Patent Publication Number: US-11047180-B2

Title: Downhole hole cleaning joints and method of using same

Description:
BACKGROUND 
     This present disclosure relates generally to techniques for performing wellsite operations. More specifically, the present disclosure relates to tubulars, such as drill strings and drill stem components, used in downhole operations. 
     Oilfield operations may be performed to locate and gather valuable downhole fluids. Oil rigs are positioned at wellsites, and downhole equipment, such as a drilling tool, is deployed into the ground by a drill string to reach subsurface reservoirs. At the surface, a drilling rig is provided to deploy stands of drill pipe into the wellbore to form the drill string. A drill bit is mounted on the lower end of the drill string, and advanced into the earth from the surface to form a wellbore. 
     Various surface equipment, such as tongs, a top drive, a Kelly and a rotating table, may be used to threadedly connect the stands of pipe (e.g., drill pipe) together, and to apply torque to the stands of drill pipe and the drill bit. A mud pit may be located at the surface for passing drilling mud through the drill string to cool the drill bit and carry away cuttings. 
     The drill string may be provided with various downhole components, such as a bottom hole assembly (BHA), measurement while drilling, logging while drilling, telemetry and other downhole tools, to perform various downhole operations, such as providing power to the drill bit to drill the wellbore and perform downhole measurements. 
     Various downhole devices, such as stabilizers, have been provided along the drill string. Examples of downhole devices are provided in U.S. Pat. Nos. 4,610,316, 4,000,549, and RE37167. 
     SUMMARY 
     In at least one aspect, the disclosure relates to a hole cleaning joint for a drill string deployable into a wellbore penetrating a subterranean formation. The hole cleaning joint includes a tubular body connectable to the drill string and a hole cleaning section. The hole cleaning section is positionable about the tubular body, and has an outer surface engageable with a wall of the wellbore. The outer surface has spiral grooves extending therein defining blades therebetween. The spiral grooves may have an uphole end and a downhole end with a spiral cavity therebetween. At least a portion of the spiral cavity may have a width that decreases towards the uphole end of the spiral cavity to define a tapered flow channel to receive cuttings therethrough whereby uphole movement of cuttings is facilitated during drilling. 
     The hole cleaning joint may also include a connector at at least one end of the tubular body. The connector may be at least one of a sleeve, a coupling, an internal thread, a threaded end, a ring, a pin end, and/or a box end. A cross-section of the hole cleaning section has a pinwheel shape defined by a plurality of the blades with a plurality of spiral grooves therebetween. 
     The spiral grooves have a sloped portion and an inclined portion therein having a localized agitation area therein. The spiral grooves may include a pair of mirrored grooves, and/or an uphole portion, an intermediate portion, and a downhole portion with peripheral depressions therebetween. The spiral grooves have multiple pitches. The multiple pitches may include a first pitch and a second pitch, with the first pitch greater than the second pitch. 
     The hole cleaning joint may also include at least one ring. The at least one end of the hole cleaning section may terminate at the at least one ring. A diameter of the hole cleaning section may taper to the at least one ring. The spiral grooves may have a helical shape and/or be oriented in the direction of rotation. 
     A portion of the width of the spiral grooves may increase between the uphole and downhole ends thereof. The spiral groove may narrows at a location between the uphole end and the downhole end thereof. The hole cleaning section may have an end operatively connectable to a connector. The hole cleaning section may have the tubular body at one end thereof and a connector at an opposite end thereof. 
     The hole cleaning section may have an outer diameter that reduces or increases from an uphole end and to a downhole end thereof. An outer diameter of the hole cleaning section may be greater than or the same as an outer diameter of the tubular body. The hole cleaning section may be integral or modular with respect to the pipe body. The hole cleaning section may be weldable to at least one of the tubular body and/or at least one connector. The hole cleaning section may include a plurality of hole cleaning sections with at least one of the tubular bodies therebetween. 
     The spiral grooves may have an angle, width, depth, pitch, and orientation to facilitate flow of the cuttings uphole through the flow channel. The hole cleaning section may a defined outer diameter, shape, length, and orientation to facilitate flow of the cuttings uphole through the flow channel. 
     In another aspect, the disclosure relates to a hole cleaning system for drilling a wellbore penetrating a subterranean formation. The system includes a drill string deployable from a rig, a bottomhole assembly carried by the drill string, and a hole cleaning joint. The hole cleaning joint includes a tubular body connectable to the drill string, and a hole cleaning section positionable about the tubular body. The hole cleaning section has an outer surface engageable with a wall of the wellbore and spiral grooves extending therein defining blades therebetween. The spiral grooves have an uphole end and a downhole end with a spiral cavity therebetween. At least a portion of the spiral cavity having a width that decreases towards the uphole end of the spiral cavity to define a tapered flow channel to receive cuttings therethrough whereby uphole movement of cuttings is facilitated during drilling. 
