碳钢在不同类型海底沉积物中的腐蚀行为

采用弱极化曲线拟合和交流阻抗测量技术,研究了低碳钢在3种不同颗粒度的海底沉积物中的腐蚀行为.得到了有关的腐蚀速度和电化学参数,并初步探讨了腐蚀机理.     

某海底管道腐蚀的原因

采用腐蚀模拟试验、腐蚀产物分析、宏观分析等方法分析了某海底管道的腐蚀原因。结果表明:引起海底管道腐蚀失效的主要原因为垢下腐蚀。     

湿天然气CO2顶部腐蚀研究

渤海某海底管道在天然气输送过程中发生顶部腐蚀,导致停产检修。本研究以管道CO_2顶部腐蚀发生的过程和机理为基础,建立海底输气管道CO_2顶部腐蚀的预测计算模型,并进行实验室挂片CO_2顶部腐蚀模拟实验以及现场海底输气管道CO_2顶部腐蚀检测数据验证,实现对海底输气管道CO_2顶部腐蚀速率的预测。     

海底天然气管道腐蚀与防护

海底管道的腐蚀是影响管道系统可靠性及其使用寿命的关键因素.对海底输气管道在海洋环境的腐蚀产生机理以及影响因素进行分析,介绍海底输气管道的腐蚀防护措施,对防腐涂层和阴极保护设计、使用以及目前腐蚀防护措施存在的问题进行探讨.     

天然气管道环焊缝缺陷部位的腐蚀沉淀机理

为了深入分析天然气管道的“梗阻”现象,采用金相法和能谱仪对靖边某气田典型的有大量沉积物管道进行了焊缝和沉积物结构及成分分析.结果表明,焊缝缺陷处的腐蚀和沉淀机理为管内发生CO₂腐蚀、缝隙腐蚀和H₂S腐蚀,产生了氧化物、氯化物和硫化物等腐蚀产物.随着腐蚀产物的逐渐堆积,其阻隔了管子材料与腐蚀性介质,使得腐蚀速率减慢,沉积物转为以粉尘为主.沉积物堆积到一定高度时,天然气的流向改变,管道顶部的腐蚀变为冲刷腐蚀,腐蚀速率加快,管道壁厚严重减薄,危害管道的正常安全运行.     

海底管道的防腐蚀

埋入海底泥土中或者浸于海水中用来输送石油、天然气、海水、淡水和污水的海底管线是投资巨大的永久性工程,一般要求在不加维修的条件下正常服役20年以上.但在腐蚀条件苛刻的海水、海泥环境中,钢质管线的外部腐蚀比陆地管线严重得多,而且很难维修,因此,做好防腐蚀十分重要.     

某海底管道失效原因

某海底管道在投产3a后发生了腐蚀穿孔,通过检测数据分析、腐蚀速率模拟计算、实物管段检测分析、内腐蚀模拟试验及缓蚀剂有效性分析等方法对其失效原因进行了分析。结果表明,投产后CO2和H2S含量增高,缓蚀剂未达到预期效果,产生严重的CO2局部腐蚀,这是造成海底管道腐蚀穿孔失效的主要原因。针对类似的失效情况,提出了海底管道安全运行的应对措施。     

LN209井油管沉积物下方腐蚀行为

通过扫描镜（ＳＥＭ）对ＬＮ２０９井油管的沉积物进行观察,发现主要有三层沉积物方腐蚀行为靠近金属基体的较为致密,另外两层为疏松状的物质,通过双速流动实验装置和电偶腐蚀速度测量仪研究了ＬＮ２０９井油管的沉积物下方的腐蚀规律。     

海底注水管线缓蚀剂的筛选优化

针对海底注水管线的运行工况,建立了室内缓蚀剂评价方法,对15种国内外缓蚀剂样品利用腐蚀失重进行了评价.研究海水温度、流速和缓蚀剂添加浓度对腐蚀速度影响的同时,对缓蚀剂的水溶性及配伍性也进行了综合评定.     

空蚀磨损和腐蚀在发动机缸套失效中作用分析

对K38发动机缸套失效进行研究,阐述缸套失效的原因,研究缸套失效的形式及缸套失效过程中空蚀磨损和腐蚀的作用.结果表明:缸套的表面破坏,是以空蚀磨损破坏缸套中的石墨为主;缸套的次表层破坏,是由于空蚀磨损和腐蚀交互作用,使缸套破坏速度加快;缸套深层局部破坏,以沉积物下腐蚀为主,空蚀磨损为沉积物下腐蚀创造条件.     

Prediction of marine sediment corrosion by fuzzy clustering analysis

Along with the development of marine industries, especially marine petroleum exploitation, more and more pipelines are buried in the marine sediment. It is necessary and useful to know the corrosion environment and corrosiveness of marine sediment. In this paper, field corrosion environmental factors were investigated in Liaodong Bay marine sediment containing sulfate‐reducing bacteria (SRB) and corrosion rate of steel in the partly sediment specimens were determined by the transplanting burying method. Based on the data, the fuzzy clustering analysis (FCA) was applied to evaluate and predict the corrosiveness of marine sediment. On that basis, the influence factors of corrosion damage were discussed.     

