04790394 is referenced by 29 patents and cites 11 patents.

Hydraulic drilling apparatus and method suitable for use in a variety of applications including the drilling of deep holes for oil and gas wells and the drilling of vertical, horizontal or slanted holes, drilling through both consolidated and unconsolidated formations, and cutting and removing core samples. The drill head produces a whirling mass of pressurized cutting fluid, and this whirling fluid is applied to a discharge nozzle to produce a high velocity cutting jet. The cutting action is enhanced by abrasive material in the drilling fluid. The direction of the borehole is controlled by controlling the discharge of the drilling fluid either in side jets directed radially from the distal end portion of the drill string which carries the drill head or in a plurality of forwardly directed cutting jets.

Title
Hydraulic drilling apparatus and method
Application Number
853548
Publication Number
4790394
Application Date
November 19, 1986
Publication Date
December 13, 1988
Inventor
Robert D Wilkes Jr
Berkeley
CA, US
Charles S Mackey
Bakersfield
CA, US
Sherman C May
San Francisco
CA, US
Richard R Jensen
Hacienda Heights
CA, US
Robert W Dickinson
40 Maplewood Dr., San Rafael, 94901
CA, US
Ben W O Dickinson III
2125 Broderick St., San Francisco, 94115
CA, US
Agent
Flehr Hohbach Test Albritton & Herbert
Assignee
Robert Wayne Dickinson
CA, US
Ben Wade Oakes Dickinson III
CA, US
IPC
E21B 7/18
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