     The drill string may include at least one tubular and at least one of the hole cleaning joints. The tubular may include at least one of a drill pipe, drill collars, heavy weight drill pipe, sleeve, and/or collar. The drill string may include pairs of drill pipe and a plurality of hole cleaning joints. One of the plurality of hole cleaning joints may be operatively connected to each pair of drill pipe of the drill string. The hole cleaning joint may include a plurality of the hole cleaning sections connected to at least one of the tubular bodies. The hole cleaning joint may include connectors at each end thereof matably connectable connectors of an adjacent hole cleaning joint to form at least a portion of the drill string. 
     In yet another aspect, the disclosure relates to a method of drilling a wellbore penetrating a subterranean formation. The method involves deploying a downhole tool from a rig via a drill string and operatively connecting at least one hole cleaning joint to the drill string. The hole cleaning joint have a hole cleaning section with spiral grooves extending into an outer surface thereof. The spiral grooves have a width that decreases towards an uphole end thereof to define a tapered flow channel therethrough. The method further involves generating cuttings by advancing a downhole tool into the subterranean formation via the drill string, facilitating flow of the cuttings to the surface by passing a drilling fluid through the drill string and up an annulus between the drill string and a wall of the wellbore such that at least a portion of the cuttings pass through the tapered flow channel of the spiral grooves. 
     The method may also involve agitating the cuttings in the flow channel. The operatively connecting may involve operatively connecting the at least one hole cleaning joint and at least one tubular to the drill string. The method may also involve engaging a wall of the wellbore with at least a portion of the hole cleaning joint. 
     Finally in another aspect, the disclosure relates to a hole cleaning joint for a drill string deployable into a wellbore penetrating a subterranean formation. The hole cleaning joint includes a tubular body connectable to the drill string and a hole cleaning section positionable about the tubular body. The hole cleaning section has an outer surface engageable with a wall of the wellbore, and spiral grooves extending therein defining blades therebetween. The spiral grooves have an uphole end and a downhole end with a spiral cavity therebetween. The spiral cavity has a sloped portion and an inclined portion with an obtuse angle therebetween defining a localized agitation area therein whereby uphole movement of cuttings is facilitated during drilling. 
     A cross-section of the hole cleaning section may have a pinwheel shape. The pinwheel shape may be defined by a plurality of the blades with a plurality of spiral grooves therebetween. A depth of the spiral grooves may increase between the sloped portion and the inclined portion. The spiral grooves may have a rounded corner between the sloped portion and the inclined portion. The spiral grooves may have a helical shape. The spiral grooves may be oriented in the direction of rotation. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the above recited features and advantages of the present disclosure can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof that are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate example embodiments and are, therefore, not to be considered limiting of its scope. The figures are not necessarily to scale and certain features, and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness. 
         FIG. 1  depicts a schematic view, partially in cross-section, of a wellsite having a rig with a drill string advanced into a wellbore, the drill string including hole cleaning joints. 
         FIG. 2A  depicts another schematic view, partially in cross-section, of a wellsite having a rig with a drill string advanced into the wellbore, the drill string including hole cleaning joints.  FIG. 2B  depicts a portion  2 B of the drill string of  FIG. 2A . 
         FIGS. 3A-3B  depict plan and cross-sectional views, respectively, of a portion of a hole cleaning joint including a hole cleaning pad with a spiral hole cleaning section. 
         FIGS. 4A-4B  depict plan and perspective views, respectively, of a portion of a hole cleaning joint including a hole cleaning pad with a segmented spiral hole cleaning section. 
         FIGS. 5A-5B  depict plan and perspective views, respectively, of a portion of a hole cleaning joint including a hole cleaning pad with a dual spiral hole cleaning section. 
         FIGS. 6A-6B  depict plan and perspective views, respectively, of portions of adjacent hole cleaning joints including a hole cleaning pad with a variable spiral hole cleaning section. 
         FIGS. 7A-7B  depict plan and perspective views, respectively, of a portion of a hole cleaning joint including a hole cleaning pad with a mixed pitch spiral hole cleaning section. 
         FIG. 8  depicts a plan view of a hole cleaning joint including multiple hole cleaning sections with mixed pitch spiral hole cleaning sections. 
         FIGS. 9A-9B, 10A-10B, 11A-11B, 12A-12B  depict perspective views of various configurations of hole cleaning joints including multiple hole cleaning sections with tapered, mixed pitch, spiral hole cleaning sections. 
         FIG. 13  is a flow chart depicting a method of drilling a wellbore. 
     
    
    
     DETAILED DESCRIPTION 
     The description that follows includes exemplary apparatuses, methods, techniques, and/or instruction sequences that embody techniques of the present subject matter. However, it is understood that the described embodiments may be practiced without these specific details. 
