Title of Invention

A PLASTICALLY RADIALLY EXPANSIBLE CONDUIT CONNECTION.

Abstract The present invention relates to a plastically radially expansible conduit connection, comprising: a first sealing surface disposed proximal to an end of a pin member of the connection; a second sealing surface disposed proximal to an end of a box member of the connection, the fIrst and the second sealing surfaces substantially opposite each other upon connection of the box member and pin member; a fIrst locking surface proximal to the sealing surface on the pin member; and a second locking surface proximal to the second sealing surface on the box member; wherein the first and second sealing surfaces and the first and second locking surfaces each having a diameter such that prior to plastic radial expansion of the box member and the pin member the locking surfaces are proximal to each other and do not contact each other, and after plastic radial expansion the fIrst and the second sealing surfaces develop a contact pressure, and the fIrst and second locking surfaces are engaged.
Full Text

Non-Rotating Expandable Connection with Collapsing Type Seal
Cross-reference to related applications
j This application is a continuation-in-part of U.S, Patent Application Serial
No. 09/457,997, filed on December 9, 1999. That application is incorporated by
reference in its entirety.
Background of Invention
Field of the Invention
The invention is related to threaded tubular joints usable in oil and gas will drilling and production, such as tubing, casing, line pipe, and drill pipe, commonly known collectively as oilfield tubular goods. More particularly, the invention relates to a seal for tubular joints for connecting male (pin) and female
(box) members.
Background Art
Threaded tubular connections are used for joining segments of conduits end-to-end to form a continuous conduit for transporting fluid under pressure. Oilfield tubular goods generally use such threaded connections for connecting
adjacent sections of conduit or pipe. Examples of such threaded end conner.tions
designed for use on oilfield tubular goods are disclosed in U,S. Patent Nqs. 2,239,942; 2,992,019; 3,359,013; RE 30,647; and RE 34,467, all of which are assigned to the assignee of this invention.
In U.S. Patent No, RE 30,647 issued to Blose, a particular thread from or structure is disclosed for a tubular connection that provides an unsually strong

joint while controlling the stress and strain in connected "pm' (male thread) and "box" (female thread) members to within acceptable levels. The pin member has at least one generally dovetail-shaped external thread whose width increases in one direction along the pin, while the box member has at least one matching generally dovetail-shaped internal thread whose width increases in the other direction. The mating set of helical threads provide a wedge-like engagement of opposing pin and box thread flanks that limit the extent of relative rotation between the pin and box members, and define a forcible make-up condition that completes the connection. In this thread structure, the angles of the flank shoulder, as well as the thread width, can be used to control the stress and strain preload conditions induced in the pin and box members for a given make-up torque. Thus, by tailoring the thread structure to a particular application or use, the tubular connection or joint is limited only by the properties of the materials selected- As shown in Figure 1, a prior art tubular connection 10 includes a pin member 11 and a box member 12. Box member 12 has a tapered, internal, generally dovetail-haped thread structure 14 formed thereon which is adapted for engaging complementary tapered, external, generally dovetail-shaped thread
structure 15 formed on pin member 11 to mechanically secure the box 12 and pin
11 members in a releasabic manner.
Internal thread 14 on the box member 12 has stab flanks 18, load flaks jl6, roots 20, and crests 24, The thread 14 increases in width progressively at a uniform rate in one direction over substantially the entire helical length 14. External thread 15 of pin member 11 has stab flanks 19, load flanks 17, roots 21, and crests 25. The thread 15 increases in width progressively at a uniform rate in the other direction over substantially the entire helical length of thread' 15. The oppositely increasing thread widths and the taper of threads 14 and 15, cause the complementary roots and crests of the respective threads 14 and 15 to move

