MXPA00009164A - Two-step, low torque wedge thread for tubular connector - Google Patents

Abstract

A threaded pipe connection is disclosed that includes a box member (112) and a pin member (111). The box member (12) has two wedge thread steps each with a tapered, internal, generally dovetial-shaped wedge thread (114) having stab flanks (118), load flanks (116), roots (120), and crests (124). The pin member (111) has two wedge thread steps each with a tapered, external, generally dovetail-shaped wedge thread (115) having stab flanks (119), load flanks (117), roots (121), and crests (125). The internal thread (114) of the box member increases in width in one direction. The external thread (115) of the pin member increases in width in the other direction so that complementary flanks of the box member thread move into engagement during rotational make-up of the connection. The roots and crests of at least one wedge thread step on the box member (112) are dimensioned to contact complementary roots and crests on the pin member (111) upon final make-up. Also, stab (118) and load flanks (116) of at least one wedge thread step on the box member (112) are dimensioned to contact complementary stab (119) and load flanks (117) on the pin member (111) upon final make-up.

Description

Threaded Low Torque Wedge, Two Stage, for Tubular Connector Field of the Invention The invention relates to threaded tubular joints usable in the drilling and production of oil and gas wells, such as tubing, lining, tube lined, and tube drilling, commonly known collectively as tubular products for oilfields. More particularly, the invention relates to a tubular joint for connecting male (pin) and female (box) components without having to apply tremendous pressure for their preparation. Background of the Invention The use of coiled tubular connections to join flow conductors in an end-to-end relationship to form a continuous flow path to transport fluid under pressure is well known. Tubular oilfield products all use threaded connections to connect adjacent sections of conductors or pipes. Examples of those threaded end connections designed for use in tubular products for oilfields are disclosed in U.S. Patent Nos. 2,239,942; 2,992,019; 3,359,013; 4,917,409; RE 30,647; and it 34,467, all assigned to the assignee of the present invention. In US Patent No. RE 30,647 to Blose, a particular thread shape or structure is disclosed for a tubular connection that provides an unusually strong joint, while at the same time controlling the pressure and deformation in the bolt and box components connected within acceptable levels. The bolt component is equipped with at least one generally external thread in the form of a dovetail, whose thickness increases in one direction along the bolt, while the box component is equipped with at least one internal thread in the form of a glue of milano that joins, whose thickness increases in the other direction. In this way, the mating of the helical threads provides a wedge-shaped gear of the opposite flanks of the bolt and the box that limit the extent of relative rotation between the bolt and box components, and define a condition of forced arrangement that complete the connection. In this thread structure, the shoulder angles of the flanks as well as the thickness of the thread can be used to control the conditions of pressure and deformation that occur before loading, induced in the components of bolt and box for a torque prepared Dadaist. Therefore, arming the thread structure to an application or particular use, the tubular connection or joint is limited only by the properties of the selected materials. The wedge thread has been proven as a reliable sealing mechanism in threaded connections. The actions of lace and wedge of the threads create a sufficient obstruction in the bases, crests, load flanks and transfer flanks to effect the thread seal. The friction drag caused by the clogging of the threads must be overcome with torsion during the preparation process. The longer the threaded obstruction area, the greater the torque requirements for the preparation. As the connection diameters increase, eg, for diameters of 10"or greater, the threaded obstruction area increases until the point where the required torsion is not practical for field operations is reached. FIGURE 1, a prior connector in science 10 includes a bolt component 11 and a box component 12. The box component 12 has a sharp, internal thread structure, generally in the form of a dovetail 14 formed and adapted to engage with an externally threaded complementary thread structure, generally in the form of a dovetail 15 formed in a bolt component 11 to mechanically secure the box and bolt components in a releasable manner.

The internal thread 14 of the box component 12 has transfer flanks 18, load flanks 16, bases 20, and ridges 24. The thread progressively increases its thickness at a uniform index in a direction substantially throughout the helical length of the thread 14. The outer rock 15 of the pin component 11 has transfer flanks 19, load flanks 17, bases 21, and ridges 25. The thread progressively increases in thickness at a uniform rate in the other direction substantially over the entire helical length of the thread 15. Thicknesses of threads that increase in opposite manner and the edge of the threads 14 and 15, causes the complementary flanks, bases and crests of the respective threads, to move towards a forced gear during the rotary preparation of the connection and form sealing surfaces that resist the flow of fluids between the threads at the moment of the rotating preparation of the connection. The bolt component 11 or the box component 12 defines the longitudinal axis 13 of a preparation connection 10. The bases and crests of the box and bolt components are flat and parallel to the longitudinal axis of the connection and have sufficient thickness to prevent any permanent deformation of the threads when preparing the connection.

