Abstract:
The present invention generally relates to a method and apparatus for protecting tubular connections. In one aspect, an expandable tubular connection for use in a wellbore is provided. The tubular connection includes a tubular pin member. The tubular connection also includes a tubular box member having an end portion, wherein the tubular pin member is matable with the tubular box member to form the tubular connection. Additionally, the tubular connection includes a sleeve member disposed on the tubular pin member, wherein the sleeve member is configured to substantially protect the end portion of the tubular box member as the tubular connection is lowered into the wellbore. In yet a further aspect, a method for utilizing a tubular connection in a wellbore is provided.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims benefit of U.S. provisional patent application Ser. No. 60/747,909 filed May 22, 2006, which is herein incorporated by reference in entirely. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   Embodiments of the present invention generally relate to wellbore completion, and more particularly, to tubular connections. 
   2. Description of the Related Art 
   In order to access hydrocarbons in subsurface formations, it is typically necessary to drill a borehole into the earth. The process of drilling a borehole and of subsequently completing the borehole in order to form a wellbore requires the use of various tubular strings. These tubulars are run downhole where the mechanical and seal integrity of the jointed connections are critically important. 
   Generally, male to female threaded connections connect multiple tubular members end-to-end. The male end is referred to as a pin and the female end as a box. The tubulars are connected, or “made-up,” by transmitting torque against one of the tubulars while the other tubular is typically held stationary. Transmitting torque in a single direction corresponding with connection make-up tightens the threaded joint in order to establish the seal integrity and lock in the applied torque. 
   When running tubulars, there is sometimes a requirement to run jointed tubulars that will later be expanded by various types of expansion mechanisms. The basic type of expander tool employs a cone-shaped body, which is run into a wellbore at the bottom of the casing that is to be expanded. The expander tool is then forced upward in the wellbore by both pulling on the working string from the surface and applying pressure below the cone. Pulling the expanded conical tool has the effect of expanding a portion of a tubular into sealed engagement with a surrounding formation wall, thereby sealing off the annular region therebetween. More recently, rotary expander tools have been developed. Rotary expander tools employ one or more rows of compliant rollers that are urged radially outwardly from a body of the expander tool in order to engage and to expand the surrounding tubular. The expander tool is rotated downhole so that the actuated rollers can act against the inner surface of the tubular to be expanded in order to expand the tubular body circumferentially. Radial expander tools are described in U.S. Pat. No. 6,457,532, issued to Simpson et al., which is incorporated herein by reference in its entirety. 
   One problem that may occur during a completion operation is that the tubular string may get scratched when the tubular string contacts a portion of the wellbore when the tubular string is lowered into the wellbore. Normally, a scratch on a tubular does not affect the integrity of the tubular. However, a scratch on a tubular connection between the tubulars may be problematic. For instance, if the scratch occurs on the box portion of the tubular connection near the thin face of the box, then the box portion may split apart when the tubular connection is expanded. As such, the structural integrity of the entire tubular connection may be compromised. 
   Therefore, a need exists for an apparatus and a method to protect expandable tubular connections, thereby maintaining the mechanical and/or sealing integrity of the connection. 
   SUMMARY OF THE INVENTION 
   The present invention generally relates to a method and apparatus for protecting tubular connections. In one aspect, an expandable tubular connection for use in a wellbore is provided. The tubular connection includes a tubular pin member. The tubular connection also includes a tubular box member having an end portion, wherein the tubular pin member is matable with the tubular box member to form the tubular connection. Additionally, the tubular connection includes a sleeve member disposed on the tubular pin member, wherein the sleeve member is configured to substantially protect the end portion of the tubular box member as the tubular connection is lowered into the wellbore. 
   In a further aspect, an expandable tubular connection for use in a wellbore is provided. The connection includes a tubular box member having an end portion. The connection further includes a tubular pin member having an outer diameter greater than an outer diameter of the tubular box member, wherein a portion of the tubular pin member is configured to substantially shield the end portion of the tubular box member from contact with the wellbore. 
