Note: Descriptions are shown in the official language in which they were submitted.
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Title: TORQUE SHOULDER FOR TUBULAR GOODS CONNECTION
TECHNICAL FIELD
[0001] This disclosure relates to a tubular good connection between tubular
good joints, in
particular, threaded tubular connections for tubular goods used in a wellbore.
BACKGROUND
[0002] Threaded tubular goods connections are used to couple joints of tubing
together for
use in a wellbore. A tubular goods connection couples a first tubular member
with a box
having an internal thread therein and a second tubular member with a pin
having an external
thread thereon.
[0003] Alternatively, a tubular goods connection couples a first tubular
member having a
threaded pin with a second tubular member with a pin having an external thread
there using a
coupling box connector having two boxes with mating internal threads disposed
thereon.
[0004] A tubular goods connection can include a positive stop torque shoulder
that acts as a
load-bearing surface at the tubular goods connection.
SUMMARY
[0005] This disclosure describes roughened torque shoulders in threaded
tubular good
connections for tubular goods used in wellbores.
[0006] Certain aspects of the disclosure include a tubular connection
including a first pin with
an external male threaded zone having external male threads disposed on a
portion of the
pin, and a first box with an internal female threaded zone having internal
female threads
disposed on a portion of the first box. The internal female threads are to
engage with the
external male threads of the first pin, where at least one of the first pin or
the first box includes
a first torque shoulder surface having a surface roughness greater than or
equal to 100
microns. The surface roughness may relate to the arithmetic average roughness
(Ra). The
term "micron" is used, but it is also referred to as micrometer (pm).
[0007] This, and other aspects, can include one or more of the following
features. The
surface roughness of the first torque shoulder surface can be between 100
microns and 500
microns. The first torque shoulder surface can include a knurled surface
profile. The knurled
surface profile can be continuous along the first torque shoulder surface. The
first torque
shoulder surface can include a laser cut, stamped, machined, or blasted
surface profile. One
of the first pin or the first box can include the first torque shoulder
surface, and the other of
the first pin or the first box can include a second torque shoulder surface,
the second torque
shoulder surface to engage the first torque shoulder surface. The second
torque shoulder
surface can include a surface roughness greater than or equal to 100 microns
(e.g. between
100 microns and 500 microns). The second torque shoulder surface can include a
knurled
surface profile. The knurled surface profile can be continuous along the
second torque
shoulder surface. The second torque shoulder surface can include a laser cut,
stamped,
machined, or blasted surface profile. The first torque shoulder surface and
the second torque
shoulder surface can be at a respective one of a first longitudinal end of the
first pin or a
second longitudinal end of the first box. The first longitudinal end of the
first pin can be a
distal longitudinal end of the first pin, and the second longitudinal end of
the first box can be a
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proximal longitudinal end of the first box. The first pin can include a third
torque shoulder
surface proximate to a third longitudinal end of the first pin opposite the
first longitudinal end,
the first box can include a fourth torque shoulder surface proximate to a
fourth longitudinal
end of the first box opposite the second longitudinal end, and at least one of
the third torque
shoulder surface or the fourth torque shoulder surface can include a surface
roughness
greater than or equal to 100 microns (e.g. between 100 microns and 500
microns), the fourth
torque shoulder surface to engage the third torque shoulder surface. The at
least one of the
third torque shoulder surface or the fourth torque shoulder surface can
include a knurled
surface profile. The knurled surface profile can be continuous along the at
least one of the
third torque shoulder surface or the fourth torque shoulder surface. The
tubular connection
can further include a second pin with a second external male threaded zone
having second
external male threads disposed on a portion of the second pin, and a coupling
box connector
comprising the first box and a second box, the second box having an internal
female threaded
zone having internal female threads disposed on a portion of the second box,
the internal
female threads to engage with the external male threads of the second pin,
where the first pin
has the first torque shoulder surface, and the second pin has a second torque
shoulder
surface, and where the second torque shoulder surface is to engage the first
torque shoulder
surface of the first pin. The first torque shoulder surface can include a
knurled surface profile.
The knurled surface profile can be continuous along the first torque shoulder
surface. The first
torque shoulder surface can include a laser cut, stamped, machined, or blasted
surface
profile. The second torque shoulder surface can comprises a surface roughness
greater than
or equal to 100 microns, e.g. between 100 microns and 500 microns. The second
torque
shoulder surface can include a knurled surface profile. The knurled surface
profile can be
continuous along the second torque shoulder surface. The second torque
shoulder surface
can include a laser cut, stamped, machined, or blasted surface profile.
[0008] Certain aspects of the disclosure encompass a method for forming a
tubular
connection. The method includes providing a first pin with an external male
threaded zone
having external male threads disposed on a portion of the first pin, and
providing a first box
with an internal female threaded zone having internal female threads disposed
on a portion of
the first box, the internal female threads configured to engage with the
external male threads
of the first pin. One of the first pin or the first box has a first torque
shoulder surface, and the
other of the first pin or the first box has a second torque shoulder surface.
The method also
includes engaging, with the first torque shoulder surface, the second torque
shoulder surface
to form a tubular connection, at least one of the first torque shoulder
surface or the second
torque shoulder surface including a surface roughness greater than or equal to
100 microns
(e.g. between 100 microns and 500 microns).
[0009] Some aspects of the disclosure encompass a method for forming a tubular
connection. The method includes providing a first pin with an external male
threaded zone
having external male threads disposed on a portion of the first pin, the first
pin having a first
torque shoulder surface positioned proximate to a first longitudinal end of
the first pin, and
providing a second pin with an external male threaded zone having external
male threads
disposed on a portion of the second pin, the second pin having a second torque
shoulder
surface positioned proximate to a second longitudinal end of the second pin.
At least one of
the first torque shoulder surface or the second torque shoulder surface has a
surface
roughness greater than or equal to 100 microns (e.g. between 100 microns and
500 microns).
The method also includes providing a coupling box connector having a first box
with an
internal female threaded zone having internal female threads disposed on a
portion of the first
.. box, the internal female threads to engage with the external male threads
of the first pin, and
having a second box with an internal female threaded zone having internal
female threads
disposed on a portion of the second box, the internal female threads to engage
with the
external male threads of the second pin. The method further includes engaging
the external
male threads of the first pin with the internal female threads of the first
box, engaging the
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external male threads of the second pin with the internal female threads of
the second box,
and engaging the first torque shoulder surface with the second torque shoulder
surface.
[0010] Certain aspects of the disclosure encompass a method for forming a pin
or a box for a
tubular connection. The method includes providing a pin or box having a first
torque shoulder
surface, and modifying the first torque shoulder surface to have a surface
roughness greater
than or equal to 100 microns (e.g. between 100 microns and 500 microns).
[0011] This, and other aspects, can include one or more of the following
features. Modifying
the first torque shoulder surface can include at least one of knurling, laser
cutting, stamping,
machining, or blasting the first shoulder surface to the surface roughness of
greater than or
equal to 100 microns (e.g. between 100 microns and 500 microns).
[0012] Certain aspects of the disclosure encompass a tubular connection
including a first
tubular good joint. The first tubular good joint includes an integral threaded
end including a
threaded zone having threads disposed on a portion of the integral threaded
end, and a first
torque shoulder surface, where the first torque shoulder surface includes a
surface roughness
greater than or equal to 100 microns (e.g. between 100 microns and 500
microns).
