Patent Publication Number: US-11655690-B2

Title: Borehole cleaning monitoring and advisory system

Description:
TECHNICAL FIELD 
     This disclosure relates to wellbore drilling operations. 
     BACKGROUND 
     In wellbore drilling operations, a drilling system causes a drill bit to rotate when in contact with a formation. The rotation of the drill bit breaks and fractures the formation to form the wellbore. The portions of the formation that are broken off during drilling are referred to as “formation cuttings.” In order to remove the cuttings from the wellbore, the drilling system circulates a drilling fluid (also referred to as “drilling mud” or “mud”) to the drill bit. The drilling fluid exits through drill bit nozzles to the bottom of the wellbore. The drilling fluid carries the formation cuttings from the wellbore to the surface. The ability of the drilling fluid to carry the formation cuttings out of the wellbore is referred to as a carrying capacity of the drilling fluid. 
     SUMMARY 
     In existing practice, methods or software for evaluating hole cleaning in real-time does not exist. In particular, there are no real time values or profiles for hole cleaning indicators in existing practice. Additionally, in existing practice, determining equivalent circulating density is only possible using a specialized pressure while drilling (PWD) tool. Further, currently drilling fluid density can only be calculated commercialized devices. 
     This disclosure describes methods and systems for improving a borehole cleaning efficiency of a borehole drilling operation. In one embodiment, a hole cleaning advisory system (HCAS) calculates indicators that are used to evaluate the borehole cleaning efficiency. To do so, the HCAS receives well data that includes surface rig sensor data and mud rheological properties. The HCAS uses a borehole model and the well data to calculate the borehole cleaning efficiency indicators. The indicators are then used by the HCAS to monitor and evaluate the borehole cleaning efficiency. Monitoring the borehole cleaning efficiency allows the HCAS to help a drilling system (that is performing the drilling operation) to avoid drilling problems. In particular, the HCAS can use the borehole cleaning efficiency to generate recommendations (for example, corrective actions) for improving the drilling operation. In some examples, the HCAS can perform corrective actions based on the recommendations. For instance, the HCAS can control a drilling tool to adjust a drilling parameter that mitigates a detected problem. 
     Innovative aspects of the subject matter described in this disclosure may be embodied in methods that include the actions of: receiving real-time drilling data of a drilling operation of drilling a wellbore; using the drilling data to calculate at least one indicator of a borehole cleaning efficiency of the drilling operation; detecting, based on the least one indicator of the borehole cleaning efficiency, a drilling problem with the drilling operation; determining a corrective action to avoid or mitigate the drilling problem; and performing the corrective action to avoid or mitigate the drilling problem. 
     Other embodiments of these aspects include corresponding systems, apparatus, and computer programs, configured to perform the actions of the methods, encoded on computer storage devices. These and other embodiments may each optionally include one or more of the following features. 
     In some implementations, performing the corrective action involves: controlling the drilling system to adjust one or more drilling parameters that avoid or mitigate the drilling problem. 
     In some implementations, the drilling parameters comprise: a rate of penetration (ROP) of a drilling tool of the drilling system, a hole size of the wellbore, and a flow rate (GPM) of the drilling fluid. 
     In some implementations, controlling, based on the effective mud weight, a component of the drilling system to adjust at least one of the drilling parameters involves: determining, based on the real-time drilling data, a rate of penetration for a drilling tool of the drilling system; and controlling the drilling tool such that the rate of penetration of the drilling tool is less than or equal to the determined rate of penetration. 
     In some implementations, determining the rate of penetration for the drilling tool is further based on a pore pressure limit and a fracture pressure limit. 
     In some implementations, performing the corrective action involves displaying, via a graphical user interface (GUI), drilling instructions to perform one or more actions to avoid or mitigate the drilling problem. 
     In some implementations, the least one indicator of the borehole cleaning efficiency comprises at least one of: (1) a modified carrying capacity index (CCI), (2) a modified cuttings concentration in annulus (CCA), (3) a transport ratio (TR) efficiency (TRE), (4) an effective drilling fluid density (MWeff), (5) an equivalent circulating density (ECD), or (6) transport index (TI). 
     Particular implementations of the subject matter described in this specification can be implemented so as to realize one or more of the following advantages. As an example, implementation of the subject matter improve drilling operations by minimizing stuck drilling pipe incidents due to bad hole cleaning, improving the drilling rate efficiency, minimizing non-productive time due to bad hole cleaning, and minimizing lost resources due to circulation incidents. As another example, implementation of the subject matter improve on existing systems by evaluating cuttings accumulation in annulus, evaluating drilling fluid in real-time, and determining equivalent circulating density without specialized tools. As yet another example, implementation of the subject matter can be applied in any drilling scenarios with any types of drilling fluid system and mud solid control equipment system. 
     The details of one or more implementations of the subject matter described in this disclosure are set forth in the accompanying drawings and the description. Other features, aspects, and advantages of the subject matter will become apparent from the description, the drawings, and the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    illustrates a hole cleaning advisory system (HCAS), according to some implementations of the present disclosure. 
         FIG.  2    illustrates a table of example values of borehole cleaning indicators, according to some implementations of the present disclosure. 
         FIG.  3    illustrates a table of example recommendations generated based on the values of the borehole cleaning indicators, according to some implementations of the present disclosure. 
         FIG.  4    illustrates a flowchart of an example method, according to some implementations of the present disclosure. 
         FIG.  5    illustrates an example computing environment for implementing the techniques described herein, according to some implementations of the present disclosure. 
         FIG.  6    is a partial schematic perspective view of an example rig system for drilling and producing a well, according to some implementations of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     This disclosure describes methods and systems for improving a borehole cleaning efficiency of a borehole drilling operation. In one embodiment, a hole cleaning advisory system (HCAS) calculates indicators that are used to evaluate the borehole cleaning efficiency. To do so, the HCAS receives well data that includes surface rig sensor data and mud rheological properties. The HCAS uses a borehole model and the well data to calculate the borehole cleaning efficiency indicators. The indicators are then used by the HCAS to monitor and evaluate the borehole cleaning efficiency. Monitoring the borehole cleaning efficiency allows the HCAS to help a drilling system (that is performing the drilling operation) to avoid drilling problems. In particular, the HCAS can use the borehole cleaning efficiency to generate recommendations (for example, corrective actions) for improving the drilling operation. In some examples, the HCAS can perform corrective actions based on the recommendations. For instance, the HCAS can control a drilling tool to adjust a drilling parameter that mitigates a detected problem. 
     For the purposes of this disclosure, the terms “real-time,” “real time,” “realtime,” or similar terms (as understood by one of ordinary skill in the art) mean that an action and a response are temporally proximate such that an individual perceives the action and the response occurring substantially simultaneously. For example, the time difference for a response to display (or for an initiation of a display) of data following the action of an individual to access the data may be less than 1 millisecond (ms), less than 1 second, or less than 5 seconds. While the requested data need not be displayed (or initiated for display) instantaneously, it is displayed (or initiated for display) without any intentional delay, taking into account processing limitations of a described computing system and time required to, for example, gather, accurately measure, analyze, process, store, and/or transmit the data. 
       FIG.  1    illustrates a hole cleaning advisory system (HCAS)  100 , according to some implementations. In one embodiment, the HCAS  100  is implemented using a computer system, such as the computer system  500  of  FIG.  5   . As described in  FIG.  5   , the computer system  500  can communicate with one or more other computer systems over one or more networks. Note that the HCAS  100  is shown for illustration purposes only, as the HCAS  100  can include additional components or have one or more components removed without departing from the scope of the disclosure. Further, note that the various components of the HCAS  100  can be arranged or connected in any manner. 
     In some embodiments, the HCAS  100  is a computer-based system that is configured to monitor a drilling operation, provide drilling recommendations to operators, and control a drilling system performing the drilling operation. More specifically, the HCAS  100  is configured to monitor and evaluate borehole cleaning efficiency during the drilling operation. As described in more detail below, monitoring and evaluating the borehole cleaning efficiency enables that HCAS  100  to improve the drilling operation, for example, by proactively avoiding drilling problems or reactively mitigating a detected drilling problem. In one example, the HCAS  100  is configured to generate recommendations that improve the drilling operation. The HCAS  100  can provide drilling teams (or operators) with the recommendations, perhaps, by displaying the recommendation on a user device display or by providing a user notification (for example, an audible, visual, or tactile alert). Additionally or alternatively, the HCAS  100  can take actions based on the borehole cleaning efficiency or the generated recommendations, such as corrective actions that mitigate detected drilling problems, actions that proactively improve the drilling operation, or both. 
     In some embodiments, the HCAS  100  receives drilling data  102 . As shown in  FIG.  1   , the drilling data  102  includes rig sensor data  112  and drilling fluid (mud) properties  114 . The rig sensor data  112  includes data that has been measured by rig sensors, such as surface rig sensors and other devices that are configured for real-time surface and down-wellbore measurements. Examples of the rig sensor data  112  include measurement-while-drilling (MWD) data, logging-while-drilling (LWD) data, drilling rate, rate of penetration (ROP), torque (that is, the movement required to rotate the drilling pipe), spindle speed (that is, the rotation frequency of the spindle of the drilling system, measured in RPM), weight on bit (that is, the amount of downward force exerted on the drilling bit provided by the thick-walled tubular pieces in the drilling assembly), and standard pipe pressure (that is the summation of pressure loss in annulus, pressure loss in drill string, pressure loss in bottom hole assembly (BHA) and pressure loss across the bit), mudflow volume, mud pressure, mud resistivity, gas readings, among other examples. Examples of the mud or drilling fluid properties  114  includes drilling fluid density, viscosity, yield point, gel strength, filtration, and rheology. Other examples of the drilling data  102  include a hole size of the borehole and dimensions of the drill pipe. 
     In some embodiments, the HCAS  100  uses a model  104  that represents the drilling operation in order to interpret the drilling data  102 . The model  104  can be a real-time model of the drilling operation. The HCAS  100  generates the model  104  based on a plurality of predetermined mathematical equations that define parameters for evaluating a borehole cleaning efficiency of the drilling operation. In an example, the model  104  is configured to use the drilling data  102  to calculate one or more of the following hole cleaning indicators  116 : (1) a modified carrying capacity index (CCI), (2) a modified cuttings concentration in annulus (CCA), (3) a transport ratio (TR) efficiency (TRE), (4) an effective drilling fluid density (MWeff), (5) an equivalent circulating density (ECD), and (6) transport index (TI). The hole cleaning indicators  116  enable the HCAS  100  to evaluate the borehole cleaning efficiency. Based on the borehole cleaning efficiency, the HCAS  100  can detect potential drilling problems, determine corrective actions to mitigate potential or actual drilling problems, or generate recommendations for improving the drilling operation. 
     In some embodiments, the model  104  accounts for one or more of the following drilling operation factors: (1) borehole depth and inclination, (2) real-time mud weight, (3) real-time ECD, (4) CCI, (5) CCA, (6) TR, (7) mud lifting capacity, (8) bottom hole assembly (BHA) design, (9) effective viscosity of the drilling fluid, (10) apparent viscosity of the drilling fluid, (11) rheology properties of the drilling fluid, (12) drilling fluid type (for example, oil or water based), (13) hole section type (for example, vertical, deviated, or horizontal), (14) specific gravity of the drilling fluid, (15) low shear yield point (LSYP), (16) temperature effect, (17) connection time, (18) annular borehole area (for example, cased or open hole), (19) cuttings size and density, (20) TI, (21) angle factor, (22) velocity TR, (23) drill bit friction, and (24) circulation and rotation factor. 
     In some embodiments, the HCAS  100  generates the model  104  in order to provide information indicative of the hole cleaning efficiency optimization. In an example, the HCAS  100  generates the model  104  by applying data mining techniques to the drilling data  102 . In some embodiments, machine learning algorithms are applied to the drilling data  102  in order to enhance well drilling and rig performance. The model  104  enables continuous monitoring and evaluation of hole cleaning efficiency while drilling to avoid hole problems and optimize well drilling performance. Additionally, the model  104  enables immediate intervention when the borehole is not being cleaned properly. Further, the model  104  provide information indicative of hole cleaning efficiency and ROP performance optimization. 
     In some embodiments, the model  104  calculates the hole cleaning indicators  116  using Equations [1]-[44] defined below. More specifically, Equations [1]-[21] are used to calculate fundamental drilling variables, Equations [22]-[25] are used to calculate TRE, Equation [26] is used to calculate effective ECD (ECD eff ), Equations [27]-[29] are used to calculate MW effc , Equations [30]-[33] are used to calculate CCA, and Equations [34]-[44] are used to calculate CCI. MWeffc is the mud weight with the influence of drilling cuttings, rheological properties, and annular pressure effect. 
     As stated, Equations [1]-[21] are used to calculate fundamental variables, which in turn, can be used to calculate the hole cleaning indicators  116 . 
                   dc   =     0.2       (       1   +     RO   ⁢   P         1   +     RP   ⁢   M         )     .               [   1   ]               
In Equation [1], dc is a cutting diameter, ROP is rate of penetration of the drilling bit, and RPM is the rate of rotation of the drill bit in rotations per minute. Equation [2] is used to calculate low shear yield point (LSYP) based on the rate of rotation of the drill bit:
 