into engagement during make-up of the connection 10 in conjunction with the
moving of complementary stab and load flanks into engagement upon make-up
of the connection.
The pin member 11 or the box member 12 defines the longitudinal axis 13
of the made-up connection 10. The roots and crests of the box and pin menbers
are flat and parallel to the longitudinal axis of the connection and have suff cient width to prevent any permanent deformation of the threads when the connection is made up.
An important part of any connection is a seal for keeping the conduit fluid pressure-tight at the connections. Typically connections will be designed to include metal-to-ractal seals therein. Metal-to-metal seals have the advantage pf not requiring gaskets or other additional sealing devices, which would typically have to be replaced periodically as the connections are coupled and uncoupled. Metal seals are created when contact pressure between two metal surfaces exceeds the fluid pressure to be scaled, Typically the contact pressursts are created during make up of the connection. More recently, oilfield tubular goods have been developed which can be plastically radially expanded from their initial diamexers after being installed for the intended application. See for example, R. D. Mack et al. How in situ Expansion Affects Casing and Tubing Properties, World Oil, July 1999, Gulf
Publishing Co., Houston, TX, for a description of plastically radially expanding
oilfield tubular goods. This article is mcorporated by reference in its entirety, |In
particular, this article discaisses the use of plastically radially expandable tabular
goods. Plastically radially expandable tubular goods have particular applicatipn
as casing in oil and gas producing wells. It has been difficult to seal piasticajly
radially expandable tubular connections using metal-to-metal seals known in the
art.

Summary of Invention

The invention is a plastically radially expansible conduit connccticn or
coupling. The connection includes a first sealing surface disposed proximal lo ah
end of a pin member of the connection, and it includes a corresponding second
sealing surface disposed proximal to an end of a box member of the connection.
The first and said second sealing surfaces are substantially opposite each other
upon connection of the pin and box members. The connection also includes a
first locking surface proximal to the sealing surface on the pin member end a
second locking surface proximal to the second sealing surface on the box
member. The first and second sealing surfaces and the first and second locking
surfaces each having a diameter such that prior to plastic radial expansion cf the
box member and the pin member the locking surfaces are proximal to each other
and do not contact each other, and after plastic radial expansion the first and the
second sealing surfaces develop a contact pressure, and the first and second
locking surfaces are engaged.
ief Description of Drawings
Figure 1 shows a prior art tubular threaded connection.
Figure 2 shows one embodiment of a connection seal of the invention prior to plastic radial expansion of the tubular joints and connection,
Figure 3 shows one embodiment of a connection seal of the invention after plastic radial expansion of the tubular joints and connection.
Figure 4 shows one embodiment of a connection of the invention that is
being plastically radially expanded.
Figure 5 shows one embodiment of a casing string that is being plastically radially expanded.

Figure 6A shows a top view cross-section of one embodiment of clearance
surfaces of the invention prior to plastic radial expansion.
Figure 6B shows a top view cross-section of one embodiment of clearance
surfaces of the invention after plastic radial expansion.
Figure 7A shows one embodiment of clearance surfaces of the invention
prior to plastic radial expansion
Figure 7B shows one embodiment of clearance surfaces of the invention after plastic radial expansion, Figure 8 shows one embodiment of clearance surfaces of the invention after plastic radial expansion.
Detailed Description
Figure 2 shows one example of a tubular connection 10A as used on plastically radially expandable tubular goods. The example shown in Figure 2lis for a threaded coupling. Figure 2 is a cross-section through only one side of the threaded tubular connection 10A, and the view shown in Figure 2 should therefore be thought of as rotationally symmetric about the axis (not shov/n) of the tubular connection 10A. The tubular connection 10A is formed by joining a male-threaded "pin" member 30 to a female-threaded "box" member 32, T le pin 30 and box 32 members have thereon corresponding threads 36 and 34, respectively, which when engaged provide axial coupling force to join txbujar joints together. The threads 34, 36 can be any type known in the art for coupling together tubular goods, and may be a seating type or a non-sealing type The particular type of threads selected will depend, as is known in the art, on the intended use of the tubular goods being joined by the connection 10A. The type of threads is not intended to limit the invention. It should also be noted that the connection 10A can be formed wherein segments of conduit (not shown



diameters on the pin surfaces 42, 44 which provides larger clearance between corresponding clearance surfaces 38,42 will also work with the invention,
Although Figure 2 shows the sealing surfaces 40, 44 as having a small amount of clearance between them prior to radial expansion of the pin 30 and box 32, the sealing surfaces 40, 44 may also be in interference contact with each other. Where the sealing surfaces 40, 44 are in interference contact pr or to plastically radial expansion, after radial expansion the sealing surfaces 40, 44 will contact each other at a higher contact pressure than prior to expansion as
long as the clearance surfaces 38,42 remain out of contact after expansion,

