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

FIELD: oil production, particularly for temporary well bore plugging during well repair.

SUBSTANCE: bridge plug comprises mandrel with radial orifices formed in lower mandrel part and end cap having inner closed groove. The mandrel is provided with fingers arranged over radial orifices. Annular groove is created in outer mandrel surface. Annular projection is made in upper part of inner mandrel surface. Annular notches are formed on outer surface of annular groove. Sealing member is installed on outer mandrel surface between lower and upper rests. End cap top is provided with additional conical member having additional slips cooperating with lover rest and formed so that the slips may perform radial displacement outwards as additional conical member approaches lower rest. Radial channels for mandrel finger receiving are created in inner surface of additional conical member so that the radial channels are not aligned with additional slips. Lower rest may be displaced with respect to the mandrel and is fixed relatively it by breakable member. The lower rest may cooperate with mandrel fingers during bridge plug removal from well. Cone installed in annular mandrel groove and connected to slips, as well as sealing member location fixer are arranged over upper rest. Sealing member location fixer is made as spring washer cooperating with annular notches of annular mandrel groove. Location fixer is pressed with mounting fixer from above. The mounting fixer is screwed on conical member. Setting tool body may cooperate with conical member and has rod connected to end cap by means of breakable member. Main slips and additional slips are correspondingly secured with conical member and additional conical member by means of dovetail connection and with upper and lower rest ends by means of T-connections. Removable unit is made as hollow cylinder provided with guiding annular ledge in upper part thereof and with annular groove formed below the annular ledge and cooperating with annular mandrel projection. The removable unit is fixed with respect to the mandrel by means of split member. Balls are installed in radial mandrel orifices so that the balls cooperate with inner closed groove of end cap on the outside and with removable unit on the inside thereof.

EFFECT: increased packing and unpacking reliability and extended operational capabilities.

3 dwg