Summary of the Invention A threaded pipe connection is disclosed, and includes a box component and a bolt component. The box and bolt components are formed in a two-step configuration, having a greater pitch and a smaller pitch. The box component has a sharp, internal thread, generally in the form of a dovetail through both threads, with crossed flanks, load flanks, bases and ridges. The bolt component also has a sharp, external thread, generally in the form of a dovetail through both threaded passages with traversed flanks, load flanks, bases and crests. The internal thread of the box component increases its thickness in one direction while the external thread increases its thickness in the other direction in such a way that the complementary flanks of the respective threads move towards a gear during the rotary preparation of the connection. The bases and ridges of at least one step of the wedge thread in the box component are dimensioned so that they have contact with the complementary bases and ridges in the pin component for the final preparation. In a step of the wedge thread in the box component having bases and ridges dimensioned so as to have contact with the complementary bases and ridges in the pin component, the traversed and load flanks in the box component are dimensioned to have contact with the traversed flanks and complementary load on the bolt component for the final preparation. Also, at least one of the traversed and load flanks of the other wedge thread pitch of the box component are dimensioned so that they remain clear of the corresponding traversed and load flanks of the other wedge thread pitch in the pin component. for the final preparation. According to one or more embodiments of the invention, there may be a gap between the complementary traversed flanks of one of the threaded passages of the box and bolt components above the final preparation. There may be a gap between the complementary traversed flanks of one of the threaded passages of the box and bolt components above the final preparation. There may be a breach in the flank traversed and the load flank of one of the thread passages above the final preparation. There may be a gap between the bases and complementary ridges of the box and bolt components of one of the thread passages above the final preparation. There may be a gap in one or more of the complementary load flanks, traversed flanks and bases and ridges of the box and bolt components above the final preparation. The bases and ridges of both threads can come into contact during preparation before contact of the traversed flanks and load of at least one thread pitch above the final preparation. One of the wedge threads can be a clogged wedge thread pitch and the other can be a clear wedge thread pitch. A greater amount of clogging at the base and ridge may occur in the clogged wedge threading step than in the step of the wedge threading that is clear above the final preparation. There may be obstruction at the base and ridge in the clogged wedge thread pitch and there may be a base and crest clearance in the clear wedge thread pitch above the final preparation. The advantages may include one or more of the following. By minimizing the thread clogging area without sacrificing the sealing or structural integrity of the connector, it becomes practical to install larger diameter connectors at a much lower torsion. Also, by incorporating a two-step structure, high resistance to compression and / or impact loading can be achieved, while maintaining sensitivity to the torsional restrictions of the field equipment for preparation. In addition, the two-step configuration of the invention will reduce the amount of torque required to generate the contact pressure necessary to create a seal, while still providing the necessary threads for structural purposes. Another advantage and feature will be apparent from the following description, including the drawings and the claims. Brief Description of the Drawings FIGURE 1 is a side view, partially in section, of a tubular joint prior to science; FIGURE 2 is a side view of an external thread structure of bolt component and an internal thread structure of box component according to an embodiment of the invention; FIGURE 3 is an enlarged cross-section of a tubular seal at a point of engagement between a ridge with bolt component and a base with box component in the thick section of the box component in accordance with an embodiment of the invention; FIGURE 4 is an enlarged cross-section of a tubular seal at a point of engagement between a crest with bolt component and a base with box component in the thin section of the box component in accordance with an embodiment of the invention. Detailed Description With reference to the drawings in which similar reference characteristics are used for similar parts through the various views, FIGURES 2, 3 and 4 illustrate a screw connection in the form of a wedge or pipe joint, generally referred to with the number 110, according to an embodiment of the invention. As shown in FIGURE 2, the internal thread 114 of the box component 112 is formed in a two-step wedge configuration, providing two wedge-shaped threads, each with traversed flanks 118, 218, load flanks 116, 216, bases 120, 220 and ridges 124, 224. The thread progressively increases in thickness at a uniform rate in a direction substantially the entire helical length of the thread 114. The external thread 115 of the component 111 is formed with a wedge configuration of two steps, providing two steps of wedge-shaped thread each with crossed flanks 119, 219, load flanks 117, 217, bases 121, 221, and ridges 125, 225. The thread increases in thickness progressively at a uniform index in the other direction substantially to the entire helical length of the thread 115. The thicknesses of Threads that increase oppositely and the edge of the threads 114 and 115 causes that the complementary flanks, bases and crests of the respective threads, move towards a forced gear during the rotary preparation of the connection and form sealing surfaces that resist the flow of fluids between the threads of a passage, while leaving a space between the threads of the other step above the rotary preparation of the connection.

