Patent Publication Number: US-10767422-B2

Title: Pipe joint having coupled adapter

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. non-provisional application Ser. No. 15/160,931 filed May 20, 2016, and entitled “Pipe Joint Having Coupled Adapter,” which is a continuation of U.S. non-provisional application Ser. No. 13/690,885 filed Nov. 30, 2012, and entitled “Pipe Joint Having Coupled Adapter,” now U.S. Pat. No. 9,366,094 issued on Jun. 14, 2016, all of which are incorporated herein by reference in their entirety for all purposes. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     BACKGROUND 
     Field of the Disclosure 
     This disclosure relates to connections between downhole tubulars, such as drill pipe tool joints or connections. More particularly, this disclosure relates to methods and apparatuses for strengthening the connections between wired drill pipe (WDP) joints. 
     Background of the Technology 
     In drilling by the rotary method, a drill bit is attached to the lower end of a drill stem composed of lengths of tubular drill pipe and other components that are joined together by connections with rotary shouldered threaded connections. In this disclosure, “drill stem” is intended to include other forms of downhole tubular strings such as drill strings and work strings. A rotary shouldered threaded connection may also be referred to as RSTC. 
     The drill stem may include threads that are engaged by right hand and/or left hand rotation. The threaded connections must sustain the weight of the drill stem, withstand the strain of repeated make-up and break-out, resist fatigue, resist additional make-up during drilling, provide a leak proof seal, and not loosen during normal operations. 
     The rotary drilling process subjects the drill stem to tremendous dynamic tensile stresses, dynamic bending stresses and dynamic rotational stresses that can result in premature drill stem failure due to fatigue. The accepted design of drill stem connections is to incorporate coarse tapered threads and metal to metal sealing shoulders. Proper design is a balance of strength between the internal and external thread connection. Some of the variables include outside diameter, inside diameters, thread pitch, thread form, sealing shoulder area, metal selection, grease friction factor and assembly torque. Those skilled in the art are aware of the interrelationships of these variables and the severity of the stresses placed on a drill stem. 
     The tool joints or pipe connections in the drill stem must have appropriate shoulder area, thread pitch, shear area and friction to transmit the required drilling torque. In use, all threads in the drill string must be assembled with a torque that exceeds the required drilling torque in order to handle tensile and bending loads without shoulder separation. Shoulder separation causes leaks and fretting wear. Relatively deeper wells require a greater amount of drilling torque to be applied to the drill string during drilling. In order to avoid uncontrolled downhole makeup of the drill string, the torque applied during makeup must be increased, thereby increasing the amount of stress on the RSTC connection. In response to this issue, double shouldered connections have been developed to better distribute stress generated from the makeup torque and apply it to the connection across a primary and a secondary shoulder of the RSTC. However, in the case of WDP, in order to transmit a signal along the length of the drill string, a groove is provided within the body of each tubular member of the drill string. This groove may extend through one of the shoulders of a double shouldered connection, forming a stress riser within the connection by reducing the surface area of the affected shoulder in the connection. 
     Accordingly, there remains a need in the art for an apparatus and methods for strengthening the connections between segments of drill pipe, particularly WDP. Such apparatuses and methods would be particularly well received if they could provide stronger connections in an efficient and relatively cost effective manner. 
     BRIEF SUMMARY OF THE DISCLOSURE 
     An embodiment of an adapter for a wired drill pipe joint comprises an annular adapter body having a first end and a second end, an annular recess extending partially into the first end of the adapter body, a communication element disposed at least partially within the annular recess, wherein the second end of the adapter body is configured to releasably couple to an end portion of a first wired drill pipe joint, wherein the annular adapter body comprises an arcuate key that is configured to restrict relative rotation of the adapter body with respect to the first wired drill pipe joint, wherein the annular adapter body and the communication element form a shoulder configured for engagement with a corresponding shoulder of a second wired drill pipe joint to form a rotary shouldered threaded connection between the first wired drill pipe joint and the second wired drill pipe joint. In some embodiments, the first wired drill pipe joint further comprises a slot, and wherein the arcuate key of the adapter body is configured to be inserted at least partially into the slot. In some embodiments, the adapter body comprises an outer surface extending from the first end of the adapter body, a mating surface extending from the second end of the adapter body, and a shoulder extending radially between the mating surface and the outer surface. In certain embodiments, the arcuate key of the adapter body extends over a portion of the annular shoulder. In certain embodiments, the annular adapter body comprises a plurality of the arcuate keys and wherein the arcuate keys are circumferentially spaced across the annular shoulder. In some embodiments, the arcuate key of the adapter body is configured to be inserted into an arcuate slot of the first wired drill pipe joint. In some embodiments, the adapter further comprises an annular latch coupled to the adapter body and configured to contact the first wired drill pipe joint when the adapter body is coupled to the first wired drill pipe joint and to resist decoupling of the adapter body from the first wired drill pipe joint. In certain embodiments, the latch comprises a canted coil spring. In certain embodiments, the latch is biased to expand radially outward with respect to a central axis of the latch. In some embodiments, the latch is disposed radially between the annular adapter body and the first wired drill pipe joint when the adapter body is coupled to the first wired drill pipe joint. 
