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Publication numberUSRE34467 E
Publication typeGrant
Application numberUS 07/869,812
Publication dateDec 7, 1993
Filing dateApr 16, 1992
Priority dateApr 29, 1983
Fee statusPaid
Publication number07869812, 869812, US RE34467 E, US RE34467E, US-E-RE34467, USRE34467 E, USRE34467E
InventorsDoyle E. Reeves
Original AssigneeThe Hydril Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Tubular connection
US RE34467 E
Abstract
An improved threaded connection adapted to secure adjacent conduits in a continuous flow conduit forming relationship. The threaded connection employs a tapered or wedge shaped thread with angled or tapered thread load flanks to obtain superior mechanical strength by controlling stress levels in the connection. To insure proper make-up of the connection the dimension of the thread structure is controlled to prevent trapping of thread lubricant during rotational make-up which may produce false torque make-up values.
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Claims(10)
What is claimed is:
1. A threaded pipe connection comprising a box having tapered, internal, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe and a pin having tapered, .[.exteranl.]. .Iadd.external.Iaddend., generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe for mating with the internal threads of the box to make up a pipe connection, a pipe thread lubricant coating the threads, said threads increasing in width in one direction on the box and in the other direction on the pin so the roots, crests, and flanks of the threads move together and form seals that resist the flow of fluids between the threads with .[.the stab flanks and.]. the roots and crests being designed to move into .[.sealing.]. engagement before both the load flanks and the stab flanks move into .[.sealing.]. engagement .[.after which the flanks will move together and form seals.]. to complete the sealing of the connection as the connection is fully made up.
2. A threaded pipe connection comprising a box having tapered, internal, generally dovetail-shaped threads and a pin having tapered, external, generally dovetail-shaped threads that mate with the threads on the box when the connection is made up, a pipe thread lubricant coating the threads, said threads on the box and pin having stab flanks that are in engagement as the pin moves into the box due to relative rotation of the pin and box, roots and crests that move into engagement .[.when the connection is made up hand-tight.]. .Iadd.during rotational make-up.Iaddend., and load flanks that move into engagement .[.when the connection is fully made up.]. .Iadd.upon rotational make-up of the threaded connection.Iaddend..
3. A threaded pipe connection comprising a box having tapered, internal, generally dovetail-shaped threads with stab flanks and load flanks, and flat roots and crests that are parallel to the longitudinal axis of the pipe, and a pin having tapered, external, generally dovetail-shaped threads with stab flanks and load flanks, and flat roots and .[.rests.]. .Iadd.crests .Iaddend.that are parallel to the longitudinal axis of the pipe, for mating with the internal threads of the box .[.tomade.]. .Iadd.to make .Iaddend.up a threaded pipe connection, said threads increasing in width in one direction on the box and in the other direction on the pin so that .[.the stab flanks.]., the roots and crests .Iadd.move into engagement during rotational makeup .Iaddend.and the .[.load.]. flanks of the threads .[.mave.]. .Iadd.move .Iaddend.together .[.sequentially as.]. .Iadd.when .Iaddend.the connection is .Iadd.fully .Iaddend.made up, said roots and crests having sufficient width to prevent any permanent deformation of the threads .[.adjacent the roots and crests when the connection is made up.]..
4. In a threaded pipe connection including a box having tapered, internal, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe and a pin having tapered, external, generally dove-tail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe for mating with the internal threads of the box to make up a threaded pipe connection, said threads increasing in width in one direction on the box and in the other direction on the pin, and with at least the threads on one of the box and pin being coated with thread lubricant prior to make up the improvement to prevent the trapping of thread lubricant between the roots and crests causing an indication that the connector is made up before it is .[.,the improvement.]. comprising .[.,.]. the stab flanks and the roots and crests being designed to move into engagement when the pin and box are made up hand-tight .Iadd.during rotational make-up of the connection .Iaddend.after which continued make up of the connection moves .[.the stab flanks, the roots and crests, and.]. the load flanks into .[.sealing.]. engagement .[.when.]. .Iadd.upon rotational make-up of .Iaddend.the connection .[.is fully made up.].. .[.5. In a threaded pipe connection comprising a box having tapered, internal, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe and a pin having tapered, external, generally dove-tail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe for mating with the internal threads of the box to make up a threaded pipe connection, a pipe thread lubricant coating the threads, said threads increasing in width in one direction on the box and in the other direction on the pin the improvement comprising having the roots, crests, and flanks of the threads move together and form seals with the stab flanks moving together as the connection is being made up and the roots and crests being designed to move together when the pin and box are made up hand-tight after which continued make up of the connection moves the load flanks together completing the final make up of the connection thereby reducing substantially the volume of lubricant between
the roots and crests when the connection is made up.].. 6. A threaded pipe connection comprising a box having tapered, internal, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe and a pin having tapered, external, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe for mating with the internal threads of the box to make up a pipe joint, a pipe thread lubricant coating the threads, said threads increasing in width in one direction on the box and in the other direction on the pin so the roots, crests, and flanks of the threads move together and form seals that resist the flow of fluids between the threads with .[.the stab flanks and.]. the roots and crests being designed to move into .[.sealing.]. engagement before both the load flanks and the stab flanks move into .[.sealing.]. engagement .[.after which the flanks will move together and form seals.]. to complete the sealing of the
