CN221144335U - Petroleum pipe threaded joint - Google Patents

Abstract

The utility model provides a petroleum pipe threaded joint. The petroleum pipe nipple includes: the connecting pipe and the coupling of threaded connection are equipped with in proper order along axial direction between connecting pipe and the coupling: the thread part comprises an external thread arranged on the connecting pipe and an internal thread arranged on the coupling; the radial sealing structure comprises a tangential arc sealing surface and a sealing conical surface which are in interference fit, one of the arc sealing surface and the sealing conical surface is arranged on the connecting pipe, the other of the arc sealing surface and the sealing conical surface is arranged on the coupling, and the radial sealing structure is used for sealing a gap between the connecting pipe and the coupling in the radial direction; and the axial sealing structure is used for sealing a gap between the connecting pipe and the coupling in the axial direction. The technical scheme of the utility model adopts line contact sealing, so that the contact stress distribution is more uniform.

Description

Petroleum pipe threaded joint

Technical Field

The utility model relates to the technical field of petroleum pipe threaded connection, in particular to a petroleum pipe threaded connector.

Background

In the exploitation of oil and natural gas, an oil casing is a necessary exploitation tool. Several hundred oil sleeves are connected through threaded joints to form an oil-gas channel. The existing oil sleeve joint comprises an API circular thread, a buttress thread and a special threaded connection, wherein the API circular thread and the buttress thread have no air sealing capability and cannot be used for natural gas exploitation, the special threaded joint generally consists of a torque shoulder, a metal seal and a connecting thread, the special threaded joint has good air sealing performance, and the special threaded joint is generally adopted for natural gas exploitation.

Currently, a prior art known to the inventors (chinese patent CN 2886276Y) discloses a hermetically sealed serrated threaded joint and oil casings and couplings employing the threaded joint, comprising an external threaded joint and an internal threaded joint. The inner wall of the internal thread fitting joint is sequentially provided with an internal thread, a sealing conical surface and a positioning shoulder. The external thread, the sealing conical surface and the end surface shoulder are correspondingly arranged on the outer wall of the external thread piece joint. When the connector is used, radial interference occurs to the internal thread and the external thread, and radial interference occurs to the sealing conical surface and the sealing conical surface respectively, and axial interference is formed between the positioning shoulder and the end surface shoulder. In the scheme, two sealing conical surfaces are matched (namely, the surfaces are contacted) to realize sealing, and if machining errors exist in the conical degrees of the two conical surfaces, uneven contact stress distribution on the sealing surfaces can be caused.

Disclosure of utility model

The utility model mainly aims to provide a petroleum pipe threaded joint, which can solve the problem of uneven sealing surface contact stress distribution caused by sealing by adopting surface contact in the prior art.

To achieve the above object, according to an aspect of the present utility model, there is provided a petroleum pipe threaded joint comprising: the connecting pipe and the coupling of threaded connection are equipped with in proper order along axial direction between connecting pipe and the coupling: the thread part comprises an external thread arranged on the connecting pipe and an internal thread arranged on the coupling; the radial sealing structure comprises a tangential arc sealing surface and a sealing conical surface which are in interference fit, one of the arc sealing surface and the sealing conical surface is arranged on the connecting pipe, the other of the arc sealing surface and the sealing conical surface is arranged on the coupling, and the radial sealing structure is used for sealing a gap between the connecting pipe and the coupling in the radial direction; and the axial sealing structure is used for sealing a gap between the connecting pipe and the coupling in the axial direction.

Further, the circular arc sealing surface is arranged on the outer wall surface of the connecting pipe, the sealing conical surface is arranged on the inner wall surface of the coupling, and a space is reserved between the axial sealing structure and a tangent line between the circular arc sealing surface and the sealing conical surface.

Further, the circular arc sealing surface and the sealing cone surface form a first clearance groove for storing grease at a spacing, and the maximum groove width of the first clearance groove is 0.4mm to 0.6mm.

Further, the petroleum pipe threaded joint further includes a storage groove structure provided between the threaded portion and the radial seal structure in the axial direction, the storage groove structure including: a cylindrical surface provided on one of the connection pipe and the coupling; and a cylindrical hole formed in the other of the connection pipe and the collar, the cylindrical surface and the cylindrical hole defining a second clearance groove for storing grease.

Further, the distance L between the tangent line between the arc sealing surface and the sealing conical surface and the end surface of the connecting pipe extending into the coupling is more than or equal to 3.5mm; and/or the taper of the sealing conical surface is 1:8, and the arc radius R of the arc sealing surface is 45mm to 68mm.