   In yet a further aspect, a method for utilizing a tubular connection in a wellbore is provided. The method includes the step of positioning a sleeve member on the tubular pin member. The method also includes the step of connecting a tubular pin member with a tubular box member to provide the tubular connection. Further, the method includes the step of substantially blocking an end portion of the tubular box member from contact with the wellbore by utilizing the sleeve member as the tubular connection is lowered into the wellbore. Additionally, the method includes the step of expanding the tubular connection. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. 
       FIG. 1  illustrates a threaded connection of the present invention within a wellbore. 
       FIG. 2  illustrates the threaded connection with a sleeve member in accordance with the present invention. 
       FIG. 3  illustrates the threaded connection with a sleeve member in accordance with the present invention. 
       FIG. 4  illustrates the threaded connection with a sleeve member in accordance with the present invention. 
       FIG. 5  illustrates the threaded connection in accordance with the present invention. 
       FIG. 6  illustrates the threaded connection in accordance with the present invention. 
       FIG. 7  illustrates the threaded connection in accordance with the present invention. 
       FIG. 8  illustrates the threaded connection in accordance with the present invention. 
       FIG. 9  illustrates the threaded connection in accordance with the present invention. 
       FIG. 10  illustrates a cross-section of the threaded connection in accordance with the present invention. 
   

   DETAILED DESCRIPTION 
     FIG. 1  illustrates an embodiment of the present invention in use within a wellbore  10 . Visible in  FIG. 1  is a representative rig  15 , a ground surface  20 , a formation  30 , a drill string  25  (or running string), a first tubular  100 , a second tubular  200 , a representative expander tool  40  comprising a body  55  and an expansion member  45  (or roller), a bore  65 , and a connection  150  (or joint), between the first tubular  100  and the second tubular  200 . Although the representative expander tool  40  is illustrated in  FIG. 1  as a rotary expander tool, it should be understood that the representative expander tool could be a cone member, a swage member, or any other expander member known in the art. 
   In operation, the first tubular  100  and the second tubular  200  are mated together at the surface  20  according to normal stab-in and threading procedures. The stab-in procedures can be performed with tubulars arranged in a pin up and a box down configuration or in a pin down and a box up configuration. After run-in, the tubulars can be expanded from within by any method known to those skilled in the art. The expansion process can be run in any axial and/or rotational direction within the tubulars  100 ,  200 . For illustrative purposes, a running tool with an expander tool  40  attached thereto is run through the bore  65  of the tubulars. At a desired location, the tool  40  expands the tubulars. When the expander tool  40  reaches the connection  150  between the first tubular  100  and the second tubular  200 , an internal wall of the pin portion of the first tubular  100  expands into an internal wall of the box portion of the second tubular  200 . The connection  150  between the tubulars  100 ,  200  is capable of being expanded without losing its mechanical or sealing integrity. 
     FIG. 2  illustrates the threaded connection  150  in accordance with the present invention. The connection  150  includes a pin member  110  formed at a threaded section of the first tubular  100  and a box member  210  formed at a threaded section of the second tubular  200 . As illustrated, the pin member  110  has an outer diameter greater than or equal to an outer diameter of the box member  210 . In one embodiment, the threaded sections of the pin member  110  and the box member  210  are tapered. The pin member  110  includes helical threads  115  extending along its length. The box member  210  includes helical threads  215  that are shaped and sized to mate with the helical threads  115  during the make-up of the threaded connection  150 . The threaded sections of the pin member  110  and the box member  210  form the connection  150  of a predetermined integrity when the pin member  110  is mated with the box member  210 . Additionally, depending upon wellbore characteristics, the threads may be coated with Teflon™, an inert sealant, or other material known to those in the art for sealing purposes. The threads may be machined on plain end tubulars, tubulars with both ends formed, tubulars with one plain end and one end formed, or other connection types as typically used in the oil and gas industry. One of ordinary skill in the art can appreciate that embodiments of the present invention are not limited to only certain kinds of tubular ends or thread types. 
