06668684 is referenced by 86 patents and cites 30 patents.

A tong as may be used for a continuous circulation system in a wellbore. The tong has a housing with a hollow interior. A plurality of spaced apart jaw assemblies reside within the housing's hollow interior for engaging a portion of a tubular to be gripped and rotated by the tong. A gear wheel is secured to the housing for rotating the housing and the jaw assemblies. The gear wheel includes a toothed outer circumference for mating with teeth of a drive shaft of a driving motor. A gear flange is movably mounted on the gear wheel such that rotation of the gear wheel does not rotate the gear flange.

Title
Tong for wellbore operations
Application Number
10/11049
Publication Number
6668684 (B2)
Application Date
December 7, 2001
Publication Date
December 30, 2003
Inventor
Jeffrey Michael Habetz
Houston
TX, US
Bernd Pietras
Wedemark
US
Steven Anthony Box
Katy
TX, US
John Timothy Allen
Katy
TX, US
Agent
Moser Patterson & Sheridan L
US
Assignee
Weatherford Lamb
TX, US
IPC
B25B 17/00
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