“璇玑”推靠式旋转导向工具导向力优化的研究和应用

Optimized Steer Force Algorithm Research and Application in Push-the-Bit RSS Tool of“XuanJi”System

中海油田服务股份有限公司(以下简称中海油服)自主研发的“璇玑”系统旋转导向工具Welleader是典型的推靠式旋转导向。它依靠支撑翼肋推靠井壁,通过控制翼肋推力的合力实时进行导向作业。但是,在旋转导向钻进过程中,由于翼肋一直推靠井壁,翼肋与井壁之间存在摩擦阻力,会影响钻压传递效果,加重钻柱受力载荷,不利于提升钻井速度和保障井下工具安全。为了缓解Welleader托压问题,通过优化导向力控制算法,调整翼肋输出推力组合,在控制方式上进行优化,并通过现场实钻试验,研究导向力优化算法的应用过程和效果。中海油服通过优化导向指令,在一定程度上缓解了推靠式旋转导向托压问题,在较低导向力实施环境下具有良好的应用效果。

“XuanJi”rotary steerable system,a self-developed rotary steerable system tool by China Oilfield Services Limited(hereinafter referred to as“COSL”),is a typical push-the-bit type rotary steerable system that relies on ribs to pushagainst the wall of the wellbore to steer the bit in real-time through controlling the force of the 3 independent ribs.However,due to the continuous pushing against the wall by ribs during the steering process,there is always a frictional resistance force between the ribs and the wall of wellbore,affecting the transmission efficiency of the WOB and increasing the load on drill string,which is not conductive to improving drilling rate of penetration and ensuring safety of downhole tools.In order to alleviate the problem of Welleader supporting pressure,this paper adjusts the output thrust combination of wing ribs by optimizing the steering force control algorithm,optimizes the control mode,and studies the application process and effect of the guiding force optimization algorithm through field drilling tests.COSL Well-Tech division optimizes the steer force algorithm to alleviate the problem of Welleader in WOB dragging to some extent and performs better under applications with lower steer forces.