connection as the connection is fully made up. 7. A threaded pipe connection comprising a box having tapered, internal, generally dovetail-shaped threads and a pin having tapered, external, generally dovetail-shaped threads that mate with the threads on the box when the connection is made up, a pipe thread lubricant coating the threads, said threads on the box and pin having stab flanks that are in engagement as the pin moves into the box due to relative rotation of the pin and box, roots and crests that move into engagement when the connection is made up hand-tight, and load flanks that move into engagement when the connection is fully made up, said roots and crests being flat wide surfaces so that, when engaged, the stress induced in the threads adjacent the .[.matin9.]. .Iadd.mating .Iaddend.surfaces does not exceed the yield of the thread material. .Iadd.8. A threaded pipe connection comprising a box having tapered, internal, generally dovetail-shaped threads and a pin having tapered, external, generally dovetail-shaped threads that mate with the threads on the box when the connection is made up, a pipe thread lubricant coating the threads, said threads on the box and pin having stab flanks that are in engagement initially as the pin moves into the box and roots and crests that move into engagement after the stab flanks but before the load flanks move into engagement when the connection is fully made up.
.Iaddend. .Iadd.9. In a threaded pipe connection including a box having tapered, internal, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe and a pin having tapered, external, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe for mating with the internal threads of the box to make up a threaded pipe connection, said threads increasing the width in one direction on the box and in the other direction on the pin, and with at least the threads on one of the box and pin being coated with thread lubricant prior to make up, the improvement to prevent the trapping of thread lubricant between the roots and crests causing an indication that the connector is made up before it is, the improvement comprising, the roots and crests being designed to move into engagement before both the stab flanks and the load flanks move into engagement as the connection is fully made up. .Iaddend. .Iadd.10. In a threaded pipe connection comprising a box having tapered, internal, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe and a pin having tapered, external, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe for mating with the internal threads of the box to make up a threaded pipe connection, a pipe thread lubricant coating the threads, said threads increasing in width in one direction on the box and in the other direction on the pin the improvement comprising having the stab flanks and load flanks, but not both, in engagement at any one time before the roots and crests move into engagement during rotational make-up of the connection after which the other flanks move into engagement upon rotational make-up of the connection. .Iaddend. .Iadd.11. A threaded pipe connection comprising a box having tapered, internal, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe and a pin having tapered, external, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe for mating with the internal threads of the box to make up a pipe connection, a pipe thread lubricant coating the threads, said threads increasing in width in one direction on the box and in the other direction on the pin so the roots, crests, and flanks of the threads move together and form seals that resist the flow of fluids between the threads with the roots and crests being designed to move into engagement during rotational make-up before both the load flanks and the stab flanks move into engagement when the connection is fully made up.
.Iaddend. .Iadd.12. A threaded pipe connection comprising a box having tapered, internal, generally dovetail-shaped threads and a pin having tapered, external, generally dovetail-shaped threads that mate with the threads on the box when the connection is made up, a pipe thread lubricant coating the threads, said dovetail-shaped threads on the box and pin providing stab flanks and load flanks only one set of which is in engagement at any given time as the pin moves into the box during rotational make-up of the pin and box and roots and crests that move into engagement during rotational make-up before the other set of flanks move into engagement upon rotational make-up of the connection. .Iaddend.
.Iadd.3. A threaded pipe connection comprising a box having tapered, internal, generally dovetail-shaped threads with stab flanks and load flanks, and flat roots and crests that are parallel to the longitudinal axis of the pipe, and a pin having tapered, external, generally dovetail-shaped threads with stab flanks and load flanks, and flat roots and crests that are parallel to the longitudinal axis of the pipe, for mating with the internal threads of the box to make up a threaded pipe connection, a pipe thread lubricant coating the threads, said threads increasing in width in one direction on the box and in the other direction on the pin whereupon during rotational make up one or the other of the flanks, but not both may be in engagement at any given time prior to engagement of the roots and crests during rotational make-up and the remaining unengaged flanks of the threads moving together after the engagement of the roots and crests upon rotational make-up of the
connection. .Iaddend. .Iadd.14. In a threaded pipe connection comprising a box having tapered, internal, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe and a pin having tapered, external, generally dovetail-shaped threads with stab flanks and load flanks and flat roots and crests that are parallel to the longitudinal axis of the pipe for mating with the internal threads of the box to make up a threaded pipe connection, a pipe thread lubricating coating the threads, said threads increasing in width in one direction on the box and in the other direction on the pin the improvement comprising having the roots, crests, and one of the flanks of the threads move together when the pin and box are made up hand-tight during rotational make-up of the connection after which continued rotational make-up of the connection moves the other flanks together upon rotational make-up of the connection thereby reducing substantially the volume of a lubricant between the roots and crests when the connection is made up. .Iaddend.
Description
BACKGROUND OF THE INVENTION

