Crack Extension Regular Pattern And Parameter Optimization Of Direction Perforation Fracture

China has accounted for more than 50% of the remaining reserves in low oil and gas resources. It is an important part of China’s oil and gas exploration and development.Hydraulic fracturing is one of the main measures to increase production in low permeability oil and gas wells. And hydraulic jet fracturing is a new method proposed in recent years for oil and gas accumulation stimulation. For the Daqing peripheral oilfield’s characteristics of big sand permeability differences, fast phase change in flat, narrow sand,scattered distribution, we carry out hydraulic fracture production increasing research and practical application.1.On the base of crack initiation and propagation mechanism in hydraulic aperture,establishing hydraulic drilling around the well bore stress field distribution model to determine the fracture initiation pressure and fracture initiation angle. Calculated burst pressure profile, analysis reveals that changes with depth, fracture pressure profile changes.2. Build a mathematical model of hydro-jet fracture elongation in the hole, and gives solution; Analyzed the influencing factors of fracturing drilling hole rupture location. The results show that: under crustal stress conditions of reservoir heterogeneity,,cracks always generate on the contact surface of hole and wellbore and extend along the direction of maximum horizontal stress after hydraulic drilling; Reservoir heterogeneity is a necessary condition for the formation of cracks. That means to form cracks in a position within the hole after hydraulic drilling, prerequisites must be reservoir heterogeneity, that there exists natural fractures or reservoir heterogeneity to stress.3. Stress orientation, petrol physical, sedimentary facies and hole geometry parameters were considered, and the system’s overall directional drilling fracturing parameters optimization method was given. On spot selected well test achieved better application results. The paper is of great significance for the transformation of low permeability reservoir stimulation, the establishment of effective communication between the sand and improve development results.