Liner hanger running tool with contingency release

Abstract

A method of releasing a work string including a running tool from a liner hanger can include rotating the work string in one direction, then slacking off on the work string, and then rotating the work string in an opposite direction, thereby releasing the running tool from the liner hanger. A liner hanger running tool can include a tubular mandrel with an axially extending slot, an outer housing, and a shear member, the mandrel having an axial position relative to the outer housing in which the shear member is received in the slot and the shear member releasably secures the mandrel against rotation relative to the outer housing, and the mandrel having another axial position relative to the outer housing in which the shear member is not received in the slot and the shear member does not secure the mandrel against rotation relative to the outer housing.

What is claimed is: 
     
         1 . A method of releasing a work string including a running tool from a liner hanger in a subterranean well, the method comprising:
 rotating the work string in a first rotational direction;   then slacking off on the work string, thereby applying a compressive force to the running tool; and   then rotating the work string in a second rotational direction opposite to the first rotational direction, thereby releasing the running tool from the liner hanger.   
     
     
         2 . The method of  claim 1 , further comprising, prior to the rotating the work string in the first rotational direction, picking up on the work string. 
     
     
         3 . The method of  claim 1 , in which the first rotational direction is a counter-clockwise rotation of the work string at a surface of the well. 
     
     
         4 . The method of  claim 1 , in which the rotating the work string in the first rotational direction comprises shearing at least one shear member received in an axially extending slot formed on a tubular mandrel of the running tool. 
     
     
         5 . The method of  claim 1 , in which the rotating the work string in the first rotational direction comprises rotationally aligning at least one dog with an axially extending slot formed on a tubular mandrel of the running tool. 
     
     
         6 . The method of  claim 5 , in which the dog is received in a circumferentially extending slot formed on the mandrel. 
     
     
         7 . The method of  claim 5 , in which the slacking off on the work string comprises displacing the mandrel relative to the dog, thereby displacing the dog through the axially extending slot. 
     
     
         8 . The method of  claim 1 , in which the rotating the work string in the first rotational direction comprises aligning at least one shear member with a shoulder formed on a tubular mandrel of the running tool. 
     
     
         9 . The method of  claim 8 , in which the aligning comprises displacing the shear member through a circumferentially extending slot formed on the mandrel. 
     
     
         10 . The method of  claim 8 , in which the slacking off on the work string comprises shearing the shear member. 
     
     
         11 . A liner hanger running tool, comprising:
 a tubular mandrel with an axially extending first slot formed on the mandrel;   an outer housing; and   a first shear member,   the mandrel having a first axial position relative to the outer housing in which the first shear member is received in the first slot and the first shear member releasably secures the mandrel against rotation relative to the outer housing, and   the mandrel having a second axial position relative to the outer housing in which the first shear member is not received in the first slot and the first shear member does not secure the mandrel against rotation relative to the outer housing.   
     
     
         12 . The liner hanger running tool of  claim 11 , further comprising a dog that secures the mandrel against axial movement relative to the outer housing. 
     
     
         13 . The liner hanger running tool of  claim 12 , in which the dog is received in a circumferentially extending slot formed on the mandrel. 
     
     
         14 . The liner hanger running tool of  claim 13 , in which a release sleeve prevents disengagement of the dog from the circumferentially extending slot, and in which the release sleeve is configured to permit disengagement of the dog from the circumferentially extending slot in response to fluid pressure applied to an interior of the mandrel. 
     
     
         15 . The liner hanger running tool of  claim 12 , further comprising an axially extending second slot formed on the mandrel, and in which the second slot is configured to axially align with the dog in response to rotation of the mandrel relative to the outer housing. 
     
     
         16 . The liner hanger running tool of  claim 15 , further comprising a torque lock that limits relative rotation between the mandrel and the outer housing in the first axial position of the mandrel, and that does not limit relative rotation between the mandrel and the outer housing in the second axial position of the mandrel. 
     
     
         17 . The liner hanger running tool of  claim 11 , further comprising a second shear member received in a circumferentially extending slot formed on the mandrel, the second shear member releasably securing the mandrel against displacement from the first axial position to the second axial position. 
     
     
         18 . The liner hanger running tool of  claim 17 , further comprising a circumferentially extending shoulder formed on the mandrel, and in which the second shear member is rotationally alignable with the shoulder in response to rotation of the mandrel relative to the outer housing. 
     
     
         19 . The liner hanger running tool of  claim 18 , in which the second shear member is configured to permit the mandrel to displace from the first axial position to the second axial position without shear of the second shear member, when the second shear member is axially aligned with an axially extending second slot formed on the mandrel. 
     
     
         20 . The liner hanger running tool of  claim 11 , in which the first shear member is rotationally aligned with a circumferentially extending slot formed on the mandrel in the second axial position of the mandrel.