WELL COMPLETION METHOD Russian patent published in 2000 - IPC

FIELD: oil and gas production. SUBSTANCE: invention relates to methods for exposing productive formations in the course of drilling and perforation. Completion of well consists in that hole bored by assistance of drilling fluid, containing clay, carboxymethylcellulose, nitriletrimethylphosphonic acid, inhibitory additive (potassium chloride), crude oil, surfactant (sulfonol), and water, is fastened by casing string, after which productive formation is once more exposed by perforation with saline solution; when 300 m is left before exposure of productive formation, clay-based drilling fluid is supplemented by complex reagent containing carboxymethylcellulose, nitriletrimethylphosphonic acid, inhibitory additive (grouting Portland cement), and multifunctional surfactant. Finally fluid contains, wt %: clay 5-12, carboxymethylcellulose 0.3-0.5, nitriletrimethylphosphonic acid 0.02-0.04, Portland cement 0.05-0.07, surfactant 1.5-2, water - the balance. Saline solution contains 8-13% potassium carbonate and 0.3- 0.7% surfactant (as above). EFFECT: increased productivity of formation. 1 dwg, 3 tbl, 5 ex