NO344715B1

NO344715B1 - A swivel coupling, a swivel coupling system, and a method for preventing a swivel coupling from rotating

Info

Publication number: NO344715B1
Application number: NO20181661A
Authority: NO
Inventors: Nils-Per Sjåstad
Original assignee: Stadpipe As
Priority date: 2018-12-20
Filing date: 2018-12-20
Publication date: 2020-03-23
Also published as: NO20181661A1

Description

TITLE:

Pipe Coupling

Field of the invention

The present invention relates to a female swivel coupling for forming a swivel coupling between two pipes, a male swivel coupling for forming a swivel coupling between two pipes, a swivel coupling system, and a method for preventing a swivel coupling from rotating.

Background and objects of the invention.

When installing and maintaining pipes in diverse technical structures, such as for aquaculture, water treatment or on-board vessels, standard pipes and couplings therefor are generally used. These have standard sizes in order to be easily exchangeable and maintained. Often they are mounted in place and not changed, but for many application a more dynamic layout is desired. Then a coupling that can be turned, so that the layout can be changed, while the pipe is under pressure (for instance while filled with water or other liquids or fluids under pressure) would be very useful. At the same time, such a coupling should ideally be able to be exchanged for a standard coupling, in order for upgrades/changes to already existing systems to be carried out in the most efficient way. It is the aim of the present invention to bring forth such a pipe coupling fitting with existing couplings and pipes and yet being able to be rotated while under pressure.

Disclosure of the state of art.

When one pipe can rotate with respect to another pipe at the jointing of these two pipes it is often called a swivel joint. There are several different types of swivel joints that are commonly used. One such device uses bearings. The inner pipe coupling has bearings along the outside of it; which usually fit into grooves on the inside of the outer pipe. These bearings allow the inner pipe to rotate without the outer pipe. This can be found in variations of single and multiple rows of bearings. Another solution use flanges that can rotate. In these devices, after the flanges are bolted together, the two pipes are held in place. Since the pipes can rotate within the flanges, the two pipes can rotate but are still held in a fluid tight connection.

Sometimes, a special device is placed between the two pipes that can rotate in the axial direction. Since both pipes are connected to different ends of the device, the two pipes can rotate with respect to each other. Yet another solution uses specialized shapes on the end of one or more of the pipes. A ball and socket type joint is the most commonly used in this type of joint. The inner pipe is usually shaped at least partially spherical, while the outer pipe is arranged to receive this shape. Sometimes these pipes are connected together by flanges and sometimes the ends themselves hold the pipes together.

These are but a few of the broad types of solutions to the problem of allowing one pipe to rotate axially with respect to another.

The state of the art is also described in CN2570586Y, GB842201A, US6419279B1 and DE3444930A1.

Summary of the invention

A male swivel coupling for forming a swivel coupling between two pipes is characterized in that it is adapted to fit inside a female coupling, wherin the female swivel coupling comprises: a female lip on one end, a female pipe connection area, on the other, and a male contact area between the two; wherein: a female contact diameter is defined as the largest inner diameter of the male coupling and is located between the female contact area and the end of the female lip; and thereby forming a coupling socket between the female lip and the female contact area, wherin the male swivel coupling comprises: a male contact area on one end, a male pipe connection area on the other end, and a male shoulder between the two; wherein: the distance between the female contact area and the end of the female lip is larger than the distance between the male contact area and the male shoulder; and thereby forming a swivel gap in the space above the male shoulder and below the end of the female lip.

In accordance with a preferred embodiment of the male coupling it comprises a sealer to prevent fluid leakage between the male coupling and the female coupling when in operation. More preferably the sealer extends radially at least partially around the outside of the male coupling between the male shoulder and the male contact area. Even more preferably the sealer is an O-ring located within a sealer groove extending radially around the male coupling.

In accordance with another preferred embodiment of the male coupling there is a friction reducing coating on the male contact area and/or the female contact area.

The swivel coupling system according to the present invention is characterized in that it comprises: a first coupling which is a male coupling as described above, a second coupling that is a female coupling; an attachment means, preferably a plurality of bolts and a first and second flange; wherein the attachment means is used to hold the male coupling to the second coupling.

In accordance with a preferred embodiment of the swivel coupling system according to the present invention it comprises a gasket located between the male contact area and the second coupling contact area.

In accordance with another preferred embodiment of the swivel coupling system the second coupling of the system is a female coupling and further a sealer located radially, preferably an O-ring within a sealer groove on the male coupling at least partially between the male contact area and the end of the female lip.

