摘要
塔里木油田压力系数低于1.0的超深井碳酸盐岩低压储层常发生钻井液失返性井漏,其平均井深超过6000 m,井控风险极大,除了强钻再无更好手段,往往只能提前完井。为提升超深井水平段延伸能力,研究人员研发了高强度空心玻璃微珠,可配制密度为0.93~1.07 g/cm^(3)的超低密度水基钻井液。详述了中古262-H4C井井漏失返后利用低密度水基钻井液重建井筒循环、恢复常规定向钻进的施工过程。现场钻井液密度最低降至0.98 g/cm^(3),井漏失返后多钻373 m,实现了一井钻穿两个缝洞体的地质目的,保障了该井井漏失返后钻至设计井深,开创了空心玻璃微珠超低密度钻井液在国内垂深超6000 m的超深井应用先例,为我国类似老区低压地层应用提供了技术参考。
Ultra-deep wells with pressure coefficient less than 1.0 in Tarim oilfield are generally faced with lost circulation of mud in drilling the low-pressured carbonate reservoirs.These wells,with an average depth of over 6,000 m,have high risks of well control,thus,apart from drilling with no return when lost circulation is encountered,no other better means can be used to drill the wells to the designed depths,and in many cases,the wells can only be completed before drilling to the designed depths.To extend the lengths of the horizontal sections of the ultra-deep wells,researchers have developed high strength hollow micro glass beads for formulating water-based drilling fluids with density in a range of 0.93 g/cm^(3)to 1.07 g/cm^(3).This paper describes in detail the operation process of the well Zhonggu 262-H4C in which lost circulation was encountered and a low density drilling fluid was then used to regain circulation and drilling was resumed directionally to the designed depth.In the field operation,the density of the drilling fluid was reduced to 0.98 g/cm^(3),and additional 373 m was drilled after the circulation,realizing the geological goal of one well to penetrate two fractured-vuggy bodies.This measure ensures that the well to be drilled to the designed depth after encountering lost circulation,setting a precedent of drilling an ultra-deep well with vertical depth over 6,000 m using low density drilling fluid formulated with hollow micro glass beads,and providing a technical reference for drilling low-pressured formations in old oilfields in China.
作者
张绍俊
杨成新
张宇
邵长春
李城里
喻化民
ZHANG Shaojun;YANG Chengxin;ZHANG Yu;SHAO Changchun;LI Chengli;YU Huamin(Research Institute of Oil and Gas Engineering,Tarim Oil field Branch,PetroChina,Korla,Xinjiang 841000;Engineering Technology Reseatch Institute,BHDC,Tianjin 300452;Production Capacity Construction Department of Oil and Gas Fields,Tarim Oil field Branch,PetroChina,Korla,Xinjiang 841000)
出处
《钻井液与完井液》
CAS
北大核心
2024年第4期444-450,共7页
Drilling Fluid & Completion Fluid
基金
2021年勘探与生产分公司重点盆地技术支持项目“塔里木台盆区超深井钻井技术支持”。
关键词
井漏失返
超低密度水基钻井液
空心玻璃微珠
Lost circulation
Ultra-low density water-based drilling fluid
Hollow micro glass beads