[0013] This, and other aspects, can include one or more of the following
features. The
integral threaded end can be an integral box, the threaded zone can be an
internal female
threaded zone, and the threads can be female internal threads. The integral
threaded end
can be an integral pin, the threaded zone can be an external male threaded
zone, and the
threads can be male external threads. The tubular connection can further
include a second
tubular good joint including an integral box, where the integral box can
include an internal
female threaded zone having internal female threads disposed on a portion of
the integral
box, the internal female threads to engage with the external male threads, and
a second
torque shoulder surface, the second torque shoulder surface to engage the
first torque
shoulder surface of the first tubular good joint. The second torque shoulder
surface can
include a surface roughness greater than or equal to 100 microns (e.g. between
100 microns
and 500 microns). The second torque shoulder surface can include a knurled
surface profile.
The knurled surface profile can be continuous along the second torque shoulder
surface. The
second torque shoulder surface can include a laser cut, stamped, machined, or
blasted
surface profile. The first torque shoulder surface can include a knurled
surface profile. The
knurled surface profile can be continuous along the first torque shoulder
surface. The first
torque shoulder surface can include a laser cut, stamped, machined, or blasted
surface
profile.
[0014] Some aspects of the disclosure encompass a tubular joint including a
pin with an
external male threaded zone having external male threads disposed on a portion
of the pin,
the pin having a torque shoulder surface having a surface roughness greater
than or equal to
100 microns (e.g. between 100 microns and 500 microns).
[0015] Some aspects of the disclosure encompass a tubular joint including a
box with an
internal female threaded zone having internal female threads disposed on a
portion of the
box, the box having a torque shoulder surface comprising a surface roughness
greater than
or equal to 100 microns (e.g. between 100 microns and 500 microns).
[0016] Some aspects of the disclosure encompass a coupling box connector
including a box
with an internal female threaded zone having internal female threads disposed
on a portion of
the box, the box including a torque shoulder surface having a surface
roughness greater than
or equal to 100 microns (e.g. between 100 microns and 500 microns).
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[0017] Some aspects of the disclosure encompass a torque shoulder surface for
a pin or a
box of a tubular connection, the torque shoulder surface having a surface
roughness greater
than or equal to 100 microns (e.g. between 100 microns and 500 microns).
[0018] The details of one or more implementations of the subject matter
described in this
disclosure are set forth in the accompanying drawings and the description
below. Other
features, aspects, and advantages of the subject matter will become apparent
from the
description, the drawings, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a partial cross-sectional perspective view of a first example
tubular goods
connection.
[0020] FIG. 2A is a schematic cross-sectional side view of a box of the
tubular goods
connection of Fig. 1.
[0021] FIG. 2B is a schematic cross-sectional side view of a pin of the
tubular goods
connection of Fig. 1.
[0022] FIGs. 3A and 3B are partial schematic cross-sectional side views of the
example
tubular goods connections of Fig. 1.
[0023] FIGs. 4A and 4B are partial schematic cross-sectional side views of
example tubular
goods connections.
[0024] FIG. 5 is a partial top perspective view of the box of FIG. 2A.
[0025] FIG. 6 is a graph showing a torque curve over rotations (or turns, n)
for a conventional
tubular goods connection versus a tubular goods connection with a roughened
torque
shoulder.
[0026] FIG. 7A is a flowchart describing an example method for forming a
threaded tubular
connection.
[0027] FIG. 7B is a flowchart describing an example method for forming a
threaded tubular
connection.
[0028] FIG. 8 is a flowchart describing an example method for forming a tubing
joint.
[0029] FIG. 9 is a partial cross-sectional perspective view of a second
example tubular goods
connection.
[0030] FIG. 10A is a schematic cross-sectional side view of a box of the
tubular goods
connection of Fig. 9.
[0031] FIG. 10B is a schematic cross-sectional side view of a pin of the
tubular goods
connection of Fig. 9.
[0032] FIG. 11 is a partial top perspective view of the box of FIG. 10A.
[0033] FIG. 12A is a schematic cross-sectional side view of a third example
tubular goods
connection.
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[0034] FIG. 12B is an enlarged schematic cross-sectional side view of the
example tubular
goods connection of FIG. 12A.
[0035] Like reference numbers and designations in the various drawings
indicate like
5 elements.
DETAILED DESCRIPTION
[0036] Certain terms are used herein as they would be conventionally
understood in the
tubular goods industry, particularly where threaded tubular goods are
connected in a
longitudinal (e.g., vertical) position along their respective central axis
such as when making
up a tubular goods string for lowering into a wellbore. Typically, in a male-
female threaded
tubular goods connection, the male component of the connection is referred to
as a "pin"
member at a pin and the female component is called a "box" member. In certain
implementations, a first pin and a second pin can be connected with a coupling
box
connector. A coupling box connector is a tubular element having a box at each
end thereof.
[0037] This disclosure describes tubular good connections between threaded
tubular good
joints, where one or both of pin and box of the tubular good joints or the
coupling box
connector includes a torque shoulder (i.e., positive-stop torque shoulder)
with a roughened
shoulder surface. The shoulder surface of the torque shoulder is also referred
to as torque
shoulder surface. The torque shoulder surface is mechanically roughened, for
example, via
knurling or other mechanical manipulation, such that its surface roughness is
increased. The
roughened surface of the torque shoulder can increase torque at a tubular
goods connection,
which can provide improved securement and hold of the tubular good connection,
and an
.. increased break-out torque of the tubular good connection. The roughened
shoulder surface
in a tubular good connection can increase an operative torque of the
connection due to the
engagement of the roughened torque shoulder with a corresponding abutment
surface. A
tubular good connection is formed between a threaded tubular good joint and a
corresponding tubular good joint or connector (e.g., coupling box connector),
where
.. corresponding threading and corresponding torque shoulders provide load
bearing surfaces
in the made-up tubular good connection. For example, a tubular good joint
includes threading
(for example, radially external male threading, or radially internal female
threading) and a
torque shoulder with a roughened surface. The torque shoulder surface is
roughened by
knurling, laser cutting, stamping, machining, blasting, a combination of
these, or other surface
roughening technique, so that the surface roughness of the torque shoulder is
greater than or
equal to 100 microns (e.g., between 100 microns and 500 microns). The surface
roughness
relates to the arithmetic average roughness (Ra). The term "micron" is used,
but it is also
referred to as micrometer (pm).
.. [0038] In some conventional threaded tubular good joints, torque shoulder
surfaces of
respective tubular good joints are typically smooth, for example, with a
surface roughness of
less than 40 microns. Some conventional torque shoulder surfaces typically
maintain a
default, post-machined roughness when the respective tubular good joint is
manufactured
and machined. This default roughness is less than 40 microns, such as 10 to 40
microns. In
this disclosure, at least one torque shoulder of a tubular good connection
includes a
roughened surface with a surface roughness greater than 100 microns (for
example, via
knurling, laser cutting, stamping, machining, blasting, or other technique).
In some
implementations, the surface roughness is achieved by mechanical manipulation
of the
shoulder surface, as opposed to a chemical treatment to a surface, to increase
the surface
roughness of the shoulder surface. The roughened surface can be easier to
apply and be
applied in a shorter amount of time than alternatives using a chemical or
solvent. For
example, the surface roughness of the present disclosure can be applied in a
matter of
seconds (e.g., 4 to 8 seconds), have a high accuracy of consistent and
reliable roughness
values, and can have little to no impact on health and the environment. These
characteristics
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are advantageous over chemically-applied roughening techniques, for example,
which can be
difficult to apply, are less accurate, and can have a harmful impact on health
and environment
(depending on solvent and solid particles used) as compared to the present
disclosure.
