Patent ID: 8739888
Filing Date: 2014-06-03
Classification: E21B

Abstract:
1. A casing gripper comprising: a load bearing mandrel defining a central bore cavity having a central axis and adapted to be secured to a quill of a top drive, the load bearing mandrel having external threads on a portion of the load bearing mandrel between an upper end and a lower end; a rotary to linear converter enclosing a portion of the mandrel and configured to convert rotary motion of the load bearing mandrel into linear motion by a lower portion of the converter when an upper portion of the converter is held stationary, the rotary to linear converter having: a grapple coupled to the lower portion of the converter and extending along a portion of the load bearing mandrel for axial movement therewith, wherein gripping the wrench by the grabber and rotating the quill causes the nut and grapples to move axially; and the grapple being radially moveable to grip a casing member when moved axially in one direction and to release the casing member when moved axially in an opposite direction.