钼酸盐缓蚀剂在自来水中的电化学行为

曾一度较普及的铬系、磷系缓蚀剂,由于对环境产生影响,其应用受到了限制,而作为非磷系且无毒的钼酸盐缓蚀刑逐步得到应用。为此,通过电化学极化曲线与交流阻抗实验,研究了钼酸盐系列缓蚀剂在自来水中对20A碳钢的缓蚀情况。指出钼酸盐与正磷酸盐的复配具有明显的协同效应而与锌盐之间不存在协同关系。     

钼酸盐复配缓蚀剂对铜的缓蚀性能研究

通过采用静态失重法研究钼酸钠与苯并三唑复配对铜在40℃时的长江水介质中的缓蚀情况,并分析温度和时间对铜缓蚀剂的影响,研究结果表明:1)BTA单独使用时,对铜缓蚀性能随BTA浓度的增加而增强。在40℃下,BTA单体浓度为40-60mg/L时对铜的缓蚀效果较好。2)钼酸盐与BTA复配使用时,40℃时,最好的复配浓度为30mg/L+40mg/L。3)钼酸盐与BTA复配40℃时比60℃下对铜的缓蚀效果好。     

盐水钻井液中钻杆的钨酸盐系缓蚀剂研究

为了延长盐水钻井液中G105钢钻杆的使用寿命,通过电化学阻抗谱(EIS)的测量分析,对在盐水钻井液中G105钢钻杆的钨酸盐系复合缓蚀剂进行了研究,并采用失重法通过室内动态模拟试验对所获配方进行了验证.结果表明,钨酸盐与有机胺A有较好的协同效应,复配而成的缓蚀剂具有较好的缓蚀效果;最佳配比为:钨酸盐∶有机胺A=1∶1(质量比),复配缓蚀剂在最佳用量为0.12%(质量分数)时,缓蚀率在85%以上.     

曼尼希碱复配缓蚀剂的酸洗缓蚀性能

为减少曼尼希碱用量并保证其缓蚀效果,以甲醛、苯乙酮和有机胺为原料合成了曼尼希碱主剂,通过正交试验,将其与十二烷基酚聚氧乙烯醚(OP-10)和油酸钠(SO)进行复配,在20%HCl介质中研究了其对Q235碳钢的缓蚀效果并对复配条件进行了优化。采用失重法、电化学方法、大气采样中和滴定法对复配缓蚀剂的性能进行对比分析,并考察不同温度对复配缓蚀剂性能的影响。确定的复配缓蚀剂最佳配方为:0.70%曼尼希碱,0.10%OP-10,0.20%SO。结果表明,经过复配的缓蚀剂缓蚀效果和抑雾效率均比单独添加曼尼希碱有明显的提高,在60℃20%HCl中,曼尼希碱质量分数为0.5%时,Q235钢的腐蚀速率为1.58g/(m2.h),缓蚀率达到99.31%,抑雾率为80.53%;本复配缓蚀剂是以抑制阳极为主的混合型缓蚀剂,具有良好的耐高温性能。     

天然海水中钼酸盐复合缓蚀剂对A3钢的缓蚀效果

已有的海水缓蚀剂多局限于模拟环境,在天然海水中的适应性较差.将A3钢浸于添加了钼酸盐复合缓蚀剂的海水中,研究了浸泡时间、缓蚀剂组分投加顺序、海水温度、氯离子浓度、pH值、杀菌剂类型对缓蚀剂缓蚀效果的影响.结果表明:试片在含有钼酸盐复合缓蚀剂的海水中浸泡40 min的阻抗谱直径比浸泡24 h的稍大,在空白海水中浸泡40 min和24 h的阻抗谱直径相差较大,即复合缓蚀剂对浸泡时间有一定的适应性;缓蚀剂组分投加时先加入钼酸盐,试片自腐蚀电位最大,阳极极化曲线斜率变化较明显,该缓蚀剂是以钼酸盐为主剂的复合型缓蚀剂;复合钼酸盐缓蚀剂在海水温度为30～60℃、pH值为6～10内使用,缓蚀率变化较小,对冷却水系统常用的杀菌剂也有良好的适应性,并适用于NaCl质量分数小于8%的海水循环冷却系统.     