The amount of clearance between the clearance surfaces 38, 42 prior to
plastically radial expansion will depend on, among other factors, the amount pf
radial expansion to be applied to the pin 30 and box 32 and the pre-expansion
diameter of the pin 30 and box 32. Generally, large clearance where the amount
of expansion is small, or small clearance where the amount of expansion is to be
large are not highly desirable. A preferred amount of clearance between the
sealing surfaces is about 30 to 40 percent of the amount of plastic expansion to
be applied, although other clearances will work with the invention, including an
interference fit, as previously explained, A preferred pre-expansion clearance for
the clearance surfaces is about 50 to 55 percent of the amount of plastic radial
expansion, although other clearances will work with the invention. The
important aspect is that the clearance surfaces 38, 42 retain some clearance
therebetween after radial expansion of the box 32 and pin 30.
Figure 3 shows the connection 10A after plastic radial expansion of the pin 30 and box 32. As can be seen in Figure 3, the sealing surfaces 40, 44 have been
put into sealing contact with each other by reason of the plastic radial expansion of the pin 30 and box 32. The clearance surfaces 38, 42 do not come into contact

with each other as a result of the plastic radial expansion of the pin 30 and box
,
While the embodiment of the invention described herein includes ,a
threaded coupling for joining segments of conduit, the invention does not require

the use of threaded couplings. For example, J-slot connectors including locking pins on the pin end, with corresponding slots on the box end could provide axial coupling force to hold the pin and box together. Other types of couplings which do not use mating threads can also be devised by those skilled in the art.
In general, there are two primary types of methods for plastically radially
expanding tubular goods. The first is a '"cone" or "pig" type expansion, and the
second is a "rotary' type expansion,
"Cone" or "pig" type expansion includes using a forming the that is removed through a tubular member in an axial direction. The forming die is larger than the inside diameter of the tubular member, and the forming die causes the tibular member to plastically radially expand as the die moves through the tibular member.
"Rotary" type expansion methods use a forming die that includes rotatable rollers. A rotary type die is also larger than the inside diameter of the tubular member, and it is rotated as it is forced through the tubular member in an axial direction. The combination of axial and torsional forces causes to member to plastically radially expand as the die moves through the tubuliar member.
With rotary expansion, the forming die typically is rotated "to the right," which means in a clockwise direction looking down the hole. Right-moulded rotation is the standard direction for oilfield drillstrings. During -rotary expansion, the right-hand rotation of the forming die will tend to loosen, or "break-out," right-handed threads in the tubular connections, such as well casing.


When the roller 403 moves axially into contact with the inside diameter of the box member 416, the rotation of the roller 403 along with the reduced preload in the connection may cause the box member 416 to rotate with respect to the pin member 415. In a right-handed connection, the right-handed rotation of the roller 403 would cause the box member 416 to unscrew, or "back off." In a left-handed connection, the rotation of the roller 403 would cause the box member 416 to screw together, or "make-up/'

Connections in a casing string that have already been plastically radially expanded also may be susceptible to relative rotation. The gaps created between the threads during the expansion process, along with the rotation of the rolier as it moves away from an expanded connection, may cause undesirable relative rotation in connections after the expansion process.
Figure 5 shows a roller 501 that is being run downward through a casing
string 511 in a borehole. A drillstring 502 is used to rotate the roller 50J in a
right-handed direction (shown by arrow 504). Figure 5 shows the roller as a lower connection 514 is expanded.
As described above, an upper connection 512 that has been previously expanded by the roller 501 also may experience relative rotation between the pin and box member of that connection 512, In particular, this may occur when the casing 511 is trapped by an obstruction 522 in the formation that prevents the free rotation of the casing string 51L In contrast to the above, where . left-handed threaded connection that is being presently expanded will make-up due to the right-hand rotation of a roller, a previously expanded left-handed threaded
connection will tend to back-off due to the rotation of the roller. Thus, in this

embodiment, if the upper connection 512 is a left-handed connection, the rotation of the roller 501 will cause the upper connection to back-off. On the other hand, if the upper connection 512 is a right-handed connection, the rotation of the roller 501 will cause the upper connection 512 to make-up.
Figure 5 shows a roller 501 that moves downward through a casing string

51L Those havhig ordinary skill in the an will realize that the roller 5)1, In certain embodiments, could move upward through the casing string 51L In that case, a lower connection may experience relative rotation as the roller 501 moves upward through the casing string 511 and upper connections. No limitation is intended by a description of the direction of roller movement.

