08162059 is referenced by 62 patents and cites 1172 patents.

A heating system for a subsurface formation includes an elongated electrical conductor located in the subsurface formation. The electrical conductor extends between at least a first electrical contact and a second electrical contact. A ferromagnetic conductor at least partially surrounds and at least partially extends lengthwise around the electrical conductor. The electrical conductor, when energized with time-varying electrical current, induces sufficient electrical current flow in the ferromagnetic conductor such that the ferromagnetic conductor resistively heats to a temperature of at least about 300° C.

Title
Induction heaters used to heat subsurface formations
Application Number
12/250357
Publication Number
8162059 (B2)
Application Date
October 13, 2008
Publication Date
April 24, 2012
Inventor
Ronald M Bass
Houston
TX, US
Scott Vinh Nguyen
Houston
TX, US
Assignee
Shell Oil Company
TX, US
IPC
E21B 43/24
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