再生水循环冷却系统中缓蚀阻垢剂的优化研究

针对再生水用于循环冷却系统引起的腐蚀结垢问题,采用碳酸钙沉积法、旋转挂片法、表面微观分析技术和电化学方法,结合正交试验设计和动态模拟试验装置,对钼系缓蚀阻垢剂的缓蚀、阻垢性能进行试验研究,确定了钼系配方的最优组成,并探讨了钼系缓蚀阻垢剂的协同作用机理。结果表明:复配药剂的最佳组成为2-膦酸丁烷-1,2,4-三羧酸(PBTCA)5.0 mg/L,丙烯酸-2-丙烯酰胺-2-甲基丙磺酸共聚物(AA/AMPS)5.0 mg/L,钼酸盐8.0 mg/L,锌盐2.0 mg/L,BTA 1.0 mg/L。该复配药剂的阻垢机理包括膦酸基(-PO_3H_2)的晶格畸变、羧基(-COOH)的螯合增溶以及长链结构的分散作用,是一种典型的阳极型缓蚀剂。     

H－93氯乙烯转化器循环冷却水缓蚀阻垢剂的研制

通过静态、动态、电化学测试和现场试验证明，研制的Ｈ－９３缓蚀阻垢剂具有高防护性能。这种缓蚀阻垢剂以钼酸盐为主要缓蚀组分，按照缓蚀剂的协同效应原理，与无机缓蚀剂Ｇ、有机缓蚀剂Ｅ复配并添加适量阻垢剂Ｂ而组成。Ｈ－９３缓蚀阻垢剂为白色粉末固体，水分＜３％，ｐＨ（０．２％０溶液）≥７，热分解温度≥２３０℃，当浓度达２００×１０（－４）％时，在高温循环冷却水中具有优良的缓蚀阻垢性能。     

油酸基咪唑啉类缓蚀剂的复配及其缓蚀性能研究

以丙炔醇、丁炔二醇为复配剂对油酸基咪唑啉缓蚀剂进行了复配研究.利用红外光谱分析(IR)静态失重法、Tafel极化曲线、SEM等手段考察了咪唑啉中间体的结构及复配对咪唑啉缓蚀剂缓蚀性能的影响.研究结果表明,炔醇复配在很大程度上改善了咪唑啉缓蚀剂的缓蚀效果,丙炔醇的复配效果优于丁炔二醇.丙炔醇复配可以达到99%以上的缓蚀率,腐蚀速率可以达到2g/(m2·h)以下.咪唑啉缓蚀剂与炔醇通过协同效应可以使吸附在金属表面的缓蚀剂吸附膜更加均匀、致密.     

H—93氯乙烯转化器循环冷却水缓蚀阻垢剂的研制

通过静态、动态、电化学测试和现场试验证明，研制的Ｈ－９３缓蚀阻垢具有高防护性能。这种缓蚀阻垢剂以钼酸盐为缓蚀组分，按照缓蚀剂的协同效应原理，与无机缓蚀剂Ｇ、有机缓蚀剂Ｅ复配并添加适量阻则组成。Ｈ－９３缓蚀阻垢剂为白色粉末固体，水分〈３％，ＰＨ（０．２‰溶液）≥７，热分解温度≥２３０℃，当浓度达２００×１０＾－４％时，在高温循环冷却水中具有优良的缓蚀垢性能。     

复配气相缓蚀剂对多种金属大气腐蚀的综合保护作用研究

为了应对海洋大气环境中电子设备容易被腐蚀的难题,制备了一种复配气相缓蚀剂。通过半封闭空间挥发减量试验、缓蚀膜疏水性表征、模拟环境和海洋大气环境试验等评价了复配气相缓蚀剂对钢、T2紫铜、黄铜、银、铝等电子设备常用金属的气相缓蚀性能。结果表明:复配气相缓蚀剂对以上金属均具有显著的缓蚀作用,其中对钢的缓蚀率为86.9%,对T2紫铜为58.7%,对黄铜为96.2%,对银和铝在模拟腐蚀环境中具有一级气相缓蚀能力,是一种性能优良的电子设备多金属大气腐蚀综合防护材料。     

G-105钢在盐水钻井液中的腐蚀行为

为了解决盐水钻井液对钻具的腐蚀,通过对现场钻杆腐蚀产物的EDS分析发现,其主要成分为铁的氧化物Fe2O3;盐水钻井液对钻具的腐蚀主要是氧的去极化腐蚀,且腐蚀产物疏松,对钻杆保护作用较差.通过室内动态模拟试验发现,随着温度升高和转速增加,G-105钢在盐水钻井液中的腐蚀速率都会增加;含盐量较低时(＜3%)泥浆中的盐分对溶解氧的排驱作用较小,主要起增强导电性作用,此时,G-105钢在盐水钻井液中的腐蚀速率随着盐含量的增加而增大,随后,盐对溶解氧的排驱作用占优势,腐蚀速率随盐含量的增加而降低.     