LSYP=2(3 RPM)−6 RPM.   [2]
 
Equation [3] is used to calculate a slip velocity of the cuttings, V sa :
 
                     V     s   ⁢   a       =           V     s   ⁢   5       +     V   sc       2     .             [   3   ]               
In Equation [3], V sc  is a cuttings velocity (defined in Equation [4]), and V s5  is a velocity factor (defined in Equation [6]). Equation [4] is used to calculate the cuttings velocity:
 
                     V     s   ⁢   c       =         2   ⁢     4   .   5     ⁢     (     1   +   GPM     )           OH   2     -     DP   2         -       V   cr     .               [   4   ]               
In Equation [4], V cr  is a cuttings rise velocity (defined in Equation [5]), OH is an open hole size of the borehole, DP is a diameter of the borehole, and GPM is a flow rate of the drilling fluid in gallons per minute (GPM). Equation [5] is used to calculate the cuttings rise velocity:
 
                     V   cr     =         6   ⁢   0         (     1   -       (       O   ⁢     D   pipe         Hole   ⁢         size       )     2       )     *     (     0.64   +     18.16     1   +     R   ⁢   O   ⁢   P           )         .             [   5   ]               
In Equation [5], OD pipe  is a diameter of the drill pipe, and “Hole size” is a diameter of the borehole (in feet).
 
