METHOD OF RECOVERY OF TIGHTNESS OF A TUBING STRING OF A PRODUCTION WELL EQUIPPED WITH AN INSERT SUCKER-ROD PUMP Russian patent published in 2019 - IPC E21B47/10 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to a method of recovery of tightness of a tubing string of a production well. To restore tightness of the tubing string, the production well is stopped. Rod string with plunger of plug-in sucker-rod pump is lifted by 1.5 m. Working fluid is pumped – technical mineralized water – into tubing string until circulating from annular space appears. Portion of the adhesive composition is injected into the tubing string in amount of 1.0 m³, density of technical mineralized water is higher than density of adhesive composition. Performing cycles of gluing composition sinking through tubing string by pumping technical mineralized water into tubing string. Plunger of plunger rod pump is put into cylinder of tubing string and adhesive composition is pushed through tubing string by pumping into tubing string portions of technical mineralized water in amount of 0.25 m³. In the process of pumping by the manometer of the pump unit the pressure in the tubing string is controlled without allowing the pressure rise above the maximum allowable value, when the maximum allowable pressure of the selling pressure is reached, the pressure in the tubing string is bleached to zero, lifting the pump plunger, pumping into the tubing string a portion of industrial mineralized water with volume of 0.5 m³ to move a portion of the adhesive composition into the underlying interval of the tubing string. Cycles of gluing composition pouring with technical mineralized water are repeated till complete treatment of tubing string to plug-in sucker-rod pump, volume of pumped technical mineralized water is increased with each cycle by 0.1 m³. Rod string with plunger of plug-in sucker-rod pump is lifted by 1.5 m and service water is pumped into annular space by residues of glue composition from the tubing string to the surface. Well is left for the period of hardening of the adhesive composition, the plunger of the inserted sucker-rod pump is put into the cylinder of the tubing string and the production well is put into operation. As an adhesive composition a suspension of plugging material in a thickened liquid is used, and as the thickened liquid – water-filled gels based on polymers, or surfactants, or inorganic salts, or mineral thickeners, or hydrocarbon emulsions, as plugging material is used different-sized elastic foam material with open porosity based on urethanes, or rubber, or polymers, wherein before placing in the thickened liquid, the plugging foam material is impregnated with a composition which is capable of hardening in both aqueous and a hydrocarbon medium.

EFFECT: expansion of technological capabilities of the method implementation, as well as improvement of efficiency of tightness recovery in the tubing string and increase of the tubing string operation durability after the method implementation.

1 cl, 3 dwg