可控弯接头密封结构设计研究

Design and Research of Controllable Bent Sub Seal Structure

旋转导向钻井工具在国内已有较大的发展,现已成型的导向钻具几乎全为钻头推靠式导向方式。可控弯接头导向钻具的设计研究为国内全旋转钻头指向式导向钻具的发展奠定了理论基础,其研制尚处于起步阶段,有许多关键技术亟待解决。简要介绍了旋转导向钻井工具结构和工作原理;针对其结构特点和实际的井下工作环境,对其密封结构进行重点研究。设计一种带有压力补偿的组合密封结构,为存在动态压力突变的钻井液-润滑油这一位置的密封问题提供一种理想的解决方案,并对关键密封部件进行有限元分析,以保证密封结构具有径向补偿、耐高温、耐高压、耐腐蚀、抗冲击、长寿命等特点,为可控弯接头原理样机的试制与相关原理性试验奠定良好的理论基础。

Rotary steerable drilling tool has initial development in our country,but the prototypes almost are the push-the-bit system.The design and research of controllable bent sub for all do-mestic rotating and point-the-bit type steering downhole development laid a solid theoretical foun-dation,its development is in its infancy,and there are a number of key technical problems to be solved.An overview of the structure and working principle are given,which focus on the seal for its structural characteristics and actual underground work environment.A combination seal with pressure balance components are designed according to its structure characteristic and practical working condition which solved the seal problem between the dynamic pressure drilling fluid and lubricant.It also does the finite element analysis to the critical sealing components in order to meet the design performance requirements radial compensation high temperature high pressure corrosion resistance impact resistant and long life.A good theoretical basis is laid for its prototype making and the relevant principles test.