POWERED MILLING CLAMP FOR DRILL PIPE

摘要

A powered clamp for transmitting torque to a drill pipe comprises an outer housing disposed around an axial central passage and connected to a plurality of carrier guides defining a plurality of radial slots. An inner housing defines a coaxial central passage, is rotatably connected to the outer housing, and defines a plurality of actuator slots having a spiral configuration relative to the centerline axis. A carrier is slidably disposed in each slot between the carrier guides and has a carrier pin extending into a respective one of the actuator slots. At least one powered linear actuator is connected between the outer and inner housing to selectively rotate the housings relative to one another. This rotation causes the carriers to move radially inward and outward as the carrier pins travel along the actuator slots, selectively gripping and releasing the drill pipe.

主权项

1. A powered clamp for transmitting rotational torque from a rotary drive to a drill pipe, comprising:
an outer housing adapted for releasable attachment to the rotary drive to receive torque from the rotary drive, the outer housing having an upper plate and a lower plate connected to a plurality of carrier guides disposed therebetween, the upper plate and lower plate defining a central passage along a clamp centerline axis, and the plurality of carrier guides defining a plurality of slots between one another, the slots being radially oriented with respect to the clamp centerline axis; an inner housing having a top plate and a bottom plate connected to a plurality of spacers disposed therebetween and defining a central passage along the clamp centerline axis; the inner housing being disposed between the upper and lower plates of the outer housing and rotatably connected to the outer housing to allow rotation of the inner housing about the clamp centerline axis relative to the outer housing; at least one of the upper and lower plates defining a plurality of actuator slots therein, the actuator slots having a generally spiral configuration relative to the clamp centerline axis; a plurality of carriers slidably disposed between the top and bottom plates of the inner housing and in the slots between the carrier guides, each carrier having a carrier pin extending into one of the actuator slots of the inner housing; and at least one powered linear actuator oriented substantially tangential to the clamp centerline axis and connected at a first end to the outer housing and at a second end to the inner housing; wherein selective extension and retraction of the linear actuator causes the inner housing to rotate about the clamp centerline axis relative to the outer housing, which rotation in turn causes the carriers to move radially inward and outward as the carrier pin travels along the actuator slot so as to selectively grip and release the drill pipe disposed in the central passage along the clamp centerline axis.