Application of Chemical Cutting Technique in Downhole Overhaul Operation of Bozhong Offshore Oil Block

Owing to the reasons such as casing deformation and big diameter downhole tool used in the course of downhole operation,drill pipe sticking accidents often happen.Sometimes it is needed to cut the column above the sticking point and move it out.The downhole chemical cutting technique is a new means to do such work.In the operations of downhole overhaul and well completion of BZ34-4-3 well and other four wells,the chemical cutting technique was used and it expedited workover operation greatly.The configuration and working principle of the chemical cutting technique as well as its application in BZ34-4-3 well are introduced in this paper.Compared with earlier cutting techniques,the chemical cutting technique possesses the characteristics such as precise cutting and high efficiency.