DOUBLE-ACTING HYDRAULIC PACKER Russian patent published in 2003 - IPC

FIELD: engineering; applicable in research and repairs of wells, particularly, packers. SUBSTANCE: packer has mandrel and packer setting units with sealing members, hydraulic cylinder, piston system of interrelated holes, relief valve with body in form of overturned sleeve accommodating guide bushing with channels in its walls and locking member. Body bottom has several through holes and several holes extending into side wall. Relief valve body has two seating places for upper and lower positions of locking member. Hydraulic cylinder is sectional, consisting of two chambers. Bottom of its first chamber serves concurrently as hydraulic cylinder stroke limiter and has through holes extending into the second chamber. Mandrel body in hydraulic cylinder second chamber has stop in form of circular cylinder. Valve-plug of lower packer setting unit additionally has locking member in form of ball. Double-acting hydraulic packer may be applicable in elimination of leaky points of production string in wells. EFFECT: higher vibration resistance of sealing members, reliability and longevity of sealing members and packer as a whole, both, with its removal from well and without its removal from well. 4 dwg