As used herein, and as is conventionally understood where the tubular joints are connected in a vertical position, such as when preparing the rope of a pipe to lower it to the borehole of a well, the term "load flank" designates the surface of the side wall of a thread that moves away from the outer end portion of the respective bolt or box component in which the thread is formed and supports the weight of the lower tubular slope in the well bore. The term "crossed flank" designates that side of the surface of the wall of the thread that is toward the outer end portion of the respective bolt or housing component and supports the weight of the upper tubular component during the initial preparation of the joint. FIGURES 3 and 4 are enlarged cross-sections in which one or more embedments exist in positions 2 or 3 shown in FIGURE 2. As shown in FIGURE 3, the bases and crests in a pitch of the bolt component 111 are dimensioned to eliminate the radial space with complementary bases and ridges in a passage of the box component 112 during the preparation of the connection 110. Also the traversed flanks and the load flanks of a pitch of a bolt component 111 are dimensioned to eliminate the space between the traversed flanks and the complementary load flanks in the box component of a step 112 during the preparation of the connection 110. For example, the bases 121 and ridges 125 of the minor pitch of the bolt component 111 can be dimensioned to eliminate the radial space with bases 120 and complementary ridges 124 in the smaller step of the component of box 112 during the preparation of the connection 110. Also, the traversed flanks 119 and the load flanks 117 of the minor pitch of the bolt component 111 can be dimensioned to eliminate the space between the traversed flanks 118 and the load flanks 116 complementary to the box component 112 during the preparation of the connection 110. In other words, the screw bases 121 and the thread crests 125 of a pin component 111 come into contact with the corresponding screw surfaces of the box component 112, once they cause the adjusting gasket and the traversed flanks 119 and the load flanks 117 of the bolt component 111 to come into contact with obstruction with the corresponding thread surfaces of the box component 112, once the adjustment of the joint force has been made. As shown in FIGURE 4, the bases and ridges in the other step of the bolt component 111 are dimensioned to leave a radial space between the bases and complementary ridges in the other passage of the box component 112 during the preparation of the connection 110. . Also they load flanks of the other pitch of the bolt component 111 are dimensioned to leave space between the complementary load flanks in the other passage of the box component 112. For example, the bases 221 and ridges 225 in the larger pitch of the bolt component 111 they are dimensioned to leave a radial space 250 between the bases 220 and complementary ridges 224 in the greater pitch of the box component 112 during the preparation of the connection 110. Also the load flanks 217 in the larger pitch of the bolt component 111 are dimensioned to leave a space 255 between the complementary load flanks 216 in the larger step of the box component 112 during the preparation of the connection 110. In other words, the thread bases 221 and the thread crests 225 of the pin component 111 remain free of the corresponding thread surfaces of the box component 112, to make the pressure of the seal and the load flanks 217 of the bolt component 111 remain free of the corresponding load flanks 216 of the box component 112 once the force pressure of the gasket has been made. Alternatively, the traversed flanks 219 of the bolt component 111 can be dimensioned to remain as free space of the traversed flanks 218 complementary to the box component 112 or the traversed flanks or load flanks of the bolt component 111 remain as free space of the bolt components 111. Thread structures corresponding to the box component 112 for the preparation of the connection. Also, although FIGURE 4 shows spaces between the bases and crests and the load flanks, either can remain as free space while the other comes into contact with obstruction in the preparation of the connection. Similarly, any of the bases and crests or flanks traversed may remain as free space while the other comes into contact with obstruction for the preparation of the connection. The revealed configuration has many different advantages. The two-step structure allows high resistance to compression and / or load impact, while retaining sensitivity to the torsional restrictions of existing field equipment. In addition, the two-step structure reduces the amount of torque required to generate the contact pressure necessary to create a seal, while providing the necessary threads for structural purposes. The disclosed configuration minimizes the thread clogging area without sacrificing the seal or structural integrity of the connector. Because the connectors can be installed at a much lower torsion, this invention is particularly advantageous in applications using large diameter connectors, such as in the coating of a surface.