Figure 6A shows one embodiment of an anti-rotation device 6(!) in accordance with an embodiment of the invention. Figure 6A shows a cross-
section taken through section A-A in Figure 7A. The box member 611 and the
j
pin member 621 arc shown prior to plastic radial expansion. The box member
611 has a locking surface 613. In the embodiment shown, the box member
locking surface 613 is knurled so that it includes peaks 617 and grooves 615.
The pin member 621 also includes a loading surface 613. The pin member
locking surface 623 is similarly knurled to include corresponding peaks 625 and
grooves 627.
Prior to expansion, the peaks 625 on the pin member locking surface 623 and the peaks 617 on the box member locking surface 613 have diameters selected such that they will not contact each other. This enables the pin member
612 and the box member 611 to rotate with respect to each other during for
example, initial make-up of the connection.
Figure 6B shows one embodiment of an anti-rotation device 601 after plastic radial expansion. The peaks 625 and grooves 627 of the pin member locking surface 623 engage with corresponding peaks 617 and grooves 615 of the box member locking surface 613. This engagement prevents relative rotation between the pin member 621 and the box member 611, It is noted that in some embodiments, such as the one shown in Figure 68, although the peaks 625 and grooves 627 of the pin member locking surface 623 are 'engaged" with corresponding peaks 617 and grooves 615 of the box member locking surface 613, the pin member locking surface 623 is not in contact with the box member locking surface 613. If the box member 611 were to be rotated, it would cause rotational contact between the peaks 617, 625 of the locking surfaces 613, 623. The contact between the peaks 625 of the pin member locking surface 623 and the peaks 617 of the box member locking surface 613 would prevent relative rotation. Such contact would be caused by relative rotation of the pin member

621 and the box member 611 and not by the radial expansion of the connection.
In some other embodiments, there is contact between the locking surfaces 613,
623 after plastic radial expansion.
Figure 7A shows a cross-section of a connection 700 with a collapsible seal 701 and an anti-rotation device 702 prior to plastic radial expansion. The pin member 730 includes a first sealing surface 740 and a first clearance surface 738. The pin member also includes a first locking surface 711 disposed proximal the first sealing surface and the first clearance surface. The first locking surface 711 is knurled, and the section shown in Figure 7A includes a groove. Likewise:, the box member 732 has a second sealing surface 744 and a second clearance surface 742. A second locking surface 721 is disposed proximal to the second sealing surface 744 and the second clearance surface 742. The second locking surface 721 is also knurled, and the section shown in Figure 7A includes a peak.
It is notes that the knurled locking surfaces 711, 721 each contain peaks and grooves. In the embodiment shown in Figxire 7A, the cross-section is taken at la point where there is a groove in the first locking surface 711 and a peak i i the second locking surface 721. A cross-section at a different point may show a peak in the first locking surface and a groove in the second locking surface. j
Figure 7B shows a cross-section of an embodiment a connection 700 after plastic radial expansion of the pin member 730 and the box member 732. As was discussed above with reference to Figure 3, the second sealing surface 744 on the box member 732 has collapsed to be in sealing contact with the first sealing surface 740 on the pin member 730. In the embodiment shown, the clearance surfaces 738, 742 remain out of contact.
Figure 7B shows that the first locking surface 711 in engaged with the second locking surface 721. Because the locking surfaces 711, 721, it the embodiment shown, have an alternating peak/groove pattern, the engagement

between them prevents relative rotation between the pin member 730 and the box member 732,
In other embodiments, an anti-rotation device may comprise flutes on the locking surfaces or high friction coatings en the locking surfaces, such as a plasma-spray carbide. Those having ordinary skill in the art -will realize that anti-rotation devices other than a knurled surface may be used without departing from the scope of the invention.
In some embodiments the locking surfaces may include coatings that are in contact after plastic radial expansion. Figure 8, for example, shows a cross-section of an embodiment of a threaded connection 800 with a collapsible: type seal 801 and locking surfaces 811, 821 with coatings 851, 852 that contact. each other after plastic radial expansion. A first sealing surface 840 is in sealing contact with a second sealing surface 844, and the first clearance surface 8:8 and the second clearance surface 842 remain out of contact The first coating 852 on the first locking surface 811 and the second coating 851 on the second kicking surface 821 are in contaci with each other. In some embodiments, the catings 851, 852 are high friction coatings that resist relative rotation between the pin member 830 and the box member 832.
Those having ordinary skill in the art will be able to devise other embodiments of locking surfaces and anti-rotation devices that do not depart from the scope of the present invention. For example. In some embodiments, a connection with a anti-rotation device does not include clearance surfaces. While the embodiments shown include clearance surfaces, those having ordinary
sill in the art will realize the they are not required by the present invention.
Advantageously, embodiments of the present invention that include so anti-rotation device enable the plastic radial expansion of tubular goods using rotary expansion techniques without relative rotation between the pin member and the