[0039] Referring now to FIG. 1, an example tubular goods connection 100 is
shown in a
partial cross-sectional perspective view. The example tubular goods connection
100 includes
a first (lower) tubular member 400 with a pin 402 at an end, a coupling box
connector 300
with a first box 301 at a first end and a second box 302 at a second end, and
a second
(upper) tubular member 200 with a pin 202. FIG. 1 shows the example tubular
goods
connection 100 as a buttress thread connection; however, the type of tubular
connection can
be different, as described in more detail later.
[0040] The first box 301 of the coupling box connector 300 is configured to
engage with and
seal to the pin 402 of the first tubular member 400, and the second box 302 of
the coupling
box connector 300 is configured to engage with and seal to the pin 202 of the
second tubular
member 200 to form the connection 100. In the example connection 100 of FIG.
1, the
coupling box connector 300, the first tubular member 400, and the second
tubular member
200 form a portion of a casing configured for implementation in a wellbore.
However, the
coupling box connector 300, the first tubular member 400 and second tubular
member 200
can form a portion of another type of tubing. FIG. 2A is a cross-sectional
side view of the box
302 at one end of the coupling box connector of FIG. 1 shown separately. FIG.
2B is a cross-
sectional side view of the pin 202 at the end of the second tubular member 200
of FIG. 1
shown separately.
[0041] As illustrated in FIG. 2A, the coupling box connector 300 includes an
internal thread
304 disposed along a portion of (e.g., an internal threaded zone of) the box
302, and includes
a first torque shoulder 306 proximate to a proximal longitudinal end of the
box 302. With
respect to central axis A-A of FIG. 2A, the box 302 includes a distal
longitudinal end at a
(vertically) upper end of the box 302, and includes the proximal longitudinal
end at a
(vertically) lower end of the box 302 opposite the distal end. The first
torque shoulder 306
includes a shoulder surface 315, or load bearing surface, that can engage
(e.g., contact) a
corresponding load bearing surface of the second tubular member 200 when the
coupling box
connector 300 and the second tubular member 200 are made-up to form the
example
connection 100. The shoulder surface 315 of the first torque shoulder 306 is
also referred to
as the first torque shoulder surface. The first torque shoulder 306 forms a
ring shape around
the inner cylindrical diameter of the box 302. The ring shape of the first
torque shoulder 306
can be continuous around an entire circumference of the ring shape. However,
in some
instances, the ring shape can be non-continuous, or segmented. In some
instances, the
torque shoulder 306 can have a flat surface profile, a tapered conical surface
profile, or a
combination of both, with respect to a radial of the coupling box connector
300.
[0042] As illustrated in FIG. 2B, the second tubular member 200 includes an
external thread
204 disposed along a portion of (e.g., an external threaded zone of) the pin
202, and a
second torque shoulder 206 proximate to a distal longitudinal end of the pin
202. With respect
to central axis A-A of FIG. 2B, the pin 202 includes the distal longitudinal
end at a (vertically)
lower end of the pin 202, and includes a proximal longitudinal end at an upper
end of the pin
202 opposite the distal end. The second torque shoulder 206 includes a
shoulder surface
215, or load bearing surface, that can engage (e.g., contact) the shoulder
surface 315 of the
first torque shoulder 306 of the coupling box connector 300 when the pin 202
and box 302 are
fully engaged. The shoulder surface 215 of the second torque shoulder 206 is
also referred to
as the second torque shoulder surface. The second torque shoulder 206 forms a
ring shape
around the cylindrical diameter of the pin 202 at the distal end of the second
tubular member
200. The ring shape of the second torque shoulder 206 can be continuous around
an entire
circumference of the ring shape. However, in some instances, the ring shape
can be non-
continuous, or segmented. In some instances, the torque shoulder 206 can have
a flat
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surface profile, a tapered conical surface profile, or a combination of both,
with respect to a
radial of the coupling box connector 300.
[0043] As mentioned earlier, the torque shoulder 206, torque shoulder 306, or
other torque
shoulder of the connection 100 can have a varying profile shape. FIGS. 1-2B
show the torque
shoulders 206 and 306 as having a substantially flat surface profile that is
(substantially or
exactly) perpendicular to center longitudinal axis A-A. However, this surface
profile shape can
vary. For example, the surface profile of any of the torque shoulders of the
connection 100
can include a slanted surface profile (i.e., that is angularly offset from a
perpendicular of the
longitudinal axis A-A), a jagged surface profile, a tapered surface profile
with a rounded or
pointed longitudinal end, a conical surface profile, a chamfered surface
profile, a combination
of these surface profiles, or another surface profile shape. In some examples,
the torque
shoulder surface can have a surface profile that is a combination tapered
profile.
[0044] The shoulder surface 315 of the first torque shoulder 306, the shoulder
surface 215 of
the second torque shoulder 206, or both the shoulder surfaces 315, 215 of the
first torque
shoulder 306 and the second torque shoulder 206 can have a surface roughness
greater than
a minimum threshold roughness, such as 100 microns. The surface roughness of
one or
more of the shoulder surfaces increases a sliding frictional force of surfaces
abutting the one
or more shoulder surfaces. The surface roughness can be attained in a variety
of ways, such
as by knurling, laser cutting, stamping, machining, blasting, a combination of
these, or
another surface roughening technique (mechanical or other), so that the
surface roughness of
the respective shoulder surface is greater than or equal to 100 microns, such
as between 100
microns and 500 microns. For example, FIG. 5 is a partial top perspective view
of the
example coupling box connector 300 with the box 302 showing the shoulder
surface 315 of
the first torque shoulder 306. As shown in FIG. 5, the shoulder surface of the
first torque
shoulder 306 includes knurling 308 in the form of slanted lines arranged
continuously along
an entirety of the shoulder surface. The example knurling 308 of FIG. 5
provides a surface
roughness of the shoulder surface that is at least 100 microns, for example,
between 100
microns and 500 microns. While FIG. 5 shows the knurling as including a
slanted-line pattern
that provides a sequence of peaks and valleys that create the surface
roughness, the knurling
can take a variety of other forms. For example, the knurling can include a
straight pattern,
angular pattern, diamond pattern, bubble pattern, or other knurling pattern
types with a
varying pitch and/or coarseness. Furthermore, while figure 5 shows the
roughening, in
particular the knurling, according to the invention on the shoulder surface of
the torque
shoulder 306 of the box 302, additionally or alternatively, the roughening, in
particular the
knurling, with the same or a different pattern, may be provided on the
shoulder surface of the
second torque shoulder 206 of the pin 202
[0045] To form the example connection 100, the integral pin 202 of the second
tubular
member 200 is inserted into the box 302 of the coupling box connector 300 to
engage the
corresponding threading and the corresponding torque shoulders. When the
integral pin 202
of the second tubular member 200 is inserted into the box 302 of the coupling
box connector
300 and the second tubular member 200 is rotated, the external thread 204 and
the internal
thread 304 threadingly engage (e.g., corresponds to and mate) to form the
tubular goods
connection 100. As the integral pin 202 is rotated relative to the box 302
toward a maximum
rotation for complete engagement, the respective torque shoulder surfaces
approach and
abut each other. Upon a complete rotational installment of the pin 202 with
the box 302, the
shoulder surface 315 of the first torque shoulder 306 engages with (e.g.,
contacts, or abuts)
the shoulder surface 215 of the second torque shoulder 206. FIG. 3A is a
partial schematic
cross-sectional side view of the example tubular connection 100 of FIGs. 1-2B.