     Equation [6] is used to calculate a velocity factor (V s5 ): 
                     V     s   ⁢   5       =       (         V     s   ⁢   1       +     V     s   ⁢   2       +     V     s   ⁢   3       +     V     s   ⁢   4         4     )     ⁢     (         2   .   1     ⁢   1   ⁢   7     -         0   .   1     ⁢   6   ⁢   4   ⁢   8   ⁢   M   ⁢     W   eff       7.481     +       0   .   0     ⁢   0   ⁢   3   ⁢   6   ⁢   8   ⁢   1   ⁢         (       M   ⁢     W   eff       7.481     )     2     .                     [   6   ]               
In Equation [6], MW eff  is an effective drilling fluid density in pounds per gallon (lb/gal) and is defined in Equation [20], V s1  is a cuttings velocity calculated based on effective viscosity (defined in Equation [7]), V s2  is a cuttings velocity calculated based on apparent viscosity (defined in Equation [8]), V s3  defined in Equation [9], and V s4  is defined in Equation [10]. Equation [7] is used to calculate the cuttings velocity calculated based on effective viscosity:
 
                     V     s   ⁢   1       =       0   .   4     ⁢   5   ⁢     (       P   ⁢   V       (     MWeff   *   dc     )       )     ⁢     (         (           3   ⁢   6   ⁢   8   ⁢   0   ⁢   0         (       P   ⁢   V       MWeff   *   dc       )     2       ⁢   d   ⁢     c   ⁡   (         W   ⁢   c     MWeff     -   1     )       +     1     -   1         )       0   .   5       .                 [   7   ]               
In Equation [7], PV is a plastic viscosity of the drilling fluid in centiPoise (CP) and We is a cuttings density defined in Equation [11]. Equation [8] is used to calculate the cuttings velocity calculated based on apparent viscosity:
 
                     V     s   ⁢   2       =         0   .   4     ⁢   5   ⁢     (     Meff     (     MWeff   *   d   ⁢   c     )       )     ⁢       (         (     3   ⁢   6   ⁢   8   ⁢   0   ⁢   0     )     ⁢     (   MWeff   )     ⁢     (     d   ⁢     c   3       )     ⁢     (       W   ⁢   c     -   MWeff     )         Meff   2       )       0   .   5         .             [   8   ]               
In Equation [8], Meff an effective viscosity of the drilling fluid defined in Equation [19].
 
                     V     s   ⁢   3       =       (       1   ⁢   7   ⁢   5   ⁢     (     d   ⁢   c     )     ⁢       (     Wc   -   MWeff     )         0   .   6     ⁢   6   ⁢   7             MWeff   0.333     ⁢     Mapp       0   .   3     ⁢   3   ⁢   3           )     .             [   9   ]               
In Equation [9], Mapp is an apparent viscosity of the drilling fluid (defined in Equation [14]).
 
                     V     s   ⁢   4       =       (       1   ⁢   7   ⁢   5   ⁢     (     d   ⁢   c     )     ⁢       (       W   ⁢   c     -   MWeff     )         0   .   6     ⁢   6   ⁢   7             MWeff       0   .   3     ⁢   3   ⁢   3       ⁢     Meff       0   .   3     ⁢   3   ⁢   3           )     .             [   10   ]                           Wc   =       (   MWeff   )     +       (     1   -     CCA   ⁢   3       )     *       (   MWeff   )     .                 [   11   ]               
In Equation [11], CCA3 is defined in Equation [33].
 
                   Vannc   =       (       Vann   +   VannInc     2     )     ⁢       (     1   -     CCAm   ⋆     Vsa     (       Vann   +   VannInc     2     )           )     .               [   12   ]               
In Equation [12], Vann is an annular velocity of the drilling fluid (in feet/minute) and is defined in Equation [21], VannInc is defined in Equation [13], and CCAm is defined in Equation [30].
 
VannInc=Vsa*cos(HA)+Vtr*sin(HA).
 
In Equation [13], HA is hole angle of inclination.
 
     Equation [14] defines the apparent viscosity of the drilling fluid: 
                   Mapp   =         2.4   Vann         O   ⁢   H     -     O   ⁢   D         ⁢       (         2   ⁢   n     +   1       3   ⁢   n       )     n     ⁢       (       2   ⁢   0   ⁢   0   ⁢     K   ⁡   (       O   ⁢   H     -     O   ⁢   D       )       Vann     )     .               [   14   ]               
In Equation [14], K is a consistency factor (defined in Equation [39]) and n is a flow behavior index of the drilling fluid (defined in Equation [38]).
 
                     V     ann   ⁢   _   ⁢   dc       =         2   ⁢     4   .   5     ⁢     (     1   +   GPM     )           Hole   ⁢           size   2       -     OD   c   2         .             [   15   ]               
In Equation [15], OD c  is a casing diameter.
 
                   Vc   =       (       (       1   +   ROP       6   ⁢   0       )     /     (         3.14   4       (     Hole   ⁢           size   2       )         1   ⁢   4   ⁢   4       )       )     .             [   16   ]                           VannDp   =         2   ⁢     4   .   5     ⁢     (     1   +   GPM     )           Hole   ⁢           size   2       -     OD   pipe   2         .             [   17   ]                             Y   ⁢   Pc     =       (       0.5     (       Y   ⁢   P     +     LSY   ⁢   P       )         0.75        Y   ⁢   P       )     ⁢   Y   ⁢     P   .               [   18   ]               
In Equation [18], YP is a yield point of the drilling fluid in lb/100 ft 2 .
 
                   Meff   =     PV   +     300   *   Y   ⁢       Pc   ⁡   (       d   ⁢   c     Vann     )     .                 [   19   ]                           MWeff   =       M   ⁢       W   *   CCA     +     M   ⁢     W   .                 [   20   ]               
In Equation [20], MW is the static drilling fluid density (that is, the drilling fluid density without any cuttings). MWeff is the mud weight that accounts for the influence of drilling cuttings.
 
     
       
         
           
             
               
                 
                   Vann 
                   = 
                   
                     
                       
                         2 
                         ⁢ 
                         
                           4 
                           . 
                           5 
                         
                         ⁢ 
                         
                           ( 
                           
                             1 
                             + 
                             GPM 
                           
                           ) 
                         
                       
                       
                         
                           Hole 
                           ⁢ 
                               
                           
                             size 
                             2 
                           
                         
                         - 
                         
                           OD 
                           pipe 
                           2 
                         
                       
                     
                     . 
                   
                 
               
               
                 
                   [ 
                   21 
                   ] 
                 
               
             
           
         
       
     
     As stated, Equations [22]-[25] are used to calculate TRE. 
                   TR   =       (     1   -         V     s   ⁢   5       *   Wc         V     a   ⁢   n   ⁢   n   ⁢   c       *   ECDeff         )     .             [   22   ]               
In Equation [22], ECDeff is defined in Equation [26].
 
                   Vtr   =     60   ⁢         (       (       Wc   -   MWeff     MWeff     )     ⁢       (   32.2   )     3     ⁢       (       OH   -   OD     12     )     3       )       1   6       .               [   23   ]                             α   ⁢   m   ⁢   c     =       (       α   ⁢   m     +   CCA     )     .             [   24   ]               
In Equation [24], αm is an open hole and drillstring components annular clearance, and αmc is an open hole and drillstring components annular clearance with cuttings effect.
 
