Patent · US Expired

Steerable bit assembly and methods

US7287604B2 · kind B2 · utility

63Cited by
8References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 10, 2004
Grant dateOct 30, 2007
Priority date
Expiry dateJul 12, 2025

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B17/1014
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A drilling system includes a steerable bottomhole assembly (BHA) having a steering unit and a control unit that provide dynamic control of drill bit orientation or tilt. Exemplary steering units can adjust bit orientation at a rate that approaches or exceeds the rotational speed of the drill string or drill bit, can include a dynamically adjustable articulated joint having a plurality of elements that deform in response to an excitation signal, can include adjustable independently rotatable rings for selectively tilting the bit, and/or can include a plurality of selectively extensible force pads. The force pads are actuated by a shape change material that deforms in response to an excitation signal. A method of directional drilling includes continuously cycling the position of the steering unit based upon the rotational speed of the drill string and/or drill bit and with reference to an external reference point.

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