   As shown in  FIG. 2 , a sleeve  175  is disposed around the pin member  110  to increase the outer diameter of the pin member  110 . Generally, the sleeve  175  is used to protect a portion of the connection  150  adjacent the sleeve  175 , namely the box member  210 . More specifically, the sleeve  175  is positioned on the pin member  110  proximate an end portion  205  of the box member  210  to substantially prevent the surrounding wellbore from contacting and/or scratching the end portion  205  of the box member  210 . Typically, the end portion  205  is the thinnest part of the connection  150  and a scratch on the end portion  205  may cause the box member  210  to split apart upon expansion of the connection  150 . Therefore, the sleeve  175  increases the outer diameter of the pin member  110  without adding substantial thickness to the connection  150 . The sleeve  175  is configured to substantially block or shield the end portion  205  from contact with the surrounding wellbore as the tubular string is lowered into the wellbore. In the embodiment illustrated, the sleeve  175  is disposed on a non-threaded portion of the tubular  100  and therefore does not add any thickness to the threaded portion of the pin member  110  or box member  210 , which upon forming the connection  150  may be the thickest portion of the connection  150 . As a result, the threaded portion of the connection  150  is protected and the connection  150  may be expanded without concern about additional thickness on the threaded portion of the connection  150 . 
   As illustrated, the sleeve  175  includes a tab  180  proximate an end thereof that fits between a shoulder of the pin member  110  and an end of the box member  210 . The tab  180  is configured to hold the sleeve  175  in the position illustrated in  FIG. 2 . It should be understood, however, that the sleeve  175  may be secured to the connection  150  by any means known in the art, such as via an epoxy, an adhesive, a weld, or shrink fit, without departing from principles of the present invention. 
   The sleeve  175  may be made from any type of material that is durable yet capable of expanding, such as metal, elastomeric, plastic, or a polymeric. In one embodiment, the sleeve  175  may be made from a solid material as illustrated in  FIG. 2 . In another embodiment, the sleeve  175  may have slots, holes, or any other geometric shapes (not shown) formed therein. The geometric shape formed in the sleeve  175  may be used to enhance the capability of the sleeve  175  to expand radially outward and/or the geometric shape may be used to allow fluid flow past the sleeve  175 . In a further embodiment, a plastic and/or an elastomer layer may be disposed on top of the sleeve  175  to further offset the connection  150  from the surrounding wellbore. 
     FIG. 3  illustrates the threaded connection  150  with a sleeve member  225  in accordance with the present invention. For convenience, the components in  FIG. 3  that are similar to the components in  FIGS. 1 and 2  will be labeled with the same number indicator. As shown, the sleeve  225  is disposed around the pin member  110  and as a result the pin member  110  has an outer diameter greater than an outer diameter of the box member  210  without adding substantial thickness to the connection  150 . The sleeve  225  is positioned proximate an end portion  205  of the box member  210  to substantially prevent the surrounding wellbore from contacting and/or scratching the end portion  205 . As further shown, the sleeve  225  includes a protrusion  230  formed on a portion thereof. Generally, the sleeve  225 , with the protrusion  230 , is used to offset the connection  150  from the surrounding wellbore. In other words, the sleeve  225  and the protrusion  230  substantially block or shield the end portion  205  from contact with the surrounding wellbore as the tubular string is lowered into the wellbore. In one embodiment, the protrusion  230  may have a uniform circumferential shape on the sleeve  225 . In another embodiment, the protrusion  230  may comprise a plurality of individual projections, as illustrated in  FIG. 10 . This embodiment allows fluid flow to travel past the sleeve  225  between the plurality of individual projections. In a further embodiment, the ends (or a single end) may be chamfered or shaped in order to facilitate the lowering of the connection  150  into the wellbore. 
   The sleeve  225  may be made from any type of material that is durable yet capable of expanding, such as a metal, an elastomer, a plastic, or a polymer. The sleeve  225  may be made from a solid material as illustrated in  FIG. 3 . Alternatively, the sleeve  225  may have slots, holes, or any other geometric shapes (not shown) formed therein. As illustrated, the protrusion  230  is a rounded protrusion. However, the protrusion  230  may be any type of geometric shape without departing from principles of the present invention. 
   As illustrated, the sleeve  225  includes a tab  180  proximate an end thereof that fits between a shoulder of the pin member  110  and an end of the box member  210 . The tab  180  is configured to hold the sleeve  225  in the position illustrated in  FIG. 3 . It should be understood, however, that the sleeve  225  may be held in the position illustrated in  FIG. 3  by any means know in the art without departing from principles of the present invention. 