     An embodiment of a method for forming a wired drill pipe joint comprises releasably coupling an annular adapter body to an end portion of a first wired drill pipe joint, disposing a communication element within an annular recess of the adapter body, and inserting an arcuate key of the adapter body into an arcuate slot of the first wired drill pipe joint to prevent relative rotation between the adapter body and the first wired drill pipe joint, wherein coupling the adapter body to an end portion of the first wired drill pipe joint forms an annular shoulder on an end portion of the first wired drill pipe joint that is configured to engage a corresponding annular shoulder of a second wired drill pipe joint for forming a rotary shouldered threaded connection between the first wired drill pipe joint and the second wired drill pipe joint. In some embodiments, the method further comprises inserting a plurality of the arcuate keys of the adapter body into a plurality of the arcuate slots of the first wired drill pipe joint. In some embodiments, the method further comprises decoupling the adapter body from the end portion of the first wired drill pipe joint. In certain embodiments, the method further comprises forming a joint between the first wired drill pipe joint and a second wired drill pipe joint, and providing a compressive stress against a side of the adapter body. In certain embodiments, the method further comprises communicating a signal between the first wired drill pipe joint and the second wired drill pipe joint. In some embodiments, the method further comprises disposing a latch in a recess positioned between the adapter body and the first wired drill pipe joint. In some embodiments, the method further comprises biasing the latch radially outwards into a recess of the first wired drill pipe joint to secure the adapter body to the first wired drill pipe joint. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a detailed description of the exemplary embodiments of the invention that are disclosed herein, reference will now be made to the accompanying drawings in which: 
         FIG. 1  is a schematic view of an embodiment of a drilling system in accordance with the principles described herein; 
         FIG. 2  is a perspective partial cross-sectional view of a pin end portion and a mating box end portion of a pair of tubulars used to form a drillstring as may be employed in the drilling system of  FIG. 1 ; 
         FIG. 3  is a cross-sectional view of a connection formed with the pin end portion and the box end portion of  FIG. 2 ; 
         FIG. 4  is a cross-sectional view of an embodiment of a strengthened shoulder of a RSTC as may be employed in the drilling system of  FIG. 1 ; 
         FIG. 5  is a cross-sectional view of another embodiment of a strengthened shoulder of a RSTC as may be employed in the drilling system of  FIG. 1 ; 
         FIGS. 6A and 6B  are cross-sectional views of an embodiment of a releasable shoulder of a RSTC as may be employed in the drilling system of  FIG. 1 ; 
         FIG. 6C  is a front view of an embodiment of a pin end of a wired drill pipe joint as may be employed in the drilling system of  FIG. 1 ; 
         FIG. 6D  is a front view of an embodiment of a releasable shoulder of a RSTC as may be employed in the drilling system of  FIG. 1 ; 
         FIG. 7  is a cross-sectional view of another embodiment of a releasable shoulder of a RSTC as may be employed in the drilling system of  FIG. 1 ; 
         FIG. 8  is a perspective partial cross-sectional view of a pin end portion and a mating box end portion of a pair of tubulars used to form a drillstring as may be employed in the drilling system of  FIG. 1 ; 
         FIG. 9  is a cross-sectional view of a connection formed with the pin end portion and the box end portion of  FIG. 8 ; and 
         FIG. 10  is a cross-sectional view of an embodiment of a strengthened shoulder of a RSTC as may be employed in the drilling system of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     The following discussion is directed to various exemplary embodiments. However, one skilled in the art will understand that the examples disclosed herein have broad application, and that the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to suggest that the scope of the disclosure, including the claims, is limited to that embodiment. The drawing figures are not necessarily to scale. Certain features and components herein may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in interest of clarity and conciseness. 
     In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .” Also, the term “couple” or “couples” is intended to mean either an indirect or direct connection. Thus, if a first device couples to a second device, that connection may be through a direct connection, or through an indirect connection via other devices, components, and connections. Further, “couple” or “couples” may refer to coupling via welding or via other means, such as releasable connections using a connector, pin, key or latch. In addition, as used herein, the terms “axial” and “axially” generally mean along or parallel to a given axis (e.g., given axis of a body or a port), while the terms “radial” and “radially” generally mean perpendicular to the given axis. For instance, an axial distance refers to a distance measured along or parallel to the given axis, and a radial distance means a distance measured perpendicular to the given axis. Still further, as used herein, the phrase “communication coupler” refers to a device or structure that communicates a signal across the respective ends of two adjacent tubular members, such as the threaded box/pin ends of adjacent pipe joints; and the phrase “wired drill pipe” or “WDP” refers to one or more tubular members, including drill pipe, drill collars, casing, tubing, subs, and other conduits, that are configured for use in a drill string and include a wired link. As used herein, the phrase “wired link” refers to a pathway that is at least partially wired along or through a WDP joint for conducting signals, and “communication link” refers to a plurality of communicatively-connected tubular members, such as interconnected WDP joints for conducting signals over a distance. 
     Referring now to  FIG. 1 , an embodiment of a drilling system  10  is schematically shown. In this embodiment, drilling system  10  includes a drilling rig  20  positioned over a borehole  11  penetrating a subsurface formation  12  and a drillstring  30  suspended in borehole  11  from a derrick  21  of rig  20 . Elongate drillstring  30  has a central or longitudinal axis  31 , a first or upper end  30   a , and a second or lower end  30   b  opposite end  30   a . In addition, drillstring  30  includes a drill bit  32  at lower end  30   b , a bottomhole assembly (BHA)  33  axially adjacent bit  32 , and a plurality of interconnected wired drill pipe (WDP) joints  34  between BHA  33  and upper end  30   a . BHA  33  and WDP joints  34  are coupled together end-to-end at tool joints or connections  70 . As will be discussed further herein, in this embodiment, connections  70  comprise double shouldered RSTCs. 
     In general, BHA  33  can include drill collars, drilling stabilizers, a mud motor, directional drilling equipment, a power generation turbine, as well as capabilities for measuring, processing, and storing information, and communicating with the surface (e.g., MWD/LWD tools, telemetry hardware, etc.). Examples of communication systems that may be included in BHA  33  are described in U.S. Pat. No. 5,339,037, incorporated herein in its entirety by this reference. 