FIG. 3B
shows in detail the coupling of the integral pin 202 of the second tubular
member 200 and the
box 302 of the coupling box connector 300. This coupling of the coupling box
connector 300
and the second tubular member 200 is referred to in the art as making-up the
tubular goods
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connection 100. When the tubular goods connection 100 is made-up, the internal
thread 304
engages the external thread 204 via an interference fit of mating threads, and
the first torque
shoulder 306 engages (i.e., contacts) the second torque shoulder 206 via an
interference fit of
the contacting shoulder surfaces 315, 215. In some implementations, the
internal thread 304
sealingly engages the external thread 204, for example, along all or a portion
of the internal
and/or external threaded zones. Alternatively or additionally, sealing of the
connection is
provided by an elastomeric seal or a so-called metal-to-metal seal. Examples
of connections
with a metal-to-metal seal in combination with torque shoulder surfaces are
illustrated in U.S.
Patent Publication No. U52004/0108719 to Carcagno et al., incorporated herein
by reference
in its entirety.
[0046] As used herein, "make-up" or in the past tense "being made up" refers
to the
procedure of inserting into and engaging the pin 202 of the second tubular
member 200 with
the box 302 of the first tubular member 300, and screwing the members together
through
.. torque and rotation to obtain a "made-up connection" where the respective
threadings engage
each other and the respective torque shoulders engage each other. In some
implementations,
the surface roughness of one or more shoulder surfaces of the torque shoulders
provides an
increased resistance to jump-out, or break-out, during use (i.e., increases
break-out torque to
disconnect the example connection). The use of the threaded connection in
combination with
the roughened torque shoulders can be used in applications (such as downhole
wellbore
operations) where additional torque is required, such as in horizontal wells,
deviated wells, or
other wellbore locations. In certain implementations, the additional torque
gained from the
roughened torque shoulders allows for less torque to be required by the
respective mating
threads of the connection. For example, the roughened torque shoulders can be
implemented
in thin-walled pipes where the radial dimension of the abutment surface is
shorter than in
thick-walled pipes. In other words, utilizing roughened torque shoulders
provides an amount
of torque to the tubular goods connection that allows for the use of a casing
or tubing with
thinner walls with shorter threaded zones, since the roughened torque
shoulders and the
shorter threaded zones still provides sufficient minimum torque (i.e., minimum
operative
torque) to the tubular goods connection.
[0047] FIGS. 1-3B show the torque shoulders 206 and 306 as having a
substantially flat
surface profile that is (substantially or exactly) perpendicular to center
longitudinal axis A-A.
However, this surface profile shape can vary. For example, the surface profile
of any of the
torque shoulders of the connection 100 can include a slanted surface profile
(i.e., that is
angularly offset from a perpendicular of the longitudinal axis A-A), a jagged
surface profile, a
tapered surface profile with a rounded or pointed longitudinal end, a conical
surface profile, a
chamfered surface profile, a combination of these surface profiles, or another
surface profile
shape. A variant of the example tubular connection 100 is illustrated in FIG
4A. In FIG. 4A, a
partial schematic cross-sectional side view of an example tubular connection
100' is shown
that corresponds to the example tubular connection 100 shown in FIG. 3B,
except that the
torque shoulders 206' and 306' of the connection 100' include a slanted
surface profile that is
angularly offset from a perpendicular of the longitudinal axis A-A. In some
instances, the
coupling box connector 300, the second tubular joint 200, or both the coupling
box connector
300 and the second tubular joint 200 include a torque shoulder on both
longitudinal ends of
the respective box 302 or pin 202. For example, FIG. 4B is a partial schematic
cross-sectional
side view of an example tubular connection 100". The example tubular
connection 100" of
FIG. 4B is similar to the example tubular connection 100' of FIG. 4A, except
the coupling box
connector 300" includes two torque shoulders on opposite longitudinal ends of
the box 302",
and the second tubular good joint 200" includes two torque shoulders on
opposite longitudinal
ends of the pin 202". In the example connection 100" of FIG. 4B, the coupling
box connector
300" includes the first torque shoulder 306' on the proximal longitudinal end
of the box 302",
and further includes a third torque shoulder 310 at the distal end of the box
302'. The second
tubular good joint 200" includes the second torque shoulder 206' on the distal
longitudinal
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end of the pin 202", and further includes a fourth torque shoulder 210 on the
proximal
longitudinal end of the pin 202". The third torque shoulder 310 includes a
shoulder surface
325, and the fourth torque shoulder 210 includes a shoulder surface 225. The
shoulder
surface 325 of the third torque shoulder 310 is also referred to as the third
torque shoulder
surface. The shoulder surface 225 of the fourth torque shoulder 210 is also
referred to as the
fourth torque shoulder surface. The shoulder surface 325 of the third torque
shoulder 310 can
engage (e.g., contact) the shoulder surface 225 of the fourth torque shoulder
210 when the
pin 202" and box 302" are fully engaged. One or more or all of the shoulder
surfaces 315',
215', 325, 225 of the first torque shoulder 306', second torque shoulder 206',
third torque
shoulder 310, or fourth torque shoulder 210 can have a surface roughness
greater than the
minimum threshold roughness (e.g., 100 microns), as described earlier.
[0048] The third torque shoulder 310 forms a ring shape about the central axis
A-A on the
box 302", and the ring shape of the third torque shoulder 310 can be
continuous around an
entire circumference of the ring shape. However, in some instances, the ring
shape can be
non-continuous, or segmented. Similarly, the fourth torque shoulder 210 forms
a ring shape
about the central axis A-A on the pin 202", and the ring shape of the fourth
torque shoulder
210 can be continuous around an entire circumference of the ring shape.
However, in some
instances, the ring shape can be non-continuous, or segmented. As described
earlier, the
surface profile of the torque shoulder 310 can vary. For example, the torque
shoulder 310 can
have a flat surface profile, a tapered conical surface profile, or a
combination of both, with
respect to a radial of the coupling box connector 300".
[0049] Although herein above, under reference to FIGs. 1, 2A to 3B, and 5, the
coupling
between one box 302 at one end of the coupling box connector 300 and the pin
202 of the
second tubular member 200 has been described, the same applies to the coupling
between
the other box 301 at the other end of the coupling box connector 300 and the
pin 402 of the
first tubular member 400. The same apples to connection 100' of FIG. 4A and
connection
100" of FIG 4B.
[0050] The coupling box connector 300 includes a radially inward flange 307
between the first
box 301 and the second box 302 that can abut and engage shoulder surface 406
of the pin
402 of the first tubular member 400 and shoulder surface 206 of the pin 202 of
the second
tubular member 200.
[0051] Referring to the tubular goods connection 100 of FIGs. 1 to 3B and 5
(or connection
100' of FIG. 4A and connection 100" of FIG 4B), the first tubular member 400
can be a first
joint of casing 400 (or joint of tubing) having the pin 402 and the external
male thread 404
disposed longitudinally on a portion of the pin 402. The external thread 404
is configured to
sealingly engage with the internal female thread 305 of the box 301 of the
coupling box
connector 300. The second tubular member 200 can be a second joint of casing
200 (or joint
of tubing) having the pin 202 with external male threading 204 disposed
longitudinally on a
portion of the pin 202. The external thread 204 is configured to sealingly
engage with the
internal female thread 304 of the box 302 of the coupling box connector 300.