box member. Further, certain embodiments prevent the relative rotation of
previously expanded connections by the rotation of a rotary expansion tool, such
as a roller.
While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims.


Claims
What is claimed is:
[c1] A plastically radially expansible conduit connection, comprising:
a first sealing surface disposed proximal to an end of a pin member of the
connection;
a second sealing surface disposed proximal to an end of a box member of the

connection the first and the second sealing surfaces substantially opposite
each other upon connection of the box member and pin member;
a first locking surface proximal to the sealing surface on the pin member; and
a second Socking surface proximal to the second sealing surface on the box
member:
wherein the first and second sealing surfaces and the first and second looking

surfaces each having a diameter such that prior to plastic radial expanse
of the box member and the pin member the locking surfaces are proximal to each other and do not contact each other, and after plastic radial expansion the first and the second sealing surfaces develop a contact pressure, and the
first and second locking surfaces are engaged.
[d] The plastically radially expansible conduit connection of claim 1, further comprising a first clearance surface disposed on the pin member between the first scaling surface and the first locking surface, and a second clearance surfaces disposed on the box member between the second sealing surface and the second locking surface, wherein the first and second clearance surfaces each have a diameter such that prior to plastic radial expansion of the pin member and the box member the first and second clearance surfaces do not contact each other, and after
plastic radial expansion of the pin member and the box member the first and

second clearance surfaces remain out of contact,

.[c3] The plastically radially expansible conduct connection of claim 1, wherein at least one of the first locking surface and the second locking surface comprises a
surface.
[c4] The plastically radially expansible conduit connection of claim 1, wherein at least one of the first locking surface and the second locking surface comprises flutes.
[c5] The plastically radially cxpansible conduit connection of claim 1, further comprising a coating disposed on one of the first locking surface and the second locking surface, and wherein after plastic radial expanion of the pin member arid
the box member the coating contacts the other of the first locking surface and the
second locking surface.
[c6] The plastically radially expansible conduit connection of claim 1, further comprising a first coating disposed on the first locking surface and a second coating disposed on the second locking surface, and wherein after plastic radial expansion of the pin member and the box member the first coating and the second coating are in contact.
[c7] The plastically radially expansible conduit connection of claim 6, wherein the first coating and the second coating comprise a high friction coating.

8. A plastically radially expansible conduit connection substantially as herein described with reference to the accompanying drawings.


Documents:

307-che-2004-abstract.pdf

307-che-2004-claims dublicate.pdf

307-che-2004-claims original.pdf

307-che-2004-correspondnece-others.pdf

307-che-2004-correspondnece-po.pdf

307-che-2004-description(complete) dublicate.pdf

307-che-2004-description(complete) original.pdf

307-che-2004-drawings.pdf

307-che-2004-form 1.pdf

307-che-2004-form 19.pdf

307-che-2004-form 26.pdf

307-che-2004-form 3.pdf

307-che-2004-form 5.pdf


Patent Number 204417
Indian Patent Application Number 307/CHE/2004
PG Journal Number 26/2007
Publication Date 29-Jun-2007
Grant Date 21-Feb-2007
Date of Filing 01-Apr-2004
Name of Patentee M/S. HYDRIL COMPANY
Applicant Address 3300 NORTH SAM HOUSTON PARKWAY, EAST HOUSTON, TEXAS 77032
Inventors:
# Inventor's Name Inventor's Address
1 ROBERT A.SIVLEY, 4806 ECHO FAILS DR., KINGWOOD, TEXAS 77345
2 JOHN F. GREENIP, 7738 CANDLEGREEN, HOUSTON, TEXAS 0,
3 HARRIS A. REYNOLDS JR., 1 706 CRANWAY, HOUSTON, TEXAS 77055,
PCT International Classification Number F 16 L 21/02
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10/404,800 2003-04-01 U.S.A.