Patent ID: 7347273
Filing Date: 2008-03-25
Classification: E21B

Abstract:
1. A downhole packing device for use in a bottom hole assembly comprising an anchor device comprising a hollow cylindrical mandrel having a lower end and an upper end having a cone; a J-slot sub engaging the lower end of the mandrel, said sub defining a patterned slot having a running position, a pre-set position, a set position, and a retrieving position; a slip assembly comprising i. a lower housing having an upper end comprising a slip cage and a lower end comprising a bearing, concentrically disposed around the J-slot sub; ii. means for frictionally engaging the production tubina; iii. at least one pin disposed between the lower housing and the J-slot sub, which pin engages the slot defined by the J-slot sub; and iv. at least two slip arms each having an upper end and lower end, wherein the lower end is retained by the slip cage and the upper end comprises a tubing engaging slip, said slip arms moveable between a retracted position and an extended position wherein each said slip is disposed to slide over the cone when the slip assembly is actuated; wherein the mandrel and J-slot sub are moveable relative to the slip assembly between a running position where the pin is located in the running position in the slot and the slip arms are in the retracted position, a set position where the pin is located in the set position in the slot and the slips arms are in the extended position, a pre-set position intermediate the running position and the set position, and a retrieving position where the pin is located in the retrieving position in the slot and the slips arms are retracted; and wherein the anchor may move between the running, set and extended positions by lifting and dropping the J-slot sub relative to the pin; said packing device comprising: (a) a tubular mandrel having exterior ratchet pawls and a plurality of collet fingers having an enlarged end; (b) an upper housing comprising a top sub, a ratchet sub and a ratchet ring, said upper housing axially moveable relative to the mandrel, wherein said upper housing defines a plurality of openings for accepting shear screws affixed to the mandrel; (c) a deformable resilient seal concentrically disposed around the mandrel, below the upper housing; (d) a lower housing disposed below the seal comprising a release sub having an internal shoulder defining a collet trap which engages the collet finger ends; (e) a collet locking tube concentrically disposed within the mandrel, and moveable between a first locking position which traps the collet fingers in the collet trap, and a second release position, said collet locking tube having interior ratchet teeth; (f) wherein the upper housing is moveable between a first extended position where the upper housing does not bear on the seal and the shear screws are intact, and a second seal position, where the upper housing bears on the seal, deforming the seal radially outwards, and the shear screws are not intact; (g) and wherein the mandrel pawls and the ratchet sub and ratchet ring cooperate to maintain the upper housing in the seal position as long as the collet fingers are trapped in the collet trap.