1. Technical Field

The present invention, which is a continuation of application Ser. No. 868,887, filed May 27, 1986, entitled "IMPROVED TUBULAR CONNECTION", which is a continuation of Ser. No. 489,739, filed Apr. 29, 1983, .Iadd.both .Iaddend.now abandoned, entitled "TUBULAR CONNECTION", relates generally to the field of tubular connections and more specifically to the field of threaded connections for securing flow conduits to form a desired continuous flow path.

2. Background Art

The use of threaded connections for joining flow conduits in an end-to-end relationship to form a continuous flow path or channel for transporting fluid under pressure is well known. The use of threaded connections in the production of hydrocarbons and other forms of energy from subsurface earth formations is particularly well known. Drill pipe, well casing and production tubing, commonly known collectively as oilfield tubular goods, all utilize threaded connections for connecting adjacent conduit sections or pipe joints. Examples of such threaded end connections for use on oilfield tubular goods are disclosed in Stone et al. Pat. No. 2,239,942; MacArthur Pat. No. 2,992,019; and Knox et al. Pat. No. 3,359,013, which were all assigned to the assignee of the present invention.

In Blose Pat. No. RE 30,647, also assigned to the assignee of the present invention, there is disclosed a tubular connection having a unique thread form or structure that provides an unusually strong connection while controlling the stress and strain in the connected pin and box members within acceptable levels. The mating helical threads are tapered in thread width in opposite directions to provide a substantially simultaneous wedge-like engagement of the opposing flanks to limit rotational make-up of the connection. The value of the thread width as well as the value of the flank shoulder angles are two of the variables that may be used to control the stress and strain induced in the pin and box for a given make-up torque.

When making up a threaded connection manufactured in accordance with the disclosure of the Blose reissue patent, liquid and paste-like thread lubricants have been temporarily trapped in the helical clearance between the roots and crests of the threads. The trapped fluid may, under certain circumstances give a false indication that the connection is properly made up. Thereafter, the temporarily trapped thread lubricant or thread dope can bleed off through the helical clearance between the roots and crests reducing the preload stress and strain so that the anticipated performance level or strength of the threaded connection may not be achieved. While such reduction in the performance level is not properly attributable to a deficiency in the connection or its design, the consequence of improper make-up is an unacceptable performance level for the threaded connection.

SUMMARY OF THE INVENTION

The present invention relates to an improvement for a thread structure to increase the probability or likelihood of proper make-up of the threaded connection. When properly made up a thread structure having a tapered thread width and one or more dove-tail flanks exhibits superior mechanical strength. By tailoring the thread structure to a particular application or use, the threaded connection is limited only by the properties of the materials of construction used in making the connection. To achieve such a level of performance it is necessary to forceably make-up the connection to a predetermined torque value to insure that the design stress and strain preload conditions actually exist in the connection.

Frequently, oilfield tubular goods must be assembled or made up under extremely adverse conditions. In addition, the threaded connections may experience deterioration or damage in handling and transportation to the well site where they are to be used. In addition to these general factors, the particular thread structure disclosed in Blose Pat. No. RE 30,647 has exhibited some tendency to trap liquid or paste-like thread lubricants in the radial clearance areas between the thread roots and crests and prevent the desired normal force to be developed between the thread flanks even though the proper torque is applied to the connection. Unless the connection is properly tightened to a described level, the performance of the threaded connection will be significantly reduced. While the lubricant can and will be extruded from the trapping areas if the torque is maintained on the connection for a sufficient period of time, the personnel running or installing the oilfield conduits cannot be certain that torquing had been properly accomplished.

The present invention reduces the volume of trapped thread lubricant and locates most of the trapped lubricant in the helical space between the load flanks that has a very small axial thickness and little or no effect on the proper make-up of the connection or the ability of the thread surfaces to form seals as thy move together.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view, in section, of the prior art thread structure;

FIG. 2 is a side view, in section, of a prior art connection having the prior art thread structure;

FIG. 3 is a side view, partially in section, of a pin member having the thread structure of the present invention formed thereon;

FIG. 4 is a side view, partially in section, of a threaded and coupled connection of the present invention;

FIG. 5 is a side view, in section, of a tubular conduit having an external pin thread structure of the present invention formed thereon;

FIG. 6 is a partial side view, in section, of a coupling having another form of the thread structure of the present invention formed internally thereon; and

FIG. 7 is a cross-sectional view on an enlarged scale of a pin and box having the dove-tail shaped threads used with the preferrerd embodiment of the invention.

BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENT

The prior art FIGS. (Nos. 1 and 2), correspond to FIGS. 2 and 6, respectively of Blose U.S. Pat. No. RE 30,647. That patent, along with all of the other patents mentioned or identified herein are incorporated by reference as if actually set forth herein. However, for background purposes in understanding the present invention a brief description of the Blose prior art construction is set forth hereinbelow.

