机器学习算法在混输管道内腐蚀预测的应用

基于内腐蚀直接评价理念中的腐蚀分析方法，结合管道内检测结果，采用线性回归以及神经网络算法，分析不同因素对腐蚀的实际影响效果。分析过程中，对管道腐蚀缺陷进行了统计分析，研究了缺陷深度符合指数分布。为更好的预测分析管道腐蚀程度，筛选了腐蚀缺陷作为拟合数据。基于学习出的拟合公式，预测了管道在未来不同工艺条件下的腐蚀趋势。经计算，两种算法预测结果基本一致。按照该算法，能够实时根据管道运行工艺参数预测未来腐蚀程度。     

多相混输管道内侧的腐蚀试验

应用CFL-1型动态腐蚀试验环道系统,研究了几种管线钢在多相混输管道内不同流动状态下的腐蚀速率以及不同工艺条件下的段塞流的腐蚀速率,了解各种流型的腐蚀特性及温度、压力等工艺参数对混输管道内腐蚀的影响规律.     

长输管道工艺站场埋地管线腐蚀分析

当前,长输管道工艺站场埋地管线腐蚀穿孔现象已经对整个工艺站场埋地管道安全运行造成了严重威胁。而这场埋地管道的腐蚀现象主要是由于设计、施工以及管理等各个方面因素综合影响下形成。长输管道工艺站场埋地管线在社会发展过程中发挥出了非常重要的作用,因此必须要对其腐蚀情况进行深入分析,在此基础上,提出相应的解决措施,这样才能充分保证长输管道工艺站场埋地管线实现安全运行。     

油气开采环境下管道的协同腐蚀及防护研究进展*

服役于高温高压 CO₂ / H₂S 环境下的管道腐蚀是油气田中急需解决的重要问题。CO₂、H₂S 及 Cl^- 是油气田管道中常见的腐蚀介质，其与温度、压力、pH值、含水率、流速等外界因素间的协同腐蚀作用会导致管道严重腐蚀，研究这些腐蚀介质与外界因素的协同腐蚀机制以及减缓管道腐蚀的措施有着重要的科学意义和经济价值。针对油气开采过程中金属管道的腐蚀问题，综述了 CO₂、H₂S 及 Cl^- 在协同腐蚀过程中起到的作用，讨论了温度、压力、pH 值、含水率及流速等实际工况条件下外界因素对腐蚀过程的影响。论述了现有管道腐蚀防护技术与工艺的特点：合金元素的掺杂可以改善腐蚀形貌，提高腐蚀产物层的致密性，等离子体扩渗与镀膜技术能够制备一层致密的保护层来吸收部分腐蚀介质并减缓腐蚀速率，缓蚀剂的添加可以减缓管道的阴极或阳极反应或形成减缓腐蚀速率的吸附层。最后展望了未来油气田管道防护技术的发展方向：为了有效地对油气开采环境下的管道进行保护，需要进一步研究腐蚀介质和外界因素间的协同腐蚀作用，模拟实际工况下的腐蚀环境， 对等离子体扩渗与镀膜技术、缓蚀剂等现有的防护技术进行系统的试验测试。     

天然气管道内腐蚀的原理及直接评价

内腐蚀是H2S,CO2等酸性气体和水汽对管道内壁造成的腐蚀,常见于天然气管道埋深,管径等条件发生改变处。目前对内腐蚀的防护主要通过管道内涂层和添加缓蚀剂实现。通过内腐蚀的直接评价技术(DG-ICDA)可有效对管道做出内腐蚀评价。近年来内腐蚀受到重视的程度提高,未来对内腐蚀的研究方向主要为新材料、新的输送工艺、气体质量等,同时继续完善内腐蚀的评价技术等相关理论。     

水送翻转法复合内衬施工工艺

随着油田的开发，集输管道的腐蚀愈来愈严重，影响了原油生产的正常进行。为此，在腐蚀较严重的管段进行了衬里试验，收到良好的效果。文中介绍了水送翻转法复合内衬的施工工艺、参数控制及工艺特点．该工艺具有造价低、工期短、寿命长等优点。     

一种新型在线腐蚀监测系统在集输天然气管道的应用

本文阐述了一种新型在线腐蚀监测技术在某气库集输天然气管道的应用。根据短距离高压天然气集输管道特点，分析集输管道腐蚀现状及腐蚀检测技术应用情况，结合油田储气库作业区点检情况，确定集输管道的腐蚀关键位置进行监测，开发适用于高压天然气集输管道的腐蚀监测系统及腐蚀率计算等算法，研发腐蚀监测系统配套硬件设施，实现对天然气集输管道监测点位腐蚀速率的监测。     