     The present disclosure relates to hole cleaning joints positionable along a drill string to facilitate removal of cuttings during drilling. The hole cleaning joints may be connectable to (or integral with) various tubulars, such as drill pipe, drill collars, heavy weight drill pipe (HWDP), other joints, sleeves, collars, and drilling components, to drive a drill bit and to form the drill string for the passage of fluid (e.g., drilling mud) therethrough. The hole cleaning joints may be drill pipe or other joints and/or tubulars including hole cleaning pads (or wear pad) having hole cleaning sections with spiral grooves of various geometries (e.g., depths, widths, angles, pitches, and/or orientations). 
     Various configurations of one or more hole cleaning pads, hole cleaning sections, and/or other joints (or components) may be combined to form hole cleaning joints along the drill string. Various shapes and configurations of the hole cleaning joints, hole cleaning pads, and/or hole cleaning sections with grooves therein may be used, for example, to facilitate uphole movement of cuttings, optimize cuttings removal, perform hole cleaning, minimize differential sticking tendencies, reduce borehole friction, and/or enhance drilling efficiency. 
       FIG. 1  is a schematic view of an example environment in which joints with hole cleaning capabilities may be used. While a land-based drilling rig with a specific configuration is depicted, the hole cleaning joints provided herein may be usable with all types of drilling operations (e.g., land or offshore applications). The hole cleaning joints provided herein may be used with all drilling applications, including high-angle directional drilling, horizontal drilling, extended reach drilling (ERD), and/or other critical drilling applications, among others. 
       FIG. 1  shows a wellsite  100  including a rig  101  for performing various wellbore operations, such as drilling. A drill string  103  with bit  104  at a downhole end thereof is advanced into the formation  105  to form wellbore  106 . Various rig equipment  107 , such as a Kelly, rotary table, top drive, elevator, etc., may be provided at the rig  101  to support and/or drive the drill string  103 . 
     A bottom hole assembly (BHA)  108  is at a lower end of the drill string  103  and contains various downhole components for performing downhole operations. The components may include, for example, measurement while drilling, logging while drilling, telemetry, processors and/or other downhole tools. A driver, such as a downhole motor or rotary steerable system,  109  may also be provided uphole of the bit  104  for rotationally driving the bit  104 . The drill string  103  includes a plurality of drill pipe joints  115  and hole cleaning joints  111 . 
     A mud pit  110  may be provided at the surface for passing mud through the drill string  103 , the BHA  108  and out the bit  104  as indicated by the arrows. Cuttings may be returned to the surface through an annulus  114  between the drill string  103  and a wall of the wellbore  106  as also indicated by arrows. A surface controller  112  is also provided at the surface to operate the wellsite  100 . As shown, the BHA  108  may optionally include a downhole controller  112  for communication between the BHA  108  and the surface controller  112 . One or more controllers  112  may be provided. 
       FIG. 2A  shows another schematic view of a wellsite  200  including a drilling rig  201  with a drill bit  204  advanced into a formation  205  by a drill string  203  (shown in detail in  FIG. 2B ) to form a wellbore  206 . The drill string  203  includes multiple drill pipe joints  215  and multiple hole cleaning joints  211  connected end to end to form a drill string  203 . As shown in the detailed portion  2 B, the drill string  203  includes multiple drill pipe joints  215  followed by one hole cleaning joint  211 . One or more hole cleaning joints  211  may be provided about one or more drill pipe joints  215  within the drill string  203 . This example depicts that one of every three joints is a hole cleaning joint  211 . 
     The hole cleaning joints  211  herein may be used alone or connected to adjacent tubulars, such as drill pipe joints  215 , using a variety of connections to form drill string  203 . Ends (or connections)  212   a,b  of the hole cleaning joint  211  may be threadedly connectable to adjacent tubulars, such as the drill pipe joint  215 . In some cases, the hole cleaning joints  211  may include connectors (or connection means) that are integrally formed therewith and/or operatively connected thereto for providing the desired connections to adjacent tubulars. Examples of connectors may include sleeves, couplings, internal threads, threaded ends, pin ends and/or box ends, among others. 
     In the example shown, the hole cleaning joints  211  have the same pin and box type ends  212   a,b  for connection to conventional drill pipe joints. While the hole cleaning joints  211  of  FIGS. 2A and 2B  are shown connected to drill pipe joint  215 , the hole cleaning joints  211  may be connected to adjacent tubulars that may be one or more of another (same or different) hole cleaning joint (e.g.,  211 ), drill pipe joint (e.g.,  215 ), and/or other tubulars. 