钻杆焊缝刺漏原因分析

通过刺孔形貌观察、扫描电镜分析、能谱分析、化学成分分析、金相检验以及硬度测试等方法,对钻杆焊缝刺漏失效的原因进行了分析。结果表明:失效钻杆在焊缝区域存在一定面积的焊接灰斑缺陷,使得钻杆焊缝区的结合强度、疲劳强度以及冲击韧度大大降低,从而导致了该次钻杆焊缝区的早期刺漏失效。最后根据钻杆失效的原因,提出了相对应的改进措施和建议。     

Study of 4, 4′-methylenebis-cyclohexanamine as a high temperature-resistant shale inhibitor

In order to develop high-performance water-based drilling fluid with the aim of meeting the increasing requirement of drilling industry, highly inhibitive and high-temperature-resistant shale inhibitors are essential. In this study, 4, 4′-methylenebis-cyclohexanamine was introduced as a potential shale inhibitor. The inhibitive properties of the amine compound in comparison with currently available polyether diamine inhibitor were evaluated using bentonite inhibition test, shale cuttings hot-rolling dispersion test, linear swelling test, and pressure transmission test. The inhibitive mechanism was investigated with zeta potential measurement, X-ray diffraction analysis, and contact angle measurement. The results indicated that 4, 4′-methylenebis-cyclohexanamine can inhibit shale hydration and dispersion effectively, and prevent pressure transmission to a certain extent, performing better than that of polyether diamine. Furthermore, the new diamine provides reliable thermal stability as high as 220 °C, preserving the benefits of high-temperature wells application. This novel diamine inhibits shale hydration and dispersion with the combination of chemical inhibition and physical plugging. The intercalation into the interlayer of clay with monolayer collapses the hydrated clay structure and expels the water molecules. After adsorption, clay surface became more hydrophobic, which prevents the imbibition of water. The variation of solubility separates the compound from the solution, which can plug the micro-pores of shale and prevent fluid invasion.     

Failure analysis of drill pipe: A review

Although the drill pipe is a simple tool in the drilling industry, it is the most used and important one. The drillstring failure has two general forms: wash-out and twist-off. These failures begin with mechanical, thermal and corrosion fatigue cracks. On the basis of previously conducted researches, the failure of drillstring is not unknown. However, the occurrence of drillstring failure still is too much. The main reason for this can be due to complex loading, combined stresses and different types of vibrations and moreover, the corrosive and erosive behavior of drilling mud that makes the total condition of the well so difficult to analyze. In this paper, the attention is focused on the analysis of drill pipe failure and the fatigue crack is represented for the root cause of drill pipe failure. The aims of most of published papers are to examine how and why a specific drill pipe is failed and just the main reason of failure for that drill pipe is discussed in detail. In this paper all metallurgical and mechanical aspects of failure that can occur for a drill pipe, are considered and discussed. And finally, this comprehensive review leads to a conclusion that categorizes the primary sources of drill pipe failure into seven major groups and makes some recommendations to avoid them.     

钻柱纵向振动分析与应用

利用钻柱纵向振动数学模型,分析了钻柱轴向应力振幅分布曲线和钻柱中最大轴向应力幅频曲线的特征以及钻井液粘度、激励位移、减振器位置对钻杆中最大轴向应力振幅的影响。分析表明：钻柱中轴向应力振幅沿纵向呈波状分布,其最大值在钻柱底部或钻杆中;钻杆中的最大轴向应力振幅随转速的变化曲线呈凹坑形,为了保护钻柱,应该选择凹坑中间的转速带;钻杆中的最大轴向应力振幅和钻柱底部的轴向应力振幅随转速的变化趋势并不完全一致,以后者作为判断钻柱是否共振和优选转速的指标不够准确,而应以前者作为该指标;钻杆中的最大轴向应力振幅与激励位移大致成正比;钻井液粘度越高,钻杆中的最大轴向应力振幅越小;减振器位置可以改变钻柱纵振系统的固有频率,从保护钻柱角度考虑,低转速时,减振器应紧靠钻头安装,高转速时,减振器应与钻头保持一定距离;通过优选钻具组合和转速,防止钻柱共振是预防钻具失效的有效措施     

