Mitigation of Perforation-Induced Shock Loads in Deep Slimhole Wells: Methodology and Field Applications

To address the challenges associated with excessive single-stage perforation length and high shock loads during perforation operations, a delayed initiation system was designed and implemented based on pyrotechnic delay mechanisms, capable of enabling up to 4-stage precision-delayed perforation. By reducing the explosive charge per stage and shortening detonation intervals, this system effectively attenuates instantaneous shock loads. To address post-perforation misfire issues attributed to structural instability, experimental evaluations were performed to assess the effects of tube wall thickness (1.2mm versus 1.5mm) and connection methodologies (screw fastening versus hybrid screw-welded joints). The results indicate that adopting a 1.5mm wall thickness combined with hybrid screw-welded connections significantly enhances carrier structural integrity, thereby resolving misfires induced by displacement during dynamic loading. Field trials conducted in Wells JT1 and LX1 demonstrated respective shock loads reductions of 46.4% and 39%, coupled with significant improvements in firing reliability. The optimized system synergizes pyrotechnic delay control with mechanical robustness enhancement, establishing a novel technical framework through the integration of 1.5mm wall thickness carriers and hybrid screw-welded connections. This innovation provides a validated engineering solution for mitigating shock-induced tool failures and ensuring perforation reliability, thereby advancing safer and more efficient hydrocarbon reservoir development.