为了提高靶点精度,连通救援井与事故井,需要利用探测定位工具确定事故井的井眼位置,而国内目前缺乏相关的成熟技术.针对这一问题,提出了一种基于对称激励的瞬变电磁救援井探测定位方法,根据麦克斯韦方程建立了探测距离和方位的计算模型,研制了救援井探测定位工具样机,进行了救援井电磁探测定位工具井下试验.试验结果显示,电磁探测定位工具的最大探测距离可达24.0 m,距离误差小于10％,方位误差小于5°.研究结果表明,该电磁探测工具可对事故井的井眼进行准确定位,可为救援井与事故井的直接连通提供保障,并为形成具有我国自主知识产权的救援井探测定位和连通技术奠定了基础.

Usually a relief well can not hit the blowout well with the first trial,and need ranging tools to realize the junction between them and kill the latter.The uncertainty of their relative positions,as well as the performance of currently-used ranging tools and the environment suitable for their functioning,were analyzed.The selection scheme of the injection point and the first ranging point were given.Combined with the drilling technology for the relief well,the ranging plans for different stages were designed,and the methods to improve the reach and accuracy of the ranging were proposed.The results of this paper have been successfully applied in the backup design of several offshore relief wells,providing reference and technical guidance for the design and implementation of relief well's ranging plan.

Because there is no standard or actual design experience to serve as a reference in well trajectory design for deepwater relief wells in China,work was done to develop selection charts that would connect points(targets)in accordance with principless for deepwater relief well locations.They were developedin a way to respect the restricted conditions in drilling relief wells,they were individually evaluated for each of the four kinds of common relief well trajectories:"J"shape,parallel close connected shape,directly connected,and"pass-by"shapes.Research results showed that the well trajectory with"pass-by"shape had a great advantage in improving the measurement range and position accuracy.Consequently,it has been determined to be the preferred well trajectory for deepwater relief wells,and divided into four stages,i.e.approaching,positioning,tracking and intercepting.The key design factors as the entrance angles at all stages and well spacing,etc.,have been studied,and it was determined that when the maximum inclination angle of the relief well is less than 60°,the dogleg should be not greater than 3°/30m,which determines the basic design method of well trajectory in deepwater relief wells.The method has been used for designing well trajectories in a deepwater relief wells in the CNOOC overseas block.Research results showed the newly-developed method could provide valuable guidance for designing well trajectories in deepwater relief wells in China.

Drilling relief well is an effective way to control blowout at present. To study electromagnetic detection for relief wells, by using well-ground current injection method, the relief well detection model based on point source has been built, finite element software has been used to analyze impacts of electrode arrangement, current size, the distance between blowout well and electrode, and casing length on density of aggregation current on casing in the well with incident. The research results show installation of ground electrodes on casing may facilitate current aggregation on casing of well with incident; the longer the distance between electrode and casing, the lower the density of aggregation current will be, in addition, the in-flow current and density of aggregation current on casing are in linear relationship; density of aggregation current increases with increase of casing length, but amplitude of such increase decreases with the increase of casing length. Relevant researches have verified effectiveness and applicability of the model for aggregation current on casing in wells with incident. The research results can provide a theoretical basis for developing tools detecting connectivity with the relief well.

常规方法调整弯角马达工具面时作业效率低,易发生工具面漂移、托压等复杂情况.基于顶驱和MWD系统研制了一套弯角马达工具面动态控制系统,该系统可自动判断工具面偏移情况并发送指令至顶驱定位系统,实现连续滑动钻进过程中对工具面的实时监测和自动控制.仿真测试及现场试验结果表明,所研制的弯角马达工具面动态控制系统具有良好的快速响应及稳定性,滑动钻进时工具面可控制在目标值±10°范围内,具有较好的现场应用价值.

Due to uncertainties of wellbore track, appropriate detection and location tools must be used to connect the relief well and the accident well. Thus, the research of electromagnetic detection and location system is important to the design and operation of relief wells. This paper studies the basic principle of electromagnetic detection and location system (EDLS) and analyzes the calculation method of casing collection current in accident wells using the EDLS and its distribution characteristics; the paper also investigates the calculation methods of relative distance and relative direction between the relief well and the accident well; in combination with the practical applications of the EDLS, the effects of casing parameters, cutting angle, hole drift angle, and formation and other parameters in the accident well on the measurement effects and applications of the EDLS are analyzed; building on the analysis of the EDLS, the distance measurement and connection in the design of a super deepwater relief well in the South China Sea is ifnished. This paper can provide a theoretical basis for the development of EDLS for relief wells and offer a reference for the application of EDLS in the design and operations of relief wells.

