06367566 is referenced by 76 patents.

The system and method of the present invention permits control of down hole fluid pressures during under balanced drilling, tripping of the drill string, and well completion to substantially avoid “killing” of the well and thereby damaging the producing formations in the well bore. The system and method utilizes separate and interconnected fluid pathways for introducing a downwardly flowing hydrodynamic control fluid through one fluid pathway and for removing through the other fluid pathway a commingled fluid formed by mixing of the hydrodynamic control fluid and the well bore fluids flowing upwardly in the well bore.

Title
Down hole, hydrodynamic well control, blowout prevention
Application Number
9/253200
Publication Number
6367566 (B1)
Application Date
February 19, 1999
Publication Date
April 9, 2002
Inventor
Gilman A Hill
7128 S. Poplar La., Englewood
CO, US
Agent
Sheridan Ross PC
US
IPC
E21B 7/00
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