大牛地气田丛式小井眼集约化钻井技术  

An intensive drilling technique of cluster-type slim hole and its application to Daniudi gasfield,Ordos Basin

作　　者：张辉[1] Zhang Hui(Petroleum Engineering Technology Research Institute,SINOPEC North China Company,Zhengzhou,Henan 450006,China)

机构地区：[1]中国石化华北油气分公司石油工程技术研究院,河南郑州450006

出　　处：《天然气技术与经济》2020年第2期28-33,共6页Natural Gas Technology and Economy

基　　金：国家科技重大专项“低丰度致密低渗油气藏开发关键技术”(编号:2016ZX05048)。

摘　　要：为了探索国内致密低渗透气藏集约化提速降本技术,以具有代表性的鄂尔多斯盆地大牛地气田为研究对象,分析了丛式井组和简化井身结构集约化应用的可行性,提出了丛式小井眼集约化钻井技术并进行了应用评价。研究结果表明:①丛式井组节约了土地,缩短了搬迁周期,整拖式“井工厂”作业模式适用于大牛地丛式定向井组的应用;②小井眼钻头切削面积缩小了22.46%~23.53%,套管尺寸缩小了18.18%~20.78%,利于提速降本;③五刀翼PDC钻头中心部位和后排齿设计锥形齿,提高了破岩效率,1.25 g/cm3低密度水泥浆体系降低了固井施工压力5.5 MPa,保障了小井眼一次全返固井;④现场试验19口井,4个井组,固井优良率达100%,平均搬迁时间缩短了54.49%,平均钻井周期缩短了24.54%,机械钻速提高了15.04%,降低了废弃物、水泥浆和套管费用,节约了征地、钻前、搬迁等费用。结论认为,丛式小井眼集约化钻井技术能够推动大牛地气田致密低渗透气藏钻井大幅度提速降本,为国内致密气藏钻井降本增效提供了借鉴。For most tight low-permeability gas reservoirs in China,in order to develop an intensive technology for improving rate of penetration(ROP)and reducing cost,this study analyzed the feasibility of one intensive application of cluster well group and simplified hole structure by taking Daniudi gasfield in Ordos Basin as an objective.In addition,an intensive drilling technique of cluster-type slim hole was put forward and evaluated.Results show that(1)an application of cluster well group can save land acquisition and shorten moving cycle,and an operation mode of integral-trailing"factory like"is applicable to this cluster-type direction well group in Daniudi gasfield;(2)the cutting area of slim-hole bit and the casing size are reduced by 22.46%-23.53%and 18.18%-20.78%,respectively,conducive to ROP improvement and cost reduction;(3)according to the design,there are cone teeth in central position and back row of five-blade PDC bit,which may increase rock-breaking efficiency.An introduction of low-density(1.25 g/cm3)slurry system decreases cementing pressure by 5.5 MPa,so as to ensure one-trip upward cementing of slim hole;and(4)it was tested on site in 19 wells of 4 well groups.The excellent cementing ratio is 100%,the moving time and drilling cycle are individually shortened by 54.49%and 24.54%on average,and the ROP is increased by 15.04%.What's more,the expenses in waste,slurry and casing are reduced,and the expenses in land acquisition,pre-drilling,and moving are also cut down.In conclusion,this intensive drilling technique of cluster-type slim hole may not only remarkably promote ROP improvement and cost reduction for these tight low-permeability gas reservoirs in Daniudi gasfield,but also provide important reference on reduc ing drilling cost and improving efficiency for those similar tight gas reservoirs in China.

关 键 词：鄂尔多斯盆地 大牛地气田 致密低渗透气藏 提速降本 小井眼 丛式井 整拖式作业模式 五刀翼 

分 类 号：TE247[石油与天然气工程—油气井工程]