降密度控压欠平衡钻井技术在页岩气井中的应用

Application of Lower Density and Control of Underbalanced Formation Pressure in Shale Gas Wells

控压欠平衡钻井是国外新近发展起来的一项新的钻井技术,为解决复杂地层安全钻进问题提供了一个新方案。在焦页XX-4HF井进行了降密度控压欠平衡钻井现场试验,在涪陵页岩气井首次现场应用该钻井关键工艺,解决了水平段施工中的溢漏同存难题,通过在循环、钻进、起下钻和堵漏等不同工况的控压钻井程序,有效降低了水平段井漏,取得了地层原始资料,保障了井下安全,成功完成了钻探任务。

Drilling with underbalanced formation pressure control was a drilling technology newly developed abroad,itprovided a new program for safety drilling in complex formations.The technology of lower density and control of underbalanced pressure was tested in Well Jiaoye XX-4HF,the key technology was first used in Fuling shale gas well,the problem of leakage is solved in the drilling of horizontal section.By using the program of circulating drilling,tripping and blocking of lost circulation in different conditions,the lost circulation in horizontal sections is effectively reduced and data in formation drilling are obtained,it provides safety in downhole operation and the drilling task is successfully.completed