连续油管钻井系统流动特性研究

发布时间：2018-07-02 22:37

本文选题：连续油管 + 钻井　；参考：《长江大学》2015年硕士论文

【摘要】：连续油管(Coiled Tubing)在工业上名为挠性油管同样也可以称之为盘管。在第二次世界大战期间它就已经出现于工业应用中,自20世纪60年代逐渐引起石油工业的注意。迄今为止已有50多年的历史。连续油管钻井(Coiled Tubing Drilling,简称CTD)技术的应用和发展开始于上世纪九十年代。随着连续油管在石油钻井中的应用,连续油管的尺寸也因为在实际应用中的需要进行了一系列的改动,尺寸渐渐的变大。起初专家们预测连续油管钻井技术可能仅限于直井钻井中,但是随着连续油管钻井技术的日益革新,人们无法想象它也可以应用在定向井和水平井中。在钻井成本急剧增长和油价下跌的社会现状下,低油价和作业成本增加的情况下,缩减钻井开支以及提高钻井效率已经是解决目前石油行业现状的唯一途径了。所以在未来石油工业里连续油管钻井的市场会越来越大,数量也会大幅度的增长。事实上,在20实际50年代末的时候先进的科研工作者经过不断的探索已经研制出连续油管作业机,因为其适应能力差以及连续油管钻井技术及配套设施的原因,使得连续油管钻井技术到20世纪90年代才开始真正的进入石油钻井行业中。截至到目前,连续油管钻井在石油工业的应用主要有：钻新井、老井加深、老井侧钻水平井定向井以及欠平衡连续油管钻井等。连续油管管内流体流动时,会伴有很大的沿程阻力损失。尤其流经螺旋管段时,不同的螺旋屈曲情况导致流体所受到的离心力不断变化,出现二次流现象,对流体的阻力很大,因此,清楚连续油管钻井过程中管内流动特性,对设计连续油管作业时泵的功率、计算井底压力、最大井口压力都尤为重要。所以进行连续油管系统流动的研究具有空前的意义。所以研究连续油管管内流动具有必要的意义。本论文在前人的研究基础上,将理论模型的分析研究、连续油管钻井系统实验和数值模拟计算三种方法相相结合；其目的(1)通过实验总结连续油管管内流动特性与理论模型计算结果相结合筛选并验证理论模型的正确性和适用性。 (2)总结、筛选目前连续油管管内流体的数值模拟计算方法,结合理论模型计算结果对比并修正和完善数值模拟计算模型。 (3)同样结合连续油管钻井系统实验数据修正、完善理论模型和数值模拟计算模型。最终得到一套完整的理论、实验、数值模拟的模型为以后的连续油管钻井起到指导意义。完成了理论模型分析和计算机数值模拟计算研究,进行了不同流体和不同盘管规格以及考虑并进行了井下工具流动实验,最后将系统的理论计算、实验结果、数值模拟结果进行对比,得到以下结论： (1)综合分析连续油管钻井系统各部分理论计算模型,提出一套系统的理论计算模型。 (2)通过对盘管段连续管内牛顿流和非牛顿流计算机数值模拟计算,分析了4种数值计算模型,最终推荐选取标准K-epsilon模型并考虑粗糙厚度影响的数值模拟计算模型。并与理论计算结果进行对比,结果表明模型的正确性和适用性； (3)通过4种介质、3种滚筒规格以及考虑模拟井下工具组合的连续管钻井系统流动模拟实验研究,可得到如下结论：流体在盘管内流动时,盘管的弯曲曲率对压力损失确实有一定的影响因素,但在一定的范围内,对连续油管流体摩阻损失影响不大；用添加聚合物的试验流体进行连续油管流动实验呈现了减阻效应,其中黄原胶液以及两种模拟钻井液均出现了强烈的减阻现象；当全接和不接井下工具组合时,对实际连续油管内流动压力损失影响不大。 (4)通过对理论计算和实验结果进行对比,采用牛顿流进行连续油管钻井时,利用Colebrook-White的粗糙管计算模型和实际更接近。对于非牛顿流,必须得到针对具体流动介质的减阻率曲线,否则理论计算模型明显偏大,不适用； (5)通过数值模拟计算和实验结果的对比,针对连续油管螺旋屈曲管段的计算可以得到以下结论：与盘管相比,螺旋屈曲管段的压力损失明显偏大,在同等尺寸螺距情况下,油套径向间隙越小,压力损失就越大。
[Abstract]:Coiled Tubing is also known as a flexible tubing in industry. During the Second World War, it appeared in industrial applications and gradually attracted the attention of the oil industry since 1960s. So far, it has been for more than 50 years. Continuous tubing drilling (Coiled Tubing Drilling, abbreviated as CTD) technology The application and development of the operation began in the 90s of the last century. With the application of continuous tubing in oil drilling, the size of continuous tubing has been changed by a series of changes in practical application, and the size has gradually increased. At first the experts predicted that the continuous tubing drilling technology may be confined to the straight well drilling, but with the continuity of continuous oil pipe drilling. With the increasing innovation of oil pipe drilling technology, it is impossible for people to imagine that it can also be used in directional and horizontal wells. Under the situation of rapid increase in cost of drilling and falling oil price, under the condition of low oil price and operating cost, the only way to reduce the cost of drilling and to improve the efficiency of drilling has been the only way to solve the current situation of the oil industry. So the market for continuous tubing drilling in the future oil industry will become more and more large and the quantity will increase greatly. In fact, at the end of the 20 50s, the advanced researchers have developed the continuous tubing operating machine through continuous exploration, because of their poor adaptability and continuous tubing drilling technology and matching. The continuous tubing drilling technology has not really entered the oil drilling industry until 1990s. As of now, the application of continuous tubing drilling in the oil industry mainly include the drilling new well, the old well deepened, the horizontal well directional well and the underbalanced continuous tubing. When it flows through the spiral pipe, the different spiral buckling causes the centrifugal force of the fluid to change continuously, and there are two flow phenomena, and the resistance to the fluid is very large. Therefore, the flow characteristics of the pipe in the continuous tubing drilling process are clearly calculated and the