                     1     α   ⁢   m       =       (         OH   2     -     ODc   2         OH   2       )     +     (         Liner_Dl   2     -     OD   2         OH   2       )     +     (         ID   csg   2     -     OD   2         OH   2       )     +       (         OH   2     -     OD   2         OH   2       )     .               [   25   ]               
In Equation [25], ID csg   2  is an inner diameter of the last casing, and Liner Dl     2    is an inner diameter of the last liner that was run.
 
                       ECDeffc   =     MWeffc   +       (       (       (     0.1     OH   -   ODDP       )     ⁢     (       Y   ⁢   Pc     +         PV   ⁡   (     α   ⁢   m   ⁢   c     )     ⁢     (   VannC   )         3   ⁢   0   ⁢   0   ⁢     (     OH   -   OD     )           )       )     ⁢     7   .   4     ⁢   81     )     ⁢     (       S   ⁢   P   ⁢   Px       S   ⁢   P   ⁢   P   ⁢   1       )     ⁢     (     Depthx     Depth   ⁢   1       )           )     .           [   26   ]               
In Equation [26], SPPX is a current (real-time) stand pipe pressure (SPP), SPP1 is a first SPP when ROP is greater than 1, Depth1 is a start measured hole depth, and DepthX is a current measured hole depth.
 
     As stated, Equations [27]-[29] are used to calculate MW effc . 
     
       
         
           
             
               
                 
                   MWeffc 
                   = 
                   
                     
                       ( 
                       
                         
                           M 
                           ⁢ 
                           W 
                           * 
                           CCAm 
                           * 
                           
                             ( 
                             
                               
                                 α 
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                           ⁢ 
                           P 
                           ⁢ 
                           x 
                         
                       
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                     - 
                     
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                         depthx 
                         
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                           ⁢ 
                           1 
                         
                       
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                     - 
                     
                       BF 
                       . 
                     
                   
                 
               
               
                 
                   [ 
                   27 
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                     ⁢ 
                         
                     
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                           &amp; 
                         
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                         Rotation 
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                         factor 
                       
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                   = 
                   
                     
                       
                         ( 
                         
                           
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                               1 
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                   [ 
                   28 
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                       BF 
                       ⁢ 
                           
                       
                         ( 
                         
                           bit 
                           ⁢ 
                               
                           friction 
                         
                         ) 
                       
                     
                     = 
                     
                       
                         
                           1 
                           ⁢ 
                           2 
                           ⁢ 
                           
                             ( 
                             
                               1 
                               + 
                               torque 
                             
                             ) 
                           
                         
                         
                           
                             ( 
                             
                               1 
                               + 
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                             ) 
                           
                           ⁢ 
                               
                           Hole 
                           ⁢ 
                               
                           size 
                         
                       
                       . 
                     
                   
                 
               
               
                 
                   [ 
                   29 
                   ] 
                 
               
             
           
         
       
     
     As stated, Equations [30]-[33] are used to calculate CCA. 
     
       
         
           
             
               
                 
                                    
                   
                     CCAm 
                     = 
                     
                       
                         ( 
                         
                           
                             C 
                             ⁢ 
                             C 
                             ⁢ 
                             A 
                             ⁢ 
                             1 
                           
                           + 
                           
                             C 
                             ⁢ 
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                             ⁢ 
                             A 
                             ⁢ 
                             2 
                           
                           + 
                           
                             CCA 
                             ⁢ 
                             3 
                           
                         
                         ) 
                       
                       / 
                       3. 
                     
                   
                 
               
               
                 
                   [ 
                   30 
                   ] 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     CCA 
                     ⁢ 
                     1 
                   
                   = 
                   
                     
                       
                         - 
                         
                           1 
                           2 
                         
                       
                       ⁢ 
                       
                         ( 
                         
                           
                             Vann 
                             Vsa 
                           
                           - 
                           1 
                         
                         ) 
                       
                     
                     + 
                     
                       
                         
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                               ⁢ 
                               
                                 
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                             + 
                             
                               
                                 Vann 
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                               × 
                               
                                 Vann 
                                 Vsa 
                               
                               ⁢ 
                               
                                 Vc 
                                 
                                   
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                                   7.48 
                                 
                               
                             
                           
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                       . 
                     
                   
                 
               
               
                 
                   [ 
                   31 
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                                 + 
                                 
                                   
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                   [ 
                   32 
                   ] 
                 
               
             
           
         
       
       
         
           
             
               
                 
                                    
                   
                     
                       CCA 
                       ⁢ 
                       3 
                     
                     = 
                     
                       
                         
                           
                             ( 
                             
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                               + 
                               
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                           ⁢ 
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                             ( 
                             
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                               + 
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                             ) 
                           
                           ⁢ 
                           
                             ( 
                             TR 
                             ) 
                           
                         
                       
                       . 
                     
                   
                 
               
               
                 
                   [ 
                   33 
                   ] 
                 
               
             
           
         
       
     
     As stated, Equations [ 34 ] — [ 44 ] are used to calculate CCI. 
                     CCI   ⁢   1     =       (       MWeffc   *   K   *     V   annc         2   ⁢   9   ⁢   9   ⁢   2   ⁢   4   ⁢   0   ⁢   0       )     .             [   34   ]                             CCI   ⁢   2     =       (     KTI     598   ⁢        Aa   ⁢        RF       )     .             [   35   ]                             CCI   ⁢   3     =           (   MWeffc   )     ⁢     (   K   )     ⁢   Af       3   ⁢   7   ⁢   3   ⁢   1   ⁢   5   ⁢   A   ⁢   a       .             [   36   ]                           CCIm   =       (       CCI   ⁢   1     +     CCI   ⁢   2     +     CCI   ⁢   3       )     /   3.             [   37   ]                           n   =     3.   3   ⁢   2   *       log   ⁡   (         2   ⁢   PV     +     Y   ⁢   Pc         PV   +     Y   ⁢   Pc         )     .               [   38   ]                           K   =     51   ⁢     1     1   -   n       ⁢       (     PV   -     Y   ⁢   Pc       )     .               [   39   ]                           SG   =       MWeffc   62.4     .             [   40   ]                           RF   =       0   .   5     ⁢     (       pv     y   ⁢   pc       +       y   ⁢   pc     pv       )     ⁢       (     1   -         T   ⁢   2       T   ⁢   1       *   CCA       )     .               [   41   ]               
In Equation [41], T2 &amp; T1 Temperatures of hole. RF is a rheology factor.
 
                     A   ⁢   a     =       3.14     4   *   1   ⁢   4   ⁢   4           (       OH   2     -     OD   2       )     .               [   42   ]               
Equation [42] defines an annulus area, Aa.
 