     In this embodiment, drill bit  32  is rotated by rotation of drillstring  30  at the surface. In particular, drillstring  30  is rotated by a rotary table  22 , which engages a kelly  23  coupled to upper end  30   a . Kelly  23 , and hence drillstring  30 , is suspended from a hook  24  attached to a traveling block (not shown) with a rotary swivel  25  which permits rotation of drillstring  30  relative to hook  24 . Although drill bit  32  is rotated from the surface with drillstring  30  in this embodiment, in general, the drill bit (e.g., drill bit  32 ) can be rotated via a rotary table and/or a top drive, rotated by downhole mud motor disposed in the BHA (e.g., BHA  33 ), or by combinations thereof (e.g., rotated by both rotary table via the drillstring and the mud motor, rotated by a top drive and the mud motor, etc.). Thus, it should be appreciated that the various aspects disclosed herein are adapted for employment in each of these drilling configurations and are not limited to conventional rotary drilling operations. 
     In this embodiment, a transmitter in BHA  33  transmits communication signals through WDP joints  34  and drillstring  30  to a data analysis and communication system at the surface. As will be described in more detail below, each tubular in drillstring  30  (e.g., WDP joints  34 , etc.) includes a wired communication link that allows transmission of electronic communication signals along the tubular, and each connection  70  includes an inductive communication coupler that allows transmission of communication signals across the connection  70 , thereby enabling transmission of communication signals (e.g., electronic telemetry signals) between BHA  33  or other components in drillstring  30  and the communication system at the surface. Further, an adapter  100  is disposed at each connection  70  where it is coupled to an end of each WDP joint  34 . 
     Referring now to  FIGS. 2 and 3 , the tubulars forming drillstring  30  (e.g., WDP joints  34 , etc.) include an axial bore  35  that allows the flow of drilling fluid through string  30 , a tubular member or body  36  having a box end portion  50  at one end (e.g., the lower end), and a pin end portion  60  at the opposite end (e.g., the upper end). Box end portion  50  and pin end portion  60  physically interconnect adjacent tubulars end-to-end, thereby defining connections  70 . 
       FIGS. 2 and 3  illustrate one box end portion  50  and one mating pin end portion  60  for forming one connection  70 , it being understood that all the pin end portions, box end portions, and tool joints in drillstring  30  are configured similarly in this example. Box end portion  50  comprises an axial portion of WDP joint  34  extending between a secondary or radially inner shoulder  53  to a primary or radially outer shoulder  51  disposed at a terminal end  34   a  of WDP joint  34 . Box end portion  50  generally includes primary shoulder  51 , secondary shoulder  53  axially spaced apart from shoulder  51 , and internal threads  54  axially positioned between shoulders  51 ,  53 . Pin end portion  60  comprises an axial portion of WDP joint  34 , extending between a primary or radially outer shoulder  63  and a secondary or radially inner shoulder  102  disposed at a terminal end  34   b  of WDP joint  34 . Pin end portion  60  generally includes an annular adapter  100  that forms secondary shoulder  102 , primary shoulder  63  that is axially spaced from shoulder  102 , and external threads  64  that are axially positioned between shoulders  102 ,  63 . Since box end portion  50  and pin end portion  60  each include two planar shoulders  51 ,  53  and  102 ,  63 , respectively, ends  50  and  60  form a double shouldered RSTC upon being threaded together via mating threads  54 ,  64  to form connection  70 . When threading box end portion  50  into a pin end portion  60 , outer shoulders  51 ,  63  may axially abut and engage one another, and inner shoulders  53 ,  102  may axially abut and engage one another to provide structural support and to distribute stress across the connection. As shown in  FIG. 3 , upon forming connection  70 , box end portion  50  and pin end portion  60  axially overlap. as primary shoulders  51 ,  63  abut and secondary shoulders  53 ,  102  abut. 
     Referring still to  FIG. 3 , an inductive communication coupler  80  is used to communicate data signals across each connection  70  (i.e., communicated between mating box end portion  50  and pin end portion  60 ) in drillstring  30 . Although only one communication coupler  80  is shown in  FIG. 3 , each communication coupler  80  in drillstring  30  is configured similarly. Referring to  FIGS. 2 and 3 , communication coupler  80  is formed by physically engaging a first annular inductive coupler element  81  and a second annular inductive coupler element  82  axially opposed first inductive coupler element  81 . In this embodiment, first inductive coupler element  81  is seated in an annular recess  55  formed in inner shoulder  53  of box end portion  50 , and second inductive coupler element  82  is seated in an annular recess  65  formed in inner shoulder  102  of pin end portion  60  that comprises annular adaptor  100 . Recesses  55 ,  65 , formed in shoulders  53 ,  102 , respectively, decrease the surface area of each shoulder  53 ,  102 . Thus, given a compressive force applied axially against shoulders  53 ,  102 , the amount of stress imparted to each shoulder  53 ,  102  by the given compressive force is increased due to the smaller surface area afforded by the presence of recesses  55 ,  65 . In this embodiment, coupling elements  81 ,  82  are disposed in opposed recesses  55 ,  65 , of inner shoulders  53 ,  102 , respectively. However, in other embodiments, the inductive coupling elements (e.g., elements  81 ,  82 ) may be seated in opposed recesses formed in the outer shoulders (e.g., shoulders  51 ,  63 ), or a first pair of inductive coupling elements may be seated in opposed recesses formed in the outer shoulders and a second pair of inductive coupling elements can be seated in opposed recesses formed in the inner shoulders. 