     The hole cleaning joints  211  may be any tubular, such as a drill pipe joint (e.g.,  215 ), HWDP, and/or other tubulars. The hole cleaning joints  211  may include, for example, pin and box ends  212   a,b  with a pipe (or tubular) body  222  therebetween and a hole cleaning pad  220  along the pipe body  222 . The hole cleaning pad  220  may be formed integrally with or operatively connected (e.g., by friction welding) to the pipe body  222 . The hole cleaning sections  220  may be welded about the pipe body  222  between either or both ends  212   a,b.    
     The hole cleaning pad  220  may have a hole cleaning section  216  provided with grooves  218  extending therein. The hole cleaning section  216  may have customized grooves  218  formed on the hole cleaning pad  220  between portions of the pipe body  222 . For example, the grooves  218  may be machined into wear pad  220  on the pipe body  222  by cutting the grooves  218  into the hole cleaning pad  220 . Another option is to machine customized spirals on an extended tool joint to make the pipe body  222  and the hole cleaning pad  220  an integral part. The grooves  218  and/or hole cleaning joints  211  may have profiles and geometries to address various hole cleaning issues confronted at the wellsite  200 . 
     The hole cleaning joints  211  may be customized to promote hole cleaning in different well drilling conditions and/or to address various hole cleaning issues confronted in the well. The hole cleaning joints  211  may be customized, for example, by varying the geometry of the spiraled grooves  218  (e.g., angle, width, depth, pitch, orientation, and/or other dimensions) and/or hole cleaning section  220  (e.g., diameter, shape, length, orientation, and/or other dimensions). The geometry of the hole cleaning section  216  may be customized to optimize hole cleaning by gathering cuttings, accelerating cuttings to move up the wellbore  206 , and/or enhancing cuttings dispersal throughout and up the well bore  206  as indicated by the arrows. 
     Variable, customized spiraled grooves  218  distributed throughout the drill string  203  may be used, for example, to provide comprehensive reduction in differential sticking tendencies for the drill string  203 . For example, an angle (e.g., pitch) of the spiral grooves  218  may be varied to promote hole cleaning by facilitating cuttings pickup from downhole locations. The angle may also be used to increase annular velocity and dispersion of the cuttings towards the surface and to optimize thrust according to hole size and fluid velocity. The spiraled grooves may be oriented at an angle in the direction of rotation (e.g., clockwise for clockwise rotation). In another example, a shape of the grooves  218  may be used to facilitate hole cleaning by facilitating the removal of cuttings and reducing differential sticking tendencies by reducing contact area between the drill string  203  and a wall of the wellbore  206 . 
     The hole cleaning pad  220  may have selected outside diameters to further customize and optimize the hole cleaning properties. Transitions between the hole cleaning pad  220  and other portions of the pipe body  222  and/or adjacent tubulars (e.g., drill pipe joint  215 ) having different diameters may be customizable. A gradual transition may be provided, for example, on a downhole (or leading) end of the hole cleaning section  216  to optimize accumulation or gathering of cuttings. A steep transition from the outer diameter of the hole cleaning pad  220  to the outer diameter of the pipe body  222  on an uphole (or trailing) portion of the hole cleaning section  218  may be used to promote dispersion of cuttings up the well bore  203 . Variations and unique transitions (e.g., depressions and/or raised portions) may also be incorporated along various portions of the hole cleaning joint  211  to alter drilling fluid and cutting flow patterns for more favorable hole cleaning capabilities. 
     In some cases, the drill string  203  may be deployed through a wellsite component, such as a blowout preventer (e.g., an annular blowout preventer) positioned about a wellbore  206 . The blades between grooves  218  of the hole cleaning joint  211  may be, for example, rounded and/or smoothed (e.g., along edges of the blades) to prevent damage to the blowout preventer (e.g., blades of the blowout preventer) that may be engaged when the drill string  203  is tripping into or out of the wellbore  206 . 
       FIGS. 3A-12B  depict various configurations of hole cleaning joints  311 - 1211 . As depicted in these views, various geometries of the hole cleaning joints, hole cleaning pads, hole cleaning sections, and/or grooves may be provided. 
       FIGS. 3A and 3B  show a portion of a hole cleaning joint  311  with a hole cleaning section  316  having a spiral configuration.  FIG. 3A  shows a plan view of a portion of the hole cleaning joint  311 .  FIG. 3B  shows a cross-sectional view of the hole cleaning joint  311  taken along line  3 B- 3 B. The portion of the hole cleaning joint  311  may be similar to the hole cleaning joint  211  of  FIGS. 2A and 2B , except that the ends are not shown and a specific configuration of a hole cleaning section  316  is depicted. Pin and box ends (e.g.,  212   a,b  of  FIG. 2A,2B ) may be provided for connection of the hole cleaning joint  311  to adjacent tubulars. 
