伊拉克GARRAF地区定向井轨迹控制技术

发布时间：2018-08-08 17:52

【摘要】：伊拉克GARRAF区块地层变化复杂,在常规定向井作业当中,经常在页岩层及储层中遇到井壁缩径、坍塌、压差卡钻等井下事故,在大斜度井的施工当中作业风险更是成倍增加。同时作业方为降低作业成本,将20 口井分布在三个平台上,丛式井的施工为防碰工作带来了挑战。因此,井身轨迹控制和钻井参数优化的需求日益突出。本文针对伊拉克GARRAF地区特殊的地层情况,尤其是Tanuma地层由于脆性页岩的分布,在划眼和短起下作业中极易发生井壁坍塌导致卡钻事故的情况。利用数值模拟技术对井眼轨迹和钻具组合进行优化。根据钻具组合趋势模拟,对比不同地层的造斜率,优化钻具组合与优化轨迹相结合,优化钻井参数,解决井口间距小、防碰要求高、漏失地层造斜率低、稳斜段长等难点,在兼顾井下安全技术的前提下,实现复合钻进的最大化与轨迹的精确控制。在满足现场工具能力要求的前提下,设计出来的轨迹具有最优的井斜变化率和方位变化率、最短的井身长度、最小的扭矩和摩阻力等特点。通过现场经验的积累和软件的科学建模分析,现场利用轨迹优化来降低井下作业风险,保障工具安全,提高机械钻速,取得良好的效果。
[Abstract]:The formation change of GARRAF block in Iraq is complicated, and during the operation of regular direction well, the downhole accidents such as hole wall shrinkage, collapse, differential pressure jam and so on are often encountered in shale formation and reservoir, and the operating risk is increased exponentially in the construction of large inclined well. At the same time, in order to reduce the cost of operation, 20 wells are distributed on three platforms. The construction of cluster wells brings challenges to the anti-collision work. Therefore, the requirements of wellbore trajectory control and drilling parameters optimization are increasingly prominent. This paper aims at the special formation situation in GARRAF area of Iraq, especially for the distribution of brittle shale in Tanuma formation. The hole trajectory and drilling tool combination are optimized by numerical simulation technique. According to the simulation of drilling tool combination trend, comparing the slope rate of different formation, combining optimization of drilling tool combination with optimized track, optimizing drilling parameters, solving the difficulties such as small wellhead spacing, high requirement of anti-collision, low slope rate of lost formation, and long stable slope section, etc. Under the premise of taking into account the downhole safety technology, the maximization of the compound drilling and the accurate control of the trajectory are realized. On the premise of satisfying the requirements of field tool capability, the designed trajectory has the following characteristics: optimal well deviation rate and azimuth change rate, shortest well length, minimum torque and friction resistance, etc. Through the accumulation of field experience and the scientific modeling and analysis of software, the locus optimization is used to reduce the risk of downhole operation, to ensure the safety of tools, to improve the drilling speed of machinery, and to obtain good results.
【学位授予单位】：东北石油大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TE243

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