To address the problems of channeling through existing fractures, uneven reservoir stimulation,and limited recovery enhancement during reservoir development,the parameters of temporary plugging and directional fracturing were optimized through physical simulation experiments, and the fracture propagation laws were systematically analyzed.The effects of the mass ratio between granular temporary plugging agents (particle size: 0.31~0.34 cm) and powdery temporary plugging agents (particle size:0.10~0.18 cm), the total mass of temporary plugging agents,and the fracturing fluid injection rate on the plugging performance were investigated. Combined with large-scale physical simulation experiments, the fracture deflection characteristics were further analyzed. The results indicate a synergistic optimal relationship among the parameters.When the mass ratio of the two agents is 5∶5, the fracturing fluid injection volume is 2 000 mL, the total agent dosage is 50 g, and the injection rate is 100 mL/min,the sealing effect is optimal,with the sealed zone withstanding a stable pressure of 9.54 MPa and forming in just 81 s. In the large-scale physical model, the fracture deflection angle reached a maximum of 167.5° under this parameter combination, effectively blocking the propagation of existing fractures and forcing the fracturing fluid to expand into undeveloped areas of the reservoir. This study clarifies the optimal parameter system and fracture propagation mechanism,providing reliable experimental evidence and theoretical support for the in-situ remediation of existing fractures.

Some strategies for improvement of the key technology of testing?adjusting integrated separate injection technology have been investigated, due to much lower efficiency of conventional testing?adjusting integrated separate injection technology, which cannot accomplish layered static pressure testing. Through optimizing the string structure to improve the pressure balance during water injection, the creep of the string caused by the large displacement water injection is reduced. Design of the bridge channel of the water distributor greatly increases the flow area,reduces the interlayer interference, and further improves the testing?adjusting efficiency. Meanwhile, the pressure hole is added in the water distributor body to establish stratum?tubing pressure transfer channel, and the static pressure testing instrument is equipped for further testing of the layered static pressure. The improved technology works well in application, the deployment efficiency has been significantly improved, which takes only 5 hours to complete the deployment of 6 layers. The overpressure layer can be successfully picked out during the layered static pressure test, which provides a basis for the layered injection allocation adjustment. The adaptability of the improved technology in Bohai oilfield is significantly enhanced.