In accordance with another preferred embodiment of the swivel coupling system the second coupling is a female coupling and the gasket has a thickness that is at least the height of the swivel gap.

In accordance with another preferred embodiment of the swivel coupling system the male coupling resides within the coupling socket such that the male contact area is in rotatable contact with the female contact area.

The method according to the present invention is characterized in that it comprises the steps of: a) obtaining a first coupling which is a male coupling according to the present invention, b) obtaining a second coupling that is a female coupling according to the present invention, c) inserting a gasket between the male contact area and the second coupling contact area; and d) using an attachment means, preferably a plurality of bolts and a first and second flange; to hold the male coupling and the second coupling together.

In accordance with a preferred embodiment of the method the second coupling of step b) is a female coupling and the gasket of step c) has a thickness at least as large as the height of the swivel gap.

Description of the figures

Embodiments of the present invention will now be described, by way of example only, with reference to the following diagrams wherein:

FIG 1A shows a cross section of a standard pipe coupling.

FIG 1B shows a perspective view of a standard pipe coupling.

FIG 2A shows a cross section view of the present invention with pipes and flanges. FIG 2B shows a cross section view of the present invention with flanges.

FIG 2C shows a perspective view of the present invention with flanges.

FIG 2D shows a cross section close up view of part of the present invention with flanges.

FIG 3A shows a cross section view of the male coupling.

FIG 3B shows a perspective view of the male coupling.

FIG 4A shows a cross section view of the female coupling.

FIG 4B shows a perspective view of the female coupling.

FIG 5A shows a cross section view of the present invention.

FIG 5B shows a perspective view of the present invention

FIG 5C is a close up cross section view of the present invention.

FIG 6 is a cross section view of an alternate embodiment of the present invention. FIG 7A is a cross section view of an alternate embodiment of the present invention. FIG 7B is a perspective view of an alternate embodiment of the present invention.

Reference numbers and the corresponding annotations

10 Male Coupling

11 Male Shoulder

12 Male Contact Area

13 Sealer Groove

131 Sealer

14 Male Pipe Connection Area

15 Male Contact Diameter

20 Female Coupling

21 Female Shoulder

22 Female Contact Area

23 Female Lip

24 Female Pipe Connection Area

25 Female Contact Diameter

30 Swivel Gap

31 Coupling Socket

40 Gasket

50 Bolts

51 Flange

510 Female Flange

520 Male Flange

60 Standard Coupling

61 Standard Pipe Connection Area

62 Standard Contact Area

70 Pipe

Description of preferred embodiments of the invention

Using the attached drawings, the technical contents, and detailed descriptions, the present invention is described. Alternate embodiments will also be presented.

This invention is a swivel pipe coupling to connect two pipes together in such a way that it is still possible for the coupling to rotate. It consists of two parts: a male coupling and a female coupling. When these parts are fastened together, usually using the industrial standard flanges and bolts, there is a swivel gap. It is this gap that allows for the present invention to allow the swivel pipe coupling to rotate even when under pressure. Both the male coupling and the female coupling are hollow to allow for fluid to flow through the pipes.

FIGs 1A and 1B show known art; a standard way in which two pipes are coupled together. Two standard couplings 60 are placed so that each standard contact area 62 are in contact. The standard contact areas 62 are flat. The standard couplings 60 are held together by standard flanges 51 around each of the standard couplings 60 and bolts 50 through the flanges. This is a standard practice in the industry. Pipes 70 are connected to standard coupling 60 at the standard pipe connection area 61. It is common for a gasket 40 to be located between the two standard contact areas 62 in order to avoid leakage.

By standard, we mean industry standard. Such couplings, with flanges and bolts, are made in various standard sizes/dimensions, so as to fit together and be interchangeable. Although the couplings of the present invention could of course be made in any dimensions, it is an advantage it they can fit together with standard parts, and thus it is preferable to make them in dimensions that will fit the standard sized flanges and pipes. Therefore the ends of the couplings where the pipes are threaded on should be dimensioned to receive standard pipe sizes, and the outer diameters of the coupling parts should fit the inner diameters of standard flanges, and the height of the couplings when put together (i.e. space between flanges) should ideally be so that standard bolts can be used to lock the flanges and couplings together.

FIGs 2A – 2D show the present invention. Unlike in the standard coupling 60 case, the present invention uses two different shaped couplings, which we will refer to herein as female and male couplings. FIG 2A shows how the present invention is used with pipes. FIG 2B shows a close up of the swivel coupling without pipes shown, and FIG 2C shows a perspective view of the present invention. FIG 2D is a close up of a portion of the present invention.