The second joint
of casing 200 has an internal diameter D1 of an inner surface of the second
joint of casing
200 that can be the same as an internal diameter of an inner surface of the
first joint of casing
400. The tubular connection 100 can be made up to connect the first tubular
good joint 400
and the second tubular good joint 200 to the coupling box connector 300.
[0052] Referring to the geometry of threads, the following is a brief
discussion of standard
industry terminology. For example, the term "load flank" designates the
sidewall surface of a
thread that faces away from the outer end of the respective pin or coupling
member on which
the thread is formed and supports all or a portion of the weight (i.e.,
tensile load) of the lower
tubular member hanging in the wellbore. Similarly, the term "stab flank"
designates the
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sidewall surface of the thread that faces toward the outer end of the
respective pin or coupling
member and supports forces compressing the joints toward each other such as
the weight of
the upper tubular member during the initial make-up of the joint.
5 [0053] Vanishing threads: The portion at the end of the threaded portion
in a threaded
connection, in which threads are not cut full depth, but which provides a
transition between
full formed threads and pipe body. Theoretically, the vanishing point is the
point in which the
tapered pitch diameter of the thread intersects the outside pipe diameter
("OD").
10 [0054] Additionally, a thread "lead" refers to the differential distance
between components of
a thread on consecutive threads. As such, the "stab lead" is the distance
between stab flanks
of consecutive thread pitches along the axial length of the connection. A
"load lead" is the
distance between load flanks of consecutive thread pitches along the axial
length of the
connection.
[0055] FIG. 6 is a graph of an example torque curve 600 showing the torque of
a tubular joint
connection over rotations (or turns, n), more particularly, for a first,
conventional tubular
goods connection versus a tubular goods connection with a roughened torque
shoulder.
Torque plot 602 shows an example torque curve for an example conventional
tubular good
connection (first connection), for example, that excludes a roughened torque
shoulder. The
torque plot 602 shows the example torque curve of making up a pin and a box
for an example
conventional tubular good connection. Torque plot 604 shows an example torque
curve for an
example tubular good connection (second connection) that includes a roughened
torque
shoulder, for example, such as example tubular good connection 100, 100',
100", as
described earlier. The torque plot 604 shows the example torque curve of
making up a pin
and a box, e.g. pin 202 of the second tubular member 200 and second box 302 of
coupling
box connector 300. The same example torque curve could be for making up the
pin 402 of
the first tubular member 400 and the first box 301 of the coupling box
connector 300.
[0056] The torque curve 600 shows the torque of the respective tubular good
connection
between an initial point of contact (where respective threads of the
connection begin to
engage each other) and a final position of the connection (where the
respective threads and
respective torque shoulders of the connection are fully engaged). As described
in more detail
later, the torque plots 602 and 604 include a starting point, an inflection
point (where
corresponding torque shoulders begin to contact each other), and a final,
fully made-up point.
[0057] Point 602a of torque plot 602 indicates the starting point for the make-
up operation of
the first tubular good connection. Point 602b is referred to as the
"shouldering torque," and
indicates the instance where a torque shoulder of a box of the connection
abuts (i.e., first
contacts) a torque shoulder of a pin of the connection. Point 602c indicates
the first operative
torque 606 of the first connection, which refers to a torque value provided by
the first
connection when fully made-up (i.e., the end of the fastening operation
between the pin and
the box of the first connection). The operative torque can be provided by a
manufacturer of
the connection,
[0058] Point 604a of torque plot 604 indicates the starting point for the make-
up operation of
the second tubular good connection. Point 604b is the shouldering torque of
the second
connection, and indicates the instance where the torque shoulder with a
roughened shoulder
surface of a first tubular good joint of the second connection abuts (i.e.,
first contacts) a
corresponding torque shoulder of a second tubular good joint of the second
connection. Point
604c indicates the second operative torque 608 of the second connection, which
refers to the
torque value provided by the second connection when fully made-up (i.e., the
end of the
fastening operation between the first tubular good joint and the second
tubular good joint of
the second connection).
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[0059] In the example torque curve 600 of FIG. 6, the torque plots 602 and 604
are
representative of the first connection and the second connection having the
same size
threading, same location of respective torque shoulders, and other
similarities, with the only
primary difference being that the second connection (torque plot 604) includes
a roughened
shoulder surface (e.g., surface roughness greater than or equal to 100
microns), whereas the
first connection has a conventional shoulder surface (e.g., surface roughness
of about 20
microns).
[0060] The difference in the torque values at point 602b and at point 602c
(torque at 602b
subtracted by torque at 602c) is referred to as "delta torque" for the first
connection. Similarly,
the difference in the torque values at point 604b and at point 604c (torque at
604b subtracted
by torque at 604c) is referred to as delta torque for the second connection.
The segment of
torque plot 602 between points 602a and 602b represents the gradual increase
in torque of
the first connection as corresponding threads are engaging. In this segment
between 602a
.. and 602b, the main resistance to the application of torque is the radial
interference exerted by
radial surfaces in contact with each other. Similarly, the segment of torque
plot 604 between
points 604a and 604b represents the gradual increase in torque of the second
connection as
corresponding threads are engaging. In this segment between 604a and 604b, the
main
resistance to the application of torque is the radial interference exerted by
radial surfaces in
contact with each other. As shown in the example torque curve 600, the segment
between
602a and 602b and the segment between 604a and 604b are (substantially or
exactly) the
same.
[0061] Points 602b and 604b are inflection points in the respective torque
plots, where torque
.. more steeply increases as the turns increase. The segment of torque plot
602 between points
602b and 602c shows the sharp increase in torque caused by the energization of
the
abutment shoulders of the first connection. The torque value drastically
increases in a fraction
of a turn compared to the preceding segment between points 602a and 602b, for
example,
because axial interference is overcome, which consumes the corresponding
torque energy
that is stored as elastic energy in the first connection.
[0062] The segment of torque plot 604 between points 604b and 604c show a
sharp increase
in torque caused by the energization of the abutment shoulders of the second
connection.
This segment between 604b and 604c of torque plot 604 is steeper and reaches a
higher
operative torque 608 than the segment between 602b and 602b of torque plot
602, for
example, because the surface roughness of the torque shoulder of the second
connection
provides an increased friction between the abutted shoulder surfaces, thereby
increasing the
torque energy that is stored as elastic energy in the second connection. As a
result, the
operative torque 608 of the second connection is greater than the operative
torque 606 of the
first connection, and the delta torque of the second connection is larger than
the delta torque
of the first connection.
[0063] Generally, the delta torque can be a measure of the resistance of the
connection to
break out or undergo undesired unfastening. The delta torque of the second
connection is
larger than the delta torque of the first connection, so the second connection
has a larger
break-out torque, and has increased resistance to undesired unfastening, than
the first
connection. The value of the operative torque 608 of the second connection can
be increased
(from the first operative torque 606) without the risk to reach the material
plastic limit 610 of
the material (e.g., steel or other metal) that makes up the tubular good
joints of the second
.. connection. The surface modification (i.e., surface roughening) of the
torque shoulder
generates enhanced tribological properties of the contact surfaces of the
torque shoulder,
which promotes an advantageous redistribution of stresses and deformations in
the
connection.