The Blose threaded connection or pipe joint, generally designated 10, includes a first or pin member 11 and a second or box member 12, respectively, with either one or both of the members defining the longitudinal axis 13 of the made-up connection 10. As illustrated in FIG. 2, the box member 12 has an internal thread structure 14 formed thereon adapted to engage a complementary external thread structure 15 formed on the pin 11 for mechanically securing in a releasable manner the members 11 and 12. Helical threads 14 and 15 have a dove-tail interfit so that a first load flank wall 16 of the thread 14 engages with complementary load flank wall 17 formed on the thread 15. The opposite or stab flank wall 18 formed by the thread structure 14 engages the complementary stab flank wall 19 formed by the thread structure 15. As used herein, and as conventionally understood where pipe joints are being connected in a vertical position, such as when making up a pipe string for lowering into a well bore, the term "load flank" designates that side wall surface of a thread that faces away from the outer end of the respective male or female member on which the thread is formed, and the term "stab flank" designates that side wall surface that faces toward the outer end of the respective male or female member and supports the weight of the joint during the initial make up of the joint.

An angle α is formed between the flank wall 18 and the root wall 20 of the thread 14. Likewise, the angle α is also formed between the stab flank wall 19 and the root wall 21 of the thread structure 15. The flank wall 16 and the root wall 20 as well as the flank wall 17 and the root wall 21 of the thread 15 form a second angle β. The angles α and β are preferably acute angles to provide dovetail shaped threads. However, it should be understood that a semi-dovetail form can be provided where one of the angles α and β can be ninety (90) degrees which would flank wall perpendicular or normal to the longitudinal axis 13 of the connection. In the disclosure of the Blose reissue Pat No. 30,647, clearances 22 and 23 are provided between the root walls 20 and 21 and the thread crests 24 and 25 of the threads 14 and 15, respectively in the hand tight position so that relatively wide helical spaces containing thread lubricant are present throughout the length of the threads. As will be noted in FIG. 2, the helical thread 14 formed on the first or box member 12 has a greater thread width between the flanks 16 and 18 at the thread tip or crest 24 than at the base of the thread; likewise, helical thread 15 has a greater axial distance between flanks 17 and 19 at the thread crest 25 than at the base of the thread. Further, each thread 14 and 15 has a progressively reducing thread width in opposite directions along the helical length thereof to provide a tapered wedge thread arranged such that flanks 16 and 18 of thread 14 engage load flanks 17 and 19 of thread 15 at substantially the same time when the threads are made up hand tight. Prior to that time, there is a gap between at least one of the flanks of threads 14 and 15. In the embodiment illustrated from the Blose reissue patent, the maximum thread width of the tapered thread is no greater than twice the thread width at the narrowest point for a corresponding location on a flank.

The connection 10 illustrated in FIG. 2 is provided with a multiple or two step cylindrical thread having a stop shoulder 30 formed on the pin member 11 that engages a corresponding stop shoulder 32 on the box 12. Because the engaging flanks of threads 14 and 15 also serve as a make-up stop shoulder, it may be desired to provide a clearance gap between the shoulders 30 and 32. The connection 10 is also provided with the conventional conical metal-to-metal seal zone on the pin 11 at 34. A companion sealing surface 36 formed on the box 12 engages the pin sealing surface 34 to block passage of fluid therebetween. In the illustrated embodiment of FIG. 2 a plastic seal ring 38 such as disclosed in U.S. Pat. No. 3,100,656 to MacArthur, may be employed. Such plastic ring 38 is preferably used with internally lined pipe for providing a continuous corrosion-resistant surface.

In the embodiment illustrated in FIG. 2, the threads are formed at a common radial distance or radius from the longitudinal axis 13 of the joint to provide a cylindrical rather than a tapered thread. The thread structures 14 and 15 are formed on a larger radius while the second step threads, referenced as 14a and 15a, are formed on a small radius or distance from the longitudinal axis 13 of the connection 10. The two step thread, which may be cylindrical or tapered, is recognized for its speed of assembly during installation operations as is known in the art.

In the embodiment of the present invention illustrated in FIG. 3 and in FIG. 7 like reference characters, increased by 100, have been used to designate like parts to simplify and shorten the written description. A pin member 111 is provided with external helical thread structure 115 on upset end portion 111a of pin 111. It is to be understood however that the thread structure of the present invention is equally well suited for non-upset or plain end pipe. The tapered wedge-like thread structure 115 also has one or both of its flank 117 and 119 inclined outwardly at an acute angle so as to provide a generally dove-tail shape. The thread root 121 separates the oppositely facing flank shoulders 117 and 119 which are disposed adjacent thereto. The thread crests 125 are disposed at the outer ends of the flanks 117 and 119 and alternate with the thread roots 121 in the conventional manner. The thread width between the oppositely facing flank surfaces 117 and 119 below the thread crests 125 varies progressively at a uniform rate substantially the entire helical length of the thread 115. This provides a tapered wedge thread design in which the flanks 117 and 119 engage the corresponding fanks on the threads of the female member at substantially the same time upon rotational make-up of the threaded connection. In viewing the lower portion of FIG. 3 it will be immediately appreciated that the axial thread width decreases or varies progressively at a much greater rate from that illustrated in the embodiment of FIG. 2. In particular, it has been found desirable to increase the axial thread width at the widest portion in the range of approximately four times the thread width at the narrowest portion. This contrasts with the embodiment illustrated in FIG. 2 where the thread width at the widest portion is only twice the thread width at the narrowest portion. The pin member 111 may be provided with an identical or different thread structure on the other end (not illustrated) in the conventional manner.