A pipe 70 is connected to the female coupling 20 at the female pipe connection area 24. The female contact area 22 is located on the opposite end as the pipe connection area 24. The female lip 23 extends longitudinally from the female contact area. In the same way, a different pipe 70 is connected to the male coupling 10 at the male pipe connection area 14. The male contact area 12 is located on the opposite end as the pipe connection area 14. The female contact area 22 and the male contact area 12 are in rotatable contact. The rotation is possible because there is a swivel gap 30 between the female flange 520 and the male flange 510. Bolts 50 are used to keep the female coupling 20 and the male coupling 10 together by passing through the flanges in a standard manner. The female coupling 20 is in effect locked in place between the flanges 510 and 520, while the male coupling 10 due to the swivel gap 30 has enough of a playroom between the male flange 510 and the female contact area 22 that it can move in respect thereto. Thus the male coupling is rotatable in relation to the flanges and the female coupling, and any pipe connected to the male coupling can be rotated. Therefore any side-pipes or outtakes etc. coming off the pipe connected to the male coupling can be moved by rotating the male coupling.

The outer diameter between the female shoulder 21 and the end of the female lip 23 is a constant that is larger than the inner diameter of the female contact area 24. In such a way the end of the female coupling 20 flares out so that flanges 510/520 may be used to secure the female coupling 20 and the male coupling 10 together. The female flange 520 rests upon the female shoulder 21 and a male flange 510 rests upon the end of the female lip 23. Note that these flanges are the same; it is their positions on the present invention that is being referenced.

The largest diameter of the male coupling 10 is located between the male shoulder 11 and the male contact area 12. This is a constant that is the same, or nearly the same, as the diameter of the female contact area 22. On figure 3A this diameter of the male coupling is shown as reference 15, while in figure 4A the corresponding diameter of the female contact area is shown as reference 25. Thus 15 and 25 should be close to the same diameter length for a male and female coupling meant to be paired together, and the female diameter 25 cannot be larger than the male diameter 15 for a proper fit. In this way, the male 10 coupling rests within the female coupling 20. It is important that the male coupling 10 has space to rotate inside of the female coupling 20.

The swivel gap 30 is formed because there is gap formed between the male flange 510 and the male shoulder 11. This occurs because the female lip 23 extends past the male shoulder 11 when the male contact are 12 is in contact with the female contact area 22. This means that the male flange 510 rests upon the end of the female lip 23.

Located upon the male coupling 10 in the preferred embodiment is a sealer groove 13. This groove 13 is located on a surface of the male coupling 10 in contact with the female coupling 20. The location of the groove 13 would preferably be as shown in figures 3A and 5A, on the outside of the male shoulder so that the grove faces the female lip 23. Within this groove a sealer 131 is inserted. The sealer is designed to reduce or prevent fluid loss in the present invention when under pressure. The sealer is preferably an O-ring. The combination of the diameters 15 and 25 being close to the same, and the use of the sealer, will effectively seal and prevent leakage, at the same time as movement/rotation of the male coupling is still allowed due to the swivel gap 30. This can be best seen in figure 2D.

The grove 13 with sealer 131 is a preferred embodiment, but not strictly needed. As long as the diameters 15 and 25 are close to the same, the couplings will seal. The larger the differences between the diameters (with 15 as explained needing to be smaller than 25) the more of a need for a grove with sealer will be in order for the seal to hold.

In an alternative embodiment the grove 13 with sealer 131 could be placed on the inside of the female lip 23 facing the male shoulder, i.e. at close to the same location/contact point between couplings, but moved from the male coupling 10 to the female coupling 20. This would function very similarly.

Other kinds of sealers than O-rings could of course be used, and should be adapted to the specific types of pipes and fluids. For instance sealing coatings could be employed. The O-ring could also instead of resting within a grove 13 just sit on the outside of the male shoulder (which would have to have a smaller diameter 15 to make up for this), but this would not be ideal, as it would make turning of the male coupling in relation to the female coupling more difficult, and the O-ring would be more likely to not stay in place properly.

It is also possible to use coatings on the male contact area 12 and/or the female contact area 22, and on the outside of the male shoulder 11 and/or inside of the female lip 23 contacting said female shoulder 11, to reduce friction and thus help the female coupling 20 and female coupling 10 to better slide against each other, thus improving the turning movement of the male coupling 10 in relation to the female coupling 20 and the flanges 51. Such coatings could be any coating suitable for the purpose, such as oil or silicone based lubricants, and is well known in the field.

