千米桥潜山小间隙欠平衡钻井液研究

STUDY ON THE DRILL-IN FLUID FOR SMALL CLEARANCE UNDER-BALANCED DRILLING IN QIANMIQIAO BURIED HILL, DAGANG

郑淑杰 许京国 苏秀纯 王凌梅

Zheng Shujie Xu Jingguo Su Xiuchun Wang Lingmei

大港油田钻采院材料所, 天津大港 300280

Material Dept. of Drilling and Production Inst., Dagang Oilfield

在对千米桥古潜山凝析油气藏地质特征、完钻井情况进行分析的基础上,对大港油田千米桥古潜山凝析油气藏进行了一系列的研究,包括奥陶系小间隙钻井液密度、粘度、抑制性、抗高温性、抗污染能力等研究;奥陶系小间隙井油气层保护研究;钻进过程中,奥陶系酸性物质对钻具的防腐蚀性研究。结果表明,钻井液密度小于1.0g/cm3时用油包水钻井液;封堵漏层时,采用复合堵漏剂和单封;用碱性碳酸锌和缓蚀剂进行防腐。现场应用10多口井,均取得了较好的效果。

Based on the investigations to the geology characteristics of condensate oil and gas reservoirs in the buried hill of Qianmiqiao, and analysis to the completed wells in this area, studies were carried out on the drill-in fluid used for under-balanced drilling in the small clearance holes. For example, study on such performances as density, viscosity, shale inhibition, high-temperature tolerance, contamination resistance of the drilling fluid used in the small clearance of the Ordovician system; study on formation protection in the small clearance of the Ordovician system; study on drill pipe corrosion in drilling caused by the sour materials in the Ordovician system. Study results showed that when drilling fluid density of lower than 1.0g/cm3 is demanded, water-in-oil drilling fluid should be used; when plugging the lost circulation zones, the composite plugging agent and unidirectional pressure sealing agent should be adopted. Basic zinc-carbonate and corrosion inhibitor can be used for protecting drill pipe form corrosion. These study achievements have been used in over ten wells, with good results obtained.

10.3969/j.issn.1000-7393.2002.01.011