▎ 摘　　要

NOVELTY - Well drilling plugging method involves (a) preparing delayed cross-linking type polymer gel plugging slurry on a construction site, and using the slurry, (b) pumping the polymer gel leakage-stopping slurry into the drill stem to fill the whole drill stem, and waiting for the consistency of the polymer gel leakage-stopping slurry to reach a specified value, (c) preparing solidified plugging slurry in the process of waiting for the consistency of the polymer gel plugging slurry to reach a specified value, (d) When the consistency of the polymer gel leakage-stopping slurry reaches a specified value, the solidified leakage-stopping slurry is adopted to replace the polymer gel in the drill stem, and after the polymer gel is completely extruded into leakage layer, the solidified leakage-stopping slurry is continuously extruded into the leakage layer, until the leakage passage is completely blocked, and (e) leveling, lifting the pipe column to a safe well section. USE - Well drilling plugging method for malignant leakage stratum. ADVANTAGE - The solidified leakage-stopping slurry uses to squeeze the polymer gel in the tubular column, ensures the retention effect of the solidified leakage-stopping slurry in a leakage layer, and simultaneously uses two materials to ensure the blocking effect by combining the characteristics of material viscosity and high-strength solidification. DETAILED DESCRIPTION - Well drilling plugging method involves (a) preparing delayed cross-linking type polymer gel plugging slurry on a construction site, and using the slurry, (b) pumping the polymer gel leakage-stopping slurry into the drill stem to fill the whole drill stem, and waiting for the consistency of the polymer gel leakage-stopping slurry to reach a specified value, (c) preparing solidified plugging slurry in the process of waiting for the consistency of the polymer gel plugging slurry to reach a specified value, (d) When the consistency of the polymer gel leakage-stopping slurry reaches a specified value, the solidified leakage-stopping slurry is adopted to replace the polymer gel in the drill stem, and after the polymer gel is completely extruded into the leakage layer, the solidified leakage-stopping slurry is continuously extruded into the leakage layer, until the leakage passage is completely blocked, (e) leveling, lifting the pipe column to a safe well section, and waiting for setting, where the cross-linked polymer gel leakage-stopping slurry is consists of water, a polymer main agent, a cross-linking agent, a retarder and a performance regulator A, the performance regulator A is thiourea, xanthan gum, sodium carboxymethylcellulose, light calcium carbonate, heavy calcium carbonate and barium sulfate, the solidified leakage-stopping slurry consists of water, a solidified main agent, a slurry stabilizer and a performance regulator B, the dosage of each component includes 20-50 wt.% curing main agent, 0.5-3 wt.% slurry stabilizer and 0-50 wt.% performance regulator B, the curing main agent is calcium sulphoaluminate, tricalcium silicate, dicalcium silicate or slag, the slurry stabilizer is nano bentonite, nano silicon dioxide or graphene oxide, and the performance regulator B is sodium hydroxide, sodium carbonate, sodium silicate, diatomite, calcium carbonate, xanthan gum, floating beads, sodium carboxyethyl cellulose, plant fibers, walnut shells or mica sheets.