US 8,893,779 B2Granted

Retrievable slip mechanism for downhole tool

AssigneeWeatherford/Lamb, Inc.

InventorsShawn J. Treadaway, Robert C. Stratton, James A. Rochen

Life of this patent

Estimating the term…

Loading patent…

Abstract

A downhole tool slip mechanism including a cone, cage, and slip disposed on a mandrel. The cone and cage can be move in relation to one another, and the cone may be locked into place during run-in and retrieval downhole. The cage contains slip slots contains a spring retaining finger for a spring that resides between the retention finger and the slip. This spring serves to bias the slip inward during run-in and retrieval. The slip slots have load-bearing shoulders used to engage the slip during retrieval. The slips outer surface is completely covered in wickers so that the slip can sustain greater loads when set in place. Additionally, the slip has load-bearing shoulders with an increased thickness cross-section to sustain greater loads during retrieval while minimizing slip and cage failures.

Claims21

Dependent claims

A downhole tool slip mechanism, comprising:

a cone disposed on a downhole tool;
a cage disposed on the downhole tool and defining at least one slip slot, the at least one slip slot having a closed end, an open end, and opposing inner walls extending from the closed end to the open end, at least one of the cone and cage being movable relative to the other;
at least one finger disposed on the cage and extending from the closed end to the open end of the at least one slip slot, the at least one finger having a first proximal end attached to the closed end and having a first distal end freely disposed toward the open end;
and
at least one slip disposed in the at least one slip slot and being movable between retracted and extended positions relative to the downhole tool, the at least one slip having a second proximal end and a second distal end, the at least one slip having opposing sides toward the second proximal end, a deck toward the second proximal end, and a toe toward the second distal end, the deck connecting the opposing sides and disposed between the at least one finger and the downhole tool, the deck being retained radially by the at least one finger, the opposing sides exposed in the at least one slot between the opposing inner walls and the at least one finger, the toe disposed at least radially unretained beyond the open end of the at least one slot, the opposing sides each defining a first bearing surface retained axially by the opposing inner walls of the at least one slip slot.

2 more elements

Dependencies are inferred from the claim text.