Drill pipe torque reducer and method

An apparatus for reducing torque in a drill string, comprising:

• a clamp assembly comprising a first clamp segment and a second clamp segment, the first and second clamp segments each being generally arcuate and configured to connect together so as to secure the clamp assembly around an oilfield tubular and prevent the clamp assembly from axial and rotational movement relative to the oilfield tubular,
• wherein the first and second clamp segments each include a first extension and a second extension, each of the first and second extensions having a tapered end that decreases in outer diameter as proceeding in an axial direction, so as to provide a conical guide surface, wherein the first and second clamp segments each include at least one radial protrusion and at least two recesses,
• wherein the clamp assembly further includes a plurality of lock inserts each having a tapered profile and configured to fit radially between the first clamp segment, the second clamp segment, or both and the oilfield tubular, so as to secure the clamp assembly to the oilfield tubular, wherein the lock inserts each comprises a plurality of insert segments, and wherein the first clamp segment and the second clamp segment each include a plurality of pockets on an inner surface thereof, the insert segments being configured to be positioned in the pockets between axially-extending walls of the first and second clamp segments;
• and
• an outer sleeve positioned around the clamp assembly and including at least one radial protrusion configured to fit into the at least one recess of the first and second clamp segments, and at least one recess configured to receive the at least one protrusion of the first and second clamp segments, such that multiple load-transferring interfaces are formed between shoulder surfaces of the clamp assembly and shoulder surfaces of the outer sleeve,
• wherein the outer sleeve is configured to rotate with respect to the oilfield tubular and the clamp assembly, and is prevented from axial movement relative thereto, wherein the first and second clamp segments each include a central body defining a recessed region, and wherein the outer sleeve comprises an inwardly-extending protrusion configured to be received at least partially into the recessed region, so as to retain an axial positioning of the outer sleeve relative to the clamp assembly.