Downhole weight-on-bit control for directional drilling
Curved drilling apparatus
Method and system of trajectory prediction and control using PDC bits
Drill bit with performance-improving cutting structure
Stability enhanced drill bit and cutting structure having zones of varying wear resistance
Drill bits with predictable walk tendencies Patent #: 5937958
ApplicationNo. 470525 filed on 12/22/1999
US Classes:175/73, MEANS TRAVELING WITH TOOL TO CONSTRAIN TOOL TO BORE ALONG CURVED PATH76/108.4, Well drill175/398, Nonsymmetrical bit175/431Having a particular orientation or location
ExaminersPrimary: Neuder, William P.
Attorney, Agent or Firm
Foreign Patent References
International ClassE21B 010/46
AbstractA drill bit with dropping tendencies includes an active region, a passive region, a biased mass distribution, an uneven torque generation, and an imbalance force vector directed toward the middle of the active region. Cutting elements in the active region of the drill bit may be more aggressive than those in the passive region through manipulation of, e.g., backrake angle, blade length, cutter sizes, blade angles and bit profile. The imbalance force vector may be achieved by manipulation of bit geometric parameters such as cutter radial position, angular position, longitudinal position, and rake angle.