   As shown in  FIG. 3 , the sleeve  225  is located on the pin member  110 . In another embodiment, the sleeve  225  could be located on the box member  210  without departing from the principles of the present invention. In this embodiment, the sleeve  225  would be used to substantially block or shield the end portion  205  from contact with the surrounding wellbore as the tubular string is lowered into the wellbore. 
     FIG. 4  illustrates the threaded connection  150  with a sleeve member  250  in accordance with the present invention. For convenience, the components in  FIG. 4  that are similar to the components in  FIGS. 1 and 2  will be labeled with the same number indicator. As shown, the sleeve  250  is disposed around the pin member  110  and the box member  210  to substantially prevent the surrounding wellbore from contacting and/or scratching a portion of the connection  150 . As further shown, the sleeve  250  includes a plurality of protrusions  255  formed on a portion of the sleeve  250 . Generally, the sleeve  250 , with the protrusions  255 , is used to offset the connection  150  from the surrounding wellbore without adding substantial thickness to the connection  150 . In other words, the sleeve  250  and the protrusions  255  substantially block or shield the end portion  205  from contact with the surrounding wellbore as the tubular string is lowered into the wellbore. The sleeve  250  may be made from any type of material that is durable yet capable of expanding, such as a metal, an elastomer, a plastic, or a polymer. The sleeve  250  may be made from a solid material as illustrated in  FIG. 3 . Alternatively, the sleeve  250  may have slots, holes, or any other geometric shapes (not shown) formed therein. As shown, the protrusions  255  are rounded protrusions. However, the protrusions  255  may be any type of geometric shape without departing from principles of the present invention. 
   As illustrated, the sleeve  250  includes a tab  180  that fits between a shoulder of the pin member  110  and an end of the box member  210 . The tab  180  is configured to hold the sleeve  250  in the position illustrated in  FIG. 4 . It should be understood, however, that the sleeve  250  may be held in the position illustrated in  FIG. 4  by any means know in the art without departing from principles of the present invention. 
     FIG. 5  illustrates the threaded connection  150  in accordance with the present invention. For convenience, the components in  FIG. 5  that are similar to the components in  FIGS. 1 and 2  will be labeled with the same number indicator. As shown, the box member  210  includes a portion  185  that is recessed below a shoulder portion  190  of the pin member  110 , and as a result a portion of the pin member  110  has an outer diameter greater than an outer diameter of a portion of the box member  210  without adding substantial thickness to the connection  150 . As shown in  FIG. 5 , the portion  185  is a flat surface. It should be noted, however, that the portion  185  could be a long taper or in any geometrical configuration known in the art. The shoulder portion  190  provides a means to substantially prevent the surrounding wellbore from contacting and/or scratching an end of the box member  210 . As previously discussed, the end of the box member  210  is typically the thinnest portion of the connection  150  and a scratch on the end of the box member  210  may cause the box member  210  to split apart upon expansion of the connection  150 , thereby compromising the structural integrity of the connection  150 . Therefore, the portion  185  is recessed below the shoulder portion  190  to allow the shoulder portion  190  to substantially block or shield the vulnerable end of the box member  210  from contact with the surrounding wellbore as the tubular string is lowered into the wellbore. In another embodiment, a portion of the pin member  110  has a predetermined slope, thereby causing the pin member  110  proximate the shoulder portion  190  to have a greater outer diameter than an outer diameter of the box member  210 . In this embodiment, the portion  185  is not necessary since the shoulder portion  190  is raised relative to the box member  210  due to the predetermined slope. In a further embodiment, the shoulder portion  190  is raised relative to other portions of the pin member  110 . In this embodiment, the raised shoulder portion  190  is configured to substantially block or shield the vulnerable end of the box member  210  from contact with the surrounding wellbore as the tubular string is lowered into the wellbore. 
