油套管腐蚀速率影响因素敏感性试验研究

油管是油井生产的关键器材,井下管柱的腐蚀是油田开采过程中面临的重要问题,分析各因素对腐蚀速率的影响规律,从而提出有层次的防腐建议至关重要。结合海上油田生产实际和各种影响因素,通过自主研制的腐蚀试验装置,模拟了温度、含水率、CO₂分压、铬含量等因素对其影响程度,并利用灰色关联度的方法对各个影响因素进行了排序和分析。腐蚀损害因素的关联度排序为:温度>含水率>CO₂分压>铬含量。影响腐蚀速率最主要的因素为温度和含水率,在深度较深或者地层稳定梯度较高的井,首先应考虑管材的腐蚀,而在油田前期设计管柱材料时,要对全生命周期内的含水率进行综合考虑,以最大含水率条件为极限腐蚀情况。     

自动垂直钻井工具分类及发展现状

从石油钻井和地质钻探两方面阐述了自动垂直钻井技术的原理及优点,按照不同结构及工作原理对自动垂直钻井工具做出分类,并简要分析了各类工具的优缺点。随后在上述分类基础上系统归纳了国内外现有垂直钻井工具及其技术特点,剖析了国内外自动垂直钻井工具之间的技术差距。最后总结出自动垂直钻井工具存在的问题,指出工具今后的发展趋势为小型化、可取心、高精度和长寿命,并对其未来的研究思路与方法提出建议:对执行机构零部件结构和布局进行优化,在减小工具外径的同时增大工具内部空间,使工具在小口径井眼垂直钻进的同时还能进行取心作业;对电控式垂直钻井工具的测控传感器及其密封系统进行优化改进,使工具整体耐温耐压性能得到提高;对机械式垂直钻井工具的偏重平台在井下复杂环境下的响应规律进行研究,并探索相应的误差抑制补偿方法,以提高工具的井斜控制精度。     

244.5 mm套管三胶筒隔离封隔器研制

为了解决老式隔离封隔器容易出现刮损失效和密封性能差的问题,采用具有不同硬度组合的三胶筒式密封结构,研制了一种适用于海上油田防砂作业的新型隔离封隔器。该隔离封隔器由密封机构、锁紧机构、坐封机构和心轴组成。通过优化胶筒的参数,以及在胶筒两端安装铜环,使胶筒的压缩力更加均匀。室内试验时,正反向验封压力均达到41.4 MPa,坐封后自锁状态稳定。现场应用表明,该封隔器设计合理、性能可靠。     

磁性颗粒/碳纤维轻质柔软复合材料制备及其吸波性能

为开发兼具电损耗和磁损耗的新型轻质柔软吸波复合材料,采用聚丙烯腈(PAN)基预氧丝毡浸渍金属盐溶液,经高温处理工艺制备了磁性颗粒/碳纤维轻质柔软复合材料。通过弓形法吸波测试、X射线衍射、X射线能谱分析、扫描电子显微镜观察等方法对材料性能进行表征和分析。结果表明:所制备的复合材料由碳纤维和具有磁损耗性能的Fe—Co—Ni、Fe₃O₄、Fe—Ni、Fe—Co等颗粒组成,磁性颗粒沿着纤维轴向均匀分布,电损耗与磁损耗间的协同作用使磁性颗粒/碳纤维复合材料表现出优异的吸波性能。当处理温度为650 ℃和700 ℃时,试样电磁波发射损耗小于-5 dB的吸收波段分别为8.6~18 GHz和10~18 GHz,电磁波反射损耗小于-10 dB的吸收波段分别为13.9~18 GHz和14~18 GHz。结果表明,过高或过低的处理温度会降低材料电磁波损耗,通过调节处理温度可控制材料的吸波性能。     

Surface Modification of Co3O4 Nanosheets to Promote Peroxymonosulfate Activation for Degradation of Atrazine

Catalysis Letters - This study proposed a new facile route to rational creating oxygen-vacancy (Vo)-rich surface of Co3O4 nanosheets by acetic acid leaching. The acid leached Co3O4 nanosheets was...     

碳化钒析出对X80管线钢焊接热影响区韧性的影响

通过Gleeble-3500热模拟机对钒(V)含量分别为0.06%和0.02%的X80管线钢进行了峰值温度为1350℃和750℃的焊接热模拟试验,利用硬度计和光学显微镜(OM)分别分析了焊接热模拟试样硬度和试样中马氏体-奥氏体岛状组织(M-A)的数量、尺寸和形貌。利用透射电镜(TEM)对母材、粗晶区和部分相变区中粒子析出进行了表征。结果表明,与0.02%含V量X80管线钢相比,0.06%含V量的X80管线钢由于V含量较高,在受到多道次焊接热循环影响时,部分相变区有较大量碳化钒(VC)粒子析出,明显阻碍位错运动,使其强度明显提高的同时脆性增大、塑性变形难以进行,导致其焊接热影响区韧性下降。     

New solitary wave solutions of (2+1)-dimensional space–time fractional Burgers equation and Korteweg–de Vries equation

In this article, via the improved fractional subequation method, the fully analytical solutions of the (2+1)-dimensional space–time fractional Burgers equation and Korteweg–de Vries equation involving Jumarie’s modified Riemann–Liouville derivative have been derived. As a result, with the aid of symbolic computation, many types of new analytical solutions are obtained, which include new solitary wave, periodic wave and rational wave solutions. The graphical representations show that these gained solutions have abundant structures.     

Preparation and electromagnetic-wave-absorption properties of a nitrogen-doped carbon–supported iron(II,III) oxide composite

Journal of Materials Science: Materials in Electronics - A single material with dielectric or magnetic loss behavior cannot optimally absorb electromagnetic waves because such waves are composed of...     

A multi-focus image fusion algorithm in 5G communications

In this paper, we first build a mobile cloud platform that users can upload multi-focus images or download full-focus images through the 5G network. Then we design a method named Region Mosaicking on Contrast Pyramid (RMCP) for image fusion on the cloud platform. In the RMCP method, we apply the Sum-Modified-Laplacian to measure the focus of the multi-focus image, and use the density-based region growth algorithm to segment the focus region mask for each image. Finally, the mask is decomposed into a mask pyramid to monitor the mosaic region of the contrast pyramid. The experimental results show that RMCP based on 5G network outperforms other methods. In addition, RMCP is suitable for mobile devices.