     Referring still to  FIGS. 2 and 3 , coupler elements  81 ,  82 , disposed in the box end portion  50  and pin end portion  60 , respectively, of each tubular are interconnected by a cable  83  routed within the tubular body from the box end portion  50  to the pin end portion  60 . Cable  83  transmits signals between coupler elements  81 ,  82  of the tubular. Communication signals (e.g., telemetry communication signals) can be transmitted through cables  83  and couplers  80  from BHA  33  or other component in drillstring  30  to the communication system at the surface, or from the surface communication system to BHA  33  or other component in drillstring  30 . 
     Referring now to  FIG. 4 , an embodiment of a strengthened shoulder of a RSTC is shown. In this embodiment, annular adapter  100  is configured to couple to a terminal end of a tubular member, such as WDP joint  34 . Pin end portion  60  of WDP joint  34  comprises a first outer cylindrical surface  67   a , a second outer cylindrical surface  67   b , a third cylindrical outer surface  67   c , an inner cylindrical surface  69 , an outer or primary annular shoulder  63  extending radially inward from surface  67   a  to surface  67   b , a frustoconical threaded segment or portion  64  and a terminal end  66  that extends radially inward from surface  67   c  to inner surface  69 . Threaded portion  64  is configured to allow pin end portion  60  to couple with an associated box end portion of another WDP joint in the drill string. In this embodiment, annular inner or secondary shoulder  102  is formed on the pin end portion  60  of WDP joint  34  by coupling adapter  100  to terminal end  66  of pin end portion  60 . Annular adapter  100  has a central axis coaxial with axis  31 , a first end  100   a  and a second end  100   b . Annular secondary shoulder  102  of adapter  100  extends radially inward from an outer cylindrical surface  101   a  to an inner cylindrical surface  101   b  of adapter  100 , and includes an annular groove or recess  65  that extends axially into adapter  100  from shoulder  102 . In this embodiment, outer surface  101   a  has a radius substantially equal to surface  67   c  and inner surface  101   b  has a radius substantially equal to inner surface  69 . In the embodiment of  FIG. 4 , coupler element  82  may be disposed within recess  65  of adapter  100  to allow for the passing of electronic signals across the WDP joint  34  upon being made up with the box end portion of another WDP joint. 
     Referring still to  FIG. 4 , annular secondary shoulder  102  defines an annular face  104  having a surface area. During makeup procedures, as pin end portion  60  and box end portion of two adjacent WDP joints  34  are made up to form a connection  70 , a compressive force is applied to the face  104  of adapter  100  by a corresponding shoulder (e.g., shoulder  53  shown in  FIG. 2 ) on the box end portion of the other WDP joint. As discussed earlier, the surface area of face  104  that may contact an opposing annular shoulder of a box end portion is reduced by the presence of recess  65 , increasing the stress applied to the adapter  100  by a given compressive force generated during makeup. Thus, in order to maintain the same makeup torque used on tubular members that do not feature a recess  65  extending through an annular secondary shoulder, the strength of the material of the adapter  100  may be increased to allow the annular shoulder  102  to withstand a greater amount of applied compressive stress. In the embodiment of  FIG. 4 , adapter  100  comprises a material having high strength (e.g., compressive strength) and weldability characteristics with materials such as carbon steels, steel alloys, or other materials that may form drill pipe or other tubulars. For instance, adapter  100  comprises a material configured to have high strength, corrosion resistance and electrical conductivity. In this embodiment, the hardness of the material comprising adapter  100  has a harder Rockwell hardness than the material comprising WDP joint  34 . In an embodiment, the adapter  100  may comprise a steel alloy having a high nickel, chrome, cobalt, and/or copper content, such as Monel, Hastelloy, Inconel, Waspaloy, Rene alloys, and the like. In this configuration, while adapter  100  comprises a material having a high compressive strength, the material forming the rest of the WDP joint  34  may be carbon steel or other materials traditionally used to form drill pipe or other tubulars, allowing the WDP joint  34  to maintain its ductility and fatigue strength. An alloy containing a high nickel content may be chosen to augment the strength of the adapter  100 . In an embodiment, adapter  100  may also comprise a material suitable for high strength and/or to reduce or eliminate corrosion. An alloy containing a high copper content may be chosen to augment the electrical conductivity of adapter  100 . In another embodiment, adapter  100  may comprise a high nickel content steel alloy coated in a higher copper content material in order to provide for both high strength and electrical conductivity of adapter  100 . 
     Referring still to  FIG. 4 , first end  100   a  of adapter  100  is configured to couple to WDP joint  34  at terminal end  66  of the joint  34 . The adapter  100  may be coupled at first end  100   a  to end  66  of WDP joint  34  using a means configured to allow the adapter  100  to resist torsional, compressive and other loads applied to adapter  100 . For instance, adapter  100  may be welded at first end  100   a  to end  66  of WDP joint  34  using an electron beam welding procedure where the kinetic energy of a beam of electrons is used to fuse the adapter  100  and WDP joint  34  together at ends  100   a  and  66 . In another embodiment, adapter  100  may be friction welded to WDP joint  34  at ends  100   a  and  66 , respectively. For instance, in this procedure annular adapter  100  may be rotated about axis  31  as first end  100   a  of adapter  100  abuts and physically engages end  66  of WDP joint  34 , causing adapter  100  and WDP joint  34  to fuse together at ends  100   a ,  66  due to the friction generated by the sliding engagement between adapter  100  and WDP joint  34 . 
