导向钻井下部钻具运动状态识别的理论与实验研究

From the data of field measurements and laboratory experiments, it's clear that bottom hole assembly(BHA) of steerable drilling system often experiences the destructive motion states, which leads to bit failure, drillstring fracture and the downhole advanced instruments damage or malfunction. The drilling process is often interrupted by the destructive BHA motion. Because the steerable drilling process is complex and influenced by too many factors,the mechanism of the different motion states of the BHA has never been revealed exactly, which constrains the development of recognition and control of BHA motion state of steerable drilling system.Depending on the methods of laboratory experiments and theoretical modeling, the research will concentrate on the mechanism,critical conditions and senstivity factors of the different motion states of BHA of steerable drilling system.On this basis,the kinematic model of BHA is established to study the response rules and characteristics of the various virtual sensors. Based on the experimentally mesaured multi-section trajectory data, the response data of the sensors are inverted, and its processing methods and circuit are determinded,and finally the recognition method of the BHA motion states based on the mesaured data is established. The ultimate goal is to set up the theory of the mechanism and recognition method of the different BHA motion states and lay a solid theoretical foundation to detect and control the harmful vibration of the BHA in the field.

现场实测和室内实验结果表明，导向钻井的下部钻具时常会经历极具破坏性的运动状态，导致钻头提前损坏，钻具断裂，各种井下先进仪器损坏或无法正常工作，严重影响着钻井的正常进行。但是由于导向钻井过程复杂、影响因素众多，其下部钻具不同运动状态的产生机制一直未能被准确揭示，致使导向钻井下部钻具运动状态识别与控制技术的发展受到了严重制约。本项研究拟采用室内实验和理论建模相结合的方法，对导向钻井下部钻具不同运动状态的产生机制、临界条件和敏感性因素进行研究；在此基础上，建立下部钻具运动学模型，研究各种虚拟传感器的响应规律和特点；以实验实测的多截面运动轨迹数据为依据，反演传感器的响应数据，并研究数据的处理方法和流程，通过模式识别，建立基于实测数据的下部钻具运动状态识别方法，最终形成导向钻井下部钻具不同运动状态产生机制及其识别理论体系，为现场及时发现和控制下部钻具中有害振动研究奠定坚实的理论基础。