power of the pump in the design of the continuous tubing operation is calculated. The bottom hole pressure and the maximum wellhead pressure are particularly important. So it is of unprecedented significance to study the flow of the continuous tubing system. Therefore, it is necessary to study the flow in the continuous tubing pipe. On the basis of the previous research, the analysis and research of the theoretical model, the experiment of the continuous oil pipe drilling system and the numerical simulation calculation are three kinds of research. The purpose (1) is to sum up the correctness and applicability of the theoretical model by combining the flow characteristics in the continuous tubing pipe with the theoretical model calculation results and to verify the correctness and applicability of the theoretical model. (2) to sum up, select the numerical simulation method of the current fluid in the continuous tubing pipe, and compare the results of the theoretical model and improve and improve the calculation results. Numerical simulation model. (3) combining the experimental data of continuous tubing drilling system to improve the theoretical model and numerical simulation model. Finally, a complete set of theoretical, experimental and numerical simulation models for continuous tubing drilling will be of guiding significance. The theoretical model analysis and computer numerical simulation calculation are completed. In the study, different fluid and different coil specifications were carried out and the downhole tool flow experiments were taken into consideration. Finally, the theoretical calculation, experimental results and numerical simulation results were compared, and the following conclusions were obtained: (1) comprehensive analysis of the theoretical calculation model of the various parts of the continuous tubing drilling system and a set of systematic theoretical calculation models were put forward. (2) 4 numerical models are analyzed by numerical simulation of Newtonian and non Newtonian flow in pipe section continuous tube. Finally, the numerical simulation model is recommended to select the standard K-epsilon model and consider the influence of rough thickness. The results are compared with the theoretical calculation results, and the results show the correctness and applicability of the model. (3) through the study of 4 kinds of medium, 3 kinds of drum specifications and the flow simulation experiments of continuous pipe drilling system considering the combination of simulated downhole tools, the following conclusions are obtained: when the fluid flows in the coil, the bending curvature of the coil does have certain influence on the pressure loss, but in a certain range, the friction loss of the continuous tubing fluid is lost. The effect of the experimental fluid on the continuous tubing flow was reduced by the addition of the experimental fluid added with the polymer, of which the xanthan glue and the two simulated drilling fluids all had a strong drag reduction phenomenon. When the whole and the unconnected tools were not connected, there was little effect on the flow pressure loss in the actual continuous tubing. (4) through the theory of the theory Compared with the experimental results, when using Newton flow for continuous tubing drilling, the calculation model of Colebrook-White's rough pipe is closer. For non Newton flow, the drag reduction curve must be obtained for the specific flow medium, otherwise the theoretical calculation model is obviously larger and not applicable; (5) numerical simulation and experiment are carried out. Compared with the helical buckling tube section of the continuous tubing, we can get the following conclusion: compared with the coil, the pressure loss of the spiral tube section is obviously larger. Under the same size, the smaller the radial clearance, the greater the pressure loss.
【学位授予单位】：长江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE24

【参考文献】