Patent · US Expired

Adjustable stabilizer

US5318138A · kind A · utility

140Cited by
51References
35Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 23, 1992
Grant dateJun 7, 1994
Priority date
Expiry dateOct 23, 2012

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B23/042
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A downhole adjustable blade stabilizer is disclosed for varying the position of stabilizer blades to provide an increased ability to control the direction of 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 device is provided in association with the positioning piston to enable precise measurement of blade position.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.