论文标题
水平段中高密度油基钻孔液应用的现场测试
Field Tests of High-Density Oil-Based Drilling Fluid Application in Horizontal Segment
论文作者
论文摘要
在坚硬的较脆的longmaxi地层页岩层中，水平段的运行经验很好地表明，高密度的油基钻孔液（HDOF）诱导的下孔工作状况，通常是高体温，高压和固相位和固体相位的，将直接影响Wellbore壁的稳定性。侧重于底孔渗透压和固相含量以及一系列密度还原现场测试的影响，我们发现了一些有用的对策。在本文中，我们研究和讨论高渗透压和操作度量的影响，并提供现场测试的详细信息，这些详细信息表明在底部孔处保持较高的渗透压可以降低底部孔的地层孔隙压力，从而扩大流体密度窗口，并保持井眼壁的稳定性。通过改善HDOF配方，例如使用新的处理剂（例如聚合物修饰的纳米密封剂，超微米少量稀释剂量添加剂）并优化HDOF的固体粒径分布，我们可以有效地解决底部孔问题。因此，事实证明，水平钻孔操作中“压力控制钻孔 +密度降低”的现场测试被证明能够降低孔断层的复杂性，提高穿透率并节省整体成本。
The operation experience of horizontal segment well in the southern Sichuan area within the hard brittle shale layer of Longmaxi formation demonstrates that the high-density oil-based drilling fluid (HDOF) induced down-hole working condition, which is typically high-temperature, high-pressure and solid-phase-dominant, will directly impact the stability of the wellbore wall. Focusing on the impact of bottom-hole osmotic pressure and solid phase content and a series of density-reduction field tests, we found some helpful countermeasures. In this paper, we study and discuss the impact of high osmotic pressure and operation measures, and provide details of the field tests which indicate that maintaining a higher osmotic pressure at the bottom-hole can reduce the formation pore pressure of the bottom hole, widen the fluid density window, and maintain the stability of the wellbore wall. By improving the HDOF formula, such as using new treatment agents (e.g. polymer modified nano-sealing agent, ultra-micro barite weight additive) and optimizing the solid particle size distribution of HDOF, we can effectively address the down-hole problems. The field test of "pressure-controlled drilling + density reduction" in horizontal drilling operations is therefore proved to be capable of reducing the complexity of down-hole faults, improving the rate of penetration, and saving the overall cost.