It will be understood that certain characteristics and subcombinations are useful and can be used without reference to other characteristics and subcombinations. This is contemplated and is within the scope of the claims. Because many embodiments of the invention can be made without departing from the scope, it should be understood that all material set forth herein or shown in the accompanying drawings should be construed as illustrative and not in a limited sense. While the present invention has been described with respect to a limited number of preferred embodiments, those skilled in science will appreciate numerous modifications and variations. The appended claims are intended to cover all those modifications and variations that occur to one of ordinary skill in science.

Claims (28)

Claims

1. A threaded tube connection, comprising: a box component having a two-step wedge thread configuration comprising two wedge-threaded passages each with a sharp, internal wedge thread, generally in the form of a dovetail which has crossed flanks, load flanks, bases and crests, the internal thread increasing in thickness in one direction; a bolt component having a two-step wedge thread configuration including two thread passages each with a sharp, external wedge thread, generally in the form of a dovetail, having traversed flanks, load flanks, bases and crests, the external thread increasing its thickness in the other direction such that the complementary flanks of the box component thread move to engage during the rotary preparation of the connection; the bases and ridges of at least one step of the wedge thread in the box component are dimensioned so that complementary bases and ridges in the pin component come into contact with the final preparation; in the pitch of a wedge thread in the box component having bases and ridges sized to come into contact with complementary bases and ridges in the component of bolt, the traversed and load flanks in the box component are dimensioned so that they come into contact with traversed and complementary load flanks on the bolt component towards the end of the preparation; and at least one of the traversed and load flanks of the other wedge thread pitch of the box component are dimensioned to remain as free space of the traversed and load flanks of the other wedge thread pitch of the pin component towards the flange. final preparation.

The connection of claim 1, wherein there is a space between the flanks traversed from the other of the wedge-shaped threads towards the final preparation.

The connection of claim 1, wherein there is a space between the load flanks of the other of the wedge-shaped threads towards the final preparation.

The connection of claim 1 wherein there is space between the traversed flanks and the load flanks of the other of the wedge threads to the final preparation.

5. The connection of claim 1 wherein there is a gap between the bases and the crests of the other of the wedge thread passages towards the final preparation.

6. The connection of claim 2 wherein there is a gap between the bases and ridges of the other of the wedge threads to the final preparation.

7. The connection of claim 3 wherein there is a gap between the bases and crests of the other of the wedge thread passages towards the final preparation.

The connection of claim 4 wherein there is a gap between the bases and crests of the other of the wedge-shaped threads towards the final preparation.

The connection of claim 1 wherein the bases and ridges of both wedge-shaped threads come into contact during preparation before coming into contact with the traversed and load flanks of at least one wedge thread passage toward the flange. final preparation.

The connection of claim 1 wherein one of the wedge-threaded passages is a wedge-shaped thread pitch of obstruction and another is a wedge-shaped thread pitch with clearance; and a greater amount of base and crest obstruction occurs in the wedge pitch of clogging wedge than in the wedge pitch of free space toward the final preparation.

11. The connection of claim 1 wherein one of the wedge-threaded passages is a wedge-shaped pitch of obstruction and the other is a step of wedge thread with free space; and there is obstruction in the base and ridge in the thread pitch in wedge of obstruction and there is free space in the base and crest in the step of wedge thread with free space towards the final preparation.

The connection of claim 1 wherein the bases and ridges of the box and bolt components are of sufficient thickness to prevent any permanent deformation of the threads toward the final preparation.

13. The connection of claim 1, wherein the bases and crests of the box and bolt components are flat and parallel to the longitudinal axis of the connection.

The connection of claim 1, wherein the contact between the bases and ridges of at least one thread pitch in the box component and the complementary bases and ridges in the pin component occurs prior to contact between the traversed flanks and load of at least one thread step of the box component and the complementary traversed and load flanks in the bolt component.