Further, the axial seal structure includes: the end part is arranged at one end of the connecting pipe; a shoulder disposed on the collar; a first concave-convex structure provided on the end portion; the second concave-convex structure is arranged on the shoulder, and the second concave-convex structure is in concave-convex fit and interference fit with the first concave-convex structure.

Further, the first concave-convex structure comprises a protrusion, a first horizontal side surface and a groove which are connected in sequence, the second concave-convex structure comprises a shoulder groove, a second horizontal side surface and a shoulder protrusion which are connected in sequence, the protrusion is matched with the shoulder groove in a concave-convex mode, the shoulder protrusion is matched with the groove in a concave-convex mode, and the first horizontal side surface is in butt joint with the second horizontal side surface.

Further, the interference between the first horizontal side and the second horizontal side is 0.05mm to 0.1mm.

Further, the first concave-convex structures and the second concave-convex structures are multiple, the first concave-convex structures are sequentially connected in the radial direction, and the second concave-convex structures are sequentially connected in the radial direction; the first concave-convex structure further comprises a groove inclined surface connected with the groove, the second concave-convex structure further comprises a convex inclined surface connected with the shoulder bulge, and the groove inclined surface is in clearance fit with the convex inclined surface.

Further, the gap between the groove inclined surface and the protrusion inclined surface is 0.05mm to 0.15mm; and/or the slopes of the groove inclined plane, the convex inclined plane and the sealing conical surface are the same.

By adopting the technical scheme of the utility model, the circular arc sealing surface and the sealing conical surface are arranged, so that the petroleum pipe threaded joint has strong air sealing capability and high sealing reliability, and the sealing performance is slightly influenced by on-site buckling operation. After the connecting pipe and the coupling are screwed up, the circular arc sealing surface and the sealing conical surface are in interference fit in the radial direction, and the circular arc sealing surface and the sealing conical surface are tangent, namely in line contact.

Drawings

The accompanying drawings, which are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and together with the description serve to explain the utility model. In the drawings:

FIG. 1 shows a schematic structural view of an embodiment one of a petroleum pipe threaded joint of an embodiment of the present utility model;

FIG. 2 shows an enlarged view at A of the petroleum pipe nipple of FIG. 1;

FIG. 3 shows an exploded view of the petroleum pipe threaded joint of FIG. 2;

FIG. 4 shows a schematic structural view of a second embodiment of a petroleum pipe threaded joint according to an embodiment of the present utility model;

FIG. 5 shows an enlarged view of the embodiment of FIG. 4 at B of a petroleum pipe threaded joint;

FIG. 6 shows an exploded view of the petroleum pipe threaded joint of FIG. 5;

FIG. 7 shows a schematic diagram of a prior art petroleum pipe threaded joint;

FIG. 8 shows an enlarged view of the petroleum pipe nipple of FIG. 7 at C;

fig. 9 shows an exploded view of the petroleum pipe nipple of fig. 8.

Wherein the above figures include the following reference numerals:

1. A connecting pipe; 2. an external thread; 3. a cylindrical surface; 4. an end portion; 5. coupling; 6. an internal thread; 7. a cylindrical hole; 8. a shoulder; 9. arc sealing surface; 10. a protrusion; 11. a first horizontal side; 12. a groove; 13. the shoulder is convex; 14. a second horizontal side; 15. shoulder grooves; 16. sealing the conical surface; 17. a first clearance groove; 18. a second clearance groove; 19. groove inclined planes; 20. a convex inclined plane; 100. a tube; 200. a tube end; 500. a collar member; 900. a first metal sealing surface; 1500. a shoulder portion; 1600. a second metal sealing surface.

Detailed Description

It should be noted that, without conflict, the embodiments of the present utility model and features of the embodiments may be combined with each other. The utility model will be described in detail below with reference to the drawings in connection with embodiments.

In the prior art known to the inventors, in order to improve the problem of uneven contact stress distribution of the sealing surface of the threaded joint, an optimized sealing surface structure, a teflon sealing ring, a special sealing thread compound or the like is adopted, but the above solutions do not achieve a good improvement effect.

