一种新型多级可变径稳定器工作机理研究

摘要

针对目前国内可变径稳定器结构复杂 、制造成本高等问题,设计了一种主要用于水平井井眼轨迹微调的新型多级可变径稳定器.该稳定器能在钻井液驱动力作用下通过改变销钉在行程控制轮导向滑槽中的状态来实现多级变径,针对其结构特点,对其工作原理进行了介绍.基于纵横弯曲法理论,并考虑均布载荷及弯矩等因素的联合作用,建立了包含多级可变径稳定器的井下钻具组合的力学模型,得到了钻井液驱动力与稳定器支撑块伸出长度之间的关系式,计算了不同支撑块伸出长度所需最小钻井液驱动力和钻头侧向力的值,结果表明该可变径稳定器能实现增斜 、降斜和稳斜功能.研究成果为多级可变径稳定器的结构设计和优化提供了技术指导.%Since the complicated structure of domestic variable diameter stabilizer and the high manufacturing cost ,a new multistage variable diameter stabilizer was designed for fine-tuning horizontal well trajectory .The diameter of stabilizer could achieve multilevel changes by changing the state of the pin in the stroke control wheel guide chute under the control of drilling fluid driv -ing force ,and its working principle was introduced in view of its structural characteristics .Based on the theory of vertical and horizontal bending method and considering the combined effect of load and bending moment ,a mechanical model of the downhole drilling tool assembly with multi-stage variable diameter stabilizer was established ,the relational expression between the drilling fluid driving force and the length of the stabilizer support block was obtained and the minimum drilling fluid driving force and the drill bit tilt angle in different extension length of the support block were calculated .The results show that the multistage variable diameter stabilizer can realize the function of increasing slope ,decreasing slope and stabilizing slope ,which can provide techni-cal guidance for the structural design and optimization of multistage variable diameter stabilizers .