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[0064] FIG. 7A is a flowchart describing an example method 700 for forming a
connection,
such as the tubular goods connection 100 of FIGs. 1-3B, tubular goods
connection 100' of
FIG. 4A, or tubular goods connection 100" of FIG. 4B. At 702, a first pin is
provided, the first
pin including an external male threaded zone having external male threads
disposed on a
portion of the first pin. At 704, a first box is provided, the first box
including an internal female
threaded zone having internal female threads disposed on a portion of the
first box. The
internal female threads are to engage with the external male threads of the
first pin, where
one of the first pin and or the first box has a first torque shoulder surface,
and the other of the
first pin or the first box has a second torque shoulder surface. At 706, the
second torque
shoulder surface engages with the first torque shoulder surface to form a
tubular connection,
where at least one of the first torque shoulder surface or the second torque
shoulder surface
includes a surface roughness greater than or equal to 100 microns.
[0065] FIG. 7B is a flowchart describing an example method 720 for forming a
tubular
connection, such as the tubular goods connection 100 of FIGs. 1-3B, tubular
goods
connection 100' of FIG. 4A, or tubular goods connection 100" of FIG. 4B. At
722, a first pin
with an external male threaded zone having external male threads disposed on a
portion of
the first pin is provided, the first pin having a first torque shoulder
surface positioned
proximate to a first longitudinal end of the first pin. At 724, a second pin
with an external male
threaded zone having external male threads disposed on a portion of the second
pin is
provided, the second pin having a second torque shoulder surface positioned
proximate to a
second longitudinal end of the second pin. At least one of the first torque
shoulder surface or
the second torque shoulder surface includes a surface roughness greater than
or equal to
100 microns. At 726, a coupling box connector is provided, the coupling box
connector having
a first box with an internal female threaded zone having internal female
threads disposed on a
portion of the first box, the internal female threads configured to engage
with the external
male threads of the first pin, and having a second box with an internal female
threaded zone
having internal female threads disposed on a portion of the second box, where
the internal
female threads are configured to engage with the external male threads of the
second pin. At
728, the external male threads of the first pin are engaged with the internal
female threads of
the first box. At 730, the external male threads of the second pin are engaged
with the
internal female threads of the second box. At 732, the first torque shoulder
surface is
engaged with the second torque shoulder surface.
[0066] FIG. 8 is a flowchart describing an example method 800 for forming a
tubing joint such
as the tubular joints 200, 200', 200", 400, or for forming a coupling box
connector 300', 300"
of FIGs. 1-5B. At 802, a pin or box is provided, the pin or the box having a
first torque
shoulder surface. At 804, the first torque shoulder surface is modified to
have a surface
roughness greater than or equal to 100 microns.
[0067] The tubular connections 100, 100', and 100"described herein above under
reference
to figures 1 to 4B are so-called "threaded and coupled" connections, wherein a
pin at an end
of a first tubular joint and a pin at and end of a second tubular joint are
coupled via a coupling
box connector having a box at both ends thereof. Alternatively, a tubular
connection in
accordance with the present invention is a so-called "integral" connection,
wherein an integral
box at an end of a first tubular joint is coupled to an integral pin at an end
of a second tubular
joint. An example of a tubular connection in accordance with the present
invention that is of
the "integral" type, is described herein below under reference to FIG. 9.
[0068] Referring now to FIG. 9, an example tubular goods connection 1100 is
shown in a
partial cross-sectional perspective view. The example tubular goods connection
1100
includes a first (lower) tubular member 1300 with an integral box 1302, and a
second (upper)
tubular member 1200 with an integral pin 1202.
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[0069] FIG. 9 shows the example tubular goods connection 1100 as a wedge
thread
connection; however, the type of tubular connection can be different. The
thread profile can
be a buttress profile such as in the example connections 100, 100' and 100"
described herein
above. Furthermore, the threaded connection can be other thread profiles that
can be used in
combination with a torque shoulder.
[0070] Examples of connections with a wedge thread profile in combination with
a torque
shoulder are illustrated in U.S. Patent Publication No. U52010/0181763 to
Mallis et al.,
incorporated herein by reference in its entirety.
[0071] The box 1302 of the first tubular member 1300 is configured to engage
with and seal
to the pin 1202 of the second tubular member 1200 to form the connection 1100.
In the
example connection 1100 of FIG. 9, the first tubular member 1300 and second
tubular
member 1200 form a portion of a casing configured for implementation in a
wellbore.
However, the first tubular member 1300 and second tubular member 1200 can form
a portion
of another type of tubing. FIG. 10A is a cross-sectional side view of the
first tubular member
1300 of FIG. 9 shown separately. FIG. 10B is a cross-sectional side view of
the second
tubular member 1200 of FIG. 9 shown separately.
[0072] As illustrated in FIG. 10A, the first tubular member 1300 includes an
internal wedge
thread 1304 disposed along a portion of (e.g., an internal wedge threaded zone
of) the box
1302, and includes a first torque shoulder 1306 proximate to a proximal
longitudinal end of
the box 1302. With respect to central axis A-A of FIG. 10A, the box 1302
includes a distal
longitudinal end at a (vertically) upper end of the box 1302, and includes the
proximal
longitudinal end at a (vertically) lower end of the box 1302 opposite the
distal end. The first
torque shoulder 1306 includes a shoulder surface 1315, or load bearing
surface, that can
engage (e.g., contact) a corresponding load bearing surface of the second
tubular member
1200 when the first tubular member 1300 and the second tubular member 1200 are
made-up
to form the example connection 1100. The shoulder surface 1315 of the first
torque shoulder
1306 is also referred to as the first torque shoulder surface. The first
torque shoulder 1306
forms a ring shape around the inner cylindrical diameter of the box 1302. The
ring shape of
the first torque shoulder 1306 can be continuous around an entire
circumference of the ring
shape. However, in some instances, the ring shape can be non-continuous, or
segmented. In
some instances, the torque shoulder 1306 can have a flat surface profile, a
tapered conical
surface profile, or a combination of both, with respect to a radial of the
tubular member 1300.
[0073] As illustrated in FIG. 10B, the second tubular member 1200 includes an
external
wedge thread 1204 disposed along a portion of (e.g., an external wedge
threaded zone of)
the pin 1202, and a second torque shoulder 1206 proximate to a distal
longitudinal end of the
pin 1202. With respect to central axis A-A of FIG. 10B, the pin 1202 includes
the distal
longitudinal end at a (vertically) lower end of the pin 1202, and includes a
proximal
longitudinal end at an upper end of the pin 1202 opposite the distal end. The
second torque
shoulder 1206 includes a shoulder surface 1215, or load bearing surface, that
can engage
(e.g., contact) the shoulder surface 1315 of the first torque shoulder 1306 of
the first tubular
member 1300 when the pin 1202 and box 1302 are fully engaged. The shoulder
surface 1215
of the second torque shoulder 1206 is also referred to as the second torque
shoulder surface.
The second torque shoulder 1206 forms a ring shape around the cylindrical
diameter of the
pin 1202 at the distal end of the second tubular member 1200. The ring shape
of the second
torque shoulder 1206 can be continuous around an entire circumference of the
ring shape.