In the present invention, the thread roots 121 and the thread crests 125 on the pin are dimensioned to eliminate the formation of the radial clearance illustrated at 22 and 23 in FIG. 1 and FIG. 2. In other words, thread roots 121 and thread crests 125 come into interference contact with the corresponding surfaces of the box, i.e., when the joint is made up hand tight. By eliminating the radial clearance between the thread roots 120 and 121 and crests 124 and 125 with the complementary thread structure, the possibility of creating chambers therebetween upon hand tight connection make-up that can virtually entrap the liquid or paste-like thread lubricant theein and create high squeeze film pressures which produce false torque readings is greatly minimized if nsot entirely reduced. In order to achieve this result the roots 120 and 121 and crests 124 and 125 of the threads are dimensioned to be in contact with each other upon hand tight make up and may, if desired to be dimensioned to provide a radial interference for inducing a controlled stress in the pin member 111 upon forceable make-up.

The pin member 111 may also be provided with the conventional metal-to-metal seal area 111b for blocking leakage of fluid between the pin 111 and the box member when the connection is made up in the usual manner.

FIG. 4 illustrates the pin 111 of FIG. 3 made up in a box member or coupling 112 to form a thread and coupled (T & C) connection 110. The coupling 112 is provided with the internal or box complementary thread structure 114 for making up with the pin in the usual manner. When assembled in the manner illustrated the thread roots 120 and 121 coact with the thread crests 124 and 125 to prevent formation of undesired radial clearance that may traps thread lubricant during assembly in the manner described above.

The upper portion of the coupling 112 is illustrated with an identical thread structure facing in the opposite direction for connecting with a tube, pipe or conduit disposed adjacent to and above the coupling 112 in the usual manner. If desired a different thread structure may be provided in the upper portion of the coupling 112 without departing from the scope of the present invention.

In the embodiment of FIGS. 5 and 6, a two step conical or tapered (i.e., varying thread diameter) thread construction is illustrated rather than a cylindrical two step thread such as disclosed in FIG. 2. The pin 211 has an external helical thread structure 215 formed in accordance with the present invention while the coupling 212 is provided with two internal helical thread structures 214 facing in opposite directions for coupling with adjacent tubes in the conventional manner. In FIG. 6 it is again to be understood that a different thread profile or structure may be provided at one end of the coupling or box member 212. Disposed substantially equi-distant from the outer ends of the coupling 212 is an inwardly projecting collar 260 forming a downwardly facing annular shoulder 262 and an upwardly facing shoulder 264. Because the tapered or wedge configuration of the threads 214 and 215 provide stop shoulders to limit rotational make-up of the coupling 212 on the pin 211, the end surface 261 of pin 211 is not brought in contact with the downwardly facing shoulder 262 of the flange 260. However, the flange 260 serves to provide a substantially turbulent-free flow path to minimize the effects of flow erosion on the coupling 212.

The sealing area 240 of the coupling 212 is located intermediate of the two steps of tapered threads. The sealing area 240 of the coupling engages the seal area 242 formed on the pin 211 intermediate the two spaced thread steps to form an additional metal-to-metal seal to block leakage of fluid between the coupling 212 and the pin 211 in a conventional manner. While an intermediate seal is illustrated it should be understood that other seal locations and types of seal are equally well suited for use with the present invention.