AF=(0.0001*(HA) 2 −0.0255*HA+2.0784)(1−CCA).   [43]
 
TI=AF*RF*SG.   [44]
 
     In some embodiments, the HCAS  100  monitors the one or more indicators  116  by assessing the values of the one or more indicators  116 . In an example, each indicator  116  is associated with an optimized range of values, an acceptable range of values, and an unacceptable range of values. In this example, the HCAS  100  can determine that the status of a particular indicator based on whether the current value of the indicator is within the optimized range, the acceptable range, or the unacceptable range of values. 
       FIG.  2    illustrates a table  200  of example values for a borehole cleaning indicators, according to some implementations. In particular, the table  200  includes example ranges for the transport ratio, cuttings concentration in the annulus, carrying capacity index, and transport index. As shown in table  200 , the transport ratio is optimized if its current value is greater than 0.65, is acceptable if the current value is between 0.5 and 0.65, and unacceptable if the current value is less than or equal to 0.5. The cuttings concentration in the annulus is optimized if its current value is less than or equal to 0.05 and greater than 0.03, acceptable if its current value is less than or equal to 0.03 and greater than or equal to 0, and unacceptable if its current value is greater than 0.05. The carrying capacity index is optimized if its current value is greater than 3, acceptable if its current value is less than or equal to 3 and greater 3, and unacceptable if its current value is less than or equal to 1. The transport index is optimized if its current value is greater than 2.5, acceptable if its current value is less than 2.5 and greater than or equal to 1.5, and unacceptable if its current value is less than 1.5. 
     In some embodiments, the HCAS  100  uses the model  104  to continuously or periodically monitor and evaluate borehole cleaning efficiency to avoid hole problems and improve well drilling performance. For example, the HCAS  100  is configured to intervene by performing a corrective action when a wellbore is not being cleaned properly. Further, the HCAS  100  can use the borehole cleaning efficiency to determine actions that improve the well drilling performance, such as determining a rate of penetration (ROP) that improves the drilling operation (for example, by improving the efficiency of the drilling operation). Furthermore, the HCAS  100  can send instructions to other drilling tools or systems to perform actions that avoid hole problems or improve well drilling performance. In some examples, the HCAS  100  generates recommendations based on a predetermined set of rules or guidelines. Example guidelines include: (i) increase GPM only if less than recommended, (ii) increase ROP only when possible, and (iii) reduce ROP only where the operation is drilling. 
       FIG.  3    illustrates a table  300  of example recommendations generated based on the values of the borehole cleaning indicators, according to some implementations. In this example, the table  300  includes recommendations based on the values of CCA, CCI, and TR. In table  300 , the value of a particular indicator being within an optimized range is represented by “Green,” within an acceptable range is represented by “Yellow,” and within an unacceptable range is represented by “Red.” As shown in table  300 , example recommendations include controlling the rate of penetration (ROP), controlling the rheological properties of the drilling fluid, and controlling the rate of flow of the drilling fluid (GPM). 
     In some embodiments, the HCAS  100  can display the recommendations on a display. As an example, the HCAS  100  can display, for example, to drilling teams, down hole readings from surface reading usage. The HCAS  100  can also provide drilling teams with continuous monitoring, evaluation, optimization, and recommendations regarding hole cleaning performance and efficiency. As such, the HCAS  100  helps mitigate hole problems and improves drilling rate, which results in safer and more economical wells. 
     In some embodiments, the HCAS  100  can determine to make one or more adjustments to the drilling operation (for example, by controlling a component or system of the drilling system of  FIG.  6   ), perhaps to meet changing downhole conditions. As an example, the HCAS  100  can send instructions to a mud system to circulate cuttings to the surface and ensure smooth drilling rate based on the desired mud efficiency. The adjustments may be to surface properties, mechanical parameters (for example, ROP, flow rate, pipe-rotation speed, and tripping speed), or both. In response to making the determination to make one or more adjustments, the HCAS  100  adjusts the operating parameters of one or more components of the HCAS  100  to adjust the surface properties, the mechanical parameters, or both. 
     In one example, the HCAS  100  determines a maximum rate of penetration for a drill bit of drilling system (for example, the drilling system of  FIG.  6   ). More specifically, the effective drilling fluid density, a pore pressure limit of the formation, and a fracture pressure limit of the formation are used to calculate the stability of the formation. Then, based on the calculated stability, the maximum rate of penetration is calculated. Additionally, the HCAS  100  can control the rate of penetration, perhaps to be less than the calculated maximum rate. Controlling the rate of penetration allows the HCAS  100  to: (i) avoid fracturing the formation while drilling, (ii) ensure smooth drilling with generated drilling cuttings, and (iii) avoid or mitigate stuck pipe incidents. In an example, the rate of penetration may be calculated using the effective drilling fluid density using Equation [45]: 
     
       
         
           
             
               
                 
                   
                     R 
                     ⁢ 
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                     P 
                   
                   = 
                   
                     
                       
                         8 
                         ⁢ 
                         1 
                         ⁢ 
                         0 
                         * 
                         
                           ( 
                           
                             
                               M 
                               ⁢ 
                               
                                 W 
                                 eff 
                               
                             
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                               M 
                               ⁢ 
                               W 
                             
                           
                           ) 
                         
                         * 
                         G 
                         ⁢ 
                         P 
                         ⁢ 
                         M 
                       
                       
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                     . 
                   
                 
               
               
                 
                   [ 
                   45 
                   ] 
                 
               
             
           
         
       
     
