旋转导向在元坝超深水平井的应用

Application of Rotary Steering to Ultra-deep Horizontal Wells in Yuanba Area

元坝长兴组储层资源丰富,是中国石化重点勘探开发区域,具有储层埋藏深、温度高、含硫化氢、多压力系统并存、复杂情况难以准确预测等特性。受地理位置和产能建设制约,布井以大斜度井和水平井为主。针对超深井储层预测精度不高,水平井轨迹难控制,摩阻扭矩大等难题,中国石化西南油气分公司引进和应用了旋转导向钻井技术,在元坝103H井成功应用,整个水平井段井眼轨迹平滑,全角变化率控制在2°/30m之内,平均机械钻速为2.25m/h,比常规钻井提速23%,摩阻低于14t。

Rich natural gas can be found in the reservoir of Changxing Formation,Yuanba area,and this reservoir becomes an important domain of exploration and development for Sinopec.Under coexistence of multiple pressure systems,it contains H2S and is characterized by deep burial depth,high temperature,and complicated subsurface conditions.So,it ’s difficult to be predicted accurately.Controlled by geographical setting and restricted by deliverability construction,the highly deviated and horizontal wells are the key well-placing styles.In this paper,a drilling technology of rotary steering is introduced by Sinopec Southwest Oil & Gas Company to solve some problems,for example not high accuracy of reservoir prediction for ultra-deep wells,difficultly controlling horizontal-well trajectory and large torque and drag.This technology was applied to YB103H well successfully.After its application,the well trajectory is smooth at the whole horizontal-well interval,the total angular change rate under 20/30m,the friction resistance less than 14t,and the average penetration rate of 2.25m/h,increased by 23% compared to conventional drilling.