PACKER Russian patent published in 1999 - IPC

FIELD: oil production industry. SUBSTANCE: this relates to technical facilities intended for protection of production strings of wells from excessive pressure. Device has barrel, collars, lower stop and upper stop, piston with protective cone installed on pipe union, and valving unit with stop, ball and seat. Device is provided with fixing member and bush with seating recess. Ball is located inside seating recess. Pipe union and seat are also made with seating recesses. Bush interacts with stops, its ball is fixed by this bush in seating recesses of pipe union and seat and it can go out from seating recess of seat at movement of stop under action of protective housing upon it. Aforesaid embodiment of packer increases its operating reliability and widens its functional areas. EFFECT: higher efficiency. 2 dwg