长水平段水平井冲砂管柱摩阻分析及应用

针对水平井垂深浅、水平段长,因水垂比高带来作业管柱下入摩阻大,直井段油管重力不足导致冲砂作业管柱下入深度受限的问题,开展了冲砂作业管柱下入摩阻仿真模拟研究。基于水平井井眼轨迹、管柱组合结构和流体摩阻等影响因素,同时考虑冲砂作业管柱存在多变径部位的特点,结合变径部位的轴向力计算模型,建立了冲砂管柱下入摩阻的预测模型。对CP11水平井的冲砂管柱进行了下入摩阻分析。分析结果表明:采用73.0 mm+88.9 mm两种规格工具油管组合的作业管柱改变了直井段的油管重力,增大了管柱的有效推力,提高了冲砂作业管柱的下入能力。同时分析表明冲砂管柱下入速度不宜过大,管柱下入速度过大会增大管柱的流体摩阻,影响管柱下入能力。研究结果可为油田长水平段水平井作业管柱优选及现场安全施工作业提供理论指导。

Friction Analysis and Application of Sand Washing String of Long Lateral Horizontal Well

To deal with the running depth limitation of string in horizontal wells with shallow vertical depth and long lateral section due to high drag and insufficient weight of the tubing in the vertical section,the sand washing stringing running drag simulation was conducted.Considering the influencing factors including wellbore trajectory,string structure,fluid friction,and the multiple variable diameter joints on the string,combined with the axial force calculation model of the variable diameter joints,the sand washing string running drag prediction model was established.The running-in drag of the sand washing string in horizontal well CP11 was analyzed.The analysis results show that:the operation string using 73.0 mm+88.9 mm tubing changes the weight of the tubing in the vertical well section,increases the effective thrust force of the string,and improves the tubing running capacity.The analysis also indicates that the running speed should not be too high to increase the fluid friction on the string and hinder the running capacity of the string.The study can provide theoretical guidance for the optimization of the sand washing string for long lateral horizontal well and safe operations.