高压加氢装置管道选材研究

针对高压加氢装置中典型的腐蚀工况，论述了不同工艺介质下管道材料的选材标准、选材依据及焊接接头热处理要求等。结论表明，高压加氢装置中，非腐蚀性油品和设计温度200℃以下的新氢管道选择普通碳钢材料。设计温度200℃以下的含硫化氢介质的管道选择抗硫抗氢的碳钢材料。设计温度≥200℃的氢气和硫化氢管道，选择321或347材料。设计温度≥240℃含环烷酸介质的管道，选择316L材料。铵盐腐蚀环境的管道跟随油品油气介质选材，铵盐腐蚀控制需在选材和工艺管道设计上共同优化。高压往复进料泵出口碳钢管道、临氢振动的压缩机进出口碳钢管道、湿硫化氢腐蚀碳钢管道需要进行焊接接头热处理。321材质在操作温度399～427℃，347材质在操作温度427～454℃时，根据工业实践经验，可不进行焊接接头稳定化热处理。     

脱水天然气输送管道腐蚀失效分析

川东油气田天然气集输管道多次出现管道破裂穿孔管事故,利用Ｘ衍射、扫描电镜、电子探针、热重分析等方法对现场的腐蚀挂片和集输管道中收集的腐蚀产物进行了分析检测,结果表明：集输管道虽然经过三甘醇脱水工工艺处理,仍曹受较严重的Ｈ２Ｓ腐蚀,腐蚀形态主要为局部抗蚀,集输管道中形成的腐蚀产物万分 比较复杂,主要为ＦｅＳ,ＦｅＳ２,Ｆｅ３Ｓ４和Ｆｅ９Ｓ８,同时存在一定量的铁的氧化物和其它化合物;管道中腐蚀产物的热     

油田工艺管道腐蚀与防腐措施研究

油田工艺管道中输送的介质主要有石油、天然气、含油污水、高压水等,同时也包括酸、碱、盐等杂质。油气资源关系到国防安全和人民生活的方方面面,其重要性不言而喻,而由于腐蚀给油田工艺管道的安全运行带来严重危害,如腐蚀穿孔引起油、气、水的跑、冒、滴、漏造成的经济损失,对土壤、地下水、空气等造成环境污染,火灾、爆炸引起的人员伤亡等。因此,研究油田工艺管道内、外腐蚀的机理,有针对性的提出相应的防腐措施,延长管道的使有寿命,具有重要意义。     

时效制度对AA6156铝合金拉伸性能和断裂韧性的影响

研究了NZ2锆合金板材在不同温度、不同浓度的碘蒸气中的力学行为,并进一步通过扫描电镜观察其断口形貌。结果表明,试验温度为400 ℃,其发生应力腐蚀的临界碘蒸气压约为102 Pa;横向试样较轧向试样更具应力腐蚀敏感性;温度升高能够促进裂纹尖端的应力释放,有利于碘能被更有效地吸附到裂纹尖端,加快对锆合金的腐蚀作用,从而降低了应力腐蚀的临界碘浓度。在高温碘蒸气中,断口腐蚀产物主要为锆的氧化物;虽然碘蒸气对锆有较强的腐蚀作用,但是不足以穿透其表面的保护膜,而局部变形则可以促进碘对金属锆的腐蚀。     

含应力特性试件的设计制作及湿H2S应力腐蚀实验

为了预测石油化工设备在材料特性、应力特性和环境特性下的应力腐蚀开裂，设计制作了能实现材料特性和应力特性的新型试件，用电测法监控加载，实测相应的应力值，再将含应力特性试件在NACET－1F－9标准实验溶液中进行试验，达到了预期的目的。新型试件结构简单、加载方便，它既能在实验室实验，也能模拟设备的应力水平，随设备一起长期运行。从而可以为设备在实际的应力腐蚀环境中安全运行提供重要的数据，为研究设备的应力腐蚀开裂提供了一种行之有效的方法。     

Effect of alloying additions on the structure and corrosion properties of zinc coatings

Conclusions Prolonged corrosion tests in a stream of sea water on samples galvanized in baths with different alloying additions showed that the corrosion resistance of zinc coatings in sea water can be improved by alloying with 0.01% Ti+0.05% Mg+0.1% Al and with 0.01% Ti.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 5, pp. 45–47, May, 1974.     

Long-term high-velocity oxidation and hot corrosion testing of several NiCrAl and FeCrAl base oxide dispersion strengthened alloys

Several oxide dispersion strengthened (ODS) alloys have been tested for cyclic, long-term, high gas-velocity resistance to oxidation at 1100°C and hot corrosion at 900°C. Both nominally Ni-16Cr-4Al and Fe-20Cr-4.5Al ODS alloys were subjected up to 2500 cycles, where each cycle consisted of 1 hr in a hot, Mach 0.3 combusted gas stream followed by a 3-min quench in an ambient temperature, Mach 0.3 air blast. For comparison to existing technology, a coated superalloy was simultaneously tested. The ODS iron alloy exhibited clearly superior behavior, surviving 3800 oxidation and 2300 hot corrosion cycles essentially unscathed. While the ODS nickel alloys exhibited adequate oxidation resistance, the long-term hot corrosion resistance could be marginal, since the best life for such alloys under these conditions was only 1100 cycles. However, the hot corrosion resistance of the ODS Ni-base alloys is excellent in comparison to that of traditional superalloys.     

