Downhole tool with external housing torque transfer

Abstract

A downhole tool comprises a first connector sub coupled to an outer housing. A mandrel is disposed in the outer housing and is coupled to a mandrel. The second connector sub is slidably engaged with the outer housing so that torque loads are transferred from the first connector sub to the second connector sub through the outer housing independently of the mandrel.

What is claimed is: 
     
         1 . A downhole tool comprising:
 a first connector sub;   an outer housing coupled to the first connector sub;   a mandrel disposed in the outer housing; and   a second connector sub coupled to the mandrel and slidably engaged with the outer housing,   wherein torque loads are transferred from the first connector sub to the second connector sub through the outer housing independently of the mandrel.   
     
     
         2 . The downhole tool of  claim 1 , further comprising a jar mechanism disposed in an annulus between the outer housing and the mandrel, wherein the jar mechanism selectively restricts relative axial movement between the outer housing and the mandrel. 
     
     
         3 . The downhole tool of  claim 2 , wherein the jar mechanism further comprises:
 a seal body sealingly engaged with the mandrel;   a cone operable to sealingly engage a portion of the outer housing; and   a metering groove disposed between the seal body and the cone.   
     
     
         4 . The downhole tool of  claim 3 , wherein the cone sealingly engages a detent disposed on an inner surface of the outer housing. 
     
     
         5 . The downhole tool of  claim 1 , further comprising:
 a plurality of splines disposed on an outer surface of the second connector sub; and   a plurality of grooves disposed on an inner surface of the outer housing and engaged with the plurality of splines.   
     
     
         6 . The downhole tool of  claim 1 , further comprising a plurality of ports that provide fluid communication across a wall of the outer housing into an annulus between the outer housing and the second connector sub. 
     
     
         7 . A jar assembly comprising:
 a first connector sub;   an outer housing coupled to the first connector sub;   a mandrel disposed in the housing;   a jar mechanism disposed in an annulus between the outer housing and the mandrel, wherein the jar mechanism selectively restricts relative axial movement between the outer housing and the mandrel; and   a second connector sub coupled to the mandrel and slidably engaged with the outer housing.   
     
     
         8 . The jar assembly of  claim 7 , wherein the jar mechanism further comprises:
 a seal body sealingly engaged with the mandrel;   a cone operable to sealingly engage a portion of the outer housing; and   a metering groove disposed between the seal body and the cone.   
     
     
         9 . The jar assembly of  claim 8 , wherein the cone sealingly engages a detent disposed on an inner surface of the outer housing. 
     
     
         10 . The jar assembly of  claim 7 , further comprising:
 a plurality of splines disposed on an outer surface of the second connector sub; and   a plurality of grooves disposed on an inner surface of the outer housing and engaged with the plurality of splines.   
     
     
         11 . The jar assembly of  claim 7 , further comprising a plurality of ports that provide fluid communication across a wall of the outer housing into an annulus between the outer housing and the second connector sub. 
     
     
         12 . The jar assembly of  claim 7 , wherein the outer housing further comprises:
 a pressure body that is coupled to the first connector sub; and   a torque body that is coupled to the pressure body and slidably engaged with the second connector sub.   
     
     
         13 . The jar assembly of  claim 7 , further comprising a shoulder disposed on the mandrel, wherein the shoulder is operable to contact the outer housing when the first connector sub moves away from the second connector sub. 
     
     
         14 . The jar assembly of  claim 7 , further comprising a shoulder disposed on the second connector sub, wherein the shoulder is operable to contact the outer housing when the first connector sub is moving toward the second connector sub. 
     
     
         15 . A method of operating a downhole tool comprising:
 coupling an outer housing to a first connector sub;   coupling a mandrel to a second connector sub;   disposing the mandrel within the outer housing; and   slidably engaging the second connector sub with the outer housing so that torque loads are transferred from the first connector sub to the second connector sub through the outer housing independently of the mandrel.   
     
     
         16 . The method of  claim 15 , further comprising:
 disposing a jar mechanism in an annulus between the outer housing and the mandrel; and   operating the jar mechanism so as to selectively restrict relative axial movement between the outer housing and the mandrel.   
     
     
         17 . The method of  claim 16 , wherein the jar mechanism uses hydraulic fluid to restrict relative axial movement between the outer housing and the mandrel. 
     
     
         18 . The method of  claim 16 , wherein operating the jar mechanism further comprises:
 sealingly engaging the mandrel with a seal body disposed within the annulus between the outer housing and the mandrel; and   sealingly engaging the outer housing with a cone disposed adjacent to the seal body, wherein a metering groove restricts fluid flow between the seal body and the cone.   
     
     
         19 . The method of  claim 15 , wherein torque loads are transferred by a plurality of splines disposed on an outer surface of the second connector sub that are engaged with a plurality of grooves disposed on an inner surface of the outer housing. 
     
     
         20 . The method of  claim 15 , wherein at least a portion of the second connector sub is disposed within the outer housing.