汶川地震断裂带科学钻探项目WFSD-4S孔卡钻事故处理

Treatment of Sticking Accident in WFSD-4S of Wenchuan Earthquake Fault Scientific Drilling Project

摘要:

汶川地震断裂带科学钻探项目WFSD-4S孔地层复杂，钻探施工难度大，孔内缩径、坍塌、掉块事故频发，给钻探施工带来了极大的困难。就WFSD-4S孔在孔深517 m发生的卡钻事故进行了详细的阐述，分析发生卡钻事故的原因及条件，采用了强力起拔、反钻杆、可退式打捞矛打捞、套铣等手段，最终成功处理该起卡钻事故。该起事故的经验，为同类事故的处理提供借鉴及参考。

Abstract:

The formations are extremely complicated in WFSD-4S of Wenchuan earthquake fault scientific drilling project, drilling was difficult with frequent wellbore shrinkage, collapse and block falling accidents, which brought great difficulties for the drilling construction. The sticking accident occurred at 517m depth is elaborated in detail, and the accident causes and conditions are analyzed. By means of forceful pulling, drill pipe reverse rotating, fishing by releasing spear, casing milling and some other ways, the sticking accident is smoothly processed. The treatment experience can be reference to the similar accidents.