新疆呼图壁储气库钻井液技术

新疆呼图壁储气库井上部井段阻卡频繁,安集海河组泥岩地层易发生剥落、掉块和散塌,三开高密度钻井液由于存在较强的水敏性泥岩污染,维护困难。为减少钻井工程中的复杂事故,采用了强抑制性钻井液体系,包括钾盐钻井液、钾盐-有机盐钻井液、钾盐-双膜屏蔽钻井完井液等,成功解决了各开次钻井液的技术难点,减少了钻井复杂事故,缩短了钻井周期,在目前开钻的10口储气库井中,顺利钻穿安集海河组6口,已完钻3口,其中发生卡钻事故1井次、井漏2井次,完钻井的平均钻井周期为137 d,而以往的勘探开发井发生卡钻15井次、井漏9井次,且阻卡频繁,平均钻井周期为195 d。总结出一系列针对性的技术措施并进行了广泛应用。

Drilling Fluid Technology of Hutubi Gas Storage in Xinjiang

In Hutubi gas storage wells, frequent pipe-stuck, collapsing, and caving are encountered in upper formations,and it is hard to maintain the high density drilling fluid because of contamination by high water-sensitivity mudstone inthe third interval. The high inhibitive capability drilling fluid systems are applied, such as potassium salt drilling fluid,potassium-organic salt drilling fluid, potassium-double membrane shield drill-in fluid systems, to reduce operation terms. Inapplication of 10 wells, 6 of which have drilled through Anjihaihe group safety, and 3 of which are finished. In these wells,there are only one time of pipe-stuck, 9 times of lost circulation, and the drilling period is 137 days, compared with the offsetwells of 15 times of pipe-stuck, 9 times of lost circulation and 195 days drilling period, satisfied result is achieved.