METHOD FOR RESTORING PRESSURIZATION OF CASING COLUMNS IN WELL AND DEVICE FOR REALIZATION OF SAID METHOD Russian patent published in 2006 - IPC E21B29/10 

FIELD: technology for major repairs of oil and gas wells, in particular, restoring pressurization of casing strings.

SUBSTANCE: in accordance to method, force patch body is used made of sheet of metallic alloy with shape memory effect. Body is rolled and positioned in sock made of high--strength material with pressurizing material on its external surface, temperature of force patch body is increased up to temperature exceeding reverse martensitic transformation point and then roll is partially unrolled and high-strength material with pressurizing material is pressed to casing string. For increasing temperature device is used passing through inside of patch body, providing even heating using temperature of hot gases during combustion of gunpowder heat generator or using thermal effect from screening effect of high-frequency electromagnetic field, created by impulse high-frequency emitter of electromagnetic field. Force body of patch with external diameter less than diameter of internal part of casing column is lowered into non-pressurized interval on geophysical cable. Device also includes a block of electronics with thimble locator, pressure sensors and a high precision thermometer.

EFFECT: increased reliability, lower laboriousness.

2 cl