φ139.7 mm×10.54 mm G105钻杆刺穿失效分析

采用宏观分析、化学成分分析、力学性能试验、金相检验、扫描电镜断口分析及能谱分析等手段对某规格为φ139.7 mm×10.54 mm的G105钻杆的刺穿原因进行了分析。结果表明:钻杆刺穿的实质是早期疲劳失效;蹩钻、跳钻等钻柱振动引起钻杆上产生的严重交变应力是导致钻杆失效的主要原因;钻井液中的溶解氧对钻杆外表面造成氧腐蚀并形成腐蚀坑,促进了疲劳裂纹的萌生;钻铤直接过渡到钻杆,截面变化突然,使应力集中加剧,也是导致钻杆发生疲劳失效的原因之一。建议在钻井液中添加除氧剂和缓蚀剂,并适当降低钻压,调整钻井参数,避免钻柱剧烈振动。     

Investigation of drill pipe rotation effect on cutting transport with aerated mud using CFD approach

In drilling with aerated mud, appropriate hole cleaning has a great impact on decreasing the drilling time and cost. Thus, investigating the impact of diverse drilling parameters such as pipe rotation on the hole cleaning looks as a key. In this study, the combination of $k-\epsilon$ turbulent model and Eulerian-Eulerian multiphase model was used to investigate the three phase flow in the concentric annulus. Furthermore, the collision of cutting – cutting, cutting-drill pipe and cutting-well was considered in the simulations. In the first step, for validating the computational setup, the simulation outcomes were compared with the previous experimental works. The impact of pipe rotation on hole cleaning at various water and air flow rates, inclination and cutting sizes was scrutinized. The simulation results demonstrated that the impact of pipe rotation on the hole cleaning can be different depending on the different hole conditions. In the low inclination and air rates, rising the pipe rotation from 0 to 75 RPM brings about dropping the cutting concentration, but increasing the pipe rotation from 75 to 125 RPM comes about raising the cutting concentration. On the other hand, in low inclination and high flow rates of air, rising the pipe rotation causes a high accumulation of cutting. Lastly, at high inclination, the cutting concentration in annulus decreases with increasing the pipe rotation and this is independent of air and water flow rates. The simulation outcomes also showed that the impact of pipe rotation on hole cleaning at large cutting size is not as much as small cutting size.     

氢氧化钠中复合缓蚀剂对铝的缓蚀协同效应

采用失重法、电化学极化曲线法和扫描电镜,研究了铝在氢氧化钠介质中的几种缓蚀剂复配后的缓蚀协同效应作用,它由三聚磷酸钠、间苯二酚,糠醛,丙炔醇和十二烷基苯磺酸钠以一定比例复合而成,同时对其作用机理进行了探讨。结果表明：该复合缓蚀剂的总浓度达到0．2％时,腐蚀速率达到1．867g·m^2h^-1。     

钻杆扭矩法预测冲击地压的研究

钻杆扭矩法是通过测试钻孔过程中钻机对钻杆输出扭矩的大小来判断煤矿冲击地压危险性的方法,具备许多传统方法不可替代的优点,是一种很有发展的预测预报方法。该文建立了钻屑过程中钻杆的力学模型,得出钻杆扭矩与煤体应力、煤体性质及钻进速度的关系,分析表明:钻屑过程中,煤体应力增大时,钻杆扭矩增大,钻屑推进力减小;钻屑推进速度增加时,钻杆扭矩增加,钻屑推进力增大;煤体强度增大时,钻杆扭矩增加,钻屑推进力增大。利用钻杆扭矩测试装置,测试了不同煤体应力条件下钻屑扭矩的变化规律。理论和实验结果均表明:使用相同的钻机及钻具,按照指定速度对同一性质的煤层打钻时,钻杆扭矩随着煤体应力的增大而增大,钻杆扭矩变化规律与煤体应力及钻屑量具有较好的一致性,通过测试钻杆扭矩的变化规律,得出钻孔处煤体应力场的分布化规律,进而预测煤层冲击危险性。研究结果为煤矿动力灾害预测预报提供一定的理论与实验基础。