     The hole cleaning joint  311  includes a pipe body (or body upset)  322  and a hole cleaning pad  320 . The hole cleaning pad  320  includes tapered ends  323   a,b  with the hole cleaning section  316  therebetween. The hole cleaning pad  320  may be positioned between portions of the pipe body  322  or formed integrally therewith. The hole cleaning section  316  has spiral grooves  318  extending therein. The hole cleaning pad  320  has a maximum outer diameter OD 1  along a portion of the hole cleaning section  316 . The OD 1  reduces along the tapered ends  323   a,b  until it reaches the pipe body  322 . The pipe body has an outer diameter OD 2  that is less than the outer diameter OD 1 . 
     The hole cleaning section  316  also has an outer surface  324  with the spiral grooves  318  extending therein. Multiple spiral grooves  318  of similar shape are shown positioned about the outer surface  324 . The spiral grooves  318  may extend helically along a length of the hole cleaning section  316  between the tapered ends  323   a,b . The multiple spiral grooves  318  are shown as having identical dimension (e.g., angle, width, depth, pitch, orientation, and/or other dimensions). The grooves  318  have a maximum width Wmax and depth D 1  that tapers at each of the hole cleaning sections  316  and terminates at each tapered end  323   a,b  in a tapered, rounded point. 
     As shown by the cross-sectional view of  FIG. 3B , each groove  318  may extend a distance into the outer surface  324  to define a sloped portion  326  and an inclined portion  328  with a rounded corner therebetween  330 . The cross-sectional view shows the grooves  318  at a maximum depth D 1  along section  3 B- 3 B. The grooves  318  are shown as having an obtuse angle defined by angles A 1 , A 2  as shown. A blade  332  is defined between each groove  318 . The combination of blades  332  and grooves  318  creates a cross-section in the shape of a pinwheel. This pinwheel shape may be used to facilitate circulation to lift cuttings by generating localized agitation as indicated by the curved arrow within the groove  318 . 
       FIGS. 4A and 4B  show a portion of a hole cleaning joint  411  including a hole cleaning pad  420  with a hole cleaning section  416  having a segmented spiral configuration. As shown by this view, the hole cleaning section  416  may be similar to the hole cleaning section  316 , except that the hole cleaning pad  420  has a different size and shape and the grooves  418   a - c  have a different configuration. The hole cleaning pad  420  has tapered ends  423   a,b  that extend from the hole cleaning section  416  to a pipe body  422 . 
     In this version, the hole cleaning section  416  has grooves  418   a - c  disposed about an outer surface  424  of the hole cleaning section  416 . As shown in this view, the grooves  418   a,b  are in a three-tier configuration with three rows of angled grooves  418   a - c  separated by a two peripheral depressions  434 . The rows of angled grooves  418   a,b,c  include an uphole row of grooves  418   a , an intermediate row of grooves  418   b , and a downhole row of grooves  418   c  separated by the peripheral depressions  434 . 
     The uphole and downhole rows of grooves  418   a,c  have similar configurations having curved grooves extending into the hole cleaning section  416 . The intermediate row of grooves  418   b  also extend into the hole cleaning section  416 , but have a shorter length than the grooves  418   a,c . The angled grooves  418   a,b,c  are spirally aligned about the hole cleaning section  416  to form pairs  436   a,b  of dual spirals about the hole cleaning section  416  as indicated by dashed lines. The pairs of dual spirals  436   a,b  include mirrored individual spirals  436   a,b  touching on adjacent sides. 
       FIGS. 5A and 5B  show a portion of a hole cleaning joint  511  including a hole cleaning pad  520  with a hole cleaning section  516  having a dual spiral configuration. As shown by this view, the hole cleaning joint  511  may be similar to the hole cleaning joint  311 , except that the hole cleaning section  516  and grooves  518   a - d  have a different configuration. As demonstrated by  FIGS. 5A and 5B , the hole cleaning section  516  may be provided with the spiral grooves  518   a - d  having different dimensions, and one or more sets  536   a,b  of the spiral grooves  518   a - d  may be provided. Some of the grooves  518   a - d  may have continuous width and depth, and some may have varied widths and depths. 
     In this version, the hole cleaning section  516  has a plurality of grooves  518   a - d  disposed about an outer surface  524  of the hole cleaning section  516 . Each of the sets of grooves  536   a,b  are the same, with each of the individual grooves  518   a - d  having different dimensions. Grooves  518   a - c  each have the variable depths and variable widths Wa-c with a constant pitches P. Groove  518   d  has a first portion  538   a  with a first Wd 1  and a second portion  538   b  with a second width Wd 2 . The outer surface  524  of the hole cleaning section  516  has a constant diameter terminating at ends  512   a,b.    