       FIG.  4    is a flowchart of an example method  400 , according to some implementations. The method  400  is for improving a borehole cleaning efficiency of a borehole drilling operation by calculating and monitoring real-time indicators of borehole cleaning efficiency. For clarity of presentation, the description that follows generally describes method  400  in the context of the other figures in this description. However, it will be understood that method  400  can be performed, for example, by any suitable system, environment, software, hardware, or a combination of systems, environments, software, and hardware, as appropriate. In some implementations, various steps of method  300  can be run in parallel, in combination, in loops, or in any order. 
     At step  402 , method  400  involves receiving real-time drilling data of a drilling operation of drilling a wellbore. 
     At step  404 , method  400  involves using the drilling data to calculate at least one indicator of a borehole cleaning efficiency of the drilling operation. 
     At step  406 , method  400  involves detecting, based on the least one indicator of the borehole cleaning efficiency, a drilling problem with the drilling operation. 
     At step  408 , method  400  involves determining a corrective action to avoid or mitigate the drilling problem; and 
     At step  410 , method  400  involves performing the corrective action to avoid or mitigate the drilling problem. 
       FIG.  5    is a block diagram of an example computer system  500  that can be used to provide computational functionalities associated with described algorithms, methods, functions, processes, flows, and procedures described in the present disclosure, according to some implementations of the present disclosure. In some implementations, the HCAS  100  can be the computer system  500 , include the computer system  500 , or include part of the computer system  500 . In some implementations, the HCAS  100  can communicate with the computer system  500 . 
     The illustrated computer  502  is intended to encompass any computing device such as a server, a desktop computer, embedded computer, a laptop/notebook computer, a wireless data port, a smart phone, a personal data assistant (PDA), a tablet computing device, or one or more processors within these devices, including physical instances, virtual instances, or both. The computer  502  can include input devices such as keypads, keyboards, and touch screens that can accept user information. Also, the computer  502  can include output devices that can convey information associated with the operation of the computer  502 . The information can include digital data, visual data, audio information, or a combination of information. The information can be presented in a graphical user interface (UI) (or GUI). In some implementations, the inputs and outputs include display ports (such as DVI-I+2x display ports), USB 3.0, GbE ports, isolated DI/O, SATA-III (6.0 Gb/s) ports, mPCIe slots, a combination of these, or other ports. In instances of an edge gateway, the computer  502  can include a Smart Embedded Management Agent (SEMA), such as a built-in ADLINK SEMA 2.2, and a video sync technology, such as Quick Sync Video technology supported by ADLINK MSDK+. In some examples, the computer  502  can include the MXE-5400 Series processor-based fanless embedded computer by ADLINK, though the computer  502  can take other forms or include other components. 
     The computer  502  can serve in a role as a client, a network component, a server, a database, a persistency, or components of a computer system for performing the subject matter described in the present disclosure. The illustrated computer  502  is communicably coupled with a network  530 . In some implementations, one or more components of the computer  502  can be configured to operate within different environments, including cloud-computing-based environments, local environments, global environments, and combinations of environments. 
     At a high level, the computer  502  is an electronic computing device operable to receive, transmit, process, store, and manage data and information associated with the described subject matter. According to some implementations, the computer  502  can also include, or be communicably coupled with, an application server, an email server, a web server, a caching server, a streaming data server, or a combination of servers. 
     The computer  502  can receive requests over network  530  from a client application (for example, executing on another computer  502 ). The computer  502  can respond to the received requests by processing the received requests using software applications. Requests can also be sent to the computer  502  from internal users (for example, from a command console), external (or third) parties, automated applications, entities, individuals, systems, and computers. 
     Each of the components of the computer  502  can communicate using a system bus. In some implementations, any or all of the components of the computer  502 , including hardware or software components, can interface with each other or the interface  504  (or a combination of both), over the system bus. Interfaces can use an application programming interface (API), a service layer, or a combination of the API and service layer. The API can include specifications for routines, data structures, and object classes. The API can be either computer-language independent or dependent. The API can refer to a complete interface, a single function, or a set of APIs. 
     The service layer can provide software services to the computer  502  and other components (whether illustrated or not) that are communicably coupled to the computer  502 . The functionality of the computer  502  can be accessible for all service consumers using this service layer. Software services, such as those provided by the service layer, can provide reusable, defined functionalities through a defined interface. For example, the interface can be software written in JAVA, C++, or a language providing data in extensible markup language (XML) format. While illustrated as an integrated component of the computer  502 , in alternative implementations, the API or the service layer can be stand-alone components in relation to other components of the computer  502  and other components communicably coupled to the computer  502 . Moreover, any or all parts of the API or the service layer can be implemented as child or sub-modules of another software module, enterprise application, or hardware module without departing from the scope of the present disclosure. 
     The computer  502  can include an interface  504 . Although illustrated as a single interface  504  in  FIG.  5   , two or more interfaces  504  can be used according to particular needs, desires, or particular implementations of the computer  502  and the described functionality. The interface  504  can be used by the computer  502  for communicating with other systems that are connected to the network  530  (whether illustrated or not) in a distributed environment. Generally, the interface  504  can include, or be implemented using, logic encoded in software or hardware (or a combination of software and hardware) operable to communicate with the network  530 . More specifically, the interface  504  can include software supporting one or more communication protocols associated with communications. As such, the network  530  or the interface&#39;s hardware can be operable to communicate physical signals within and outside of the illustrated computer  502 . 
     The computer  502  includes a processor  505 . Although illustrated as a single processor  505  in  FIG.  5   , two or more processors  505  can be used according to particular needs, desires, or particular implementations of the computer  502  and the described functionality. Generally, the processor  505  can execute instructions and can manipulate data to perform the operations of the computer  502 , including operations using algorithms, methods, functions, processes, flows, and procedures as described in the present disclosure. 
     The computer  502  can also include a database  506  that can hold data for the computer  502  and other components connected to the network  530  (whether illustrated or not). For example, database  506  can be an in-memory, conventional, or a database storing data consistent with the present disclosure. In some implementations, database  506  can be a combination of two or more different database types (for example, hybrid in-memory and conventional databases) according to particular needs, desires, or particular implementations of the computer  502  and the described functionality. Although illustrated as a single database  506  in  FIG.  5   , two or more databases (of the same, different, or combination of types) can be used according to particular needs, desires, or particular implementations of the computer  502  and the described functionality. While database  506  is illustrated as an internal component of the computer  502 , in alternative implementations, database  506  can be external to the computer  502 . 
     The computer  502  also includes a memory  507  that can hold data for the computer  502  or a combination of components connected to the network  530  (whether illustrated or not). Memory  507  can store any data consistent with the present disclosure. In some implementations, memory  507  can be a combination of two or more different types of memory (for example, a combination of semiconductor and magnetic storage) according to particular needs, desires, or particular implementations of the computer  502  and the described functionality. Although illustrated as a single memory  507  in  FIG.  5   , two or more memories  507  (of the same, different, or combination of types) can be used according to particular needs, desires, or particular implementations of the computer  502  and the described functionality. While memory  507  is illustrated as an internal component of the computer  502 , in alternative implementations, memory  507  can be external to the computer  502 . 
     An application can be an algorithmic software engine providing functionality according to particular needs, desires, or particular implementations of the computer  502  and the described functionality. For example, an application can serve as one or more components, modules, or applications. Multiple applications can be implemented on the computer  502 . Each application can be internal or external to the computer  502 . 
     The computer  502  can also include a power supply  514 . The power supply  514  can include a rechargeable or non-rechargeable battery that can be configured to be either user- or non-user-replaceable. In some implementations, the power supply  514  can include power-conversion and management circuits, including recharging, standby, and power management functionalities. In some implementations, the power-supply  514  can include a power plug to allow the computer  502  to be plugged into a wall socket or a power source to, for example, power the computer  502  or recharge a rechargeable battery. 
     There can be any number of computers  502  associated with, or external to, a computer system including computer  502 , with each computer  502  communicating over network  530 . Further, the terms “client,” “user,” and other appropriate terminology can be used interchangeably, as appropriate, without departing from the scope of the present disclosure. Moreover, the present disclosure contemplates that many users can use one computer  502  and one user can use multiple computers  502 . 
