US 3,942,833 AGranted

Running tools

OwnerRowe A. Plunkinventor

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Abstract

A running tool for setting and retrieving well devices in and from wells having a mandrel reciprocable in its axial bore and slips suspended from the mandrel for reciprocation therewith into and out of supporting engagement with a well device, the bore including a counterbore in its lower portion permitting expansion of the slips into releasing position and a reduced lower extremity for contracting said slips into supporting position. A spring, confined in the counterbore around the mandrel, constantly urges said mandrel and slips downwardly and permits relative downward movement of the tool and expansion of the slips upon setting of the well device. A latch assembly is adapted to maintain the mandrel and slips in their relative upper positions upon slow lifting of the tool and is releasable upon rapid raising of said tool due to the inertia of said mandrel and slips combining with the compression of the spring to overcome the force of the latch assembly and permit upward movement of said tool relative to said mandrel and slips and reengagement of the slips with the well device. A safety lock may be provided to hold the latch assembly inoperative and prevent the inertia of the mandrel and slips from becoming effective.

Claims4

Dependent claims

A running tool for setting and retrieving a well device comprising a tubular housing having a tapered portion at the lower end of its bore adapted to receive the upper end of said device, a mandrel reciprocable in said housing from a lower position to and above an upper position, slip means carried by said mandrel, said slip means being disposed in engagement with said tapered portion in gripping position when said mandrel is in its lower position and out of engagement with said tapered portion in release position when said mandrel is at or above said upper position, said mandrel being disposed above said upper position when tool is lowered fully, first spring means urging said mandrel toward said lower position, and latch means carried by said housing for selectively holding said mandrel in said upper position, said latch means comprising a latch portion moveable into and out of engagement with a downwardly facing shoulder on said mandrel, said latch portion being spaced below said shoulder when said mandrel is above said upper position, second spring means biasing said latch portion toward engagement with said shoulder, said second spring means having a predetermined strength sufficient to retain said latch portion in latching engagement with said shoulder upon slow upward movement of said housing whereby said housing, said mandrel, and said slip means may be moved upwardly together with said slip means latched in its upper release position, but said predetermined strength being insufficient to retain said latch portion in latching engagement with said shoulder upon rapid upward movement of said housing, whereby during said rapid upward movement, said latch portion rides outwardly over said shoulder due to the inertia of said mandrel, and said slip means is moved by said first spring means to its lower gripping position with said device.

Dependencies are inferred from the claim text.