受压油管屈曲变形与内外层杆管接触分析

针对机械采油工程中杆管偏磨问题, 考虑直井内受压油管屈曲变形与套管、 抽油杆的双层接触, 以及油管和抽油杆的变截面结构和环空间隙, 采用有限元结构稳定性分 析方法对受压油管进行失稳计算, 将求得的多阶失稳波形叠加值作为油管柱的初始位移, 再 采用大位移和接触非线性分析方法模拟受压油管屈曲变形, 以及与套管和抽油杆间的接触摩 擦, 为套管内受压油管屈曲变形分析提供了一种计算方法.     

Tubing modifications for countercurrent chromatography: Investigation of geometrical parameters

Countercurrent chromatography (CCC) is a separation technique which may be described as a combination of a great number of liquid–liquid distributions of analytes in a two-phase solvent system with liquid chromatography (LC) features. Even optimized CCC separations currently provide a lower number of theoretical plates when compared to LC. For this reason, instrumental advancements are indispensable to, at least partly, overcome this drawback. Recently, we found that improvement of the classic CCC coil, that is using a long hollow tubing, may be achieved by the introduction of tubing crimpings which increase the stationary phase retention. In this study, we systematically investigated the effects of three geometrical parameters (crimping depth, distance between two crimpings as well as partial or complete crimping of the tubing) on the stationary phase retention by a factorial design of experiments approach. Separation efficiency tests were performed with two groups of analytes: fatty acid methyl esters (FAME) in the n-hexane/acetonitrile (HAcn) and alkyl p-hydroxybenzoates in the n-hexane/tert-butylmethylether/methanol/water solvent system. The most narrow crimping distance and the deepest crimping of the tubing were the best configurations in the examined flow rate range.     

Improvement of precision for pipetting blood serum samples into a graphite furnace

Graphite furnace atomic absorption spectrometry is a well-established technique for trace metal determination in blood and serum samples. For this kind of samples, a R.S.D. of up to 10% is considered acceptable, especially for those elements, the concentrations of which do not allow high dilution. Among the reasons that contribute to an increase of the S.D. is the retention of proteins (and analyte) in the sample dispenser capillary, because proteins might be adsorbed on polymeric surfaces. In the present work, the interaction protein/polymer was studied, considering the amount of protein that could be retained by the capillary, the influence of sample dilution, time of contact and the possible co-adsorption of metals. Serum proteins were retained in the capillary, depending on the material (Tygon>silicone rubber>poly(tetrafluorethylene)); dilution did not prevent the adsorption, and only 30 s of contact were enough for the adsorption to occur. Using a column filled with PTFE powder (60 mesh), it was possible to observe that metals were co-adsorbed to a large extent. Water, diluted nitric acid or aqueous solutions of Triton X-100 were not able to promote the complete desorption of the proteins retained by the polymeric materials. Total elution was achieved with methanol, and its use as rinse solution decreased the R.S.D. (n=10) for aluminium, manganese and chromium determination in serum to <10%.     

油管接头台阶密封面的接触压力及密封性能

锥形油管螺纹接头在拧紧过程中如何保证其密封性能,是目前工程实践中的难点问题之一。以具有台阶密封面结构的锥形油套管接头为研究对象,通过对内外螺纹受力与变形分析和相互啮合时所满足的变形协调方程和位移方程,在弹性范围内建立了能够计算锥形油套管接头拧紧时台阶密封面上接触压力的计算模型。利用粗糙密封表面微观接触分析方法,以某一具体的API锥螺纹接头为例,计算模拟了螺纹拧紧圈数和初始间隙对台阶密封面上接触压力及密封性能的影响规律,获得了相应的变化曲线,并对这些曲线进行了分析。此研究有助于实际应用中合理确定油管接头拧紧圈数,为确保实现良好密封提供理论依据。     

钢筋混凝土简体结构的抗震性能分析研究

针对某29层的钢筋混凝土筒体结构建筑,在建立空间杆系-层模型的基础上,对三种不同水平加强层设置的混凝土超高层筒体结构进行地震作用下的计算分析,并对不同结构布置进行比较,总结出此类超高层结构在设置加强层后结构内力及抗震性能的变化规律,对带加强层筒体结构的设计和构造措施作一些探讨．     

120吨转炉水冷配管管路改造

二炼钢厂4座120吨转炉自投产后,水冷配管系统因漏水导致非计划停炉频繁,其严重影响了转炉正常的生产节奏,针对此现状二炼钢厂对其进回水管路冷却系统进行改造,改造后杜绝了此类事故发生。     

连续油管作业的数字孪生及其下入性

连续油管是油气行业的重要工具,实际作业下入过程的存在与传动理论分析结果差异较大,倒是现场作业面临多次下入,造成连续油管的安全隐患。针对其下入性问题,提出了连续油管的数字化模型,建立了下入过程的接触状态算法、载荷分析物理模型,对下入的全过程进行同步孪生,实现了对下入连续油管实时计算的管柱承载状态与强度校核,以及对连续油管下入性的全过程分析。结果表明：连续油管下入过程中的接触状态随下入深度实时变化,管径比和摩擦系数是下入过程自锁判定的显著影响因素。本研究所提出的分析方法可有效服务于连续油管现场作业以及实时作业安全评估,并为连续油管的使用寿命分析提供重要依据。     

外科移植用可扩张编织管道的研制

介绍了医用可扩张管道的纤维材料选择与性能，管道的结构设计与编织工艺。还测试了该管道的扩张性能，并与理论分析进行了比较。     

连续油管注入器液压系统

连续油管作业可节省大量的上卸扣时间,并能减少能量消耗,因此应用范围不断扩大．连续油管作业设备的核心是注入器,根据注入器的主要功能,提出一种新的注入器液压系统,并对其组成、工作原理和性能特点进行了详细的分析．该液压系统的主驱动回路与辅助驱动回路分开,主驱动回路主要满足负载特性的要求,辅助驱动回路主要保证灵活的操作性能,这样便于系统的调试和维护．在主驱动回路中采用闭式容积调速和节流调速相结合的控制方式,分别满足载荷扭矩为正和为负的负载特性要求．这种控制方式特别适用于大功率系统．分析表明：新的液压系统既满足负载和操作要求,又节能可靠,是一种理想的连续油管注入器液压系统．     

玄武岩纤维管材在石油领域的应用现状及前景分析

 玄武岩纤维是一种新型材料,具有成本低廉、绿色环保、应用广泛等优点,因此在国防、工业、民用等各个领域得到广泛应用.近年来,俄罗斯等国家将玄武岩纤维制成管材,成功应用到石油领域,包括油气井套管、油管及地面输油管道.本文系统阐述了玄武岩纤维套管、油管及地面输油管道的主要类型及性能指标,并分析了玄武岩纤维管材应用于石油领域的优势及其实际应用效果,证明在石油领域应用玄武岩纤维管材从技术上是可行的.同时,从原材料、技术指标、需求、技术难点等方面探讨了玄武岩纤维管材在中国石油领域的应用前景.