     Referring to  FIG. 5 , another embodiment of a strengthened shoulder of a RSTC is shown to include an adapter  200  configured to be coupled to a terminal end of a tubular member, such as WDP joint  34 . A pin end portion  260  of WDP joint  34  comprises outer surfaces  67   a ,  67   b ,  67   c , inner surface  69 , threaded portion  64  and a mating cylindrical surface  264 . In this embodiment, the radius of surface  264  is larger than the radius of inner surface  69  but smaller than the radius of outer surface  67   c . An upper mating shoulder  262  is formed at a terminal end  261  of WDP joint  34  and radially extends inward from cylindrical surface  67   c  to surface  264 . Cylindrical surface  264  extends axially into WDP joint  34  from terminal end  261 . A lower mating shoulder  266  radially extends inward from cylindrical surfaces  264  to inner cylindrical surface  69 . 
     Secondary shoulder  102  may be formed on pin end portion  260  of WDP joint  34  by coupling adapter  200  to WDP joint  34 . In this embodiment, adapter  200  is configured to physically engage mating shoulders  262 ,  266  and cylindrical surface  264  of WDP joint  34 . Adapter  200  has a central axis coaxial with axis  31  and comprises a first end  200   a , a second end  200   b , an outer cylindrical surface  208 , an inner cylindrical surface  209  and a mating cylindrical surface  204 . In this embodiment, the radius of surface  204  is larger than the radius of inner surface  209  but smaller than the radius of surface  208 . A lower annular shoulder  206  is disposed at end  200   a  and extends radially outward from inner surface  209  to surface  204 . Surface  204  extends axially from first end  200   a  toward second end  200   b . An upper annular shoulder  202  extends radially outward from surface  264  to outer surface  208 . As shown, shoulders  206 ,  202  of adapter  200  are configured to physically engage corresponding shoulders  266 ,  262  of WDP joint  34 . Also, cylindrical surface  204  of adapter  200  is configured to engage corresponding surface  264  of WDP joint  34 . 
     Adapter  200  may comprise the same materials as discussed with respect to annular adapter  100  (e.g., high nickel content and/or high copper content alloy steel) to provide for greater strength compared to the materials comprising WPD joint  34 . Adapter  200  comprises a material having a harder Rockwell hardness rating than the material comprising WDP joint  34 . In an embodiment, adapter  200  and WDP joint  34  may be coupled at their respective mating surface using a tungsten inert gas (TIG) welding procedure using a filler rod comprising a material configured to allow the high nickel and/or high copper content of the adapter  200  to couple with the WDP joint  34 , which may comprise carbon steel or other materials. In an embodiment, radial surface  204  of adapter  200  may be press fit against WDP joint  34  at radial surface  264  prior to welding adapter  200  to the WDP joint  34 . In this embodiment, press fitting adapter  200  against WDP joint  34  may ensure proper alignment between the two members prior to welding. 
     Referring to  FIGS. 6A and 6B , another embodiment of a strengthened shoulder of a RSTC is shown. For clarity, an enlarged version of adapter  300  is shown by  FIG. 6A . In this embodiment, an adapter  300  is configured to be coupled to a terminal end of a tubular member, such as WDP joint  34 . Adapter  300  is configured to be releasably electrically coupled to WDP joint  34  via a connector  85 . Adapter  300  may comprise the same materials as discussed with respect to annular adapters  100  and  200  (e.g., high nickel content and/or high copper content alloy steel) to provide for greater strength compared to the materials comprising WPD joint  34 . In the embodiment of  FIGS. 6A and 6B , adapter  300  may comprise materials having a harder Rockwell hardness rating than the materials comprising WDP joint  34 . 
     As shown in  FIG. 6B , cable  83  extends axially through WDP joint  34  to connector  85  that is disposed in a cavity  88  of the WDP joint  34 . Connector  85  comprises a boot or socket  89  that is configured to allow for the conduction of electricity through the connector  85 . Coupled to coupler element  82  is an elongate or generally cylindrical pin  86  ( FIG. 6A ) having one or more protrusions  87  that extend radially from pin  86 . Pin  86  is an electrical conductor and may be inserted partially into connector  85  such that an electric signal may flow from cable  83 , through connector  85  and pin  86  and into coupler element  82 , or vice-a-versa (e.g., from coupler element  82  to cable  83 ). Pin  86  is an electrical conductor and may be inserted partially into connector  85  such that an electric signal may flow from cable  83 , through connector  85  and pin  86  and into coupler element  82 , or vice-a-versa (e.g., from coupler element  82  to cable  83 ). Protrusions  87  are configured to radially extend into socket  89  as pin  86  is inserted into connector  85 . The physical engagement between protrusions  87  and socket  89  provide an axial resistance to the attached coupler element  82  and adapter  300  from becoming uncoupled from WDP joint  34 . For instance, connector  85  may provide an axial force on protrusions  87  in the direction of WDP joint  34  in response to an opposed axial force on adapter  300  or coupler element  82  in the axial direction away from WDP joint  34 . However, because socket  89  is formed from an elastomeric or deformable material, a large enough axial force applied to  300  will cause protrusions  87  to temporarily deform the material of socket  89 , allowing adapter  300  to be uncoupled from pin end portion  360  of WDP joint  34 . An annular partition  313  may extend through recess  65  to retain coupler element  82  within recess  65 . One or more openings may be formed within annular partition  313  to allow pin  86  to extend axially therethrough. 
     In this embodiment, a pin end portion  360  of WDP joint  34  comprises outer surfaces  67   a ,  67   b ,  67   c , inner surface  69 , threaded portion  64  and a mating cylindrical surface  464 . The radius of surface  364  is larger than the radius of inner surface  69  but smaller than the radius of outer surface  67   c . An upper mating shoulder  362  is formed at a terminal end  361  of WDP joint  34  and radially extends inward from cylindrical surface  67   c  to surface  364 . Cylindrical surface  364  extends axially into WDP joint  34  from terminal end  361 . A lower mating shoulder  366  radially extends inward from cylindrical surfaces  364  to inner cylindrical surface  69 . 
