连续管在水平井井筒中的力学模拟试验系统

摘要

To have a better understanding of the downhole mechanical behavior of coiled tubing ( CT), the downhole mechanical experimental study of CT was conducted by means of the full shaft section model in light of different well bore structures. The test considered the design of similar principles and phenomenal observation, made an initial adoption of steel wire to simulate CT and used organic glass tube to simulate the shaft. The manual logging and the computer data collection system were to be combined to record the test data. The test findings show that the test system can completely simulate the buckling, buckling deadlock, wellhead yielding and buckling removal of CT in the shaft. Within the range of the capacity of test bench only planar sine buckling occurs with the bending section of shaft and no spiral buckling takes place. The axial force of head end is first released in the process of buckling removal. When the axial force of head end is less than or equivalent to that of tail end, the axial force of tail end will be released synchronically with the further release of the axial force of head end.%为了更好地了解连续管在井下的力学行为，针对不同的井身结构并考虑水平井在内的全井段模型，开展了连续管井下力学试验研究。试验考虑相似原理设计和现象观察，初步采用钢丝模拟连续管，用有机玻璃管模拟井筒。拟采用人工记录和计算机数据采集系统相结合的方法记录试验数据。试验结果表明，试验系统能够较完整地模拟连续管在井筒内的屈曲、屈曲锁死、井口屈服和解除屈曲；在试验台架能力范围内，井筒的弯曲段部分仅发生平面正弦屈曲，不发生螺旋屈曲；解除屈曲过程首先释放首端轴向力，直到首端轴向力小于等于末端轴向力时，随着首端轴向力的进一步释放，末端轴向力才同步释放。