15. A method for reducing torsion-induced pressure in a threaded pipe connection, the method includes: providing a box component having a two-step wedge thread configuration comprising two ! Wedge threads each with a wedge in a sharp wedge, Internal, generally in the form of a dovetail that has crossed flanks, load flanks, bases and crests, the internal thread increases in thickness in one direction; I provide a bolt component that has a two-step wedge thread configuration comprising two I steps of wedge threads each with a wedge thread Sharp, external, generally in the form of a dovetail, and having crossed flanks, load flanks, bases and crests, the external thread increases its thickness in the other direction so that the complementary flanks of the first thread of the box component move to engage during the rotary preparation of the connection; dimensioning the bases and ridges of at least one wedge thread pitch in the box component to contact the complementary bases and ridges in the pin component during the rotary preparation of the connection; dimensioning, in the step of wedge thread in the box component having bases and crests dimensioned il to contact bases and complementary ridges in the bolt component, the traversed and load flanks in the box component for contacting traversed flanks and complementary loading on the bolt component towards the final preparation; Y dimensioning at least one of the traversed and load flanks of the other wedge thread pitch of the box component so that it remains as free space of traversed flanks and load flanks of the other wedge thread in the pin component towards the final preparation .

The method of claim 15, wherein the traversed flanks of the gold wedge thread passage in the box component are dimensioned to remain as free space of complementary traversed flanks in the pin component toward the final preparation.

The method of claim 15, wherein the load flanks of the other wedge thread pitch in the box component are dimensioned to remain free of complementary load flanks in the pin component toward the final preparation.

The method of claim 15, wherein the traversed and load flanks of the other wedge thread pitch of the box component are dimensioned so that they remain free of traversed flanks and load flanks on the bolt component toward the final preparation .

19. The method of claim 15, further comprising: dimensioning the bases and ridges of the other wedge thread pitch of the box component such that there is a gap the bases and complementary ridges in the bolt component towards the final preparation.

The method of claim 16, further comprising: dimensioning the bases and ridges of the other wedge thread pitch of the box component such that there is a gap between the bases and complementary ridges on the bolt component toward the preparation final .

The method of claim 17, further comprising: dimensioning the bases and ridges of the other wedge thread pitch of the box component such that there is a gap between the bases and complementary ridges on the bolt component toward the preparation final .

22. The method of claim 18, further comprising: dimensioning the bases and ridges of the other wedge thread pitch of the box component such that there is a gap between the bases and complementary ridges on the bolt component toward the preparation final .

23. The method of claim 15, further comprising: sizing the bases and ridges of both wedge-shaped threads so that they come into contact during the preparation before of the contact of the traversed flanks and load of at least one step of wedge thread towards the final preparation.

The method of claim 15, wherein one of the wedge-threaded passages is a clogged wedge thread pitch and the other is a free wedge thread pitch., the method also includes: dimensioning the thread pitch in wedge of obstruction to have a greater amount of obstruction in the base and crest than the step of free wedge thread towards the final preparation.

25. The method of claim 15, wherein one of the wedge-threaded passages is a clogged wedge thread pitch and the other is a free wedge thread pitch, the method further including: dimensioning the thread pitch in wedge of obstruction so that there is obstruction in the base and crest towards the final preparation; and dimensioning the thread step in free wedge so that there is a free space in the base and crest towards the final preparation.

26. The method of claim 15, further includes: providing the bases and ridges of the wedge threads of two box and bolt components that are flat and parallel to the longitudinal axis of the connection.

27. The method of claim 15, further includes: provide the bases and ridges of the wedge threads of the box and bolt components with sufficient thickness to prevent any permanent deformation of the wedge threads towards the final preparation. The method of claim 15 further includes: sizing the bases and ridges in at least one wedge thread pitch of the box component to contact complementary bases and ridges in the wedge thread pitch of the pin component before contact between the traversed and load flanks of at least one wedge thread pitch in the box component for contacting traversed and complementary load flanks in the wedge thread pitch of the pin component. Summary of the invention A threaded pipe connection is disclosed, which includes a box part and a bolt part. The box piece has two stages of wedge threading, each with a wedge thread, usually in the form of a dovetail, internal, tapered, having sign edges, loading edges, bases and cups. The bolt piece has two stages of wedge threading, each with a wedge thread, usually in the form of a dovetail, external, tapered, having sign edges, loading edges, bases and cups. The internal threading of the box piece increases in thickness, in one direction. The external threading of the bolt piece increases in thickness in the other direction, so that the complementary edges of the threading piece of the box piece move to engage during the rotary procedure of the connection. The bases and cups of at least one stage of wedge threading in the box piece have a dimension such that they make contact with the bases and complementary cups in the bolt piece, in the final procedure. Similarly, the edges of signaling and loading, of at least one step of wedge threading in the box piece, have a dimension such that they make contact with the signaling and loading edges in the bolt piece, in the final process.