哥伦比亚G-5井套管浮鞋浮箍落井事故分析与处理

The Analysis and Processing of Casing Float Shoe and Collar Falling Accident of Columbia G-5 Well

由长城钻探钻井一公司GW140队负责施工的G-5井位于哥伦比亚Matambo区块,山前构造地层岩性复杂,安全密度窗口较低,漏失严重,井身结构复杂,在三开钻井施工过程中,发现二开技术套管浮鞋、浮箍相继落井,造成2 500 m处套管落井事故。针对该事故提出合理的处理方案,采用过套管钻井技术成功完成三开3 800 m钻完井作业,避免填井和新侧钻。

G-5 well is constructed by GW140 drill crew of No.1 Drilling Company of GWDC and it is located in Columbia Matambo block.In this block,the piedmont configuration is complex,the density window of safe drilling fluid is narrow,the formation leakage is serious and the well structure is complex.During the third open drilling,the second open intermediate casing float shoe and collarfell in well successional and caused the casing falling accident in the position of 2500m.A reasonable treatment scheme is proposed for solving the accident and through-casing drilling technology is adopted for the 3800m third open drilling and completion.So filling well and sidetrack drilling is avoided and it can save drilling time and cost.The paper introduces the analysis and processing procedure of this accidentand proposes a new method for treating the pipe fish in the downhole.