The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made without departing from the spirit of the invention.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US412446 *Jan 5, 1889Oct 8, 1889 horace r
US671274 *Oct 19, 1900Apr 2, 1901William Charles FischerLocking device for parts of machinery.
US1474375 *Sep 10, 1920Nov 20, 1923Us GovernmentAir-flask joint
US1932427 *Jun 15, 1931Oct 31, 1933Doheny Stone Drill CoWell pipe joint
US2006520 *Jul 17, 1933Jul 2, 1935Hydril CoCasing joint
US2051499 *Jan 25, 1930Aug 18, 1936 Fife joint
US2062407 *Feb 19, 1935Dec 1, 1936Spang Chalfant & Company IncJoint
US2140467 *Dec 1, 1937Dec 13, 1938George E Failing Supply CompanThreaded joint
US2177100 *Sep 21, 1938Oct 24, 1939Nat Supply CoLeak-resisting pipe thread
US2183644 *Dec 27, 1938Dec 19, 1939 Threaded joint and apparatus for
US2196966 *Oct 24, 1939Apr 9, 1940Security Engineering Co IncWell pipe joint
US2206223 *Feb 26, 1938Jul 2, 1940Dearborn Joseph HerbertFastening means
US2207005 *Oct 18, 1938Jul 9, 1940Rawley D HaasPipe and tool joint
US2239942 *May 17, 1939Apr 29, 1941Hydril Company Of CaliforniaWell pipe joint
US2258066 *Mar 11, 1940Oct 7, 1941Youngstown Sheet And Tube CoPipe joint
US2267923 *Sep 16, 1940Dec 30, 1941Arthur E JohnsonShear-reducing, dual verge thread for tool joints, etc.
US2532632 *Oct 4, 1948Dec 5, 1950Hydril CorpTubing and tubing joint
US2543100 *Dec 13, 1948Feb 27, 1951Engh Casper HScrew and nut mechanism
US2772102 *Apr 22, 1952Nov 27, 1956United States Steel CorpSealed threaded pipe joint
US2893759 *May 6, 1957Jul 7, 1959Smith Corp A OConically tapered screw-type casing joint with metal-to-metal seal
US2992019 *Jul 7, 1958Jul 11, 1961Hydril CoCasing joint having metal-to-metal sealing means responsive to fluid pressure
US3047316 *Oct 1, 1958Jul 31, 1962Atlas Bradford CompanyPacked pin and box drill pipe coupling with means preventing extrusion of packing ring
US3079181 *May 14, 1959Feb 26, 1963Shell Oil CoBox-and-pin-type threaded joint having different pitches and pitch diameters
US3109672 *Feb 15, 1960Nov 5, 1963United States Steel CorpThreaded tubing joint
US3158390 *Aug 28, 1962Nov 24, 1964George V WoodlingTapered thread fluid seal connection
US3224799 *Jun 21, 1965Dec 21, 1965Armco Steel CorpThreaded tube joint having a metal-to-metal seal
US3346278 *Apr 5, 1965Oct 10, 1967Superior Valve & Fittings CompTapered pipe thread
US3359013 *Sep 3, 1965Dec 19, 1967Hydril CoDeep well casing jont
US3467413 *Dec 14, 1967Sep 16, 1969Lorraine Escaut SaTriple-sealing pipe joint
US3468563 *Aug 7, 1967Sep 23, 1969VallourecSeparable joint for pipes
US3489437 *May 23, 1966Jan 13, 1970VallourecJoint connection for pipes
US3497246 *Dec 26, 1967Feb 24, 1970Exxon Production Research CoHigh pressure,low stress tubular connection
US3508771 *Jul 17, 1967Apr 28, 1970VallourecJoints,particularly for interconnecting pipe sections employed in oil well operations
US3572777 *May 5, 1969Mar 30, 1971Armco Steel CorpMultiple seal, double shoulder joint for tubular products
US3574373 *Feb 17, 1969Apr 13, 1971Vallourec Lorraine EscautSeparable connecting devices, especially for components of tubular braces
US3989284 *Apr 23, 1975Nov 2, 1976Hydril CompanyTubular connection
US3994516 *Mar 5, 1975Nov 30, 1976Otis Engineering CorporationTelescoping pipe coupling with improved pressure seal connection threads
US4040756 *Mar 5, 1976Aug 9, 1977Trw Canada LimitedDrill rod thread form
US4113290 *Sep 20, 1977Sep 12, 1978Tsukamoto Seiki Co., Ltd.Pressure tight joint for a large diameter casing
US4161332 *Jun 9, 1978Jul 17, 1979Hydril CompanyDovetail connection for pin and box joints
US4192533 *Feb 6, 1978Mar 11, 1980Hydril CompanyDovetail connection for pin and box joints
US4244607 *Jan 2, 1979Jan 13, 1981Hydril CompanyCylindrical threaded connection
US4373754 *Jun 4, 1981Feb 15, 1983Hydril CompanyThreaded connector
US4410204 *Jul 6, 1981Oct 18, 1983Dril-Quip, Inc.Connector
US4423893 *Feb 18, 1981Jan 3, 1984Holmes Horace DSelf-sealing tapered thread form
US4508375 *Sep 20, 1982Apr 2, 1985Lone Star Steel CompanyTubular connection
US4550937 *Dec 10, 1979Nov 5, 1985Vallourec S.A.Joint for steel tubes
US4600224 *Dec 23, 1983Jul 15, 1986Interlock Technologies CorporationTubular connection having a chevron wedge thread
US4600225 *Dec 23, 1983Jul 15, 1986Interlock Technologies CorporationTubular connection having a parallel chevron thread
US4822081 *Mar 23, 1987Apr 18, 1989Xl SystemsDriveable threaded tubular connection
