焦页XX-HF井近钻头仪器“落鱼”打捞技术

Fishing of the near-bit instrument in Well Jiaoye XX-HF

涪陵页岩气二期开发过程中,为了能够及时发现地层变化,钻井平台部署的第一口井在三开井段一般使用近钻头仪器,以便及时调整井眼轨迹,提高优质页岩的钻遇率。动力钻具前面安装近钻头仪器和钻头,导致动力钻具传动轴负载增加,传动轴易发生疲劳破坏。焦页XX-HF井钻进至3971.42 m处,近钻头仪器无信号,起钻后发现动力钻具传动轴断裂,近钻头仪器和钻头落井。本井“落鱼”较短且处于水平段,“鱼头”难找,起下钻摩阻大,不易通过遇阻判断打捞工具是否接触“鱼顶”。通过对孔内情况仔细分析,制定可行的打捞方案,现场加工母锥打捞工具,最终成功将井下“落鱼”安全捞出。本井所采取的处理思路和技术措施对今后同类事故的处理具有一定的借鉴意义。

During the second stage development of Fuling Shale Gas,in order to detect formation changes in time,near-bit instruments were used in the first well planned on the drilling platform,so as to adjust the well trajectory in time and improve the intersection rate of high-quality shale.Placement of the near-bit instrument and the bit in front of the power tool will increase the load on the drive shaft of the power tool and easily lead to fatigue damage of the drive shaft.When Well Jiaoye XX-HF was drilled to 3971.42m,no signal was received from the near-bit instrument.After pulling out the drilling string,it was found that the driving shaft of the power drill tool broke off and the near-bit instrument and the bit were lost in the wellbore.The fish in this well was short and in the horizontal section;thus it was difficult to find the head of the fish.It was also difficult to determine whether the fishing tool touched the top of the fish by resistance due to the high friction.Through careful analysis of the fish,a feasible fishing plan was worked out,and the fishing box tap was processed on the spot.Finally,the fish was lifted out safely.The ideas and technical measures adopted in this well can be used for reference in dealing with similar accidents in the future.