Drill pipe handling apparatus having improved pipe gripping mechanism

摘要

In a drill pipe handling apparatus, a pipe gripping mechanism comprises three pipe-gripping jaws arranged to grip a pipe at locations adjacent the apices of a triangle containing the axis of the pipe. A first pipe gripping jaw is connectible to a first pivoted arm at any selected one of a set of plural distances from the pivot axis of the first arm and connected to the first arm at one of those plural distances, and a second jaw is connectible to the second arm at any selected one of the same set of plural distances from the pivot axis of the second arm and connected to the second arm at the same one of those plural distances at which the first jaw is connected to the first arm. Because the same first and second jaws are connectible to the arms at plural distances from the pivot axes, the same jaws can accommodate a wide range of pipe diameters.

主权项

1. A drill pipe handling apparatus comprising:
a pipe gripping mechanism, said pipe gripping mechanism comprising: a support frame; first and second arms connected to said support frame and movable relative to said support frame respectively about first and second pivot axes; a first actuator connected to said first arm and said support frame for moving said first arm about said first pivot axis; a second actuator connected to said second arm and said support frame for moving said second arm about said second pivot axis; a first jaw connectible to said first arm at any selected one of plural distances from said first pivot axis and connected to said first arm at one of said plural distances; a second jaw connectible to said second arm at any selected one of said plural distances from said second pivot axis and connected to said second arm at said one of said plural distances; and a third jaw connected to said support frame; wherein said first and second laws are connected to said first and second arms at equal distances from the pivot axes of the respective arms, and the first, second and third jaws are positioned in relation to one another so that a cylindrical pipe within a range of pipe diameters can be gripped by contact, by said first, second and third jaws, with the exterior surface of said cylindrical pipe respectively at locations adjacent the three apices of a triangle containing the pipe axis, said ranges of pipe diameters being different for each of said plural distance; and wherein said third jaw is movable along a line extending between said first and second jaws.