METHOD OF WELL DRILLING Russian patent published in 2000 - IPC

FIELD: drilling of oil wells, particularly, prevention and elimination of lost circulation in the course of well construction. SUBSTANCE: method provides for mud circulation drilling with use of mud based on water with subsequent addition of filler to it with colmatage properties. Mud is used in the form of freshly prepared suspension with 4-5-% concentration of polysaccharide containing 0.3-0.5% of caustic soda and polymerized monomer of dimethyldiallylammonium chloride in the amount of 0.2-0.4 wt.% of mud amount. Drill string assembly includes bottom collar colmatage device of hydrojet action in drilling with use of mud with colmatage properties. EFFECT: eliminated complications of well drilling process. 2 cl