Gyroscopic steering tool using only a two-axis rate gyroscope and deriving the missing third axis
First Claim
Patent Images
1. A method of drilling a borehole comprising:
- (a) conveying a bottomhole assembly (BHA) on a drilling tubular into said borehole, said BHA including a drillbit for drilling said borehole;
(b) making measurements with a gyroscope having at least one sensitive axis with an angle of misalignment from orthogonality relative to an axis of rotation of said drilling tubular;
(c) determining from said measurements a toolface angle of said BHA; and
(d) drilling said borehole based on said determined toolface angle.
1 Assignment
0 Petitions
Accused Products
Abstract
A two-axis gyroscope used on a bottom hole assembly can be used for determining a rate of rotation about the rotational axis of a BHA. The method takes advantage of possible misalignment of at least one axis of the two axis gyroscope from orthogonality with respect to the rotational axis of the BHA, resulting in the misaligned gyro being sensitive to BHA rotation.
-
Citations
22 Claims
-
1. A method of drilling a borehole comprising:
-
(a) conveying a bottomhole assembly (BHA) on a drilling tubular into said borehole, said BHA including a drillbit for drilling said borehole; (b) making measurements with a gyroscope having at least one sensitive axis with an angle of misalignment from orthogonality relative to an axis of rotation of said drilling tubular; (c) determining from said measurements a toolface angle of said BHA; and (d) drilling said borehole based on said determined toolface angle. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. An apparatus for drilling a wellbore comprising:
-
(a) a bottomhole assembly (BHA) conveyed on a drilling tubular into said borehole, said BHA including a drillbit for drilling said borehole; (b) a gyroscope on said BHA, said gyroscope having at least one sensitive axis with an angle of misalignment from orthogonality with an axis of rotation of said drilling tubular; and (c) a processor which determines from measurements by said gyroscope a toolface angle of said BHA. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22)
-
Specification