Analysis of drillstring dynamics using an angular rate sensor
First Claim
Patent Images
1. A downhole drilling vibration analysis method, comprising:
- drilling a borehole with a drilling assembly having at least one angular rate sensor;
determining angular positions of the drilling assembly about a circumference of the borehole while drilling downhole;
measuring instantaneous angular rates of the drilling assembly with the at least one angular rate sensor while drilling downhole;
analyzing changes of the measured instantaneous angular rates occurring at least at a plurality of the determined angular positions of the drilling assembly about the circumference of the borehole by determining, at which of the angular positions of the drilling assembly about the circumference of the borehole, decrease in the instantaneous angular rates occurs, the decrease being indicative of a sticking of the drilling assembly at the determined angular position; and
determining that torsional vibration is occurring during drilling based on the analysis.
8 Assignments
0 Petitions
Accused Products
Abstract
Downhole drilling vibration analysis uses an angular rate sensor on a drilling assembly. During drilling operations, the sensor measures the angular rate of the drilling assembly. Processing circuitry is operatively coupled to the angular rate sensor and is configured to determine whether torsional type vibrations are occurring during drilling based on the angular rate data. Drilling operations can then be modified to overcome or mitigate the torsional type vibrations.
-
Citations
49 Claims
-
1. A downhole drilling vibration analysis method, comprising:
-
drilling a borehole with a drilling assembly having at least one angular rate sensor; determining angular positions of the drilling assembly about a circumference of the borehole while drilling downhole; measuring instantaneous angular rates of the drilling assembly with the at least one angular rate sensor while drilling downhole; analyzing changes of the measured instantaneous angular rates occurring at least at a plurality of the determined angular positions of the drilling assembly about the circumference of the borehole by determining, at which of the angular positions of the drilling assembly about the circumference of the borehole, decrease in the instantaneous angular rates occurs, the decrease being indicative of a sticking of the drilling assembly at the determined angular position; and determining that torsional vibration is occurring during drilling based on the analysis. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27)
-
-
28. A downhole drilling vibration analysis method, comprising:
-
drilling a borehole with a drilling assembly having an angular rate sensor; determining rotational positions of the drilling assembly about a circumference of the borehole while drilling downhole; measuring instantaneous rotational speeds of the drilling assembly with the angular rate sensor while drilling downhole; analyzing changes of the measured instantaneous rotational speeds occurring at least at a plurality of the determined rotational positions of the drilling assembly about the circumference of the borehole by determining, at which of the determined rotational positions, decrease and/or increase in the instantaneous rotational speeds occurs, the decrease being indicative of a sticking of the drilling assembly at the determined rotational position, the increase being indicative of a slipping of the drilling assembly at the determined rotational position; and determining that torsional vibration is occurring during drilling based on the analysis.
-
-
29. A drilling assembly for drilling a borehole, the assembly comprising:
-
a drill collar disposed on a drill string; a drill bit disposed on the drill collar; a sensor element disposed on the drill collar and determining angular positions of the drilling assembly about a circumference of the borehole while drilling downhole, the sensor element including at least one angular rate sensor measuring instantaneous angular rates downhole while drilling with the drilling assembly; and processing circuitry in communication with the sensor element, the processing circuitry is configured to; analyze changes of the measured instantaneous angular rates occurring at least at a plurality of the determined angular positions of the drilling assembly about the circumference of the borehole to determine, at which of the angular positions of the drilling assembly about the circumference of the borehole, decrease in the instantaneous angular rates occurs, the decrease being indicative of a sticking of the drilling assembly at the determined angular position, and determine that torsional vibration is occurring during drilling based on the analysis. - View Dependent Claims (30, 31, 32, 33, 34, 35)
-
-
36. A downhole drilling vibration analysis method, comprising:
-
drilling a borehole with a drilling assembly having at least one angular rate sensor; determining angular positions of the drilling assembly about a circumference of the borehole while drilling downhole; measuring instantaneous angular rates of the drilling assembly with the at least one angular rate sensor while drilling downhole; analyzing changes of the measured instantaneous angular rates occurring at least at a plurality of the determined angular positions of the drilling assembly about the circumference of the borehole by determining, at which of the angular positions of the drilling assembly about the circumference of the borehole, increase in the instantaneous angular rates occurs, the increase being indicative of a slipping of the drilling assembly at the determined angular position; and determining that torsional vibration is occurring during drilling based on the analysis. - View Dependent Claims (37, 38, 39, 40, 41, 42, 43, 44, 45, 46)
-
-
47. A drilling assembly for drilling a borehole, the assembly comprising:
-
a drill collar disposed on a drill string; a drill bit disposed on the drill collar; a sensor element disposed on the drill collar and determining angular positions of the drilling assembly about a circumference of the borehole while drilling downhole, the sensor element including at least one angular rate sensor measuring instantaneous angular rates downhole while drilling with the drilling assembly; and processing circuitry in communication with the sensor element, the processing circuitry is configured to; analyze changes of the measured instantaneous angular rates occurring at least at a plurality of the determined angular positions of the drilling assembly about the circumference of the borehole to determine, at which of the angular positions of the drilling assembly about the circumference of the borehole, increase in the instantaneous angular rates occurs, the increase being indicative of a slipping of the drilling assembly at the determined angular position, and determine that torsional vibration is occurring during drilling based on the analysis. - View Dependent Claims (48, 49)
-
Specification