A downhole adjustable blade stabilizer is disclosed for varying the position of stabilizer blades to provide an increased ability to control the direction o f drilling. The adjustable blade stabilizer includes a plurality of blades mounted in an angled track to permit axial and radial movement of the blades. The blades are driven by a piston in response to a pressure differential created by a sufficient flow of drilling mud through the stabilizer. The stabilizer blades are retracted by a spring when the pressure differential is eliminated. A positioning piston limits blade extension to a desired position. The positioning piston moves in response to a command signal, and remains in place until a new command signal is received. By maintaining the positioning piston in a locked position, the position of the blades can be reset to the prior position after the loss of pressure differential. A measuring means is provided in association with the positioning piston to enable precise measurement of blade position.
申请公布号
CA2108916(C)
申请公布日期
2004.12.14
申请号
CA19932108916
申请日期
1993.10.21
申请人
DEWEY, CHARLES H.;UNDERWOOD, LANCE D.;JOHNSON, HAROLD D.
发明人
DEWEY, CHARLES H.;UNDERWOOD, LANCE D.;JOHNSON, HAROLD D.