Apparatus for tubular drill string making or breaking

Abstract

An apparatus for tubular drill string making or breaking including top wrench assembly, bottom wrench assembly, support structure, and control device. The top wrench assembly includes two top wrench bracket assemblies, top pair of movable gripping arms, top arm actuator, and top wrench camming actuator. The arm actuator allows the gripping arms to be closed or opened around the outer circumference of the pipe section, allowing top wrench assembly to engage differing casing sizes. The bottom wrench assembly includes two bottom wrench bracket assemblies, bottom pair of movable gripping arms, and bottom arm actuator. The bottom arm actuator allows the gripping arms to be closed or opened. The top wrench assembly is directly mounted on top of the bottom wrench assembly to allow relative rotation of the drill pipe section therewith. Once a pair of rollers is rotated by a hydraulic motor in the top wrench, or a pair of stationary rollers in the bottom wrench are both engaging with outer surface of the drilling string, the rollers automatically and naturally centralize or align a die insert to the most desirable central position. At this point the maximum number of die insert teeth evenly bite into the outer surface of the drill string.

1 . An apparatus for making or breaking a tubular drill string, having a wrenching mechanism integrated with a rotating mechanism, comprising:
 a first wrench assembly ( 10 ) including   a first bracket means ( 12 ) for carrying a die insert ( 54 );   actuating means ( 57 ) for actuating the die insert ( 54 ) within the first bracket means ( 12 ) to position the die insert relative to a pipe section ( 2 ) during a drill string making process; and   a pair of rotatably driven rollers ( 55 ) mounted rotatably on the first bracket means ( 12 ), wherein the die insert ( 54 ) is disposed on the bracket means ( 12 ) at a symmetrical center between the pair of rotatably driven rollers ( 55 ).   
   
   
       2 . The apparatus according to  claim 1 , wherein the first wrench assembly ( 10 ) further includes a pair of movable gripping arms ( 14 ) pivotally connected together, wherein a first bracket means ( 12 ) is pivotably mounted to each of the movable gripping arms ( 14 ). 
   
   
       3 . The apparatus according to  claim 2 , further comprising a camming means ( 18 ,  50 ) for rotating the first wrench assembly ( 10 ) relative to a support member around a centerline of a pipe section  2  during a drill string making process. 
   
   
       4 . The apparatus according to  claim 1 , further comprising a second wrench assembly ( 20 ) including
 a second bracket means ( 22 ) for carrying a die insert ( 64 );   actuating means ( 67 ) for actuating the die insert ( 64 ) within the second bracket means ( 22 ) to position the die insert relative to a pipe section ( 2 ) during a drill string breaking process; and   a pair of rotatably fixed rollers ( 65 ) fixedly mounted on the second bracket means ( 22 ), wherein the die insert ( 64 ) is disposed on the second bracket means ( 22 ) at a symmetrical center between the pair of rotatably fixed rollers ( 55 ).   
   
   
       5 . The apparatus according to  claim 4 , wherein the second wrench assembly ( 20 ) further includes a pair of movable gripping arms ( 24 ) pivotally connected together, wherein a second bracket means ( 22 ) is pivotably mounted to each of the movable gripping arms ( 24 ) of the second wrench assembly ( 20 ). 
   
   
       6 . The apparatus according to  claim 6 , wherein the second wrench assembly ( 20 ) embodies the support member.