Temperature measurement at one or more cutting elements of a drill bit
Methods and systems are disclosed that use a temperature sensor integral to a drill bit while drilling. The temperature sensor is configured to measure temperature associated with a cutting element of the drill bit over time while drilling. The temperature sensor is used to generate time-series temperature data representing temperature of the cutting element of the drill bit over time while drilling. The time-series temperature data is processed to determine at least one condition of the wellbore and/or the drill bit while drilling, wherein the at least one condition relates to at least one of: i) detecting that a steering tool of the BHA of the drill bit is active and operating to control the direction of drilling, ii) detecting backwards whirling while drilling, and iii) detecting a transition between different types of reservoir rock while drilling.
1 . A method for detecting and monitoring at least one condition of a wellbore and/or drill bit while drilling, the method comprising:
drilling the wellbore with the drill bit, wherein the drill bit is instrumented with a temperature sensor configured to measure temperature associated with a cutting element of the drill bit over time while drilling;
using the temperature sensor to generate time-series temperature data representing temperature of the cutting element of the drill bit over time while drilling; and
processing the time-series temperature data to determine at least one condition of the wellbore and/or the drill bit while drilling, wherein the at least one condition relates to detecting that a steering tool of a bottom hole assembly (BHA) of the drill bit is active and operating to control the direction of drilling, which involves detecting oscillations in the time-series temperature data for one or more cutting elements of the drill bit.
2 . The method of claim 1 , wherein:
the temperature sensor comprises a thermocouple, a resistance temperature detector (RTD), thermistor, semiconductor-based temperature sensor, infrared temperature sensor, thermometer, bimetallic sensor, change-of-state sensor, silicon diode, or other type of temperature sensor.
3 . The method of claim 1 , wherein:
the temperature sensor is configured to measure temperature representative of temperature at or near a cutting surface of the cutting element.
4 . The method of claim 1 , wherein:
the processing of the temperature data is performed by a downhole system or a surface-located system.
5 . The method of claim 1 , wherein:
the detecting that a steering tool of the BHA of the drill bit is active and operating to control the direction of drilling further involves determining frequency of such oscillations in the time-series temperature data and determining whether the frequency of such oscillations corresponds to time-synchronized rotational frequency or RPM of the drill bit.
6 . The method of claim 5 , wherein:
the frequency of such oscillations is extracted by applying a Fast Fourier Transform (FFT) to the time-series temperature data.
7 . The method of claim 5 , wherein:
the frequency of such oscillations is extracted by applying a peak finding signal processing technique to the time-series temperature data.
8 . A method for detecting and monitoring at least one condition of a wellbore and/or drill bit while drilling, the method comprising:
drilling the wellbore with the drill bit, wherein the drill bit is instrumented with a temperature sensor configured to measure temperature associated with a cutting element of the drill bit over time while drilling;
using the temperature sensor to generate time-series temperature data representing temperature of the cutting element of the drill bit over time while drilling; and
processing the time-series temperature data to determine at least one condition of the wellbore and/or the drill bit while drilling, wherein the at least one condition relates to detecting backwards whirling while drilling, which involves detecting a drop in the time-series temperature data for one or more cutting elements of the drill bit together with an increase in the time-synchronized rotational speed (RPM) of the drill bit.
9 . A drilling system comprising:
a drill bit for drilling a wellbore through a formation, wherein the drill bit is instrumented with a temperature sensor configured to measure temperature associated with a cutting element of the drill bit over time while drilling; and
a processor configured to:
generate or obtain time-series temperature data representing temperature of the cutting element of the drill bit over time while drilling as measured by the temperature sensor; and
process the time-series temperature data to determine and monitor at least one condition of the wellbore and/or the drill bit while drilling, wherein the at least one condition relates to at least one of: i) detecting that a steering tool of a bottom hole assembly (BHA) of the drill bit is active and operating to control the direction of drilling, which involves detecting oscillations in the time-series temperature data for one or more cutting elements of the drill bit, and ii) detecting backwards whirling while drilling, which involves detecting a drop in the time-series temperature data for one or more cutting elements of the drill bit together with an increase in the time-synchronized rotational speed (RPM) of the drill bit.
10 . The drilling system of claim 9 , wherein:
the temperature sensor comprises a thermocouple, a resistance temperature detector (RTD), thermistor, semiconductor-based temperature sensor, infrared temperature sensor, thermometer, bimetallic sensor, change-of-state sensor, silicon diode, or other type of temperature sensor.
11 . The drilling system of claim 9 , wherein:
the temperature sensor is configured to measure temperature representative of temperature at or near a cutting surface of the cutting element.
12 . The drilling system of claim 9 , wherein:
the processor comprises a downhole processor or a surface-located processor.
13 . The drilling system of claim 9 , wherein:
the detecting that a steering tool of the BHA of the drill bit is active and operating to control the direction of drilling further involves determining frequency of such oscillations in the time-series temperature data and determining whether the frequency of such oscillations corresponds to time-synchronized rotational frequency or RPM of the drill bit.
14 . The drilling system of claim 13 , wherein:
the frequency of such oscillations is extracted by applying a Fast Fourier Transform (FFT) to the time-series temperature data.
15 . The drilling system of claim 13 , wherein:
the frequency of such oscillations is extracted by applying a peak finding signal processing technique to the time-series temperature data.
16 . The method of claim 8 , wherein:
the temperature sensor comprises a thermocouple, a resistance temperature detector (RTD), thermistor, semiconductor-based temperature sensor, infrared temperature sensor, thermometer, bimetallic sensor, change-of-state sensor, silicon diode, or other type of temperature sensor.
17 . The method of claim 8 , wherein:
the temperature sensor is configured to measure temperature representative of temperature at or near a cutting surface of the cutting element.
18 . The method of claim 8 , wherein:
the processing of the temperature data is performed by a downhole system or a surface-located system.