Apparatus for gripping a down hole tubular for use in a drilling machine

Abstract

An apparatus for gripping a down hole tubular includes a body element defining a central cavity along a longitudinal axis. Disposed within the body element is at least one engaging member. In one aspect, the engaging member has an upper gripping element and a lower gripping element. The gripping elements are designed to be movable with respect to one another. A rod is pivotally attached to the engaging member. The rod moves the engaging member radially inward or outward with respect to the longitudinal axis of the central cavity. In one embodiment, a slewing device is coupled to one end of the body element. The slewing device is moveable with respect to the body element along the longitudinal axis. The rod includes a first end and a second end. The first end is slidably and rotatably connected to the stewing device, such that the first end is radially moveable relative to the longitudinal axis as the stewing device is moved along the longitudinal axis from a first position to a second position. An engaging member is pivotally connected to the second end of the rod.

1 . An apparatus for gripping a down hole tubular for support and rotation, said apparatus comprising:
 a body element defining a central cavity having a longitudinal axis;   at least one engaging member comprising an upper gripping element and a lower gripping element disposed within said cavity of said body element, wherein said upper gripping element is moveable relative to said lower gripping element; and   at least one rod comprising a first end and second end, wherein said second end of said at least one rod is pivotably secured to said at least one engaging member, wherein said at least one rod is moveable between at least first and second positions, wherein said at least one engaging member is radially moveable inwardly from an non-engaging position to an engaging position relative to said longitudinal axis as said at least one rod is moved between said first and second positions.   
   
   
       2 . The apparatus of  claim 1 , wherein said at least one engaging member comprises a guide portion. 
   
   
       3 . The apparatus of  claim 2 , wherein said body element comprises a track, wherein said guide portion of said at least one engaging member is disposed within said track. 
   
   
       4 . The apparatus of  claim 1 , wherein said second end of said at least one rod is pivotably engaged to said upper gripping element. 
   
   
       5 . The apparatus of  claim 4 , wherein said lower gripping element is reciprocably coupled to said upper gripping element. 
   
   
       6 . The apparatus of  claim 5  further comprising a biasing element disposed between said upper and lower gripping elements. 
   
   
       7 . The apparatus of  claim 1 , wherein said second end of said at least one rod is pivotably secured to said lower gripping element. 
   
   
       8 . The apparatus of  claim 7 , wherein said upper gripping element has an opening extending therethrough, where said at least one rod is disposed through said opening of said upper gripping element. 
   
   
       9 . The apparatus of  claim 8 , wherein said upper gripping element is movable from a first position to a second position relative to said rod as said at least one engaging member is moved from said non-engaging position to said engaging position, wherein said upper gripping element is disposed further from said first end of said at least one rod when in said first position than said second position. 
   
   
       10 . The apparatus of  claim 9 , further comprising a biasing element biasing said upper gripping element towards said lower gripping element. 
   
   
       11 . The apparatus of  claim 1 , wherein said body element defines a upper end configured for engagement with a top head drive unit, said upper end defining a central passageway into said central cavity. 
   
   
       12 . The apparatus of  claim 11 , wherein said upper end engages a coupler. 
   
   
       13 . The apparatus tubular of  claim 12 , wherein said coupler is shaped and configured to mate with a down hole tubular in said central cavity. 
   
   
       14 . An apparatus for gripping a down hole tubular for support and rotation, said apparatus comprising:
 a body element defining a central cavity having a longitudinal axis;   a slewing device coupled to one end of said body element, said slewing device moveable with respect to said body element along said longitudinal axis;   at least one rod comprising a first end and second end, wherein said first end of said at least one rod is slidably and rotatably connected to said slewing device, wherein said first end of said at least one rod is radially moveable relative to said longitudinal axis as said slewing device is moved along said longitudinal axis from a first position to a second position; and   at least one engaging member pivotally connected to said second end of said at least one rod.   
   
   
       15 . The apparatus of  claim 14 , wherein said first end of said at least one rod is further from said longitudinal axis when in said first position than when in said second position. 
   
   
       16 . The apparatus of  claim 15 , wherein said at least one engaging member comprises an upper gripping element and a lower gripping element, said at least one engaging member having a non-engaging and engaging position, wherein said non-engaging position corresponds with said first position of said at least one rod, and said engaging position corresponds with said second position of said at least one rod. 
   
   
       17 . A method for gripping a down hole tubular for support and rotation, said method comprising:
 providing a body element defining a central cavity and at least one rod, having first and second ends, said second end pivotably secured to an engaging member, wherein said engaging member comprises a upper gripping element and a lower gripping element, disposed within said body element;   inserting said down hole tubular within said body element;   lowering said at least one rod to lower said engaging member;   displacing said upper gripping element and said lower gripping element; and   engaging said down hole tubular with said engaging member.   
   
   
       18 . The method of  claim 17 , wherein said displacing said upper gripping element and said lower gripping element further comprises biasing said upper gripping member towards said lower gripping member. 
   
   
       19 . The method of  claim 17 , wherein said displacing said upper gripping element and said lower gripping element further comprises biasing said lower gripping member away from said upper gripping member. 
   
   
       20 . A method for gripping a down hole tubular for support and rotation, said method comprising:
 providing a body element defining a central cavity having a longitudinal axis and at least one rod, having first and second ends, said first end slidably coupled to a slewing device, and said second end pivotably coupled to an engaging member, wherein said at least one rod is disposed within said body element;   inserting said down hole tubular within said body element;   lowering said slewing device from a first position to a second position;   radially displacing said first end of said at least one rod from a position farther from said longitudinal axis when said slewing device is in said first position, to a position closer to said longitudinal axis when said slewing device is in said second position;   lowering said at least one rod; and   engaging said down hole tubular with said engaging member when said slewing device is in said second position.