Releasable wireline cablehead

Abstract

An apparatus for releasably connecting a wireline to a downhole tool comprises a connector having a first member adapted for connection to the downhole tool and a second member adapted for connection to the wireline. A plurality of locking elements are constrained to engage the first and second members by a moveable release member, where the plurality of locking elements maintain the first and second members in a connected position when the moveable release member is in a first locked position. An electromechanical actuator moves the moveable release member to a second released position, releasing the plurality of locking elements from engagement with the first and second members. This allows the first and second members to release the wireline from the tool.

What is claimed is:  
     
         1 . A system for use in a wellbore, comprising: 
 a. a wireline extending from a surface location to a predetermined location in the wellbore;    b. a tool string having at least one tool adapted to perform at least one downhole operation; and    c. a cable head for releasably connecting said wireline to said tool string.    
     
     
         2 . The system of  claim 1 , wherein the cable head includes: 
 i. a first member adapted for connection to the downhole tool and a second member adapted for connection to the wireline;    ii. a plurality of locking elements constrained to engage said first member and said second member by a moveable locking sleeve, said plurality of locking elements maintaining said first member and said second member in a connected position when said moveable locking sleeve is in a first position; and    iii. an actuator adapted to move said moveable locking sleeve to a second position releasing said plurality of locking elements from engagement with said first member and said second member allowing said first member and said second member to release said wireline from said tool.    
     
     
         3 . The system of  claim 2  wherein the plurality of locking elements are balls.  
     
     
         4 . The system of  claim 2  wherein the actuator includes a solenoid.  
     
     
         5 . The system of  claim 2  wherein the actuator includes a motor drive.  
     
     
         6 . The system of  claim 2  further comprising a breakable tensile link.  
     
     
         7 . The system of  claim 2  wherein the plurality of locking elements includes locking fingers.  
     
     
         8 . The system of  claim 7  wherein the locking fingers pivot about a hinge.  
     
     
         9 . The system of  claim 7  wherein the locking fingers comprise collet type elements.  
     
     
         10 . The system of  claim 2 , wherein the plurality of locking elements move inwardly when said moveable locking sleeve is moved to the second position.  
     
     
         11 . The system of  claim 1 , wherein the wireline is a multi-conductor wireline.  
     
     
         12 . The system of  claim 1 , wherein the at least one tool is a logging tool.  
     
     
         13 . The system of  claim 1 , wherein the cable head is remotely operated by a surface controller.  
     
     
         14 . An apparatus for releasably connecting a wireline to a downhole tool, comprising: 
 a. a cable head having a first member adapted for connection to the downhole tool and a second member adapted for connection to the wireline;    b. a plurality of locking elements constrained to engage said first member and said second member by a moveable locking sleeve, said plurality of locking elements maintaining said first member and said second member in a connected position when said moveable locking sleeve is in a first position; and    c. an actuator adapted to move said moveable locking sleeve to a second position releasing said plurality of locking elements from engagement with said first member and said second member allowing said first member and said second member to release said wireline from said tool.    
     
     
         15 . The apparatus of  claim 14  wherein the plurality of locking elements are balls.  
     
     
         16 . The apparatus of  claim 14  wherein the actuator includes a solenoid.  
     
     
         17 . The apparatus of  claim 14  wherein the electromechanical actuator includes a motor drive.  
     
     
         18 . The apparatus of  claim 14  further comprising a breakable tensile link.  
     
     
         19 . The apparatus of  claim 14  wherein the plurality of locking elements includes locking fingers.  
     
     
         20 . The apparatus of  claim 19  wherein the locking fingers pivot about a hinge.  
     
     
         21 . The apparatus of  claim 19  wherein the locking fingers comprise collet type elements.  
     
     
         22 . The apparatus of  claim 14 , wherein the plurality of locking elements move inwardly when said moveable locking sleeve is moved to the second position.  
     
     
         23 . The apparatus of  claim 14 , wherein the wireline includes multiple conductors.  
     
     
         24 . The apparatus of  claim 14 , wherein the wireline includes at least one optical fiber.  
     
     
         25 . A method of releasably connecting a wireline to a downhole tool, comprising; 
 a. locking a first member coupled to the wireline to a second member coupled to the downhole tool by using a locking sleeve to constrain a plurality of locking elements to engage said first member and said second member when said locking sleeve is in a first position; and    b. using an actuator to move said locking sleeve from said first position to a second position releasing said plurality of locking elements from engagement with said first member and said second member for releasing said first member from said second member and releasing said wireline from said downhole tool.    
     
     
         26 . The apparatus of  claim 25  wherein the plurality of locking elements are balls.  
     
     
         27 . The apparatus of  claim 25  wherein the actuator includes a solenoid.  
     
     
         28 . The apparatus of  claim 25  wherein the actuator includes a motor drive.  
     
     
         29 . The apparatus of  claim 25  further comprising a breakable tensile link.  
     
     
         30 . The apparatus of  claim 25  wherein the plurality of locking elements includes locking fingers.  
     
     
         31 . The apparatus of  claim 30  wherein the locking fingers pivot about a hinge.  
     
     
         32 . The apparatus of  claim 30  wherein the locking fingers comprise collet type elements.  
     
     
         33 . The apparatus of  claim 25 , wherein the plurality of locking elements move inwardly when said moveable locking sleeve is moved to the second position.  
     
     
         34 . The apparatus of  claim 25 , wherein the wireline includes at least one optical fiber.