In one prior art known to the inventors, as shown in fig. 7 to 9, on one hand, the first metal sealing surface 900 on the pipe 100 and the second metal sealing surface 1600 on the coupling member 500 are tapered surfaces, and the taper is 1:2 to 1:4, and the contact stress is unevenly distributed on the contact surfaces due to the influence of the taper tolerance, so that the sealing effect is poor. On the other hand, since the first metal seal face 900 and the second metal seal face 1600 are both closer to the shoulder 1500, the magnitude of the make-up torque may seriously affect the distribution of the contact stress on the seal faces, thereby affecting the sealing effect. And the pipe end 200 and the shoulder 1500 form an inclined shoulder, and because the thicker shoulder has high rigidity, when the sealing surfaces are in interference fit, the external thread nose is not easy to deform radially, so that the stress concentration of the sealing surfaces is caused to generate sticking failure. And if the pipe end is bored to reduce the thickness of the externally threaded nose, the torque capacity of the joint is insufficient.

Therefore, in order to solve the technical problems, the application provides a petroleum pipe threaded joint.

Example 1

Referring to fig. 1 to 6, the present utility model provides a petroleum pipe threaded joint. The petroleum pipe threaded joint of this embodiment includes: the connecting pipe 1 and the coupling 5 of threaded connection are equipped with in proper order along axial direction between connecting pipe 1 and the coupling 5: the thread part comprises an external thread 2 arranged on the connecting pipe 1 and an internal thread 6 arranged on the coupling 5; the radial sealing structure comprises a tangential and interference fit arc sealing surface 9 and a sealing conical surface 16, one of the arc sealing surface 9 and the sealing conical surface 16 is arranged on the connecting pipe 1, the other of the arc sealing surface 9 and the sealing conical surface 16 is arranged on the coupling 5, and the radial sealing structure is used for sealing a gap between the connecting pipe 1 and the coupling 5 in the radial direction; and the axial sealing structure is used for sealing a gap between the connecting pipe 1 and the coupling 5 in the axial direction.

Through the arrangement, through the arrangement of the circular arc sealing surface 9 and the sealing conical surface 16, the petroleum pipe threaded joint has strong air sealing capability and high sealing reliability, and the sealing performance is slightly influenced by on-site buckling operation. After the connecting pipe 1 and the coupling 5 are screwed up, the circular arc sealing surface 9 and the sealing conical surface 16 are in interference fit in the radial direction, and the circular arc sealing surface 9 and the sealing conical surface 16 are tangent, namely in line contact. Further, the circular arc sealing surface 9 and the sealing conical surface 16 can also form metal/metal sealing, and the sealing effect is good.

As shown in fig. 1 to 6, in the first embodiment of the present utility model, the circular arc sealing surface 9 is provided on the outer wall surface of the connection pipe 1, the sealing tapered surface 16 is provided on the inner wall surface of the coupling 5, and a space is provided between the axial sealing structure and the tangent line between the circular arc sealing surface 9 and the sealing tapered surface 16.

Through above-mentioned setting, have the interval between radial seal structure and the axial seal structure, sealing performance is difficult for buckling the influence of moment of torsion, and sealing performance is good to can improve the sealing reliability of joint.

In one embodiment of the utility model, the distance L between the tangent line between the circular arc sealing surface 9 and the sealing conical surface 16 and the end surface of the connecting pipe 1 extending into the coupling 5 is more than or equal to 3.5mm.

In the scheme, a space is reserved between the radial sealing structure and the axial sealing structure, so that the sealing effect is basically not influenced by operation torque, and the sealing reliability is obviously enhanced.

In one embodiment of the utility model, the interference between the circular arc sealing surface 9 and the sealing cone 16 varies according to the outer diameter of the connection pipe 1, preferably 0.15mm to 0.45mm. Several interference options are shown in table 1 below:

TABLE 1

As shown in fig. 1 to 6, in the first embodiment of the present utility model, the circular arc sealing surface 9 and the sealing cone 16 form a first clearance groove 17 for storing grease at a spacing, and the maximum groove width of the first clearance groove 17 is 0.4mm to 0.6mm.

The "groove width" refers to the width of the first clearance groove 17 in the radial direction.

With the above arrangement, the first clearance groove 17 can store the thread compound, and the circular arc sealing surface 9 and the sealing cone 16 can maintain good lubrication.

As shown in fig. 1 to 6, in the first embodiment of the present utility model, the petroleum pipe threaded joint further includes a storage groove structure provided between the threaded portion and the radial seal structure in the axial direction, the storage groove structure including: a cylindrical surface 3 provided on one of the connection pipe 1 and the coupling 5; a cylindrical hole 7 is formed on the other of the connection tube 1 and the coupling 5, and the cylindrical surface 3 and the cylindrical hole 7 define a second clearance groove 18 for storing grease.

In the above technical scheme, the cylindrical surface 3 is arranged on the connecting pipe 1, the cylindrical hole 7 is arranged on the coupling 5, and the second clearance groove 18 can store the thread compound, so that the circular arc sealing surface 9 and the sealing conical surface 16 can keep good lubrication.

