储气库水平井井身结构优化技术及应用  

Optimization Technology and Application of Gas Storage Horizontal Well Structure

作　　者：张延兵 李录科 史配铭 Zhang Yanbing;Li Luke;Shi Peiming(Changqing Drilling Company of CNPC Chuanqing Drilling Engineering Co.,Ltd.,Shaanxi,710018)

机构地区：[1]中国石油集团川庆钻探工程有限公司长庆钻井总公司,陕西710018

出　　处：《当代化工研究》2022年第15期135-138,共4页Modern Chemical Research

摘　　要：长庆区域陕224区块储气库前期采用四开大尺寸井眼注采水平井施工过程存在各开次井眼尺寸大,机械钻速低,大井眼携砂困难,井壁稳定性差,井下垮塌严重,复杂故障频发,导致钻井周期及成本增加等问题。为此,在分析钻遇地质特性和工程难点,基于地层三压力剖面,确定套管必封点,将二开技术套管下深由进入石千峰组10~30m,调整为进入石千峰组地层50~100m,有效封隔漏层;利用钻速方程及岩石强度的尺寸效应理论,将原四开大尺寸井眼“一开Φ660.6mm+二开Φ444.5mm+三开Φ311.2mm+四开Φ215.9mm”优化缩小为四开小尺寸井眼“一开Φ444.5mm+二开Φ346mm+三开Φ241.3mm+四开Φ152.4mm”,从而形成了优化后井身结构,并在陕224储气库区应用完井2口,平均钻井周期120.25d,平均机械钻速5.24m/h,较优化前完成井钻井周期缩短49.79%,机械钻速提高174.74%,井身质量合格率100%,钻井过程无井下复杂、故障。实践表明,优化井身结构后达到了提高机械钻速、实现井壁稳定性、减少井下复杂故障、缩短钻井周期的目的。In the early stage of gas storage well in Shaanxi 224 block,Changqing oilfield,there are some problems in the construction of injection-production horizontal wells with four supping large holes,such as large hole size,low penetration rate,difficulty in carrying sand in large holes,poor wellbore stability,serious downhole collapse and frequent downhole tools failures,which lead to the increase of drilling cycle and cost.Therefore,after analyzing the geological characteristics and engineering difficulties encountered during drilling,Based on the III pressure profile of formation,the necessary sealing point of casing is determined,and the intermediate casing running depth in the second spudding is adjusted from 1~30m to 50~100m into Shiqianfeng Formation,which effectively seals the loss zone;According to the penetration rate equation and the size effect theory of rock strength,the original four-spud large-size hole is"the first spudφ660.6mm+the second spudφ444.5mm+the third spudφ311.2mm+the fourth spudφ215.9mm"was optimized and reduced to"the first spuddingφ444.5mm+the second spuddingφ346mm+the third spuddingφ241.3mm+the fourth spuddingφ152.4mm",thus forming an optimized wellbore structure.Two wells were completed in Shan 224 gas storage area,with an average drilling cycle of 100d and an average penetration rate of 8.43m/h,which was shorter than that of the wells completed in the previous period.There are no downhole complexity and failures during the drilling.Practice shows that the optimization of wellbore structure can improve penetration rate,achieve wellbore stability,reduce downhole failure complexity and shorten drilling cycle.

关 键 词：储气库 水平井 必封点 钻速方程 井身结构优化 

分 类 号：TE242[石油与天然气工程—油气井工程]