Powder stream characteristics in cold spray nozzles

The exponential increase of industrial demand in the past two decades has led scientists to the development of alternative technologies for the fast manufacturing of engineering components, aside from standard and time consuming techniques such as casting or forging.Cold Spray (CS) is a newly developed manufacturing technique, based upon the deposition of metal powder on a substrate due to high energy particle impacts. In this process, the powder is accelerated up to considerable speed in a converging-diverging nozzle, typically using air, nitrogen or helium as a carrier gas. Recent developments have demonstrated significant process capabilities, from the building of mold-free 3D shapes made of various metals, to low porosity and corrosion resistant titanium coatings.In CS, the particle stream characteristics during the acceleration process are important in relation to the final geometry of the coating. Experimental studies have shown the tendency of particles to spread over the nozzle acceleration channel, resulting in a wide exit stream and in the difficulty of producing narrow tracks.This paper presents an investigation on the powder stream characteristics in CS supersonic nozzles. The powder insertion location was varied within the carrier gas flow, along with the geometry of the powder injector, in order to identify their relation with particle trajectories. Computational Fluid Dynamics (CFD) results by Fluent v6.3.26 are presented, along with experimental observations. Different configurations were tested and modeled, giving deposited track geometries of copper and tin ranging from 1 mm to 8 mm in width on metal and polymer substrates.     

Corrosion of HR3C heat exchanger alloy in a biomass fired PF utility boiler

Detailed microscopic examinations have been conducted on two, temperature‐regulated probes (commercial HR3C heat exchanger alloy) after being exposed to biomass flue gas inside a PF boiler for 3770 h at 600°C and 650°C respectively. Corrosion of the tube proceeds via scale formation and internal element depletion. Three characteristic types of internal corrosion have been identified depending on their position relative to the flue gas passage and deposit/flue gas chemistry. Severe, mainly internal corrosion occurs at down‐stream locations where higher potassium chloride content exists within the deposit. Corrosion mechanisms corresponding to each type of internal corrosion have been proposed based on further laboratory tests and thermodynamic analysis. The increased temperature (650°C) causes slightly higher material wastage for the alloy.     

Korrosionsverhalten nichtrostender ferritisch-austenitischer Stähle in Natronlauge

Corrosion performance of duplex steels in caustic solutions The corrosion performance of stainless ferritic-austenitic steels (DIN 1.4362, DIN 1.4462, Uranus 50 and Ferralium 255) was investigated in boiling sodium hydroxide solutions. It was found that these steels are corrosion resistant in NaOH solutions up to 30 mass-% with corrosion rates lower than 0.01 mm/a. The mass loss rate increases with increasing NaOH concentration, reaching a maximum in 60 mass-% NaOH solution. Small flow rates (e.g. 0.08 m/s; rotating disc) increase the corrosion rate by a factor of 6 with respect to stagnant conditions. However, further increase of flow rate yields no additional enhancement of the corrosion rate up to 1 m/s. Under conditions of free corrosion no stress corrosion cracking was observed at constant deflected samples or at tensile probes tested to failure under CERT-conditions in boiling 20–70% NaOH solutions. The corrosion attack is uniform in NaOH solutions up to 30 mass-%. In more concentrated NaOH solutions the dissolution rate of the austenitic phase is slightly higher than the ferritic phase. The corrosion products contain more nickel than the base material.     

阳极极化处理对2024铝合金电偶腐蚀行为的影响

将2024铝合金与电位较正的另一种金属钛连接加速腐蚀,通过测试电偶腐蚀电流的分布曲线,对比2024铝合金经阳极化处理前后的电偶腐蚀敏感性.腐蚀后,通过观察表面形貌,分析了该铝合金的电偶腐蚀行为,表明阳极极化处理对改善其电偶腐蚀敏感性有很明显的作用,降低了电偶腐蚀电流,减少了平均腐蚀失重.     

Metallic filters by powder metallurgy

It was during the late 1930’s that sintered bronze filters were first produced because of their strength, corrosion resistance, and efficiency in filtering fine particles from a stream of liquid or gas. Ten years ago stainless steel filters were first produced by powder metallurgy, and only two years ago metallic fiber filters were put on the market. Today powder metallurgy promises many interesting new developments in this field.     

2024与2124铝合金电偶腐蚀行为的对比研究

将2024和2124铝合金与电位较正的钛合金（TC4）联接加速腐蚀,通过测试电偶腐蚀电流的分布曲线对比研究将铝合金经阳极化处理后的电偶腐蚀敏感性。采用表面形貌观察分析2×××系列铝合金的电偶腐蚀行为。结果表明,纯化可以减小材料的腐蚀电流密度和腐蚀电位,但效果不太明显,而阳极氧化处理可以明显降低其腐蚀敏感性,是防护电偶腐蚀的重要措施之一。