Using Rotary Steerable System Drilling Tool Based on Dogleg Severity

Abstract

Various implementations directed to using a rotary steerable system (RSS) drilling tool based on dogleg severity are provided. In one implementation, a method may include receiving a predetermined dogleg severity for a portion of a wellbore to be drilled using the RSS drilling tool. The method may also include determining a first displacement of actuators of the RSS drilling tool from a housing of the RSS drilling tool based on the predetermined dogleg severity. The method may further include activating the actuators based on the first displacement. The method may additionally include receiving displacement data from position sensors disposed in the RSS drilling tool during drilling of the portion of the wellbore, where the displacement data corresponds to a second displacement of the actuators from the housing. The method may also include activating the actuators based on the displacement data.

What is claimed is: 
     
         1 . A method for controlling dogleg severity for a portion of a wellbore using a rotary steerable system (RSS) drilling tool disposed in the wellbore, comprising:
 receiving a predetermined dogleg severity for the portion of the wellbore to be drilled using the RSS drilling tool;   determining at least a first displacement of one or more actuators of the RSS drilling tool from a housing of the RSS drilling tool based on the predetermined dogleg severity;   activating the one or more actuators based on at least the first displacement;   receiving displacement data from one or more position sensors disposed in the RSS drilling tool during drilling of the portion of the wellbore, wherein the displacement data corresponds to at least a second displacement of the one or more actuators from the housing;   activating the one or more actuators based on the displacement data.   
     
     
         2 . The method of  claim 1 , wherein determining at least the first displacement of the one or more actuators comprises deriving at least the first displacement based on the three point geometry of the RSS drilling tool. 
     
     
         3 . The method of  claim 1 , wherein determining at least the first displacement of the one or more actuators comprises using a lookup table to determine a displacement value that corresponds to the predetermined dogleg severity. 
     
     
         4 . The method of  claim 1 , wherein a shaft of the RSS drilling tool is sufficiently angulated in order to drill the portion of the wellbore at the predetermined dogleg severity when the one or more actuators are positioned from the housing at a distance equal to the first displacement. 
     
     
         5 . The method of  claim 1 , wherein receiving the displacement data comprises receiving the displacement data at periodic intervals. 
     
     
         6 . The method of  claim 1 , wherein activating the one or more actuators of the RSS drilling tool based on the displacement data comprises:
 comparing the second displacement to the first displacement; and   activating the one or more actuators to position the one or more actuators from the housing at a distance equal to the first displacement if the second displacement differs from the first displacement by more than a predetermined limit.   
     
     
         7 . The method of  claim 1 , wherein activating the one or more actuators of the RSS drilling tool based on the displacement data comprises:
 determining an updated dogleg severity of the wellbore based on the second displacement;   comparing the updated dogleg severity to the predetermined dogleg severity; and   activating the one or more actuators to position the one or more actuators from the housing at a distance equal to the first displacement if the updated dogleg severity differs from the predetermined dogleg severity by more than a predetermined limit.   
     
     
         8 . The method of  claim 1 , wherein the RSS drilling tool comprises a steering subsystem that includes one or more bearings, the one or more actuators, and a non-rotating cantilever. 
     
     
         9 . The method of  claim 1 , further comprising:
 receiving a predetermined inclination and a predetermined azimuth for the portion of the wellbore to be drilled;   determining a first toolface angle for the RSS drilling tool based on the predetermined inclination and predetermined azimuth;   determining at least the first displacement based on the predetermined dogleg severity and the first toolface angle;   activating the one or more actuators based on at least the first displacement;   receiving survey data corresponding to one or more measurements of the Earth's gravitation vector from one or more accelerometers of the RSS drilling tool;   determining a second toolface angle for the RSS drilling tool based on the survey data;   activating the one or more actuators based on the second toolface angle.   
     
     
         10 . The method of  claim 9 , wherein activating the one or more actuators based on the second toolface angle comprises:
 comparing the second toolface angle to the first toolface angle; and   activating the one or more actuators if the second toolface angle differs from the first toolface angle by more than a predetermined limit.   
     
     
         11 . A method for controlling dogleg severity for a portion of a wellbore using a rotary steerable system (RSS) drilling tool disposed in the wellbore, comprising:
 receiving a predetermined dogleg severity for the portion of the wellbore to be drilled using the RSS drilling tool;   determining at least a first displacement of a shaft of the RSS drilling tool from a housing of the RSS drilling tool based on the predetermined dogleg severity;   activating one or more actuators of the RSS drilling tool based on at least the first displacement;   receiving displacement data from one or more position sensors disposed in the RSS drilling tool during drilling of the wellbore, wherein the displacement data corresponds to at least a second displacement of the shaft from the housing;   activating the one or more actuators of the RSS drilling tool based on the displacement data.   
     
     
         12 . The method of  claim 11 , wherein determining at least the first displacement of the one or more actuators comprises deriving at least the first displacement based on the three point geometry of the RSS drilling tool. 
     
     
         13 . The method of  claim 11 , wherein determining at least the first displacement of the one or more actuators comprises using a lookup table to determine a displacement value that corresponds to the predetermined dogleg severity. 
     
     
         14 . The method of  claim 11 , wherein receiving the displacement data comprises receiving the displacement data at periodic intervals. 
     
     
         15 . The method of  claim 11 , wherein activating the one or more actuators of the RSS drilling tool based on the displacement data comprises:
 comparing the second displacement to the first displacement; and   activating the one or more actuators to position the one or more actuators from the housing at a distance equal to the first displacement if the second displacement differs from the first displacement by more than a predetermined limit.   
     
     
         16 . The method of  claim 11 , wherein activating the one or more actuators of the RSS drilling tool based on the displacement data comprises:
 determining an updated dogleg severity of the wellbore based on the second displacement;   comparing the updated dogleg severity to the predetermined dogleg severity; and   activating the one or more actuators to position the one or more actuators from the housing at a distance equal to the first displacement if the updated dogleg severity differs from the predetermined dogleg severity by more than a predetermined limit.   
     
     
         17 . The method of  claim 11 , wherein the RSS drilling tool comprises a steering subsystem that includes one or more bearings, the one or more actuators, and a non-rotating cantilever. 
     
     
         18 . A system, comprising:
 a rotary steerable system (RSS) drilling tool disposed in a wellbore, comprising one or more actuators and one or more position sensors disposed in a housing of the RSS drilling tool;   a processor; and   a memory comprising a plurality of program instructions which, when executed by the processor, cause the processor to:
 receive a predetermined dogleg severity for a portion of the wellbore to be drilled using the RSS drilling tool; 
 determine at least a first displacement of the one or more actuators of the RSS drilling tool from the housing based on the predetermined dogleg severity; 
 activate the one or more actuators based on at least the first displacement; 
 receive displacement data from the one or more position sensors during drilling of the portion of the wellbore, wherein the displacement data corresponds to at least a second displacement of the one or more actuators from the housing; 
 activate the one or more actuators based on the displacement data. 
   
     
     
         19 . The system of  claim 18 , wherein the plurality of program instructions which, when executed by the processor, cause the processor to determine at least the first displacement of the one or more actuators comprises a plurality of program instructions which, when executed by the processor, cause the processor to derive at least the first displacement based on the three point geometry of the RSS drilling tool. 
     
     
         20 . The system of  claim 18 , wherein the RSS drilling tool further comprises a steering subsystem that includes one or more bearings, the one or more actuators, and a non-rotating cantilever.