     FIG. 6  illustrates the threaded connection  150  in accordance with the present invention. For convenience, the components in  FIG. 6  that are similar to the components in  FIGS. 1 and 2  will be labeled with the same number indicator. As shown, the first tubular  100  includes a protrusion  265  formed therein proximate the pin member  110  and the second tubular includes a protrusion  270  formed therein proximate the box member  210 . The protrusions  265 ,  270  provide a means to substantially prevent the surrounding wellbore from contacting and/or scratching an end of the box member  210  in a similar manner as set forth above. Although the threaded connection  150  in  FIG. 6  shows the protrusion  265  and the protrusion  270 , it should be understood, however, that the threaded connection  150  may include only the protrusion  265  or only the protrusion  270 , without departing from principles of the present invention. In one embodiment, the protrusions  265 ,  270  may have a continuous circumferential shape around the tubular. In another embodiment, the protrusions  265 ,  270  may consist of a plurality of individual protrusions. This embodiment allows fluid flow to travel past the connection  150  between the individual protrusions. 
     FIG. 7  illustrates the threaded connection  150  in accordance with the present invention. For convenience, the components in  FIG. 7  that are similar to the components in  FIGS. 1 and 2  will be labeled with the same number indicator. As shown, the first tubular  100  includes a protrusion  240  formed therein proximate the pin member  110 , and the second tubular  200  includes a raised portion  245  formed therein proximate the box member  210 . The protrusion  240  and the raised portion provide a means to substantially prevent the surrounding wellbore from contacting and/or scratching an end of the box member  210  in a similar manner as set forth above. Although the threaded connection  150  in  FIG. 7  shows both the protrusion  240  and the raised portion  245 , it should be understood, however, that the threaded connection  150  may include only the protrusion  240  or only the raised portion  245 , without departing from principles of the present invention. Further, the protrusion  240  may be formed on the second tubular  200  and/or the raised portion may be formed on the first tubular  100 , without departing from principles of the present invention. In one embodiment, the protrusion  240  and/or the raised portion  245  may have a continuous circumferential shape around the tubular. In another embodiment, the protrusion  240  and/or the raised portion  245  may consist of a plurality of individual protrusions (or raised portions). This embodiment allows fluid flow to travel past the connection  150  between the individual protrusions (or raised portions). 
     FIG. 8  illustrates the threaded connection  150  with a ring member  275  in accordance with the present invention. For convenience, the components in  FIG. 8  that are similar to the components in  FIGS. 1 and 2  will be labeled with the same number indicator. As shown, the ring member  275  is disposed around the pin member  110 . The ring member  275  is positioned proximate an end portion  205  of the box member  210  to substantially prevent the surrounding wellbore from contacting and/or scratching the end portion  205  of the box member  210 . Generally, the ring member  275  is used to offset the connection  150  from the surrounding wellbore. In other words, the ring member  275  substantially blocks or shields the end portion  205  from contact with the surrounding wellbore as the tubular string is lowered into the wellbore. Additionally, the ring member  275  could be used as a torque ring. 
     FIG. 9  illustrates the threaded connection  150  in accordance with the present invention. For convenience, the components in  FIG. 9  that are similar to the components in  FIGS. 1 and 2  will be labeled with the same number indicator. As shown, the first tubular  100  includes a projection member  280  proximate the pin member  110  and the second tubular includes a projection member  285  proximate the box member  210 . The projection members  280 ,  285  provide a means to substantially prevent the surrounding wellbore from contacting and/or scratching an end of the box member  210  in a similar manner as set forth above. The projection member  280 ,  285  may be made from any type of material that is durable yet capable of expanding, such as metal, elastomeric, plastic, or a polymeric. The projection member  280 ,  285  may also be a weld bead. In one embodiment, the projection member  280 ,  285  may have a continuous circumferential shape around the tubular. In another embodiment, the projection member  280 ,  285  may consist of a plurality of individual projection members. This embodiment allows fluid flow to travel past the connection  150  between the individual projection members. 
   Although the threaded connection  150  in  FIG. 9  shows two projection members  280 ,  285 , it should be understood, however, that the threaded connection  150  may include only the projection member  280  or only the projection member  285 , without departing from principles of the present invention. Further, the threaded connection  150  may include any number of projection members without departing from principles of the present invention. 
   Although embodiments of the invention are described with reference to a box member, other types of tubular resembling a box member, such as a coupling, are also contemplated by the embodiments of the invention. 
   While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.