Well tool with shearable collet

A well tool apparatus for releasably latching a string of drill pipe to a string of liner in a wellbore, comprising:

• a liner hanger having a lower end configured to be secured to the string of liner, the liner hanger having an axis, the liner hanger having a set of slips, the slips being radially movable between a disengaged position to a set position in engagement with a casing string in the wellbore in response to axial movement of the slips;
• a running tool having a mandrel with an upper portion configured to be secured to the string of drill pipe;
• a latch carried by and axially movable relative to the running tool, the latch comprising a collet, the collet comprising a plurality of fingers, each of the plurality of fingers of the collet comprising an external upward-facing shoulder, the latch being radially resilient and biased to a radially expanded position, and the latch having a latched position in which the latch is latched to the slips;
• a collet cage carried by the running tool, the collet cage comprising a plurality of windows, each of the plurality of fingers of the collet protruding partially inward into a respective window of the plurality of windows;
• an inward and upward facing cam surface on the collet cage below each of the plurality of fingers of the collet;
• and
• a shear element mounted directly to the latch, the running tool configured to axially move the latch to shift the slips to the set position and the collet cage being prevented from axial movement relative to the collet while the shear element is intact, and the latch being axially movable relative to the slips to release the latch from the latched position and the collet cage being axially movable after the shear element has sheared, with upward axial movement of the collet cage relative to the collet being configured to cause the plurality of fingers of the collet to deflect radially inward, the shear element being shearable by a selected axial force applied to the latch after the slips are in the set position.

A method of manipulating well tools, comprising:

• (a) providing a running tool having a mandrel, an axially movable latch that is radially resilient and biased to a radially expanded position, and at least one shear element mounted directly to the latch;
• (b) attaching a liner hanger to a string of liner, the liner hanger having a set of slips;
• (c) mounting the mandrel and a collet cage to a running string and lowering the running tool into the liner hanger, causing the latch to snap into engagement with the slips while the shear element remains intact;
• then to set the liner hanger and release the running tool from the liner hanger, wherein the shear element while intact prevents axial movement of the collet cage relative to a collet of the running tool;
• (d) applying an axial force to the latch, which causes the latch to move relative to the mandrel to move the slips to the set position;
• and
• (e) shearing the shear element with the axial force, causing the latch to release from the slips.

A well tool apparatus, comprising:

• a running tool having an axis and configured to be carried by a running string into and out of a wellbore;
• a collet carried by the running tool, the collet having a plurality of fingers each of which has an elongated slot extending axially therein, the plurality of fingers of the collet being in a radially expanded position arranged to latch against a wellbore shoulder in the wellbore and to restrict upward movement of the running tool, the plurality of fingers of the collet being resiliently and radially movable to unlatch the running tool, and the plurality of fingers of the collet each having an external upward-facing shoulder;
• and
• a plurality of shear elements carried by the collet, each of the plurality of shear elements being mounted to one of the plurality of fingers such that at least a portion thereof is located above the upward-facing shoulder with the elongated slot extending axially downward therefrom, each of the plurality of shear elements having a head protruding radially outward from at least one of the plurality of fingers approximately to an outer extent of the upward-facing shoulder for engagement with the wellbore shoulder, wherein the plurality of shear elements restrict the plurality of fingers from moving radially to unlatch the running tool while the shear element is intact, while also being configured to shear upon application of a selected axial force, thereby freeing the plurality of fingers to move radially to unlatch the running tool.