USRE30647 *May 31, 1978Jun 16, 1981Hydril CompanyTubular connection
CH226987A * Title not available
DE568114C *Jan 24, 1931Jan 14, 1933Dardelet Threadlock CorpSchraubverbindung fuer Gestaenge in Bohrloechern
DE1132173B *Nov 5, 1956Jun 28, 1962Jeanne Brogiotti Geb GuillemotHolzschraube, insbesondere Schwellenschraube
FR1042192A * Title not available
GB137777A * Title not available
GB786652A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5454605 *Jun 15, 1993Oct 3, 1995Hydril CompanyTool joint connection with interlocking wedge threads
US5609440 *Jun 16, 1995Mar 11, 1997Hydril CompanyApparatus and method for arresting the propagation of a buckle in a pipeline
US6174001 *Mar 19, 1998Jan 16, 2001Hydril CompanyTwo-step, low torque wedge thread for tubular connector
US6254146Apr 23, 1999Jul 3, 2001John Gandy CorporationThread form with multifacited flanks
US6270127 *Jul 13, 2000Aug 7, 2001Hydril CompanyTwo-step, low torque wedge thread for tubular connector
US6283477 *Aug 2, 2000Sep 4, 2001Baker Hughes IncorporatedAnnular chamber seal
US6550821 *Mar 19, 2001Apr 22, 2003Grant Prideco, L.P.Threaded connection
US6554287Dec 9, 1999Apr 29, 2003Hydril CompanyCollapsing type seal for expandable tubular connections
US6578880 *Nov 19, 2001Jun 17, 2003Ramos, Beverly WattsWedgethread pipe connection
US6607220Oct 9, 2001Aug 19, 2003Hydril CompanyRadially expandable tubular connection
US6626471Aug 6, 2001Sep 30, 2003Hydril CompanyDouble flex seal for tubular connection
US6682101 *Sep 25, 2002Jan 27, 2004Beverly Watts RamosWedgethread pipe connection
US6817633Dec 20, 2002Nov 16, 2004Lone Star Steel CompanyTubular members and threaded connections for casing drilling and method
US7007984 *Nov 21, 2002Mar 7, 2006Torquelock CorporationHang-free thread design
US7156676Nov 10, 2004Jan 2, 2007Hydril Company LpElectrical contractors embedded in threaded connections
US7169239May 16, 2003Jan 30, 2007Lone Star Steel Company, L.P.Solid expandable tubular members formed from very low carbon steel and method
US7243957Dec 30, 2004Jul 17, 2007Hydril Company LpPseudo two-step connection
US7326015Aug 30, 2005Feb 5, 2008Hydril Company LlcElectrically insulated wedge thread connection
US7347459 *Apr 29, 2005Mar 25, 2008Gb Tubulars, Inc.Coupling for drilling-with-casing operations
US7380840Oct 26, 2004Jun 3, 2008Hydril CompanyExpandable threaded connection
US7404438Dec 6, 2006Jul 29, 2008United States Steel CorporationSolid expandable tubular members formed from very low carbon steel and method
US7458616Dec 30, 2004Dec 2, 2008Hydril CompanyThreads with perturbations
US7475917Mar 30, 2006Jan 13, 2009Hydril CompanyThreaded connection with variable flank angles
US7527304Dec 30, 2004May 5, 2009Hydril LlcFloating wedge thread for tubular connection
US7562911Jan 24, 2006Jul 21, 2009Hydril Usa Manufacturing LlcWedge thread with sealing metal
US7575255Jun 16, 2006Aug 18, 2009Hydril LlcWedge thread with high-angle metal seal
US7578039May 25, 2006Aug 25, 2009Hydril LlcDope relief method for wedge thread connections
US7578043Jun 8, 2006Aug 25, 2009Weatherford/Lamb, Inc.Coupling tubulars
US7607333Jan 25, 2007Oct 27, 2009Hydril LlcHelical groove for a tubular connection
US7621323Jul 23, 2008Nov 24, 2009United States Steel CorporationSolid expandable tubular members formed from very low carbon steel and method
US7661728May 13, 2004Feb 16, 2010Vallourec Mannesmann Oil & Gas FranceThreaded tubular connection with progressive axial thread interference
US7686350Mar 30, 2006Mar 30, 2010Hydril LlcMismatched flanks for a wedge thread
US7717478Aug 29, 2006May 18, 2010Hydril LlcScalloped wedge threads
US7810849May 23, 2007Oct 12, 2010Hydril Company LpThreads with perturbations
US7828337Feb 23, 2007Nov 9, 2010Hydril Company LpThreaded connection with wedge segments
US7850211Jan 24, 2007Dec 14, 2010Hydril CompanyWedge thread connections having a clearance gap volume
US7988205Jan 21, 2010Aug 2, 2011Hydril CompanyWedge thread with torque shoulder
US8029025Jul 28, 2005Oct 4, 2011Hydril CompanySingle taper wedge thread connection with mid-seal
US8075023Jan 28, 2008Dec 13, 2011Gb Tubulars, Inc.Coupling for drilling-with-casing operations
US8136846 *Nov 17, 2008Mar 20, 2012Gandy Technologies CorporationCylindrical tapered thread form for tubular connections
US8171613 *Dec 7, 2007May 8, 2012Hydril CompanyElectrically insulated wedge thread connection
US8177262Jul 28, 2005May 15, 2012Hydril Company LpMid-seal for expandable connections
