非均匀射孔控制多簇裂缝均衡扩展机制及参数优化  

Non-Uniform Perforation to Balance Multi-Cluster Fractures Propagation and Parameter Optimization

作　　者：盛茂[1] 邓超 李杰[3] 顾明哲 王天宇 田守嶒[1,2] SHENG Mao;DENG Chao;LI Jie;GU Mingzhe;WANG Tianyu;TIAN Shouceng(State Key Laboratory of Petroleum Resources and Engineering,China University of Petroleum(Beijing),Changping 102249,Bei-jing,China;Karamay Campus,China University of Petroleum(Beijing),Karamay 834000,Xinjiang,China;Production Technol-ogy Research Institute,PetroChina Xinjiang Oilfield Company,Karamay 834000,Xinjiang,China)

机构地区：[1]油气资源与工程全国重点实验室,中国石油大学(北京),北京昌平102249 [2]中国石油大学(北京)克拉玛依校区,新疆克拉玛依834000 [3]中国石油新疆油田分公司采油工艺研究院,新疆克拉玛依834000

出　　处：《新疆石油天然气》2024年第3期54-63,共10页Xinjiang Oil & Gas

基　　金：国家自然科学基金面上项目“压裂诱导应力与岩石细观非均质性共同作用的页岩微裂缝开裂机理研究”(52074315)。

摘　　要：水平井多簇射孔分段压裂已成为非常规油气藏完井改造的关键技术,然而各压裂段中部射孔簇裂缝受跟端趾端射孔簇裂缝的应力干扰作用显著、扩展阻力较大,是导致多簇裂缝非均衡扩展的主要原因之一。通过优化设计簇间非均匀布孔方式,调节各簇射孔参数,均衡簇间液量分配,削弱缝间应力干扰,促进裂缝均衡扩展。为此建立了考虑压裂段/簇间应力叠加的分段多簇裂缝扩展模型,对比分析了纺锤形布孔、坡度布孔、均匀布孔等三类布孔方式的裂缝扩展规律及其作用机制,以缝长、缝高扩展形态差异性评价裂缝扩展均衡性,优选布孔方式,设计正交试验优化非均匀布孔参数。结果表明,典型页岩油储层参数条件下,纺锤形布孔的裂缝扩展均衡性最优,其次是均匀布孔、坡度布孔。其作用机制为纺锤形布孔的端部簇射孔摩阻大于中部簇1.4~16.7倍,跟端趾端裂缝对中部裂缝的应力干扰作用被削弱,从而增加了中部簇进液量分配,相比均匀布孔,裂缝扩展均衡性提高了17.2%。而坡度布孔趾端簇孔数占比35%以上,进液量占优,达49.3%,导致其对中部簇裂缝挤压作用显著,不利于裂缝均衡扩展。优化纺锤形布孔参数表明,总孔数49个、孔径10 mm、端部簇孔数比例24.5%时,簇间裂缝扩展均衡性达到最优。研究结果有望为非常规油气多簇压裂非均匀射孔设计提供有效方法。Multi-cluster perforation staged fracturing of horizontal well has become one of the key technologies for completion and stimulation in unconventional oil and gas reservoirs.However,the fractures of the central perforation clusters in each fracturing stage are significant affected by stress interference from the fractures of heel and toe clusters,leading to substantial propagation resistance of the central cluster fractures.This is a major cause of the unbalanced propagation of multi-cluster fractures.This study optimized the design of non-uniform perforation distribution pattern between clusters to regulate the perforation parameters,balance the fluid distri-bution among clusters,mitigate the stress interference between fractures,and promote the balanced propagation of fractures.Therefore,a multi-stage,multi-cluster fracture propagation model that accounts for stress superposition between stages/clusters was established.The model was used to compare and analyze the fracture propagation patterns and mechanisms of spindle-shaped,sloped and uniform perforating patterns.The difference in fracture length and height propagation morphology was utilized to assess the equilibrium of frac-ture propagation.The perforation distribution pattern was optimized,and an orthogonal test was designed to refine the parameters of non-uniform perforation distribution pattern.The findings indicate that under typical shale oil reservoir conditions,the spindle-shaped perforation pattern achieves the best fracture propagation equilibrium,followed by uniform pattern and then the sloped pattern.The mecha-nism is that,with the spindle-shaped perforation pattern,the clusters at both ends have a perforation friction 1.4~16.7 times greater than that of the central clusters,reducing the stress interference from the heel and toe fractures on the central-cluster fractures.This results in an in-creased fluid inflow distribution in the central clusters,enhancing the fracture propagation equilibrium by 17.2%compared to the uniform pattern.Conversely,

关 键 词：非均匀射孔 裂缝均衡扩展 分段多簇压裂 射孔参数 水力压裂 

分 类 号：TE357[石油与天然气工程—油气田开发工程]