     Secondary annular shoulder  102  may be formed on pin end portion  360  of WDP joint  34  by coupling adapter  300  to WDP joint  34 . In this embodiment, adapter  300  is configured to physically engage mating shoulders  362 ,  366  and cylindrical surface  364  of WDP joint  34 . Adapter  300  has a central axis that is coaxial with axis  31  and comprises a first end  300   a , a second end  300   b , an outer cylindrical surface  308 , an inner cylindrical surface  309  and a mating cylindrical surface  304  ( FIG. 6A ). In this embodiment, the radius of surface  304  is larger than the radius of inner surface  309  but smaller than the radius of surface  308 . A lower annular shoulder  306  is disposed at end  300   a  and extends radially outward from inner surface  309  to surface  304 . Surface  304  extends axially from first end  300   a  toward second end  300   b . An upper annular shoulder  302  ( FIG. 6A ) extends radially outward from surface  364  to outer surface  308 . In this embodiment, shoulders  306 ,  302  of adapter  300  are configured to physically engage corresponding shoulders  366 ,  362  of WDP joint  34 . Also, cylindrical surface  304  of adapter  300  is configured to engage corresponding surface  364  of WDP joint  34 . 
     Referring to  FIGS. 6A-6D , adapter  300  also comprises one or more arcuate anti-rotation keys  310  ( FIGS. 6A, 6C ) that are configured to physically engage one or more recesses in WDP joint  34  in order to restrict relative rotation of adapter  300  with respect to WDP joint  34 . As shown in  FIG. 6C , keys  310  are arcuate shaped members having a radius and a circumferential length that extends only over a portion of the circumference of shoulder  302 . Thus, a plurality of keys  310  may be disposed at different circumferential positions along shoulder  302 . Keys  310  are defined by outer cylindrical surface  308 , mating cylindrical surface  304 , and two radial edges,  311   a  and  311   b , that radially extend between cylindrical surfaces  308  and  304 . Although in this embodiment four arcuate keys  310  are shown, in other embodiments a different number of keys  310  may be used. 
     Keys  310  are configured to be inserted into one or more corresponding arcuate slots  312  that are disposed on upper mating surface  362  of pin end portion  360 . Each arcuate shaped slot  312  is defined by outer surface  67   c , cylindrical surface  364  and edges  314   a ,  314   b , that radially extend between cylindrical surfaces  67   c ,  364 . Each slot  312  extends axially into WDP joint  34  from upper mating shoulder  362 , defining an inner vertical surface  314 . Arcuate slots  312  each extend over a portion of the circumference of mating shoulder  362 , and thus a plurality of slots  312  may be disposed at different circumferential positions along the circumference of shoulder  362 . As each arcuate key  310  is inserted into a corresponding arcuate slot  312 , edges  311   a ,  311   b , of each key  310  slidably engages edges  314   a ,  314   b , of each arcuate slot  312 . In this embodiment, keys  310  are configured to prevent the relative rotation of adapter  300  with respect to WDP joint  34  as pin end portion  60  of WDP joint  34  is threadedly coupled with a box end portion of an adjacent WDP joint. Thus, by restricting the relative rotation of adapter  300  with respect to WDP joint  34 , the electrical connection between cable  83  and coupler element  82  may be protected from severing due to relative rotation by adapter  300 . In this embodiment, adapter  300  is secured to WDP joint  34  with keys  310  and connector  85 , and thus is not required to be permanently coupled (e.g., welded) to WDP joint  34  in order to form pin end portion  60 . 
     In an embodiment, axial movement of annular adapter  300  is prevented by the physical engagement between connector  85  and the protrusions  87  of pin  86 . Further, adapter  300  is restricted from relative rotational movement with respect to WDP joint  34  by one or more anti-rotation keys  310  disposed within one or more slots  312  of WDP joint  34 . However, with enough axial force applied to either coupler element  82  or adapter  300 , pin  86  may be displaced from connector  85  without damaging or altering any of the components (adapter  300 , connector  85 , WDP joint  34 , etc.). Thus, adapter  300  and coupler element  82  may be releasably coupled to WDP joint  34  via connector  85 . 
     Referring to  FIG. 7 , another embodiment of a removable strengthened shoulder of a RSTC is shown. In this embodiment, an adapter  400  is configured to be releasably coupled to a terminal end of a tubular member, such as WDP joint  34  via a latch  470 . In an embodiment, latch  470  is configured to resist decoupling of adapter  400  from the WDP joint  34 . A pin end portion  460  of WDP joint  34  comprises outer surfaces  67   a ,  67   b ,  67   c , inner surface  69 , threaded portion  64  and a mating cylindrical surface  464 . In this embodiment, the radius of surface  464  is larger than the radius of inner surface  69  but smaller than the radius of outer surface  67   c . An upper mating shoulder  462  is formed at a terminal end  461  of WDP joint  34  and radially extends inward from cylindrical surface  67   c  to surface  464 . Cylindrical surface  464  extends axially into WDP joint  34  from terminal end  461 . A lower mating shoulder  466  radially extends inward from cylindrical surfaces  464  to inner cylindrical surface  69 . 