US8220842Dec 30, 2009Jul 17, 2012Vallourec Mannesmann Oil & Gas FranceThreaded tubular connection which is resistant to bending stresses
US8496274Dec 2, 2011Jul 30, 2013Hydril CompanyStep-to-step wedge thread connections and related methods
US8534712Oct 28, 2011Sep 17, 2013Tenaris Connections LimitedTubular joint having wedge threads with surface coating
US8535762Oct 7, 2010Sep 17, 2013Tenaris Connections LimitedTubular joint having wedge threads with surface coating
US8668233Dec 21, 2006Mar 11, 2014Hydril CompanyThreaded connection with perturbed flanks
US8827322May 7, 2010Sep 9, 2014Sumitomo Metal Industries, Ltd.Threaded connection for drilling and operating hydrocarbon wells
EP1046779A1Apr 17, 2000Oct 25, 2000Hydril CompanyThreaded pipe connection
EP1106778A1Dec 11, 2000Jun 13, 2001Hydril CompanySeal for expandable tubular connections
EP1179700A2 *Aug 9, 2001Feb 13, 2002Hydril CompanyDouble flex seal for tubular connection
EP1887269A1 *Aug 7, 2006Feb 13, 2008BEZA S.p.A.Composable pipework having a plurality of modular tubular ducts
WO1998053177A1May 20, 1998Nov 26, 1998Hydril CoStress reduction groove for tubular connection
WO2001029475A1 *Oct 14, 2000Apr 26, 2001Beverly Watts RamosOpen type wedgethread connection
WO2002075197A1 *Mar 19, 2002Sep 26, 2002Grant Prideco LpThreaded connection
WO2003076837A2 *Mar 3, 2003Sep 18, 2003Ramos Beverly WattsWedgethread pipe connection
WO2004106797A1May 13, 2004Dec 9, 2004Vallourec Mannesmann Oil & GasThreaded tubular connection with progressive axial thread interference
WO2005108848A2 *Apr 29, 2005Nov 17, 2005Gb Tubulars IncImproved coupling for drilling-with-casing operations
WO2006073861A1Dec 22, 2005Jul 13, 2006Hydril Co LpPseudo two-step connection
WO2007016074A1Jul 25, 2006Feb 8, 2007Hydril Co LpMid-seal for expandable connections
WO2008017454A1 *Aug 7, 2007Feb 14, 2008Beza S P AComposable pipework having a plurality of modular tubular ducts
WO2010118839A1Apr 9, 2010Oct 21, 2010Vallourec Mannesmann Oil & Gas FranceTubular component for drilling and operating hydrocarbon wells, and resulting threaded connection
WO2010133299A1 *May 7, 2010Nov 25, 2010Vallourec Mannesmann Oil & Gas FranceThreated connection for drilling and operating hydrocarbon wells
WO2011048455A2Oct 11, 2010Apr 28, 2011Tenaris Connections LimitedA tubular joint having wedge threads with surface coating
WO2011151028A2May 24, 2011Dec 8, 2011Vallourec Mannesmann Oil & Gas FranceThreaded end of a tubular component for drilling or working hydrocarbon wells, and resulting connection
WO2012049194A1Oct 12, 2011Apr 19, 2012Sumitomo Metal Industries, LtdThreaded tubular component and resulting connection
WO2012062426A1Nov 2, 2011May 18, 2012Sumitomo Metal Industries, Ltd.Process for coating a threaded tubular component, threaded tubular component and resulting connection
WO2012069154A1Nov 15, 2011May 31, 2012Sumitomo Metal Industries, Ltd.Method and device for inspecting a threading of a tubular connection used in the oil industry
WO2012089304A1Dec 12, 2011Jul 5, 2012Sumitomo Metal Industries, Ltd.Process for coating a threaded tubular component, threaded tubular component and resulting connection
WO2012089305A1Dec 12, 2011Jul 5, 2012Sumitomo Metal Industries, Ltd.Threaded connection for drilling and working hydrocarbon wells
WO2013038072A1Sep 10, 2012Mar 21, 2013Vallourec Mannesmann Oil & Gas FranceAssembly for producing a threaded joint for the drilling and operation of hydrocarbon wells, and resulting threaded joint
WO2013053450A1Oct 4, 2012Apr 18, 2013Vallourec Mannesmann Oil & Gas FranceThreaded tubular component and resulting connection
WO2013098490A1Dec 20, 2012Jul 4, 2013Vallourec Mannesmann Oil & Gas FranceThreaded tubular component and method for coating such a threaded tubular component
WO2014041017A1Sep 11, 2013Mar 20, 2014Vallourec Oil And Gas FranceProcess for producing a dry polyamide-imide film with high galling resistance on a threaded tubular component from an aqueous dispersion which is free of carcinogenic substances
Classifications
U.S. Classification285/334, 285/390
International ClassificationF16L15/06, E21B17/042
Cooperative ClassificationF16L15/001, E21B17/0423, E21B17/042, F16L15/002, F16L15/003
European ClassificationE21B17/042B, F16L15/00B4, F16L15/00B2, F16L15/00B
Legal Events
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Oct 16, 2001FPAYFee payment
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Jun 28, 1994FPExpired due to failure to pay maintenance fee
Effective date: 19940628