06536520 is referenced by 178 patents and cites 3 patents.

A torque head for gripping tubular members, in at least some aspects, has a housing, grip mechanism secured within the housing, the grip mechanism for selectively gripping a tubular member, the grip mechanism including at least one jaw selectively movable toward and away from a portion of a tubular member within the housing, the at least one jaw having mounted thereon slip apparatus for engaging the portion of the tubular member, the slip apparatus including die apparatus movably mounted to the at least one jaw, the die apparatus movable with respect to the at least one jaw so that relative movement of the tubular with respect to the torque head is possible to the extent that the die apparatus is movable.

Title
Top drive casing system
Application Number
9/550721
Publication Number
6536520 (B1)
Application Date
April 17, 2000
Publication Date
March 25, 2003
Inventor
Gary Thompson
Katy
TX, US
Kevin Gray
Friendswood
TX, US
Jim Allen
Katy
TX, US
David Shahin
Houston
TX, US
Randy Gene Snider
Houston
TX, US
Agent
Moser Patterson & Sheridan L
US
Assignee
Weatherford Lamb
TX, US
IPC
E21B 19/16
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