渤海油田钻柱松扣关键技术

Research on key technology of drill string back-off in Bohai oilfield

钻柱松扣技术对前期采用解卡措施后仍无法有效解卡的卡钻事故具有重要意义。基于卡钻事故发生诱因及其相应的解卡机理,研究反扣钻具倒扣、正扣钻具倒扣及爆炸松扣相关技术。结果表明,若前期解卡措施难以解卡,钻柱松扣技术是最有效的解卡措施;反扣钻具倒扣技术对井深、井斜及摩阻限制较小,但倒扣失败后脱手难度大;正扣钻具倒扣适用于井深浅、井斜和摩阻小的卡钻事故,能够迅速处理海上小型平台的卡钻事故,但对于大斜度井、井眼轨迹复杂的井风险较大;爆炸松扣技术适用于井斜和狗腿度大、井眼轨迹复杂的事故井。研究结果对高效地处理卡钻事故具有重要指导意义。

The technology of drill string back off is of great significance to the failure of sticking accident after the adoption of the previous measures to remove the sticking.Based on the cause of the sticking accident and the corresponding mechanism of unfreezing,the related technologies of left-hand string back-off,right-hand string back-off and break-outing pack of dynamic have been studied.The results show that the technique of drill string back-off is the most effective method if conventional method is difficult to solve the problem.The technique of left-hand string back-off has few restrictions on well depth,deviation and friction,but it is difficult to loosen when left-hand string back-off has a failure.The right-hand string back-off is suitable for the sticking accident with low well depth,little deviation and friction.Besides that,it has advantages of quick treatments for the sticking accident of offshore platform,but it has much risk for the wells with large deviation and complex well track.The break-outing pack of dynamic is suitable for accident wells with large well deviation,dog-leg and complex well track.The research results are of important guiding significance to effectively deal with the sticking accident.