     Implementations of the subject matter and the functional operations described in this specification can be implemented in digital electronic circuitry, in tangibly embodied computer software or firmware, in computer hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them. Software implementations of the described subject matter can be implemented as one or more computer programs. Each computer program can include one or more modules of computer program instructions encoded on a tangible, non-transitory, computer-readable computer-storage medium for execution by, or to control the operation of, data processing apparatus. Alternatively, or additionally, the program instructions can be encoded in/on an artificially generated propagated signal. The example, the signal can be a machine-generated electrical, optical, or electromagnetic signal that is generated to encode information for transmission to suitable receiver apparatus for execution by a data processing apparatus. The computer-storage medium can be a machine-readable storage device, a machine-readable storage substrate, a random or serial access memory device, or a combination of computer-storage mediums. 
     The terms “data processing apparatus,” “computer,” and “electronic computer device” (or equivalent as understood by one of ordinary skill in the art) refer to data processing hardware. For example, a data processing apparatus can encompass all kinds of apparatus, devices, and machines for processing data, including by way of example, a programmable processor, a computer, or multiple processors or computers. The apparatus can also include special purpose logic circuitry including, for example, a central processing unit (CPU), a field programmable gate array (FPGA), or an application-specific integrated circuit (ASIC). In some implementations, the data processing apparatus or special purpose logic circuitry (or a combination of the data processing apparatus or special purpose logic circuitry) can be hardware- or software-based (or a combination of both hardware- and software-based). The apparatus can optionally include code that creates an execution environment for computer programs, for example, code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of execution environments. The present disclosure contemplates the use of data processing apparatuses with or without conventional operating systems, for example LINUX, UNIX, WINDOWS, MAC OS, ANDROID, or IOS. 
     A computer program, which can also be referred to or described as a program, software, a software application, a module, a software module, a script, or code, can be written in any form of programming language. Programming languages can include, for example, compiled languages, interpreted languages, declarative languages, or procedural languages. Programs can be deployed in any form, including as stand-alone programs, modules, components, subroutines, or units for use in a computing environment. A computer program can, but need not, correspond to a file in a file system. A program can be stored in a portion of a file that holds other programs or data, for example, one or more scripts stored in a markup language document, in a single file dedicated to the program in question, or in multiple coordinated files storing one or more modules, sub-programs, or portions of code. A computer program can be deployed for execution on one computer or on multiple computers that are located, for example, at one site or distributed across multiple sites that are interconnected by a communication network. While portions of the programs illustrated in the various figures may be shown as individual modules that implement the various features and functionality through various objects, methods, or processes, the programs can instead include a number of sub-modules, third-party services, components, and libraries. Conversely, the features and functionality of various components can be combined into single components as appropriate. Thresholds used to make computational determinations can be statically, dynamically, or both statically and dynamically determined. 
     The methods, processes, or logic flows described in this specification can be performed by one or more programmable computers executing one or more computer programs to perform functions by operating on input data and generating output. The methods, processes, or logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, for example, a CPU, an FPGA, or an ASIC. 
     Computers suitable for the execution of a computer program can be based on one or more of general and special purpose microprocessors and other kinds of CPUs. The elements of a computer are a CPU for performing or executing instructions and one or more memory devices for storing instructions and data. Generally, a CPU can receive instructions and data from (and write data to) a memory. A computer can also include, or be operatively coupled to, one or more mass storage devices for storing data. In some implementations, a computer can receive data from, and transfer data to, the mass storage devices including, for example, magnetic, magneto-optical disks, or optical disks. Moreover, a computer can be embedded in another device, for example, a mobile telephone, a personal digital assistant (PDA), a mobile audio or video player, a game console, a global positioning system (GPS) receiver, or a portable storage device such as a universal serial bus (USB) flash drive. 
     Computer-readable media (transitory or non-transitory, as appropriate) suitable for storing computer program instructions and data can include all forms of permanent/non-permanent and volatile/non-volatile memory, media, and memory devices. Computer-readable media can include, for example, semiconductor memory devices such as random access memory (RAM), read-only memory (ROM), phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), and flash memory devices. Computer-readable media can also include, for example, magnetic devices such as tape, cartridges, cassettes, and internal/removable disks. Computer-readable media can also include magneto-optical disks and optical memory devices and technologies including, for example, digital video disc (DVD), CD-ROM, DVD+/−R, DVD-RAM, DVD-ROM, HD-DVD, and BLURAY. The memory can store various objects or data, including caches, classes, frameworks, applications, modules, backup data, jobs, web pages, web page templates, data structures, database tables, repositories, and dynamic information. Types of objects and data stored in memory can include parameters, variables, algorithms, instructions, rules, constraints, and references. Additionally, the memory can include logs, policies, security or access data, and reporting files. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry. 
     Implementations of the subject matter described in the present disclosure can be implemented on a computer having a display device for providing interaction with a user, including displaying information to (and receiving input from) the user. Types of display devices can include, for example, a cathode ray tube (CRT), a liquid crystal display (LCD), a light-emitting diode (LED), and a plasma monitor. Display devices can include a keyboard and pointing devices including, for example, a mouse, a trackball, or a trackpad. User input can also be provided to the computer through the use of a touchscreen, such as a tablet computer surface with pressure sensitivity or a multi-touch screen using capacitive or electric sensing. Other kinds of devices can be used to provide for interaction with a user, including to receive user feedback including, for example, sensory feedback including visual feedback, auditory feedback, or tactile feedback. Input from the user can be received in the form of acoustic, speech, or tactile input. In addition, a computer can interact with a user by sending documents to, and receiving documents from, a device that is used by the user. For example, the computer can send web pages to a web browser on a user&#39;s client device in response to requests received from the web browser. 
     The term “graphical user interface,” or “GUI,” can be used in the singular or the plural to describe one or more graphical user interfaces and each of the displays of a particular graphical user interface. Therefore, a GUI can represent any graphical user interface, including, but not limited to, a web browser, a touch screen, or a command line interface (CLI) that processes information and efficiently presents the information results to the user. In general, a GUI can include a plurality of user interface (UI) elements, some or all associated with a web browser, such as interactive fields, pull-down lists, and buttons. These and other UI elements can be related to or represent the functions of the web browser. 
     Implementations of the subject matter described in this specification can be implemented in a computing system that includes a back-end component, for example, as a data server, or that includes a middleware component, for example, an application server. Moreover, the computing system can include a front-end component, for example, a client computer having one or both of a graphical user interface or a Web browser through which a user can interact with the computer. The components of the system can be interconnected by any form or medium of wireline or wireless digital data communication (or a combination of data communication) in a communication network. Examples of communication networks include a local area network (LAN), a radio access network (RAN), a metropolitan area network (MAN), a wide area network (WAN), Worldwide Interoperability for Microwave Access (WIMAX), a wireless local area network (WLAN) (for example, using 802.11 a/b/g/n or 802.20 or a combination of protocols), all or a portion of the Internet, or any other communication system or systems at one or more locations (or a combination of communication networks). The network can communicate with, for example, Internet Protocol (IP) packets, frame relay frames, asynchronous transfer mode (ATM) cells, voice, video, data, or a combination of communication types between network addresses. 
     The computing system can include clients and servers. A client and server can generally be remote from each other and can typically interact through a communication network. The relationship of client and server can arise by virtue of computer programs running on the respective computers and having a client-server relationship. 
     Cluster file systems can be any file system type accessible from multiple servers for read and update. Locking or consistency tracking may not be necessary since the locking of exchange file system can be done at application layer. Furthermore, Unicode data files can be different from non-Unicode data files. 
     While this specification includes many specific implementation details, these should not be construed as limitations on the scope of what may be claimed, but rather as descriptions of features that may be specific to particular implementations. Certain features that are described in this specification in the context of separate implementations can also be implemented, in combination, in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations, separately, or in any suitable sub-combination. Moreover, although previously described features may be described as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can, in some cases, be excised from the combination, and the claimed combination may be directed to a sub-combination or variation of a sub-combination. 