     As shown in this view, two sets  536   a,b  of the grooves  518   a - d  extend along the hole cleaning section  516  separated by a peripheral ring  537 . An uphole set  536   a  of the spiral grooves  518   a - d  extends between an uphole end  512   a  and the ring  537 . A downhole set  536   b  of the spiral grooves  518   a - d  extends between the ring  537  and a downhole end  512   b . The ring(s)  537  may define a bearing portion contactable with the wellbore wall. The hole cleaning section  516  terminates at the downhole end  512   b  and the uphole end  512   a  for connection to other devices (not shown), such as an end (e.g.,  212   a,b  of  FIG. 2A,2B ) or a pipe body (e.g.,  222  of  FIG. 2 ). Additional ring(s)  537  may also be provided along the hole cleaning pad  520  and/or connected to another device (not shown), such as an end (e.g.,  212   a,b  of  FIG. 2 ) or a pipe body (e.g.,  222  of  FIGS. 2A,2B ). 
       FIGS. 6A and 6B  show portions of two adjacent joints  611   a,b . The adjacent joints  611   a,b  may both be hole cleaning joints. In some cases,  611  may refer to a drill pipe joint, such as the drill pipe joint  215  of  FIGS. 2A,2B . A portion of joint  611   a  is depicted as being connected to a portion of the adjacent hole cleaning joint  611   b . The portion of the hole cleaning joint  611   a  includes an end  612   b  (e.g., pin end  212   b  of  FIGS. 2A, 2B ) connectable to the hole cleaning joint  611   b . The hole cleaning joint  611   b  is depicted as including an end  612   a  (e.g., box end  212   a  of  FIGS. 2A,2B ) connectable to the end  612   b . The hole cleaning section  616  terminates at a ring  637  at an end of the hole cleaning joint  611   b  opposite end  612   a . The hole cleaning joints  611   a,b  may connect to a pipe portion (not shown, such as pipe body  222  of  FIGS. 2A, 2B ). 
     The hole cleaning joint  611   b  also includes a hole cleaning pad  620  with a hole cleaning section  616  having a single spiral configuration. The hole cleaning section  616  may be the same as the hole cleaning sections  536   b  of  FIG. 5 , except with a different groove configuration. As demonstrated by  FIGS. 6A and 6B , the hole cleaning section  616  has a plurality of grooves  618  disposed about an outer surface  624  of the hole cleaning section  616 . Each of the grooves  618  has a varied width and depth therealong. Grooves  618  have a width W 2  at each end thereof with a narrowed width W 1  therebetween. The grooves  618  narrow along an area N along each groove  618 . 
     As also shown by  FIGS. 6A and 6B , the outer surface  624  of the hole cleaning section  616  may taper. In the example shown, an outer diameter of the hole cleaning section  616  reduces from a downhole end towards end  612   a  uphole therefrom. 
       FIGS. 7A and 7B  show a portion of a hole cleaning joint  711  including a hole cleaning pad  720  having a hole cleaning section  716  with a mixed pitch spiral configuration. As shown by this view, the hole cleaning section  716  may be similar to the hole cleaning section  516  ( FIG. 5 ), except that the hole cleaning pad  720  and grooves  718  have a different configuration. The hole cleaning pad  720  has grooves  718  extending therein and terminating at rings  737 . The hole cleaning pad  720  may optionally taper from a larger uphole end to a smaller downhole end (or vice versa). As also shown in this version, the rings  737  are integrally formed with the hole cleaning section  716 . 
     As demonstrated by  FIGS. 7A and 7B , the hole cleaning joint  711  may include grooves  718  with varied width, depth and pitches P 1  and P 2  extending along a length of the hole cleaning section  716 . In this version, the hole cleaning section  716  has a plurality of grooves  718  disposed about an outer surface  724  of the hole cleaning section  716 . As shown in this view, each of the grooves  718  has a first pitch P 1  and a first width W 1  along a first portion A of the hole cleaning section  716 , and a second pitch P 2  and a second width W 2  along a second portion B of the hole cleaning section. The pitch P 1  is shallower than the pitch P 2 , and the width W 2  is greater than width W 1 . In some cases, the depth and width of the grooves  718  may be constant along the length of the hole cleaning section  716 . 
     The varied pitches P 1 , P 2  are at angles that may be used to provide deeper and wider spiral grooves towards a downhole (or leading) end of the hole cleaning joint  711 . The profile of the grooves  718  may become shallower and narrower as the grooves  718  progress uphole along the hole cleaning section  716 . This configuration may be used to encourage gathering of cuttings as the hole cleaning joint  711  enters a new section of the wellbore to be cleared of cuttings. 
     The size and volume of the grooves  718  may decrease toward an uphole end of the hole cleaning section  716 . As the cuttings move upwards about the hole cleaning section  716 , a velocity of the cuttings may be accelerated, propelling the cuttings up and out of the wellbore at an increasing rate. The grooves  718  may gradually become shallower and narrower to accelerate movement of the cuttings and/or the flow of drilling fluid. 