原油高温腐蚀性能研究

本文综述了国内外原油高温腐蚀性能的研发现状,分别归纳分析了高温硫腐蚀和高温环烷酸腐蚀在腐蚀机理及其影响因素、腐蚀预测、以及腐蚀控制措施方面的研究进展。同时探讨了存在的问题和可能的重点研究方向。     

Effects of anaerobe in sea bottom sediment on the corrosion of carbon steel

The in‐situ study of steel corrosion in sea bottom sediment (SBS) was carried out by Transplanting Burying Plate method (TBP method). It was found that the corrosion rate of steel in the sea bottom sediment with sulfate reducing bacteria (SRB) could be as high as ten times of that in sea bottom sediment without SRB. The experiments in simulated sea bottom sediments with different SRB contents by artificial culturing showed that the electrochemical behavior of steel in the sea bottom sediment with SRB was different from that without SRB. SRB altered the polarization behavior of steel significantly. The environment was acidified due to the activity of SRB and the corrosion of steel was accelerated. The corrosion of carbon steel in sea bottom sediment is anaerobic corrosion, and the main factor is anaerobe. There are SRB commonly in SBS, and the amount of SRB decreases along with the depth of sediment. Because of the asymmetry and variation of sea bottom sediment, the most dangerous corrosion breakage of steel in SBS is local corrosion caused by SRB. So the main countermeasure of corrosion protection of sea bottom steel facilities should be controlling of the corrosion caused by anaerobe.     

Effect of different offshore seabed sediment on steel corrosion

A series of simulation experiments on corrosion behaviour of carbon steel (A₃ Steel) and low alloy steel (16Mn steel) in marine atmosphere (MA), seawater (SW) and seabed sediment (SBS) including rough sea sand, fine sea sand and seabed mud were carried out indoors for a year or so by means of individually hanging plates (IHP) and electrically connected hanging plates (ECHP). Results showed that the corrosion rates of A₃ and 16Mn steel in marine environment were in the order: MA > SW > SBS by the IHP method, MA > SBS > SW by the ECHP method. The corrosion rates of steels in the water/sediment interface were directly proportional to the grain size of the SBS by the ECHP method, but those of steels in the water/sediment interface did not vary with the grain size of SBS by the IHP method. The corrosion rate of low alloy steel was a little higher than that of carbon steel. The corrosion in seabed sediment was mainly determined by the macrogalvanic cell (oxygen concentration difference cell) between steel plates in different sediment and depth.     

金属材料长周期海水腐蚀规律研究

常用金属材料在我国的青岛、舟山、厦门和榆林4个海域的飞溅、潮差、全浸3个海洋区带中暴露1、4、8和16年的长周期腐蚀试验工作进行了研究，得到了长周期的海水腐蚀数据及其腐蚀规律．提出了一种海水腐蚀性的评价方法和一种综合评价材料耐蚀性的方法．     

奥氏体不锈钢焊接接头在不同酸性介质中的腐蚀行为

研究了奥氏体不锈钢焊接接头在不同酸性介质中的腐蚀行为。采用模拟环境和特定腐蚀环境，对奥氏体不锈钢腐蚀率进行对比。结果发现，在硫酸-硫酸铁腐蚀液中实验时间以沸腾1．5h较为合理。焊接线能量大的奥氏体不锈钢耐腐蚀性差。     

常减压装置常用钢材在高温原油馏分中的腐蚀研究

利用高压釜模拟常减压装置中的腐蚀环境,采用腐蚀失重法并结合SEM,研究了4种常减压装置常用钢材在高温原油馏分中的腐蚀行为,分析了馏分、材质、温度的影响规律。结果表明,原油馏分的酸值、S含量和盐含量越高,对20钢腐蚀性越强,3种原油馏分对20钢的腐蚀性强弱为：脱盐后原油＞常二线馏分＞常一线馏分。提高钢材中Cr,Ni和Mo等合金元素的含量有助于提高其抗腐蚀能力,4种钢材在高温原油馏分中的抗腐蚀性能优劣为：316钢＞304钢＞1Cr5Mo钢＞20钢。温度对钢材在高温原油馏分中的腐蚀行为会产生多方面的影响,腐蚀速率总体上随着温度的升高而增大,某些温度范围内可能出现腐蚀速率极值。     

The effect of tannins and pH on the corrosion of steel in wood extracts

Tannins and pH are often cited as factors that affect the corrosiveness of wood yet there are few data to confirm these statements. The purpose of this paper is to systematically investigate the effect of tannins and pH on corrosion of metals in wood. Four wood species known to vary in both their pH and extractives were chosen and extracted with water. The pH, tannin content, and corrosion rate of carbon steel were determined for each extract. To test if pH and tannin were the only factors influencing corrosion, “synthetic” extracts were made by adding tannins to distilled water and adjusting the pH. At a given pH, increasing the tannin content inhibited corrosion and at a given level of tannin content, lowering the pH increased corrosion. An isocorrosion map as a function of pH and tannins was developed by using simple kinetic models to extrapolate the data. The data may be useful in estimating the relative corrosiveness of new, nonmetallic wood preservatives based upon the chemistry of naturally durable wood species.     

碳钢在废弃钻井液中的腐蚀行为研究

采用失重法,动电位扫描、扫描电镜及俄歇电子能谱等手段,研究了碳钢在废弃钻井液化学脱稳处理过程中的腐蚀行为。结果表明：化学脱稳后的废弃钻井液腐蚀性增加,氧含量、ＰＨ值、温度、固相含量、金属阳离子及混凝剂等都对体育馆２行为有很大的影响;除氧和添加吸附型缓蚀剂可减缓废弃钻井液的腐蚀。