     Particular implementations of the subject matter have been described. Other implementations, alterations, and permutations of the described implementations are within the scope of the following claims as will be apparent to those skilled in the art. While operations are depicted in the drawings or claims in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed (some operations may be considered optional), to achieve desirable results. In certain circumstances, multitasking or parallel processing (or a combination of multitasking and parallel processing) may be advantageous and performed as deemed appropriate. 
     Moreover, the separation or integration of various system modules and components in the previously described implementations should not be understood as requiring such separation or integration in all implementations, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products. 
     Accordingly, the previously described example implementations do not define or constrain the present disclosure. Other changes, substitutions, and alterations are also possible without departing from the spirit and scope of the present disclosure. 
     Furthermore, any claimed implementation is considered to be applicable to at least a computer-implemented method; a non-transitory, computer-readable medium storing computer-readable instructions to perform the computer-implemented method; and a computer system comprising a computer memory interoperably coupled with a hardware processor configured to perform the computer-implemented method or the instructions stored on the non-transitory, computer-readable medium. 
       FIG.  6    is a partial schematic perspective view of an example rig system  600  for drilling and producing a well. As shown in  FIG.  6   , the rig system  600  can communicate with the HCAS  100 . The well can extend from the surface through the Earth to one or more subterranean zones of interest. The example rig system  600  includes a drill floor  602  positioned above the surface, a wellhead  604 , a drill string assembly  606  supported by the rig structure, and a fluid circulation system  608  to filter used drilling fluid from the wellbore and provide clean drilling fluid to the drill string assembly  606 . For example, the example rig system  600  of  FIG.  6    is shown as a drill rig capable of performing a drilling operation with the rig system  600  supporting the drill string assembly  606  over a wellbore. The wellhead  604  can be used to support casing or other well components or equipment into the wellbore of the well. 
     The derrick or mast is a support framework mounted on the drill floor  602  and positioned over the wellbore to support the components of the drill string assembly  606  during drilling operations. A crown block  612  forms a longitudinally-fixed top of the derrick, and connects to a travelling block  614  with a drilling line including a set of wire ropes or cables. The crown block  612  and the travelling block  614  support the drill string assembly  606  via a swivel  616 , a kelly  618 , or a top drive system (not shown). Longitudinal movement of the travelling block  614  relative to the crown block  612  of the drill string assembly  606  acts to move the drill string assembly  606  longitudinally upward and downward. The swivel  616 , connected to and hung by the travelling block  614  and a rotary hook, allows free rotation of the drill string assembly  606  and provides a connection to a kelly hose  620 , which is a hose that flows drilling fluid from a drilling fluid supply of the circulation system  608  to the drill string assembly  606 . A standpipe  622  mounted on the drill floor  602  guides at least a portion of the kelly hose  620  to a location proximate to the drill string assembly  606 . The kelly  618  is a hexagonal device suspended from the swivel  616  and connected to a longitudinal top of the drill string assembly  606 , and the kelly  618  turns with the drill string assembly  606  as the rotary table  642  of the drill string assembly turns. 
     In the example rig system  600  of  FIG.  6   , the drill string assembly  606  is made up of drill pipes with a drill bit (not shown) at a longitudinally bottom end of the drill string. The drill pipe can include hollow steel piping, and the drill bit can include cutting tools, such as blades, dics, rollers, cutters, or a combination of these, to cut into the formation and form the wellbore. The drill bit rotates and penetrates through rock formations below the surface under the combined effect of axial load and rotation of the drill string assembly  606 . In some implementations, the kelly  618  and swivel  616  can be replaced by a top drive that allows the drill string assembly  606  to spin and drill. The wellhead assembly  604  can also include a drawworks  624  and a deadline anchor  626 , where the drawworks  624  includes a winch that acts as a hoisting system to reel the drilling line in and out to raise and lower the drill string assembly  606  by a fast line  625 . The deadline anchor  626  fixes the drilling line opposite the drawworks  624  by a deadline  627 , and can measure the suspended load (or hook load) on the rotary hook. The weight on bit (WOB) can be measured when the drill bit is at the bottom the wellbore. The wellhead assembly  604  also includes a blowout preventer  650  positioned at the surface of the well and below (but often connected to) the drill floor  602 . The blowout preventer  650  acts to prevent well blowouts caused by formation fluid entering the wellbore, displacing drilling fluid, and flowing to the surface at a pressure greater than atmospheric pressure. The blowout preventer  650  can close around (and in some instances, through) the drill string assembly  606  and seal off the space between the drill string and the wellbore wall. The blowout preventer  650  is described in more detail later. 
     During a drilling operation of the well, the circulation system  608  circulates drilling fluid from the wellbore to the drill string assembly  606 , filters used drilling fluid from the wellbore, and provides clean drilling fluid to the drill string assembly  606 . The example circulation system  608  includes a fluid pump  630  that fluidly connects to and provides drilling fluid to drill string assembly  606  via the kelly hose  620  and the standpipe  622 . The circulation system  608  also includes a flow-out line  632 , a shale shaker  634 , a settling pit  636 , and a suction pit  638 . In a drilling operation, the circulation system  608  pumps drilling fluid from the surface, through the drill string assembly  606 , out the drill bit and back up the annulus of the wellbore, where the annulus is the space between the drill pipe and the formation or casing. The density of the drilling fluid is intended to be greater than the formation pressures to prevent formation fluids from entering the annulus and flowing to the surface and less than the mechanical strength of the formation, as a greater density may fracture the formation, thereby creating a path for the drilling fluids to go into the formation. Apart from well control, drilling fluids can also cool the drill bit and lift rock cuttings from the drilled formation up the annulus and to the surface to be filtered out and treated before it is pumped down the drill string assembly  606  again. The drilling fluid returns in the annulus with rock cuttings and flows out to the flow-out line  632 , which connects to and provides the fluid to the shale shaker  634 . The flow line is an inclined pipe that directs the drilling fluid from the annulus to the shale shaker  634 . The shale shaker  634  includes a mesh-like surface to separate the coarse rock cuttings from the drilling fluid, and finer rock cuttings and drilling fluid then go through the settling pit  636  to the suction pit  636 . The circulation system  608  includes a mud hopper  640  into which materials (for example, to provide dispersion, rapid hydration, and uniform mixing) can be introduced to the circulation system  608 . The fluid pump  630  cycles the drilling fluid up the standpipe  622  through the swivel  616  and back into the drill string assembly  606  to go back into the well. 
     The example wellhead assembly  604  can take a variety of forms and include a number of different components. For example, the wellhead assembly  604  can include additional or different components than the example shown in  FIG.  6   . Similarly, the circulation system  608  can include additional or different components than the example shown in  FIG.  6   . 
     While this specification contains many specific implementation details, these should not be construed as limitations on the scope of what may be claimed, but rather as descriptions of features that may be specific to particular implementations. Certain features that are described in this specification in the context of separate implementations can also be implemented, in combination, in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations, separately, or in any suitable sub-combination. Moreover, although previously described features may be described as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can, in some cases, be excised from the combination, and the claimed combination may be directed to a sub-combination or variation of a sub-combination. 
     Particular implementations of the subject matter have been described. Other implementations, alterations, and permutations of the described implementations are within the scope of the following claims as will be apparent to those skilled in the art. While operations are depicted in the drawings or claims in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed (some operations may be considered optional), to achieve desirable results. In certain circumstances, multitasking or parallel processing (or a combination of multitasking and parallel processing) may be advantageous and performed as deemed appropriate. 
     Moreover, the separation or integration of various system modules and components in the previously described implementations should not be understood as requiring such separation or integration in all implementations, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products. 
     Accordingly, the previously described example implementations do not define or constrain the present disclosure. Other changes, substitutions, and alterations are also possible without departing from the spirit and scope of the present disclosure. 
     Furthermore, any claimed implementation is considered to be applicable to at least a computer-implemented method; a non-transitory, computer-readable medium storing computer-readable instructions to perform the computer-implemented method; and a computer system comprising a computer memory interoperably coupled with a hardware processor configured to perform the computer-implemented method or the instructions stored on the non-transitory, computer-readable medium. 
     A number of embodiments of the present disclosure have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the present disclosure. Accordingly, other embodiments are within the scope of the following claims. 
     Various modifications, alterations, and permutations of the disclosed implementations can be made and will be readily apparent to those of ordinary skill in the art, and the general principles defined may be applied to other implementations and applications, without departing from scope of the disclosure. In some instances, details unnecessary to obtain an understanding of the described subject matter may be omitted so as to not obscure one or more described implementations with unnecessary detail and inasmuch as such details are within the skill of one of ordinary skill in the art. The present disclosure is not intended to be limited to the described or illustrated implementations, but to be accorded the widest scope consistent with the described principles and features.