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US 4,362,211 AGranted
Locking mandrel
AssigneeOtis Engineering Corporation
InventorErnest P. Fisher, Jr.
Life of this patent
Estimating the term…
Abstract
A locking mandrel including a pumpdown piston and flow control means in which a dog expander engages a shoulder in a landing nipple and is moved to dog expanded position to lock the locking mandrel in the landing nipple and in which the locking mandrel may be released from the landing nipple by moving the body thereof either upward or downward to shift the expander from under the dogs to permit them to retract and release the landing nipple.
Claims18
A locking mandrel comprising,
- an elongated body,
- a dog carrier including a collet slidable on the body and including collet fingers having dogs on their free ends,
- first releasable means securing the collet against longitudinal movement on the body,
- a C-ring expander slidable on the body for expanding said dogs,
- said expander including shoulder means for engagement with a landing nipple shoulder and arresting movement of the expander in one direction,
- second releasable latch means securing said expander against longitudinal movement on the body, and
- a groove in said body receiving and holding said C-ring expander in dog extended position after said second latch means is released, and
- said body movable relative to said collet to a position disengaging said expander upon release of said first releasable means.
5 more elements
A locking mandrel comprising,
- an elongated body,
- a dog carrier mounted on the body for relative longitudinal movement with the body,
- radially extensible and contractable dog means supported on the dog carrier,
- first releasable latch means securing the dog carrier against longitudinal movement of the body,
- an expander slidable on the body for expanding said dog means, and
- second releasable latch means securing said expander against longitudinal movement on the body,
- said expander including shoulder means for engagement with a landing nipple shoulder and arresting movement of the expander in one direction,
- said expander movable to a position locating said expander under said dogs to position them in extended position after said second latch means has been released,
- said dog carrier and expander relatively movable to a position disengaging said dogs from said expander upon release of said first latch means.
6 more elements
Dependencies are inferred from the claim text.