Automatic and integrated control of bottom-hole pressure

Abstract

A method for responding to an adverse fluid event such as a fluid gain or fluid loss event includes pumping a drilling fluid through a drilling system having a drill string and into a well bore. The drilling system also includes at least two pressure control components operatively coupled to the drill string. The bottom hole pressure of the well bore may be monitored. Once a fluid loss condition or a fluid gain condition is detected, a response for each of the at least two pressure control components to the fluid loss or fluid gain condition is determined. The responses for the at least two pressure control components are prioritized, and at least one of the pressure control components are adjusted to mitigate the adverse pressure condition.

What is claimed is: 
     
         1 . A method comprising:
 pumping a drilling fluid through a drill string and into a well bore, wherein at least two pressure control components are operatively coupled to the drill string;   monitoring a bottom hole pressure of the well bore;   detecting a fluid loss condition or a fluid gain condition;   determining a response for each of the at least two pressure control components to the fluid loss or fluid gain condition;   prioritizing the responses for the at least two pressure control components; and   adjusting one of the pressure control components to mitigate the adverse pressure condition.   
     
     
         2 . The method of  claim 1 , further comprising adjusting a second of the at least two pressure control components to mitigate the adverse pressure condition. 
     
     
         3 . The method of  claim 1 , wherein the prioritizing is based on at least one of downhole drilling requirements, impact on rate of penetration, impact on bottom hole cleaning, speed of response, downhole drilling requirements, or magnitude of desired change in pressure. 
     
     
         4 . The method of  claim 1 , wherein the monitoring the bottom hole pressure further comprises at least one of measuring at least one selected from a mud tank level, a flow rate of drilling fluid entering the drillstring, a flow rate of solids laden drilling fluid exiting an annulus of the well bore, or a surface pressure of a drilling riser. 
     
     
         5 . The method of  claim 1 , wherein a fluid loss condition is detected and the adjusting comprises at least one selected from the group consisting of decreasing a pump rate of a rig pump, increasing a pump rate of the riser pump, opening a control choke, and decreasing a weight of the drilling fluid pumped downhole. 
     
     
         6 . The method of  claim 1 , wherein a fluid gain condition is detected and the adjusting comprises at least one selected from the group consisting of increasing a pump rate of a rig pump, decreasing a pump rate of the riser pump, closing a control choke, and increasing a weight of the drilling fluid pumped downhole. 
     
     
         7 . The method of  claim 1 , wherein the monitoring further comprises relaying measurements from a plurality of sensors disposed about a drilling system, including the drill string and pressure control components, to a programmable logic controller. 
     
     
         8 . The method of  claim 1 , wherein the adjusting includes automatically adjusting the at least one of the pressure control components based on the prioritized response. 
     
     
         9 . A method comprising:
 pumping a drilling fluid down a drill string at a first pump pressure, while maintaining a first casing pressure, and first riser level;   identifying a at least two pressure control components to maintain at least one of a casing pressure, pump pressure, and/or riser level;   prioritizing at least one of the pressure control components based on at least one of a length of time to implement the response, a length of time for the response to take effect, magnitude of desired change in pressure, or drilling requirements; and   adjusting one of the at least two pressure control components to maintain at least one of the casing pressure, pump pressure, or riser level.   
     
     
         10 . The method of  claim 9 , further comprising detecting an adverse fluid condition, wherein the adverse fluid condition is one selected from a fluid loss condition or the fluid gain condition. 
     
     
         11 . The method of  claim 9 , further comprising operatively connecting the at least two pressure control components to a programmable logic controller. 
     
     
         12 . The method of  claim 11 , wherein the adjusting further comprises sending instructions from the programmable logic controller to the at least one of the pressure control components based on the analysis of the response. 
     
     
         13 . The method of  9 , further comprising monitoring a bottom hole pressure after adjusting one of the at least two pressure control components. 
     
     
         14 . The method of  claim 13 , further comprising determining the adverse pressure condition persists and adjusting a second of the at least two pressure control components. 
     
     
         15 . The method of  claim 9 , wherein the detecting further comprises transmitting a signal from a sensor to a programmable logic controller measuring at least one selected from the group consisting of a mud tank level, a flow rate of drilling fluid entering the drillstring, a flow rate of solids laden drilling fluid exiting an annulus of the well bore, and a surface pressure of a drilling riser. 
     
     
         16 . The method of  claim 9 , further comprising inputting the measurements into a model of the well bore to determine a presence of the adverse pressure condition. 
     
     
         17 . The method of  claim 9 , wherein the adjusting further comprises adjusting the at least two pressure control components simultaneously. 
     
     
         18 . A system comprising:
 a drill string;   at least two bottom hole pressure control components operatively coupled to the drill string;   a programmable logic controller operatively connected to the at least two bottom hole pressure control components; and   a processor operatively connected to the programmable logic controller and configured to prioritize one of the at least two bottom hole pressure control components during a detected change in pressure.   
     
     
         19 . The system of  claim 18 , wherein the at least two bottom hole pressure control components are selected from the group consisting of a rig pump, a riser pump, a control choke, and a mud tank. 
     
     
         20 . The system of  claim 18 , further comprising a plurality of sensors operatively connected to the drill string and the at least two bottom hole pressure control components.