07191840 is referenced by 67 patents and cites 845 patents.

A method and apparatus for holding and turning a tubular and string of tubulars, such as casing, for make-up and drilling with the tubulars are disclosed. The apparatus generally includes a spear and a clamping head, both of which are mounted to a top drive. The spear and the clamping head can be engaged to transmit torque therebetween from the top drive. In addition, an aspect of the invention provides variable height wickers positioned on slips to enable use of the slips with variable inner diameter (ID) and weight casing without deformation or rupture of the casing. Still further, a casing collar is also provided to provide reinforcement to the casing in the area of slip contact with the casing ID.

Title
Casing running and drilling system
Application Number
10/794795
Publication Number
7191840 (B2)
Application Date
March 5, 2004
Publication Date
March 20, 2007
Inventor
Carl J Wilson
Hockley
TX, US
Adrian Vuyk Jr
Houston
TX, US
Thomas F Bailey
Houston
TX, US
Bernd Georg Pietras
Wedgemark
DE
Agent
Patterson & Sheridan
Assignee
Weatherford Lamb
TX, US
IPC
E21B 7/20
E21B 19/10
E21B 19/16
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