鱼骨状分支水平井井形设计优化

Design optimization for the horizontal well pattern with herringbone-like laterals

针对鱼骨状分支水平井井形设计问题,应用分段耦合模型优化确定了不同参数的设计原则,并应用正交实验方法评价了各参数的敏感性。结果表明:影响鱼骨状分支水平井产能的参数主要为分支展布参数(分支点位置、同异侧和对称性)和分支形态参数(分支长度、数目、角度和间距),其中分支形态参数对产能影响的强弱顺序依次为:分支长度、分支数目、分支角度、分支间距。鱼骨状分支水平井形态设计原则是:异侧、非对称,分支点位置靠近主井筒两端,分支数不少于2支,分支角度不小于30°,实际应用时可结合工程技术能力综合确定。方法应用于胜利油田3口鱼骨状水平井产能计算,预测误差小于3%;设计的东海平湖油气田八角亭油藏BO2井,初期产能达350 m3/d。

For the configuration design of herringbone wells,we applied a coupled multi-segment well model to determine the design principles of different parameters,and also made evaluation of the sensitivity for each parameter by orthogonal design.The results show that the factors influencing productivity of herringbone wells are mainly those of layout（location,sides and symmetry） and laterals morphology（length,number,angles and spacing）.The order of morphology parameters influencing on the production of herringbone wells is as follows： length number angle spacing for laterals.The design principles of the configuration of herringbone wells are： the laterals are on different sides and asymmetric,the laterals should be put as close as possible to the ends of the main wellbore,the number of laterals should be not least than 2,and the angle should be more than 30 degrees.The actual engineering capability should be considered in practice.With this method,three herringbone wells in the Shengli Oilfield were applied to calculate the productivity,and all the errors were less than 3%.The designed BO2 well of the Bajiaoting reservoir which was located in the Pinghu oil and gas field of East China Sea had a productivity of 350 m3/d.