摘要
从钻井连续循环系统上卸扣卡瓦的工作机理入手,弄清了钻杆工作时的受力状态。将钻杆看作厚壁筒,采用弹性力学中的拉美公式求解钻杆内外受压的应力问题。钻杆外表面承受的摩擦力矩,看作圆筒扭转问题进行求解。考虑管壁的变形的影响,解决了钻井连续循环系统上卸扣卡瓦卡紧力的计算难题,给出了上卸扣卡瓦卡紧力的计算公式。实例计算表明采用Φ127或Φ140钻杆进行连续循环钻井,上卸扣卡瓦卡紧力最好取19MPa;为提高钻杆的安全系数,应尽量采用厚壁钻杆;在卡瓦的设计时,可考虑加大卡瓦长度的方法减小卡瓦卡紧钻杆时的卡紧力。该计算方法可以用于指导钻井连续循环系统上卸扣卡瓦的设计。
Based on the operational principle of on/off slip of continuous-circulation system,the forced state of drill pipe was clarified.Taking the drill pipe as thick-walled cylinder,the stress of internal and external compressed was solved with the Lame equation.The friction torque of drill pipe outer surface was calculated with cylinder torsion methods.Considering the deformation of drill pipe,the clamping force calculation formula of on/off slip of continuous-circulation system was given.Analysis of an example has showed that the clamping force was 19MPa when the 5″or 51/2″drill pipe was used,and the thick-walled drill pipe should be used to ensure safety,and the length of on/off slip could be increased to decrease the clamping force,which could be used to guide the design of on/off slip.
出处
《钻采工艺》
CAS
北大核心
2009年第6期72-74,81,共4页
Drilling & Production Technology
基金
国家自然科学基金项目"基于钻井系统动力学的井眼轨迹预测理论及控制方法研究"(编号:50474040)
中国石油化工集团公司先导性项目"钻柱连续循环系统技术研究"(编号:P07044)
关键词
连续循环系统
上卸扣卡瓦
卡紧力
钻杆
分析
continuous-circulation system,on/off slip,clamping force,drill pipe,analysis