The pipe couplings according to the present invention thus utilize standard flanges and bolts, in order to be coupled to pipes and parts of standard dimensions. It can be provided in plastic, such as PEH 100, which is commonly used for pipe couplings, or in other desired and suitable materials such as metals.

FIGs 3A and 3B show the male coupling 10. As mentioned previously the male coupling 10 has a male pipe connection area 14 at one end and a male contact area 12 at the other. It is the male contact area 12 that will be in the contact with the female coupling 20 (not shown) at the female contact area 22 (not shown).

The male contact diameter 15 is the diameter of the male contact area 12. The male coupling 10 will have this diameter between the male contact area 12 and the male shoulder 11. This will make the male coupling 10 flare out at this end. In the preferred embodiment, the male coupling 10 will have a sealer groove 13.

FIGs 4A and 4B show the female coupling. As mentioned previously the female coupling 20 has a female pipe connection area 24 at one end and a female contact area 22 at the other. It is the male contact area 12 (not shown) that will be in the contact with the female coupling 20 at the female contact area 22.

The male contact diameter 25 is the diameter of the female contact area 22. The female coupling 20 will have this diameter between the female contact area 22 and the end of the female lip 23. This will form a coupling socket 31 where to male coupling 10 (not shown) can fit. It is at the female shoulder 21 where the female coupling 20 begins to flare out and gives the female flange 520 (not shown) a place to rest.

FIGs 5A – 5C shows the present invention with a female and male coupling. The female flange 520 and the male flange 510 are not shown, as they are just methods of attaching the female coupling 20 to the male coupling 10. Such flanges are standard use for holding together couplings. The reference numbers are the same in these figures as in FIGS 2A – 2D. These descriptions will not be repeated. Please note that the total with/outer diameter of the female coupling, as shown in figure 5A from the outside of the female lip 23 on one side to the other, is preferably the same as the diameters of standard couplings. Thus, the flanges can also be standard, with holes for bolts located just on the outside of the female lip, as shown in figure 2B. This in turn means that the diameter of the male coupling 15 is preferably less than the standard diameter of standard couplings, as it fits inside the female coupling. The figure shows how the male coupling 10 sits in the coupling socket 31 formed by the constant inner diameter of the female coupling 20 between the female contact area 22 and the end of the female lip 23.

FIG 6 shows a system that uses an embodiment of the present invention. This is a system that prevents the swivel coupling from rotating. It is not always desirable for a pipe coupling to rotate. One solution would be to remove the female coupling 20 and the male coupling 10 from the pipes 70 and attach a pair of standard couplings 60 instead. However, it is possible to stop the male coupling 10 from rotating within the female coupling 20. This is done by inserting a gasket 40 between the male contact area 12 and the female contact area 22. The gasket 40 needs to be at least as thick as the swivel gap 30. The swivel gap 30 cannot be shown FIG 6 but is the same as defined and shown previously. This causes the male shoulder to be located at the same level as, or extend beyond, the female lip 23, since the gasket 40 pushes it away from the female coupling. In that way when the male coupling 10 and the female coupling 20 are connected together, the female flange 520 (not shown) will rest upon the female shoulder 21 and the male flange 510 (not shown) will rest upon male shoulder 11. Without the gasket 40 there would be a swivel gap 30 and the male coupling 10 could rotate within the female coupling 20. With the gasket 40 and the flanges and bolts in place, the pressure applied to the couplings from the bolted flanges will keep the male coupling from turning. Note that the male coupling 10 is located partly within the coupling socket 31.

FIGs 7A and 7B show a system that uses an embodiment of the present invention. In this embodiment the rotation is also stopped. The system uses a standard coupling 60 and a male coupling 10. This need may arise when it is easier to remove the female coupling 20 instead of using the system of FIG 6. This could be because there is an existing pipe 70 with a standard coupling 60 or for other operational concerns. In this case, a gasket 40 is inserted between the standard contact area 62 and the male contact area 12 in order to prevent rotation.

A special note must be made for how the couplings between the different sections of pipe of held together (e.g. between the female coupling 20 and the male coupling 10). There is a wide range of attachment means that are suitable. The figures show the attachment means as a system of flanges 51, 510, 520 and a plurality of bolts 50. This is a very common way of holding two pipes together in the industry and the preferred attachment means for this invention. The attachment means between the female coupling 20 and the male coupling 10 should allow for the rotation of the male coupling 10 within the female coupling 20 when the distance between the male contact area 12 and the male shoulder 11 is less than the distance between the female contact area 22 and the end of the female lip 23. While flanges are an easy way to achieve this, another option is a clamp or sleeve that sits on the female lip 23 on one side and the female shoulder 21 on the other.

