基于无限级滑套的水力裂缝演化特征研究  

Research on the evolution characteristics of hydraulic fractures based on infinite sliding sleeve

作　　者：缪尉杰 MIAO Weijie(Petroleum Engineering Research Institute of Southwest Oil and Gas Company,Sinopec,Sichuan Deyang 610080,China)

机构地区：[1]中国石化西南油气分公司石油工程技术研究院,四川德阳618000

出　　处：《非常规油气》2025年第2期112-119,共8页Unconventional Oil & Gas

基　　金：中国石化股份公司科技项目“川西中浅层致密砂岩气藏体积压裂关键技术研究”(P22736)。

摘　　要：无限级滑套压裂无需泵送桥塞,是增储、降本和增效的重要措施。通过建立基于水泥环张压起裂准则和地层张性破坏准则的裂缝双界面起裂模型,并在水泥环-地层交互演化模型中分析水力裂缝诱导应力的影响,对水力裂缝的演化特征进行了研究。数值模拟结果表明:单簇点滑套压裂会突破交界面导致起裂压力增加,起裂延伸后低延伸压力会增加缝宽与缝长;多簇滑套同时压裂时,靠近根部的裂缝处于分流优先通道,中部裂缝的扩展受应力干扰和导流综合控制的限制,最优裂缝间距为20~25 m、施工排量大于12 m^(3)/min时缝控体积最佳;多种工艺的压裂改造体积对比显示,多簇滑套依次压裂>多簇滑套同时压裂>多簇射孔压裂。该研究为无限级滑套分段工艺的致密气大型体积压裂提供理论基础,同时也为压裂施工工艺参数优化提供了有力保障。Infinite sliding sleeve fracturing does not require pumping bridge plugs and is an important measure to increase reserves,reduce costs,and improve efficiency.A dual interface fracture initiation model was constructed based on the tension-compression initiation criterion of the cement sheath and the tensile failure criterion of formation,and the stress induced by hydraulic fractures was considered in the cement sheath and formation interaction evolution model.Then,the evolution characteristics of hydraulic fractures were studied.The numerical simulation results show that there is an increase in fracture initiation pressure caused by the breakthrough at the interface during sliding sleeve fracturing in a single cluster,and low extension pressure would increase the width and length of the fracture after fracture initiation;the fractures near the root are in a diversion priority channel,and the expansion of the middle fractures is limited by stress interference and comprehensive control of diversion during sliding sleeves fracturing simultaneously in multiple clusters.The optimized fracture spacing is 20~25 m,and fracture controlling volume is optimal when the construction displacement is greater than 12 m~3/min.The comparison of stimulation volume by multi process shows that the sequential fracturing by multi cluster sliding sleeve > simultaneously fracturing by multi cluster sliding sleeve > multi cluster perforation fracturing,providing a theoretical basis for large-scale volume stage fracturing technology with infinite stage sliding sleeve in tight gas reservoirs,and also providing strong support for optimizing fracturing construction process parameters.

关 键 词：无限极滑套 水泥环-地层 双界面起裂 裂缝扩展 改造体积 

分 类 号：TE357[石油与天然气工程—油气田开发工程]