     Toward the downhole end of the hole cleaning section  716 , a profile of the grooves  718  may also have an increased width and depth to promote dispersion of the cuttings and/or to prevent accumulation on a downhole side of the wellbore, for example, along obstructions in the wellbore (e.g., as ledges, key seats, tight spots and washed out sections of the wellbore). 
       FIGS. 8-12B  show various configurations of hole cleaning joints  811 - 1211  including various combinations of hole cleaning pads  820 - 920  and pipe bodies  822 - 922 . The hole cleaning joints may include various combinations of one or more hole cleaning sections with various hole cleaning sections  816 - 916  having various groove geometries to address different hole cleaning challenges that might be encountered during drilling operations. 
       FIG. 8  shows a hole cleaning joint  811  including multiple hole cleaning pads  820 . The hole cleaning pads  820  include hole cleaning sections  816  in a mixed pitch spiral configuration. The hole cleaning joint  811  includes connections with pin and box ends  812   a,b  at each end thereof with multiple hole cleaning sections  816  and pipe bodies  822  therebetween. 
     The box end  812   a  and a pin end  812   b  are at each end of the hole cleaning joint  811  for connection to an adjacent tubular (e.g., drill pipe joint  215  of  FIGS. 2A, 2B ). The box end  812   a  and the pin end  812   b  may be operatively connectable to or integral with the pipe bodies  822  adjacent thereto. While different ends  812   a,b  are depicted, similar ends may optionally be provided. 
     As shown, three identical hole cleaning sections  816  are provided between the tubular connections  812   a,b  with pipe bodies  822  therebetween. The hole cleaning joints  811  may include one or more of the same or different hole cleaning pads  820  and/or hole cleaning sections  816 . Each of the hole cleaning sections  816  may have a mixed pitch spiral configuration similar to the hole cleaning section  716  of  FIG. 7A  or another configuration. 
     The hole cleaning joint  811  may have various diameters along the outer surface thereof to facilitate removal of cuttings. For example, hole cleaning sections  816  may have an overall outer diameter of OD 8   a . The hole cleaning section  816  may have a tapered outer surface  824  that tapers away from a central portion of the hole cleaning section  816  to the pipe bodies  822  on either side thereof. The pipe bodies  822  may have a reduced diameter OD 8   b . The pin and box ends  812   a,b  may have an outer diameter similar to the outer diameter OD 8   a.    
       FIGS. 9A-12B  show configurations of a hole cleaning joints  911 - 1211  having multiple hole cleaning pads  920  having tapered hole cleaning sections  916  in a tapered mixed pitch spiral configuration.  FIG. 9A  shows a hole cleaning joint  911  including ends  912   a,b  with three tapered hole cleaning sections  916  and two pipe bodies  922  therebetween. Each of the hole cleaning pads  920  has identical tapered hole cleaning sections  916  with grooves  918  in a tapered mixed pitch spiral configuration.  FIG. 9B  shows an alternate view with a length of the pipe bodies  922  as shown reduced. 
     As shown in  FIG. 9A , the three hole cleaning sections  916  are the same, but optionally could be different. The hole cleaning sections  916  may be similar to the sections  816  of  FIG. 8  with grooves  918  in a mixed pitch spiral configuration. In this version, the hole cleaning section  916  has a tapered outer surface  924  that extends from a maximum outer diameter OD 9   a  at an uphole end to a smaller diameter OD 9   b  at the pipe body  922  at a downhole end thereof. As shown by lines  919 , the hole cleaning joint  911  may be include one or more modular hole cleaning sections  911  or other components that may optionally be attached, for example, by welding. 
     The hole cleaning joint  911  may have various diameters along the outer surface  924  thereof to facilitate removal of cuttings. For example, the hole cleaning joint  911  may have an overall outer diameter of OD 9   a . A reduced diameter OD 9   b  may be provided along portions of the hole cleaning assembly  914 , such as along the pipe bodies  922  and/or ends  912   a,b . A reduced diameter may also be provided along the tapered outer surface  924  of the hole cleaning sections  916 . 
       FIGS. 10A and 10B  show an alternate version of the hole cleaning joint  1011 . As shown in  FIG. 10A , this version is the same as the hole cleaning joint  911 , except that the ends  912   a,b  have two hole cleaning sections  916  and a single pipe body  922  therebetween, and that an outer diameter OD 10  of the end  912   a  is greater than the outer diameter OD 9   b  of the tapered hole cleaning tool section  916 .  FIG. 10B  shows the hole cleaning joint  1011  with the pipe body  922  reduced. 