In the situation where it is desirable that the coupling between the two pipes does not rotate (as shown in figures 6, 7A, and 7B), the attachment means can include the means that allow rotatable connection mentioned previously. It can also include additional means. These include ways to permanently affix the two couplings together. Examples of this include welding, devices that fill the swivel gap before clamping or bolt, things that lift the male shoulder 11 even with or past the end of the female lip 23, or sleeves that go around both sides of the coupling. Another option are systems where friction couplings are used, or welded to the outside of the coupling that prevent rotation.

Several other attachment means for both a rotatable joint and a non-rotatable between two pipe couplings will present themselves to one skilled in the art.

Claims

PATENTCLAIMS

1. A male swivel coupling (10) for forming a swivel coupling between two pipes, where said male swivel coupling is adapted to fit inside a female coupling (20),

wherin the female swivel coupling (20) comprises:

a female lip (23) on one end, a female pipe connection area (24), on the other, and a female contact area (22) between the two; wherein:

a female contact diameter (25) is defined as the largest inner diameter of the female coupling (20) and is located between the female contact area (22) and the end of the female lip (23); and thereby

forming a coupling socket (31) between the female lip (23) and the female contact area (22),

wherin the male swivel coupling comprises:

a male contact area (12) on one end, a male pipe connection area (14) on the other end, and a male shoulder (11) between the two; characterized in that

the distance between the female contact area (22) and the end of the female lip (23) is larger than the distance between the male contact area (12) and the male shoulder (11); and thereby

forming a swivel gap (30) in the space between the male shoulder (11) and the end of the female lip (23).

2. The male swivel coupling (10) according to claim 1, characterized in that the male coupling (10) further comprises a sealer (131) to prevent fluid leakage between the male coupling (10) and the female coupling (20) when in operation.

3. The male swivel coupling (10) according to claim 2, characterized in that the sealer (131) extends radially at least partially around the outside of the male coupling (10) between the male shoulder (11) and the male contact area (12).

4. The male swivel coupling (10) according to claim 3, characterized in that the sealer (131) is an O-ring located within a sealer groove (13) extending radially around the male coupling (10).

5. The male swivel coupling according to any one or more of the previous claims, characterized in that there is a friction reducing coating on the male contact area (12) and/or the female contact area (22).

6. A swivel coupling system, characterized in that it comprises:

a) a first coupling which is a male coupling (10) according to one or more of claims 1 to 5;

b) a second coupling that is a female coupling (20) according to claim 1; c) an attachment means, preferably a plurality of bolts (50) and a first and second flange (51);

wherein the attachment means is used to hold the male coupling (10) to the second coupling (20).

7. The swivel coupling system according to claim 6, characterized in that it further comprises a gasket (40) located between the male contact area (12) and the second coupling contact area (22),(62).

8.The swivel coupling system according to claim 6 or 7, characterized in that in that the second coupling of the system is a female coupling (20) and further a sealer (131) located radially, preferably an O-ring within a sealer groove (13) on the male coupling (10) at least partially between the male contact area (12) and the end of the female lip (23).

9. The swivel coupling system according to one or more of claims 6 to 8, characterized in that the second coupling is a female coupling (20) and the gasket (40) has a thickness that is at least the height of the swivel gap (30).

10. The swivel coupling system according to one or more of claims 6 to 9, characterized in that the female coupling (10) resides within the coupling socket (31) such that the male contact area (12) is in rotatable contact with the female contact area (22).

11. A method for preventing a swivel coupling from rotating, characterized in that it comprises the steps of:

a) obtaining a first coupling which is a male coupling (10) according to one or more of claims 1 to 5;

b) obtaining a second coupling that is a female coupling (20) according to claim 1;

c) inserting a gasket (40) between the male contact area (11) and the second coupling contact area (21),(61); and

d) using an attachment means, preferably a plurality of bolts (50) and a first and second flange (51); to hold the male coupling (10) and the second coupling (20),(60) together.

12. The method for preventing a swivel coupling from rotating according to the previous claim, characterized in that the second coupling of step b) is a female coupling and the gasket (40) of step c) has a thickness at least as large as the height of the swivel gap (30).