In another embodiment of the present utility model, a cylindrical surface 3 may be provided on the coupling 5, and a cylindrical hole 7 may be provided on the connection tube 1.

In one embodiment of the present utility model, the second clearance groove 18 has a groove width of 0.3mm to 0.5mm. "groove width" refers to the width of the second clearance groove 18 in the radial direction.

The groove width is set in the range, and a better lubrication effect can be realized on the premise of not influencing the strength of the threaded joint.

In one embodiment of the utility model, the taper of the sealing cone 16 is 1:8 and the radius R of the circular arc sealing surface 9 is 45mm to 68mm.

As shown in fig. 1 to 6, in the first embodiment of the present utility model, an axial seal structure includes: an end portion 4 provided at one end of the connection pipe 1; a shoulder 8, provided on the collar 5; a first concave-convex structure provided on the end portion 4; the second concave-convex structure is arranged on the shoulder 8, and the second concave-convex structure is in concave-convex fit and interference fit with the first concave-convex structure.

In the technical scheme, the end part 4 and the shoulder 8 are in axial interference fit, the fastening torque can be borne, the first concave-convex structure and the second concave-convex structure are meshed with each other, the contact area of the end part 4 and the shoulder 8 is increased, and the torsion resistance of the petroleum pipe threaded joint can be enhanced. Like this, compare in prior art because of increasing the problem that the shoulder thickness caused sealed face thread gluing and because of reducing the problem that the shoulder thickness caused joint torsional property not enough, this scheme can improve sealing performance when guaranteeing torsional property.

Through the arrangement, the shoulder structure is optimized, the deformation rigidity of the shoulder is reduced, the contact area between the shoulder and the end plate is increased, and therefore the torsion resistance of the joint can be improved. The shoulder is of a concave-convex structure, so that the radial deformation rigidity of the shoulder is reduced, the contact area of the shoulder is increased, and the torsion resistance of the joint is obviously improved.

As shown in fig. 1 to 3, in the first embodiment of the present utility model, the first concave-convex structure includes a protrusion 10, a first horizontal side 11 and a groove 12 connected in sequence, the second concave-convex structure includes a shoulder groove 15, a second horizontal side 14 and a shoulder protrusion 13 connected in sequence, the protrusion 10 is in concave-convex fit with the shoulder groove 15, the shoulder protrusion 13 is in concave-convex fit with the groove 12, and the first horizontal side 11 and the second horizontal side 14 abut.

With the above arrangement, there is an axial interference fit between the projection 10 and the shoulder recess 15, and an axial interference fit between the recess 12 and the shoulder projection 13.

In one embodiment of the utility model, the interference between the first and second horizontal sides 11, 14 is 0.05mm to 0.1mm. In this way, the sealing performance is improved while the torsion resistance is ensured.

Example two

The second embodiment of the present utility model is different from the first embodiment only in the number and specific structure of the first concave-convex structure and the second concave-convex structure, and the remainder will not be described in detail.

As shown in fig. 4 to 6, in the second embodiment of the present utility model, the first concave-convex structure and the second concave-convex structure are plural, and the plural first concave-convex structures are sequentially connected in the radial direction, and the plural second concave-convex structures are sequentially connected in the radial direction; the first relief structure further comprises a groove bevel 19 connected to the groove 12, and the second relief structure further comprises a protrusion bevel 20 connected to the shoulder protrusion 13, the groove bevel 19 being in clearance fit with the protrusion bevel 20.

Through the arrangement, the first concave-convex structures and the second concave-convex structures are in one-to-one correspondence, and each first concave-convex structure is in concave-convex fit with the corresponding second concave-convex structure.

In one embodiment of the present utility model, the gap between the groove slope 19 and the protrusion slope 20 is 0.05mm to 0.15mm.

In the second embodiment of the present utility model, the slopes of the groove slope 19, the protrusion slope 20 and the sealing cone 16 are the same, so that the screwing between the connecting pipe 1 and the coupling 5 is facilitated.

From the above description, it can be seen that the above-described embodiments of the present utility model achieve the following technical effects: by arranging the circular arc sealing surface and the sealing conical surface, the petroleum pipe threaded joint has strong air sealing capability and high sealing reliability, and the sealing performance is slightly influenced by on-site buckling operation. After the connecting pipe and the coupling are screwed up, the circular arc sealing surface and the sealing conical surface are in interference fit in the radial direction to form metal/metal sealing, and the circular arc sealing surface and the sealing conical surface are tangent, namely in line contact.

