型并进行离线模拟分析。根据模拟分析结果,提出增设一条蒸汽跨线,以提高1号汽轮机发电机入口压力和汽轮机输出功率;将热电站至化纤装置3．5MPa蒸汽母管管径改为DN500,以减少压降;将部分管线保温材料改为硅酸铝镁纤维,保护层材质改为镀锌铝皮．以减少散热损火。模拟结果显示,实施上述措施后,1号汽轮机发电机入口压力约提高0．3MPa,在耗汽量不变的情况下,输出功率可提高3％：3．5MPa年1．0MPa蒸汽管网总散热损失将分别下降24％和31％;若对部分管线进行改造,每年将节约费用500万元。     

利用ANSYS分析煤矿开采中长输管道的受力

煤矿采空区长输管道沉降是影响管道安全运行的主要因素,为量化沉降对管道受力情况的影响,一般采用去除管道表面防腐层、安装应力贴片的方式监测管道受力情况,该方法对管道防腐层有一定的破坏。采用力学有限元模拟分析软件ANSYS对采空区管道的沉降进行受力分析,计算出管道的受力情况,有效减轻了管道防腐层的破坏,为管道长期运行提供了保障。运用软件模拟管道受力的方法为今后制订和选取最优抬管方案提供了一种思路,为管道保护及管道抬升提供一定的参考。     

The synergistic effects of hydrogen embrittlement and transient gas flow conditions on integrity assessment of a precracked steel pipeline

We are reporting in this study the hydrogen permeation in the lattice structure of a steel pipeline designed for natural gas transportation by investigating the influence of blending gaseous hydrogen into natural gas flow and resulted internal pressure values on the structural integrity of cracked pipes. The presence of cracks may provoke pipeline failure and hydrogen leakage. The auto-ignition of hydrogen leaks, although been small, leads to a flame difficult to be seen. The latter makes such a phenomenon extremely dangerous as explosions became very likely to happen. In this paper, a reliable method is presented that can be used to predict the acceptable defect in order to reduce risks caused by pipe failure due to hydrogen embrittlement. The presented model takes into account the synergistic effects of transient gas flow conditions in pipelines and hydrogen embrittlement of steel material due to pressurized hydrogen gas permeation. It is found that blending hydrogen gas into natural gas pipelines increases the internal load on the pipeline walls due to overpressure values that may be reached in a transient gas flow regime. Also, the interaction between transient hydrogen gas flow and embrittlement of API 5L X52 steel pipeline was investigated using Failure Assessment Diagram (FAD) and the results have shown that transient flow enhances pipeline failure due to hydrogen permeation. It was shown that hydrogen embrittlement of steel pipelines in contact with the hydrogen environment, together with the transient gas flow and significantly increased transient pressure values, also increases the probability of failure of a cracked pipeline. Such a situation threatens the integrity of high stress pipelines, especially under the real working conditions of hydrogen gas transportation.     

油气管道并行敷设技术研究现状

我国油气管道并行敷设技术的应用和研究逐渐增多,简要介绍了我国数个大型油气管道并行敷设工程情况,对其安全性问题进行了探讨。总结了近几年来一些学者从不同角度进行研究所得的成果以及新技术、新方法在工程实践中的具体应用。分析了在管道间距的确定原则、管间热力影响和管道施工技术研究中存在的问题与不足,展望了油气管道并行敷设技术的研究方向和发展趋势。对油气管道并行敷设中的各种影响因素进行综合考虑,多条油气管道并行敷设及其合理布局、站场优化,均有待于进一步研究。     

交流输电线路对埋地金属管道稳态干扰的影响规律

随着电力和石油能源需求不断发展,电力线路和埋地金属油气管道建设在全国各地迅速展开。土地资源紧张的地区,高压输电线路和油气管道往往面临同走廊并行走线的状况。高压交流线路正常运行时,线路上的电流周期性变化产生交变磁场会在管道上产生纵向感应电动势从而引起交流稳态干扰。探讨并获得了管道外径/壁厚、管道埋深、防腐层厚度、管道防腐层绝缘电阻率等参数对交流稳态干扰的影响规律,可供电力和管道设计单位参考之用。     

埋地钢质燃气管道完整性评价方法

管道完整性评价是在役管道完整性管理的重要组成部分．检测技术则是完整性评价的重要环节。本文提出了采用外腐蚀直接评价方法进行管道外覆盖层检测及完整性评价的方法和步骤，并对各种检测方法的特点及选用原则进行了探讨，上述方法可以用于埋地钢质燃气管道的综合检测及完整性评价。     

加拿大石油出口市场和管线新动向

加拿大油砂产量快速增长,而相应的管输能力没有成长起来,2011～2012年加拿大原油大幅折价,给政府和石油生产商带来严重损失。未来加拿大西部油砂产量要实现进一步增加,必须加快加拿大石油出口管线的建设,突破原有市场格局,利用扩/新建的管线将其导向新市场,以便增加收益。文章分析了已公布的管道项目,认为加拿大国内自西向东的输油管线最有可能率先完工;通往西海岸的管线中,扩建的管线项目遇到的阻力小;南下至美国的管线前途未定。管线项目推进过程中,原住民问题、环境问题、省际协调问题是必须协调好的关键问题。     

Numerical Simulation on the Dispersion of Natural Gas Releases from a Buried Pipeline

Pipeline is a major way for natural gas transportation. Accidental gas release from a pipeline might lead to great economic losses and casualties. Therefore, it is important to investigate the dispersion characteristics of natural gas release from pipelines. Most previous studies on accidental natural gas release from pipelines mainly focused on bare pipelines and adopted simplified 2D models. This paper first established dispersion models of natural gas release from buried pipelines with high and low pressure, respectively. The numerical methods were validated by Trial 26 of the Thorney Island field experiment and the dispersion model was found to be reasonable and reliable. Then, comparative study between 2D and 3D dispersion model of released natural gas was carried out, which proved that 3D model had superiority upon the 2D model. Then the 3D model was employed to simulate dispersion process of released natural gas by changing pipeline pressure, orifice diameter, wind speed, and soil properties. Finally, the effect of leakage conditions on consequence distance was analyzed. The numerical results could provide technical supports for the design of emergency disposal equipments and urgent pipeline repairs.     

The transit oil and gas pipeline and the role of bargaining: A non-technical discussion

Transit oil and gas pipelines are growing in relevance, and face a number of topical problems. One of such issues is the problem of potential disruption from a number of sources, notably post-construction behaviour of the transit country. Present and future pipelines face the risk of continuous conflict over legal, economic and political issues. Once the pipeline is built and in operation, the threat of disruption of the pipeline by the transit country over disputed transit terms exists. This is due to two key problems: first, a shift in bargaining powers to the transit country upon construction and operation of the pipeline and, second, changes in the value of the throughput imply price changes that can affect the behaviour of the transit country. This paper discusses the role of basic bargaining principles in cross-border oil and gas pipelines involving transit through one or more countries. It finds that the motive behind the pipeline plays a key role in the prevention of potential disruptions to the pipeline due to rent squeezing. Also, although the potential of such disruptions does exist, there are a number of factors that could serve to mute the consequences of shifts in bargaining power to the transit countries.