大规模加砂压裂完井工具冲蚀定量模拟计算及工具优化
Quantitative erosion simulation calculation and optimization for large-scale sand fracturing completion tools
伍强 1杨云徽 2刘生国 3张瑶1
作者信息
- 1. 中石化西南油气分公司石油工程技术研究院 四川德阳 618000
- 2. 中石化西南油气分公司采气二厂 四川南充 637000
- 3. 中石化西南石油工程公司井下作业分公司 四川德阳 618000
- 折叠
摘要
须家河致密砂岩气藏 120 MPa超高压、长时间大排量加砂压裂作业对管柱冲蚀影响,导致完井管柱出现变形、断裂、球座磨损、分段球不到位等问题.基于冲蚀磨损理论,选择出分段管柱中四处冲蚀严重部位,利用Ansys软件进行建模,采用动静态结合方法,计算得到了大规模加砂压裂施工管柱变径处的冲蚀程度定量值,明确了油管短节与滑套球座为冲蚀严重位置,有针对性地对冲蚀最严重位置进行了结构优化及材质优选.油管变扣短节优选Q125 钢级管材可兼顾强度及经济性;改进滑套上接头变径处台阶倒角控制在 30°以内,滑套球座顶部优化设计为弧形结构,球座采用硬质合金材质,优化改进后的滑套冲蚀程度比原结构降低 66.5%,经川东北须家河组YL15、YL171、YL6 等多口井成功应用,优化改进的压裂管柱满足了超高压加砂压裂长时间施工需求.
Abstract
The 120 MPa ultra-high-pressure,long-duration,high-displacement sand-fracturing operations in the Xujiahe tight sandstone gas reservoir have significant erosion impacts on the completion string,leading to various problems including well string deformation,fracture,ball seat wear,and improper positioning of sectional balls.Based on erosion wear theory,four severely eroded sections of the segmented string were identified.Using Ansys software,a model was developed to quantitatively evaluate the erosion extent at the diameter transition points of the large-scale sand fracturing string,employing a combination of dynamic and static methods.The short tubing joint and the sliding sleeve ball seat were identified as the most erosion-prone areas,and targeted structural optimization and material selection were conducted for these critical points.For the variable diameter short tubing joints,Q125 grade tubing was selected for its balance of strength and cost-effectiveness.The chamfer angle at the diameter transition of the sliding sleeve upper joint was controlled within 30°,the top of the sliding sleeve ball seat was redesigned with an arc shape,and the material for the ball seat was altered to hard alloy.After these optimizations and improvements,the sliding sleeve exhibited a 66.5% reduction in erosion compared to the original structure.The improved fracturing string was successfully applied in several wells in Xujiahe formation in the Northeast Sichuan,including well YL15,well YL171,and well YL6,meeting the demands of ultra-high-pressure,long-duration sand fracturing operations.
关键词
超高压/大排量/冲蚀/油管短节/滑套球座/加砂压裂/模拟计算/Ansys有限元分析Key words
ultra-high pressure/high displacement/erosion/short tubing joint/sliding sleeve ball seat/sand fracturing/simulation calculation/Ansys finite element analysis引用本文复制引用
出版年
2024
NETL
NSTL
万方数据