However, in some instances, the ring shape can be non-continuous, or
segmented. In some
instances, the torque shoulder 1206 can have a flat surface profile, a tapered
conical surface
profile, or a combination of both, with respect to a radial of the tubular
member 1300.
[0074] As mentioned earlier, the torque shoulder 1206, torque shoulder 1306,
or other torque
shoulder of the connection 1100 can have a varying profile shape. FIGS. 9-10B
show the
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torque shoulders 1206 and 1306 as having a substantially flat surface profile
that is
(substantially or exactly) perpendicular to center longitudinal axis A-A.
However, this surface
profile shape can vary. For example, the surface profile of any of the torque
shoulders of the
connection 1100 can include a slanted surface profile (i.e., that is angularly
offset from a
perpendicular of the longitudinal axis A-A), a jagged surface profile, a
tapered surface profile
with a rounded or pointed longitudinal end, a conical surface profile, a
chamfered surface
profile, a combination of these surface profiles, or another surface profile
shape. In some
examples, the torque shoulder surface can have a surface profile that is a
combination
tapered profile, such as illustrated in U.S. Patent No. 9,752,710.
[0075] The shoulder surface 1315 of the first torque shoulder 1306, the
shoulder surface
1215 of the second torque shoulder 1206, or both the shoulder surfaces 1315,
1215 of the
first torque shoulder 1306 and the second torque shoulder 1206 can have a
surface
roughness greater than a minimum threshold roughness, such as 100 microns. The
surface
roughness of one or more of the shoulder surfaces increases a sliding
frictional force of
surfaces abutting the one or more shoulder surfaces. The surface roughness can
be attained
in a variety of ways, such as by knurling, laser cutting, stamping, machining,
blasting, a
combination of these, or another surface roughening technique (mechanical or
other), so that
the surface roughness of the respective shoulder surface is greater than or
equal to 100
microns, such as between 100 microns and 500 microns. For example, FIG. 11 is
a partial top
perspective view of the example first tubular member 1300 with the box 1302
showing the
shoulder surface 1315 of the first torque shoulder 1306. As shown in FIG. 11,
the shoulder
surface of the first torque shoulder 1306 includes knurling 1308 in the form
of slanted lines
arranged continuously along an entirety of the shoulder surface. The example
knurling 1308
of FIG. 11 provides a surface roughness of the shoulder surface that is at
least 100 microns,
for example, between 100 microns and 500 microns. While FIG. 11 shows the
knurling as
including a slanted-line pattern that provides a sequence of peaks and valleys
that create the
surface roughness, the knurling can take a variety of other forms. For
example, the knurling
can include a straight pattern, angular pattern, diamond pattern, bubble
pattern, or other
knurling pattern types with a varying pitch and/or coarseness.
[0076] To form the example connection 1100, the integral pin 1202 is inserted
into the
integral box 1302 to engage the corresponding threading and the corresponding
torque
shoulders. When the integral pin 1202 of the second tubular member 1200 is
inserted into the
integral box 1302 of the first tubular member 1300 and the second tubular
member 1200 is
rotated, the external wedge thread 1204 and the internal wedge thread 304
threadingly
engage (e.g., corresponds to and mate) to form the tubular goods connection
1100. As the
integral pin 1202 is rotated relative to the integral box 1302 toward a
maximum rotation for
complete engagement, the respective torque shoulder surfaces approach and abut
each
other. Upon a complete rotational installment of the pin 1202 with the box
1302, the shoulder
surface 1315 of the first torque shoulder 1306 engages with (e.g., contacts,
or abuts) the
shoulder surface 1215 of the second torque shoulder 1206. When the tubular
goods
connection 1100 is made-up, the internal wedge thread 1304 engages the
external wedge
thread 1204 via an interference fit of the mating wedge threads, and the first
torque shoulder
1306 engages (i.e., contacts) the second torque shoulder 1206 via an
interference fit of the
contacting shoulder surfaces 1315, 1215. In some implementations, the internal
wedge
thread 1304 sealingly engages the external wedge thread 1204, for example,
along all or a
portion of the internal and/or external threaded zones.
[0077] Wedge threads, regardless of a particular type, increase in width W1,
W2 in opposite
directions on a pin member and a box member. In preferred embodiments, the
threads have
a dovetail wedge thread profile characterized by having a width of a tooth
crest VVTC wider
than a width of teeth VVTR, so it can also be said that both flanks, stab and
load flanks, are
negative. In some examples, the threads can take on other profiles and shapes.
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[0078] Depending on the type of the wedge thread (interference type or
clearance type), the
wedging between flanks will be generated in different ways. The wedging effect
generated on
interference wedge threads is due to specific axial interference fit between
mating load and
stab flanks. Moreover, the wedging effect can also be achieved without this
specific design
5 interference (e.g. clearance wedge type) by, for example, thread
drunkenness and/or radial
interference, for example by radial interference between crests and roots.
[0079] Regardless of the type of the wedge thread, e.g. clearance wedge, or
interference
wedge, corresponding flanks come closer to each other (i.e., clearance
decreases or
10 interference increases) during make-up. Indeterminate make-up allows for
the flank
interference to be increased by increasing the make-up torque on the
connection. This
increased make up torque will produce some drawbacks because said increased
make up
torque will generate a higher general stress state due to the higher flank to
flank interference
that will lead to high contact pressures between sliding elements (during make-
up), and also
15 between assembly elements (e.g., at the end of make-up).
[0080] Depending on the type of the wedge thread, the wedging between flanks
will be
generated in different ways. The wedging effect generated on interference
wedge threads is
due to specific interference fit between at least part of mating load and stab
flanks of at least
part of the threaded portion.
[0081] An example making up of the connection 1100 is as follows. Internal
thread of box
1302 has stab flanks, load flanks, roots, and crests. The thread increases in
width
progressively at a uniform rate in one direction substantially the entire
helical length of thread.
External thread of pin 1202 has stab flanks, load flanks, roots, and crests.
The thread
increases in width progressively at a uniform rate in the other direction
substantially the entire
helical length of thread. The oppositely increasing thread widths and the
taper of threads,
cause the complementary roots and crests of the respective threads to move
into
engagement during make-up of the connection 1100. Root and crest engagement is
followed
by the moving of complementary stab and load flanks into engagement upon make-
up of the
connection. The moving of complementary flanks, roots and crests into
engagement forms
sealing surfaces that resist the flow of fluids between the threads. The
torque shoulder
surfaces of the torque shoulders 1206 and 1306 move into engagement upon make-
up of the
connection. The torque shoulder engagement may occur simultaneously with the
stab and
load flanks moving into engagement. Alternatively, the stab and load flanks
may move into
engagement after root and crest engagement during make-up of the connection
and followed
by the torque shoulder surface engagement upon make-up of the connection. As
an
alternative, upon initial make-up the torque shoulder surfaces are at an axial
distance from
each other. The torque shoulder surfaces may then during use, i.e. in the
well, engage in
case torque applied to the connection exceeds the torque resistance of the
wedge thread.
The torque shoulder surfaces thus serve as a backup for over-torque conditions
during use.
[0082] FIGs. 12A and 12B show a further variant of the example tubular
connections of FIGs.
1 to 11. The example tubular connection 500 of FIGs 12A and 12B is a threaded
and coupled
type connection similar to the example tubular connections 100, 100' and 100"
shown in and
described under reference to FIGs. 1 to 8, however the coupling box connector
502 of tubular
connection 500 does not have a radially inward flange between the first box
504a and the
second box 504b. Furthermore, the thread profile of the tubular connection 500
is a wedge
profile like the thread profile of example connection 1100 of figures 9 to 11.