       FIGS. 11A and 11B  show another alternate hole cleaning joint  1111 . As shown in  FIG. 11A , this version is the same as the hole cleaning joint  911 , except that the ends  912   a,b  have one hole cleaning pad  920  with one hole cleaning section  916  and a single pipe body  922  therebetween. The hole cleaning section  916  is positioned uphole from the single pipe body  922 .  FIG. 11B  shows the hole cleaning joint  1111  with the pipe body  922  reduced and end  912   b  removed. 
       FIGS. 12A and 12B  show another alternate hole cleaning joint  1211 . As shown in  FIG. 12A , this version is the same as the hole cleaning joint  911  of  FIG. 11 , except that the ends  912   a,b  have one hole cleaning pad  920  with one hole cleaning section  916  and a single pipe body  922  in a different order therebetween. The hole cleaning section  916  is positioned downhole from the single pipe body  922 .  FIG. 12B  shows the hole cleaning joint  1211  with the pipe body  922  reduced and end  912   a  removed. 
     When forming the various hole cleaning pads and/or joints herein, portions of the tubular may be formed, for example, by welding the hole cleaning section to the downhole end of the hole cleaning joint just above the downhole connector (e.g., pin or box end) as shown, for example in  FIG. 12A . In another example, the hole cleaning section may be welded a distance (e.g., about 144″ (3.66 m) from an uphole end of the uphole connector (e.g., pin or box end) of the hole cleaning joint. An example is shown in  FIG. 9A  by lines  919  indicating joining of portions of the tubular. 
     The hole cleaning section position may be optimized at a distance, for example far enough from the downhole connector to perform the desired hole cleaning. The hole cleaning section may be as close to the downhole end as possible to reduce the weight and size of the hole cleaning joint and/or be long enough to create a hydraulic actuation to release fluid on a downhole side of the drillstring. The spiral shape of the grooves along the hole cleaning section may be at an angle (e.g., up to about 80 degrees) to release fluid and at a velocity to facilitate movement of cuttings at a velocity flow on an uphole side of the hole cleaning joint. 
       FIG. 13  is a flow chart depicting a method  1300  of drilling a wellbore. The method involves  1350 —deploying a downhole tool from a rig via a drill string (see, e.g.,  FIG. 1 ). The method further involves  1352 —operatively connecting at least one hole cleaning joint to the drill string. The hole cleaning joint has at least one hole cleaning section with spiral grooves extending into an outer surface thereof. The spiral grooves have a width that decreases towards an uphole end thereof to define a tapered flow channel therethrough. 
     The method also involves  1354 —generating cuttings by advancing the downhole tool into the subterranean formation via the drill string, and  1356 —facilitating flow of the cuttings to the surface by passing a drilling fluid through the drill string and up an annulus between the drill string and a wall of the wellbore such that at least a portion of the cuttings pass through the tapered flow channel of the spiral grooves. The method may be performed in any order and repeated as desired. 
     While specific configurations of hole cleaning sections, joints and/or assemblies are provided, various combinations of hole cleaning sections, joints and/or assemblies may be provided alone or in combination with various ends, joints, rings, and/or other features along the drill string. Various geometries of the various components may also be provided. 
     It will be appreciated by those skilled in the art that the techniques disclosed herein can be implemented for automated/autonomous applications via software configured with algorithms to perform the desired functions. These aspects can be implemented by programming one or more suitable general-purpose computers having appropriate hardware. The programming may be accomplished through the use of one or more program storage devices readable by the processor(s) and encoding one or more programs of instructions executable by the computer for performing the operations described herein. The program storage device may take the form of, e.g., one or more floppy disks; a CD ROM or other optical disk; a read-only memory chip (ROM); and other forms of the kind well known in the art or subsequently developed. The program of instructions may be “object code,” i.e., in binary form that is executable more-or-less directly by the computer; in “source code” that requires compilation or interpretation before execution; or in some intermediate form such as partially compiled code. The precise forms of the program storage device and of the encoding of instructions are immaterial here. Aspects of the disclosure may also be configured to perform the described functions (via appropriate hardware/software) solely on site and/or remotely controlled via an extended communication (e.g., wireless, internet, satellite, etc.) network. 
     While the embodiments are described with reference to various implementations and exploitations, it will be understood that these embodiments are illustrative and that the scope of the inventive subject matter is not limited to them. Many variations, modifications, additions and improvements are possible. For example, one or more hole cleaning tools, wear pad, hole cleaning sections, pipe bodies, ends, connections, tubulars and/or other features as provided herein may be utilized along the drill string. In another example, a variety of geometries may be used for the wear pads, hole cleaning sections and grooves extending therein. 
     Plural instances may be provided for components, operations or structures described herein as a single instance. In general, structures and functionality presented as separate components in the exemplary configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements may fall within the scope of the inventive subject matter.