渤海I27H井φ406.4 mm大尺寸井眼对扣打捞技术

钻具落井是石油行业典型的井下事故，一般需要耗费较多的时间和人力、物力来处理，直接影响着油井的命运。通过细致的钻具探伤、检查，保证入井钻具状态良好是预防事故发生的主要手段。但是由于一些客观因素的影响，钻具落井事故仍时有发生。渤海油田某井表层φ406.4 mm井眼钻井过程中发生的底部钻具脱扣落井便是此类事故的典型。在对该井基本情况和事故发生的经过做了简单介绍的基础上，对中浅层大尺寸井眼钻具落井的打捞难点做了说明，给出了可行的打捞方案，最终成功打捞出了落井钻具。

Screwing Fishing Techniques for Large Diameter Well in Bohai

Drilling tool falling is a typical downhole accident; it will spend time, manpower and material resources for dealing. The careful drilling tool detection, inspection and good-condition of drilling tool are the main insurance to prevent the accident. However, due to some objective factors, the accident still occurs. The paper presents a typical case of I27H well in Bohai oilfield, drilling tool dropped down to the hole bottom in the drilling process of a 406.4mm well, based on the brief introduction of this well and the accident process, the difficulties of drilling tool fishing in large diameter hole in middle shallow were presented and the feasible fishing scheme was put forward with successful fish operation.