     Secondary annular shoulder  102  may be formed on pin end portion  260  of WDP joint  34  by coupling adapter  400  to WDP joint  34 . In this embodiment, adapter  400  is configured to physically engage mating shoulders  462 ,  466  and cylindrical surface  464  of WDP joint  34 . Adapter  400  has a central axis coaxial with axis  31  and comprises a first end  400   a , a second end  400   b , an outer cylindrical surface  408 , an inner cylindrical surface  409  and a mating cylindrical surface  404 . In this embodiment, the radius of surface  404  is larger than the radius of inner surface  409  but smaller than the radius of surface  408 . A lower annular shoulder  406  is disposed at end  400   a  and extends radially outward from inner surface  409  to surface  404 . Surface  404  extends axially from first end  400   a  toward second end  400   b . An upper annular shoulder  402  extends radially outward from surface  404  to outer surface  408 . In this embodiment, shoulder  406  of adapter  400  is configured to physically engage corresponding shoulder  466  of WDP joint  34 . A slight gap exists between surfaces  464 ,  404 , and  462 ,  402 , respectively. Alternatively, in another embodiment shoulders  402  and  462  physically engage while a slight gap exists between surfaces  406 ,  466 , and  404 ,  464 , respectively. In another embodiment, shoulders  404  and  464  physically engage while a slight gap exists between shoulders  402 ,  462  and  406 ,  466 , respectively. Adapter  400  may comprise the same materials as discussed with respect to annular adapters  100 ,  200 ,  300  (e.g., high nickel content and/or high copper content alloy steel) to provide for greater strength compared to the materials comprising WPD joint  34 . In this embodiment, adapter  400  comprises a material having a harder Rockwell hardness rating than the material comprising WDP joint  34 . 
     In this embodiment, pin end portion  460  and adapter  400  further comprise an annular latch  470  that is configured to releasably secure annular adapter  400  to WDP joint  34 . Latch  470  has a central axis coaxial with axis  31  and is disposed within an annular cavity  472  that is defined by an upper recess  473  that extends radially into cylindrical surface  464  and a lower recess  474  that extends radially into cylindrical surface  404 . Latch  470  is an annular member that extends entirely about axis  31 . In an embodiment, latch  470  comprises rubber or other elastomeric, pliable or deformable material. In another embodiment, latch  470  comprises a spring. In this embodiment, latch  470  comprises a canted coiled spring connector, such as the Bal Latch connectors provided by Bal Seal Engineering, Inc., of 19650 Pauling, Foothill Ranch, Calif. 92610. 
     Latch  470  is biased to expand radially outward away from axis  31  and toward upper recess  473  of WDP joint  34 . Because latch  470  is disposed within both upper recess  473  and lower recess  474 , an axial force applied to annular adapter  400  in the direction away from WDP joint  34  will be resisted by physical engagement between latch  470  and recesses  473  and  474 . However, a large enough axial force on adapter  400  may deform latch  470  such that latch  470  is displaced into either upper recess  473  or lower recess  474 , which allows adapter  400  to be removed or disengaged from WDP joint  34  via an axial force applied to adapter  400 . In this embodiment, latch  470  is useful for retaining adapter  400  on WDP joint  34  during transportation to a drilling system (e.g., drilling system  10 ) or storage thereat prior to being introduced into a borehole (e.g., borehole  11 ). Once pin end portion  460  of WDP joint  34  comprising latch  470  has been threadedly coupled to a corresponding box end portion of another WDP joint, the compressive stress placed on shoulder  102  due to the applied makeup torque will retain adapter  400  into place. Further, in this embodiment, anti-rotation keys, such as anti-rotation keys  310  discussed with reference to  FIGS. 6A, 6B , may be used to restrict adapter  400  from rotating relative to WDP joint  34 . A latch, such as latch  470 , may also be used with adapter  300 , so as to restrict axial movement of adapter  300  prior to coupling with another WDP joint. An electrical connection similar to the one described with respect to adapter  300  may also be implemented in a similar manner. 
     Referring now to  FIGS. 8 and 9 , an alternative embodiment of a strengthened annular shoulder is shown. In this embodiment, the tubulars forming drillstring  30  (e.g., WDP joints  34 , etc.) include a box end portion  550  and a mating pin end portion  560 , it being understood that all the pin end portions, box end portions, tubular body  36  and connections in drillstring  30  are configured similarly in this example. Pin end portion  560  comprises an axial portion of WDP joint  34  extending between primary or radially outer shoulder  63  and a secondary or radially inner shoulder  562  disposed at terminal end  34   b  of WDP joint  34 . Pin end portion  560  generally includes primary shoulder  63 , secondary shoulder  562  axially displaced from shoulder  63 , and threads  64 . Box end portion  550  comprises an axial portion of WDP joint  34  extending between a secondary or radially inner shoulder  502  and primary or radially outer shoulder  51  disposed at terminal end  34   a  of WDP joint  34 . Box end portion  550  includes primary outer shoulder  51  and a strengthened annular adapter  500  that forms a secondary or inner annular shoulder  502 . Since box end portion  550  and pin end portion  560  each include two planar shoulders  51 ,  502  and  63 ,  562 , respectively, ends  550 ,  560  form a double shouldered RSTC upon being threaded together via mating threads  54 ,  64  to form connection  570 . When threading box end portion  550  into a pin end portion  560 , outer shoulders  51 ,  63  may axially abut and engage one another, and inner shoulders  502 ,  562  may axially abut and engage one another to provide structural support and to distribute stress across the connection. First inductive coupler element  81  is seated in an annular recess  55  formed in inner shoulder  502  of annular adapter  500 , and second inductive coupler element  81  is seated in an annular recess  65  formed in inner shoulder  562  of pin end portion  560 . As shown in  FIG. 9 , upon forming a connection  570 , box end portion  550  and pin end portion  560  axially overlap. as primary shoulders  51 ,  63  abut and secondary shoulders  502 ,  562  abut. 
