STRING DISCONNECTOR Russian patent published in 2003 - IPC

FIELD: extraction of hydrocarbons. SUBSTANCE: string disconnector is designed for connection and subsequent disconnection of string of pipes with packer placed in production or injection wells. String disconnector has shaft with shoulder, radial holes and outer sealing rings. Lower end of shaft carries enclosure with internal sealing rings and rest with shear screws. Enclosure and shaft form upper and lower chambers. On top there is placed body with upper sub and lower cylinder with internal sealing cup and collet. Locking device is positioned on shaft and at least one groove is cut in enclosure to accommodate it. Radial holes in shaft hydraulically communicate its internal space with upper and lower chambers. Enclosure also has radial holes hydraulically communicating correspondingly upper or lower chamber with space behind enclosure, it is linked to collet with the help of shear screws screwed into collet. Sliding bushing with outer locking device and sealing rings tightly insulating radial holes of shaft is put on shaft. Outer locking device comes in the form of snap ring. EFFECT: enhanced functional reliability and efficiency. 3 cl, 5 dwg