为了解决目前水力喷砂射孔施工设计准确率较低的问题,寻找实用可靠的水力喷射力学参数设计方法,进行了水力喷射与储层岩石力学作用的机理研究.根据能量守恒原理和冲量定理,建立了水力喷砂定点射穿套管、水泥环及地层系统能量方程,推导了水力喷砂定点射穿套管、水泥环及地层各阶段临界冲击力、临界冲击速度和射孔时间等关键力学参数计算模型,据此建立了水力喷砂定点射孔工艺力学分析图版.研究结果表明,水力喷砂定点射穿套管、水泥环及地层所需能量大幅度增加,射孔时间随之增大,但冲击力和冲击速度却相应降低,降低幅度比最大值分别为5.7%和8%.分析认为,建立的水力喷砂定点射孔工艺力学图版能较好地反映水力喷砂定点射孔过程,射孔时间误差为6.8%,为水力喷砂定点射孔力学参数设计与优化、水力压裂起裂基准提供了新的力学模型和理论依据.%At present, the construction and design accuracy of hydraulic sand jet perforation is lower. To solve this problem, a prac-tical and reliable method for hydraulic jet mechanic parameter design was searched for to study mechanic mechanisms of hydraulic jet on reservoir rock. According to the principle of conservation of energy and the impulse theorem, the energy equation for the process of hydraulic sand jet oriented perforation through casing, cement sheath and formation system was established, and the model for calculat-ing key mechanical parameters (e.g. critical impact force, critical impact velocity and perforation time) in each stage of jet oriented per-foration through casing, cement sheath and formation system were derived. And accordingly, the mechanical analysis chart of hydraulic sand jet oriented perforation was plotted. It is indicated that as for hydraulic sand jet oriented perforation through casing, cement sheath and formation, the required energy is increased significantly and correspondingly perforation time extends, but impact force and impact velocity decrease with maximum amplitude of 5.7% and 8%, respectively. It is revealed that the mechanical chart of hydraulic sand jet oriented perforation established in this paper can well reflect the process of hydraulic sand jet oriented perforation and its application result is good with perforation time error of 6.8%. It provides a new mechanical model and theoretical basis for the mechanical parameter design and optimization of hydraulic sand jet oriented perforation and the fracture initiation criterion of hydraulic fracturing.
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