[0083] FIG. 12A is a schematic cross-sectional side view of an example tubular
good
connection 500 with an example coupling box connector 502. FIG. 12B is an
enlarged
schematic cross-sectional side view of the example made-up tubular good
connection 500 of
FIG. 12A. The first box 504a of the coupling box connector 502 is configured
to engage with
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and seal to the first pin 512 of the first tubular member 510, and the second
box 504b of the
coupling box connector 502 is configured to engage with and seal to the second
pin 1522 of
the second tubular member 520 to form the example connection 500. The coupling
box
connector 502 includes a first internal wedge thread 506a disposed along a
portion of (e.g., a
first internal wedge threaded zone of) the first box 504a, and includes a
second internal
wedge thread 506b disposed along a portion of (e.g., a second internal wedge
threaded zone
of) the second box 504b.
[0084] The first tubular member 510 includes a first external thread 514
disposed along a
portion of (e.g., a first external wedge threaded zone of) the first pin 512,
and a first torque
shoulder 516 proximate to a distal longitudinal end of the first pin 512. With
respect to central
axis A-A of FIG. 12A, the first pin 512 includes the distal longitudinal end
at a terminal end of
the pin 512, and includes a proximal longitudinal end at an opposite
longitudinal end of the
pin 512 opposite the distal end. The first torque shoulder 516 includes a
shoulder surface
515, or load bearing surface, that can engage (e.g., contact) a shoulder
surface of the second
tubular member 520. The shoulder surface 515 of the first torque shoulder 516
is also
referred to as the first torque shoulder surface. The first torque shoulder
516 forms a ring
shape around the cylindrical diameter of the pin 512 at the distal end of the
first tubular
member 510. The ring shape of the first torque shoulder 516 can be continuous
around an
entire circumference of the ring shape. However, in some instances, the ring
shape can be
non-continuous, or segmented. As described earlier, the surface profile of the
torque shoulder
516 can vary. For example, the torque shoulder 516 can have a flat surface
profile, a tapered
conical surface profile, or a combination of both, with respect to a radial of
the tubular
member 510.
[0085] The second tubular member 520 includes a second external wedge thread
524
disposed along a portion of (e.g., a second external wedge threaded zone of)
the second pin
522, and a second torque shoulder 526 proximate to a distal longitudinal end
of the fourth pin
522. With respect to central axis A-A of FIG. 12A, the second pin 522 includes
the distal
longitudinal end at a terminal end of the pin 522, and includes a proximal
longitudinal end at
an opposite longitudinal end of the pin 522 opposite the distal end. The
second torque
shoulder 526 includes a shoulder surface 535, or load bearing surface, that
can engage (e.g.,
contact) the shoulder surface 515 of the first torque shoulder 516 of the
first tubular member
510. The shoulder surface 535 of the second torque shoulder 526 is also
referred to as the
.. second torque shoulder surface. The second torque shoulder 526 forms a ring
shape around
the cylindrical diameter of the second pin 522 at the distal end of the second
tubular member
520. The ring shape of the second torque shoulder 526 can be continuous around
an entire
circumference of the ring shape. However, in some instances, the ring shape
can be non-
continuous, or segmented. As described earlier, the surface profile of the
torque shoulder 526
can vary. For example, the torque shoulder 526 can have a flat surface
profile, a tapered
conical surface profile, or a combination of both, with respect to a radial of
the tubular
member 520.
[0086] The shoulder surface 515 of the first torque shoulder 516, the shoulder
surface 535 of
the second torque shoulder 526, or both the shoulder surfaces 515, 535 of the
first torque
shoulder 516 and the second torque shoulder 526 can have a surface roughness
greater than
the minimum threshold roughness, described earlier.
[0087] To form the example connection 500, the first pin 512 is inserted into
the first box
504a to engage the corresponding threading, and the second pin 522 is inserted
into the
second box 504b to engage the corresponding threading, and the first torque
shoulder 516
and the second torque shoulder 526 engage (i.e., contact) each other. As the
pins 512 and
522 are rotated relative to the coupling box connector 502 toward a complete
engagement,
the respective torque shoulder surfaces of the pins 512 and 522 approach each
other. Upon a
CA 03142858 2021-12-07
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17
complete rotational installment of the first pin 512 with the first box 504a
and the second pin
522 with the second box 504b, the shoulder surface 515 of the first torque
shoulder 516
engages with (e.g., contacts) the shoulder surface 535 of the second torque
shoulder 526.
FIG. 12B shows this contacting engagement. The coupling of the first tubular
member 510
and the second tubular member 520 with the coupling box connector 502 can be
referred to
in the art as making-up the tubular goods connection 500. When the example
tubular goods
connection 500 is made-up, the first internal wedge thread 506a engages the
first external
wedge thread 514 via an interference fit of the mating wedge threads, the
second internal
wedge thread 506b engages the second external wedge thread 524 via an
interference fit of
the mating wedge threads, and the first torque shoulder 516 engages (i.e.,
contacts) the
second torque shoulder 526 via an interference fit of the contacting shoulder
surfaces 515,
535.
[0088] Similar to the example connections 100, 100', and 100", in some
implementations, the
coupling box connector 502 can include a positive-stop torque shoulder that
engages one or
both of the shoulder surfaces of the first tubular member 510 and/or second
tubular member
520. For example, the coupling box connector 502 can include a radially inward
flange
between the first box 504a and the second box 504b that can abut and engage
the shoulder
surfaces 515, 535 of the first torque shoulder 516 and the second torque
shoulder 526
(instead of the first torque shoulder 516 directly abutting and engaging the
second torque
shoulder 526).
[0089] In FIGs. 12A and 12B the example connection 500 is shown in made-up
state. As an
alternative, upon initial make-up, the torque shoulder surfaces are at an
axial distance from
each other. The torque shoulder surfaces may then during use, i.e. in the
well, engage in
case torque applied to the connection exceeds the torque resistance of the
wedge thread.
The torque shoulder surfaces thus serve as a backup for over-torque conditions
during use.
Examples of connections with wedge threads wherein upon make-up torque
shoulder
surfaces are at an axial distance from each other are illustrated in U.S.
Patent Publication No.
U52017/0314596 to Harvey et al., incorporated herein by reference in its
entirety.
[0090] FIGs. 12A and 12B show the example connection 500 as a wedge thread
connection;
however, the type of tubular connection can be different. The thread profile
can be a buttress
profile such as in the example connections 100, 100' and 100" described herein
above.
Furthermore, the thread profile of the connection can be other thread profiles
that can be
used in combination with a torque shoulder.
[0091] A number of implementations have been described. Nevertheless, it will
be
understood that various modifications may be made without departing from the
spirit and
scope of the disclosure. In particular, the thread profile of the connection
can be other thread
profiles that can be used in combination with a torque shoulder. Furthermore,
the torque
shoulder surfaces can be at another location than at a longitudinal end of a
pin or a box. The
torque shoulder surfaces can be located at a location between the longitudinal
ends of a pin
or a box, for instance at a location between two axially separated threaded
zones of a pin or a
box. Examples of connections with torque shoulder surfaces between two axially
separated
threaded zones of a pin or a box are illustrated in U.S. Patent Publication
No.
U52010/0181763 to Mallis et al., incorporated herein by reference in its
entirety.