     Referring now to  FIG. 10 , an embodiment of a strengthened shoulder of a box end portion of a RSTC is shown. In this embodiment, annular adapter  500  is configured to be coupled to a box end portion of a tubular member, such as WDP joint  34 . Box end portion  550  of a WDP joint  34  comprises a first inner cylindrical surface  52   a , a second inner cylindrical surface  52   b , a third cylindrical inner surface  52   c , an outer cylindrical surface  59 , an inner or primary annular shoulder  553  extending radially from surface  52   a  to surface  52   b , a frustoconical threaded segment or portion  54  and outer radial shoulder  51  that extends radially from cylindrical surface  52   c  to outer surface  59 . In this embodiment, inner annular shoulder  502  is formed on the box end portion  550  of a WDP joint by coupling adapter  500  to shoulder  553  of box end portion  550 . Annular adapter  500  has a central axis coaxial with axis  31 , a first end  500   a  and a second end  500   b . Annular secondary shoulder  502  of adapter  500  extends radially from an inner cylindrical surface  501   a  to an outer cylindrical surface  501   b , and includes annular groove or recess  55  that extends axially into adapter  500  from terminal end  500   b . In this embodiment, inner surface  501   a  has a radius substantially equal to the radius of surface  52   a  and outer surface  501   b  has a radius substantially equal to the radius of surface  52   b . In the embodiment of  FIG. 9 , coupler element  81  is disposed within recess  55  of adapter  500  to allow for the passing of electronic signals across the WDP joint  34  upon being made up with the pin end portion  560  of an adjacent WDP joint. 
     Annular secondary shoulder  502  defines an annular face  504  having a surface area. During makeup procedures, as box end portion  560  and pin end portion  550  of two adjacent WDP joints  34  are made up to form joint  570 , a compressive force is applied to the face  504  of adapter  500  by a corresponding shoulder (e.g., shoulder  562  shown in  FIG. 8 ) on the pin end portion of the other WDP joint. In the embodiment of  FIG. 9 , adapter  500  comprises a material configured to have high strength (e.g., compressive strength) and weldability characteristics with materials such as carbon steels, steel alloys, or other materials that may form drill pipe or other tubulars. In this embodiment, the hardness of the material comprising adapter  500  has a harder Rockwell hardness than the material comprising WDP joint  34 . Adapter  500  comprises a steel alloy having a high nickel, chrome, cobalt, and/or copper content, such as Monel, Hastelloy, Inconel, Waspaloy, Rene alloys, and the like. An alloy containing a high nickel content may be chosen to augment the strength of the adapter  500 . An alloy containing a high copper content may be chosen to augment the electrical conductivity of adapter  500 . In another embodiment, adapter  500  may comprise a high nickel content steel alloy coated in a higher copper content material in order to provide for both high strength and electrical conductivity of adapter  500 . 
     Referring still to  FIG. 10 , first end  500   a  of adapter  500  is configured to couple to WDP joint  34  at shoulder  553  of the joint  34 . Adapter  500  is coupled at first end  500   a  to shoulder  553  of WDP joint  34  using a means configured to allow the adapter  500  to resist torsional, compressive and other loads applied to adapter  500 . For instance, adapter  500  is welded at first end  500   a  to shoulder  553  of WDP joint  34  using an electron beam welding procedure where the kinetic energy of a beam of electrons is used to fuse the adapter  500  and WDP joint  34  together at end  500   a  and shoulder  553 . In another embodiment, adapter  500  may be friction welded to WDP joint  34  at end  500   a  and shoulder  553 , respectively. For instance, in this procedure annular adapter  500  is rotated about axis  31  as first end  500   a  of adapter  500  abuts and physically engages shoulder  553  of WDP joint  34 , causing adapter  500  and WDP joint  34  to fuse together at end  500   a  and shoulder  553  due to the friction generated by the sliding engagement between adapter  500  and WDP joint  34 . In still further embodiments, adapter  500  may be coupled to box end portion of a WDP joint using a TIG welding procedure, or adapter  500  may be releasably coupled to WDP joint  34  using a removable connector, as described with respect to the embodiment shown in  FIGS. 6A-6C . 
     The embodiments described herein may be used to strengthen a RSTC connection with respect to the stresses placed on the RSTC connection during makeup. Such embodiments offer the potential for improved durability of the RSTC connections with respect to conventional wired drilling pipes that are employed without strengthened adapters. Further, the embodiments described herein offer the potential of increasing the amount of makeup torque that can be applied during the coupling of WDP joints or tubulars. For example, a WDP comprising an adapter formed from relatively higher strength material may withstand higher compressive loads resulting from makeup, than a WDP featuring an adapter formed from standard drill pipe material. Moreover, because only the adapter (e.g., adapter  100 ,  200 ,  300 ,  400  and  500 ) comprises the relatively stronger materials (e.g., high nickel and/or copper steel alloys), the benefits of ductility and fatigue resistance offered by traditional drilling pipe materials (e.g., carbon steel) may still be relied upon as a substantial amount of material comprising the WDP would remain as traditional drilling pipe materials. 
     While embodiments have been shown and described, modifications thereof can be made by one skilled in the art without departing from the scope or teachings herein. The embodiments described herein are exemplary only and are not limiting. Many variations and modifications of the systems, apparatus, and processes described herein are possible and are within the scope of the invention. Accordingly, the scope of protection is not limited to the embodiments described herein, but is only limited by the claims that follow, the scope of which shall include all equivalents of the subject matter of the claims. Unless expressly stated otherwise, the steps in a method claim may be performed in any order. The recitation of identifiers such as (a), (b), (c) or (1), (2), (3) before steps in a method claim are not intended to and do not specify a particular order to the steps, but rather are used to simplify subsequent reference to such steps.