04625796 is referenced by 117 patents and cites 10 patents.

Apparatus for use during connection of a length of pipe to the upper end of a drill string, preferably in a top drive drilling arrangement, and including a back-up tool for retaining the upper end of the drill string against rotation as the added length of pipe is connected threadedly thereto. This back-up tool is mounted for movement between an active position for engaging and holding the upper end of the drill string and a laterally retracted position. A stabbing unit associated with the back-up tool acts to locate the additional length of pipe while it is connected to the string, and is mounted for movement with the back-up tool between the active and inactive positions of the latter, and also for movement relative to the back-up tool, in the active position of that tool, between an extended position for engaging and holding the additional length of pipe at a location offset laterally with respect to the back-up tool and a stabbing position locating the additional length of pipe in alignment with the back-up tool for connection to the string.

Title
Well pipe stabbing and back-up apparatus
Application Number
6/718537
Publication Number
4625796
Application Date
April 1, 1985
Publication Date
December 2, 1986
Inventor
George I Boyadjieff
Anaheim
CA, US
Agent
William P Green
Assignee
Varco International
CA, US
IPC
E21B 19/20
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