It will be apparent that the embodiments described above are merely some, but not all, embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present utility model without making any inventive effort, shall fall within the scope of the present utility model.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.

The above description is only of the preferred embodiments of the present utility model and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (10)

1. Petroleum pipe threaded joint, its characterized in that includes threaded connection's connecting pipe (1) and coupling (5), along axial direction, connecting pipe (1) with be equipped with in proper order between coupling (5):

The thread part comprises an external thread (2) arranged on the connecting pipe (1) and an internal thread (6) arranged on the coupling (5);

The radial sealing structure comprises a tangential and interference fit arc sealing surface (9) and a sealing conical surface (16), wherein one of the arc sealing surface (9) and the sealing conical surface (16) is arranged on the connecting pipe (1), the other of the arc sealing surface (9) and the sealing conical surface (16) is arranged on the coupling (5), and the radial sealing structure is used for sealing a gap between the connecting pipe (1) and the coupling (5) in the radial direction;

And the axial sealing structure is used for sealing a gap between the connecting pipe (1) and the coupling (5) in the axial direction.

2. Petroleum pipe threaded joint according to claim 1, wherein the circular arc sealing surface (9) is arranged on the outer wall surface of the connecting pipe (1), the sealing conical surface (16) is arranged on the inner wall surface of the coupling (5), and a space is arranged between a tangent line between the circular arc sealing surface (9) and the sealing conical surface (16) and the axial sealing structure.

3. A petroleum pipe threaded joint according to claim 2, characterized in that the circular arc sealing surface (9) and the sealing cone (16) form a first clearance groove (17) for storing grease at the gap, the maximum groove width of the first clearance groove (17) being 0.4mm to 0.6mm.

4. The petroleum pipe threaded joint of claim 1, further comprising a storage groove structure disposed between the threaded portion and the radial seal structure in the axial direction, the storage groove structure comprising:

A cylindrical surface (3) provided on one of the connection pipe (1) and the collar (5);

And a cylindrical hole (7) which is formed on the other of the connecting pipe (1) and the coupling (5), wherein the cylindrical surface (3) and the cylindrical hole (7) define a second clearance groove (18) for storing lubricating grease.

5. A petroleum pipe threaded joint according to any of claims 1 to 4, characterized in that the distance L between the tangent line between the circular arc sealing surface (9) and the sealing cone (16) and the end face of the connecting pipe (1) protruding into the collar (5) is not less than 3.5mm; and/or the number of the groups of groups,

The taper of the sealing conical surface (16) is 1:8, and the arc radius R of the arc sealing surface (9) is 45mm to 68mm.

6. A petroleum pipe threaded joint according to any of claims 1 to 4, wherein the axial seal structure comprises:

an end part (4) arranged at one end of the connecting pipe (1);

A shoulder (8) provided on the collar (5);

A first relief structure provided on the end portion (4);

The second concave-convex structure is arranged on the shoulder (8), and the second concave-convex structure is in concave-convex fit and interference fit with the first concave-convex structure.

7. The petroleum pipe threaded joint according to claim 6, wherein the first concave-convex structure comprises a protrusion (10), a first horizontal side surface (11) and a groove (12) which are sequentially connected, the second concave-convex structure comprises a shoulder groove (15), a second horizontal side surface (14) and a shoulder protrusion (13) which are sequentially connected, the protrusion (10) is in concave-convex fit with the shoulder groove (15), the shoulder protrusion (13) is in concave-convex fit with the groove (12), and the first horizontal side surface (11) and the second horizontal side surface (14) are abutted.

8. A petroleum pipe threaded joint according to claim 7, characterized in that the interference between the first horizontal flank (11) and the second horizontal flank (14) is 0.05mm to 0.1mm.

9. The petroleum pipe threaded joint according to claim 7, wherein the first concave-convex structure and the second concave-convex structure are plural, and the plural first concave-convex structures are sequentially connected in a radial direction, and the plural second concave-convex structures are sequentially connected in the radial direction;

The first concave-convex structure further comprises a groove inclined surface (19) connected with the groove (12), the second concave-convex structure further comprises a convex inclined surface (20) connected with the shoulder convex (13), and the groove inclined surface (19) is in clearance fit with the convex inclined surface (20).

10. A petroleum pipe threaded joint according to claim 9, characterized in that the clearance between the groove chamfer (19) and the lug chamfer (20) is 0.05mm to 0.15mm; and/or the number of the groups of groups,

The slope of the groove slope (19), the slope of the convex slope (20) and the slope of the sealing conical surface (16) are the same.