随着中国海油挺进深水战略的实施,深水井必须具有完整的备用救援井方案,但国内尚没有海上救援井设计作业的相关规范指南及经验,因此需要对救援井设计、作业的关键技术进行研究与分析.在对比分析救援井和常规定向井区别的基础上,认为救援井设计的技术难点在于测距、连通及压井作业,开展救援井作业时机、救援井数量确定和井口位置选择等基本设计,救援井测距定位方案、连通方案、井眼轨迹设计及定向作业等中靶设计,以及救援井压井作业等关键技术分析,总结各关键技术的具体实施细则,可为海上救援井设计及作业提供参考与指导.本文部分研究成果已在南海LW21-1-1井等深水井的备用救援井方案设计中获得成功应用.

回顾了中国海洋石油钻井从浅海走向深海的历程及中国南海近几年已钻深水井概况,较系统地总结和讨论了深水钻井工程核心技术问题,阐述了海洋深水钻井从设备到工艺与浅水及陆地钻井的主要差别,并讨论了深水钻井设计考虑的主要因素和钻井设计方法概要等,为深水钻井工程设计提供参考.

Deepwater oil and gas exploration and development has become a hot spot in oil industry, but accidents like blowout oc-cur from time to time. The drilling of relief well is a very effective way to kill a blowout well. How to accurately determine the relative location of the relief well from the blowout well is a key to the relief. Using software to simulate blowout well with a radius of 139.7 mm, a 1 A current source and a ground electrode were set in its vicinity, then study was conducted on, the effects of the distance between current source and blowout well, the distance between the two electrodes and the radius of the blowout well on the current density on the casing in the blowout well. The research results show that the nearer the blowout well is to the relief well, the greater the current density is on the casing in the blowout well, and that the location of minimum current density on the casing in blowout well is closer to the location of electric current source. The location of the minimum current density in the blowout well is determined by the location of the point current source. The smaller the blowout well radius is, the greater the change of current density amplitude is, and the greater the amplitude of its above current density is. The research findings provide some theoretical basis for drilling offshore relief wells.

对国内外各种救援井测距系统的基本原理和发展现状进行了全面分析,从探测距离、精度、入射角、测距时间等方面对比分析了主动测距系统和被动测距系统,同时结合救援井测距系统对2010年墨西哥湾事故救援井作业流程及测距工具在其救援井作业过程中的应用进行了研究,重点分析了救援井作业过程中测距作业流程.该项研究结果对可能出现的救援井作业具有一定的借鉴和参考意义.

Now,the mainly power of the rotary steerable drilling tools that had commercial applied were:battery,mud power,turbine generators,etc.The rotary steering drilling tool that was devel-oped by CNOOC Research Institute was powered by the drilling mud.It could control the well trajectory by the three pads’hold in and out that would get the bit depart from the axes of the well,and then realized the orient drilling.Then,the effect of flow and characteristics of the mud, and the effect of nozzle combination of the bit were analyzed,and a reference to the tool’s field test was provided.The results of the field test proved the correctness of the theoretical calcula-tion,and this study would provide theory basis for the development of the mud-powered rotary steerable drilling tools.

旋转导向钻井工具空间姿态的测量和控制是实现井眼轨迹控制的关键.针对MWD工具不能直接测量旋转导向钻井工具的工具面问题,分析了旋转导向钻井工具的空间姿态.利用欧拉定理,通过动坐标与大地坐标的旋转变换,建立了旋转导向钻井工具空间姿态的测量和确定模型,并在现场试验中取得了良好的井眼轨迹控制效果.

Combined with the characteristics of rotary steerable drilling system,the drilling fluid pressure pulse was taken as the downward signaling mode of the rotary steerable drilling tool and the deep study was carried out on the transmission characteristics of the drilling fluid pressure pulses in the system.The influences of various drilling parameters no the pulse amplitude were analyzed and the time characteristics of the pulses were obtained.Thereby the suitable command system and the coding method were designed combined with the transmission characteristics of drilling fluid pressure pulses and the characteristics of the rotary steerable drilling tool.The field test has demonstrated that the developed downward signaling system has high decoding rate and meet the needs of the rotary steerable drilling tool.