BRIDGE PLUG Russian patent published in 2006 - IPC E21B33/12 

FIELD: oil production industry, particularly for temporary well bore sealing for isolation work performing during well operation and repair, formation investigation and fluid injection in wells.

SUBSTANCE: setting tool body provided with annular rest in lower body part is installed in air-tight manner in stem so that setting tool body may perform upward and downward axial movement and is secured by spline connection. Setting tool body performs limited axial displacement with the use of upper and lower adjusting extensions formed on outer body surface. Setting tool body is connected with setting tool rod in upper part thereof by breakable members. Upper and lower conical parts tapering one towards another are created on outer stem surface. Annular recess is made between the conical parts adapted to receive bush concentric to shaft. The bush has locating fixer made as finger cooperating with vertical grooves formed in annular recess. The vertical grooves include two short grooves and one long one located between the short grooves. In transport position finger enters right short vertical groove connected with central part of long vertical groove by upper part thereof so that finger passes into long vertical groove in working position through upper transversal groove. Left short vertical groove is connected with lower part of long vertical groove by lower part thereof through lower transversal groove. Upper end of left short vertical groove has figured groove part adapted to receive finger after body reciprocation during tool removing from stem. Figured groove part has lesser vertical dimensions in comparison with vertical dimensions of long vertical groove. Slips are installed on the bush and are composed of upper and lower dies with centrators. The dies are spring-loaded in outward direction and face outer annular extension arranged in central bush part. Upper and lower dies are provided with conical surfaces arranged in top and bottom parts thereof. In working position the conical surfaces may cooperate with upper and lower conical parts of the stem. Sealing member is composed of upper and lower self-sealing collars arranged above and below upper and lower conical parts correspondingly. The self-sealing collars are pressed by upper and lower rests. Upper self-sealing collar is adapted to restrain pressure difference in upward-downward direction. Lower self-sealing collar may restrain pressure difference in downward-upward direction. Upper and lower rests are provided with upper and lower spring-loaded valves correspondingly, which permit liquid passage outside the stem. Upper spring-loaded valve is pressed with cap fixedly connected with stem and rests upon annular groove of upper rest. Lower spring-loaded valve is pressed with cap fixedly secured with the stem and rests upon annular groove of lower rest.

EFFECT: increased reliability of plug removing and installation extended operational capabilities, possibility to use production-run fishing tool for plug removal.

2 dwg