GB2563676A

GB2563676A - Gripping collar and corresponding tubular joint

Info

Publication number: GB2563676A
Application number: GB1710110.6A
Authority: GB
Inventors: Thouvenot Jean; Burcker Patrick
Original assignee: Saint Gobain PAM SA
Current assignee: Saint Gobain PAM SA
Priority date: 2017-06-23
Filing date: 2017-06-23
Publication date: 2018-12-26
Anticipated expiration: 2037-06-23
Also published as: CN207906657U; GB2563676B; GB201710110D0

Abstract

This gripping collar (8) for a tubular connection of two tubular elements (4, 6) comprises a collar body (20), having a belt (22), sealing gasket (28) and a first gripping flange (24), and gripping means (30)t. The collar (8) comprises a first and second tooth (50; 52) for biting into the outer coating of each tubular in both tangential and axial directions when moved in a contact direction. The teeth are electrically connected to provide electrical connection between each tubular. There is also a second flange 26 and the gripping means, also for moving the teeth, may be a screw 36 and nut 38. The teeth may be formed on the nut or flange.

Description

Gripping collar and corresponding tubular joint

The present invention relates to a gripping collar for a tubular connection of two tubular elements with a plain end-piece of the type comprising: - a collar body, having a belt and a first gripping flange, - means for gripping the belt, the collar body extending around a central axis, the gripping collar comprising: - a first tooth suitable for biting into a first of the two tubular elements, - a second tooth suitable for biting into a second of the two tubular elements, the first tooth and the second tooth being electrically connected, and - means for moving the first tooth and the second tooth. A gripping collar is known from document GB 2,305,481 comprising metal segments having several radial protrusions intended to bite into the outer surface of assembled pipes. These protrusions have a flat apex and are subject only to a radial force during gripping of the two half-segments.

When the pipes are provided with an organic outer coating, the protrusions crush the coating without traversing it, and thus do not provide electrical continuity. GB 2,450,686 describes an assembly collar comprising a clip intended to provide electrical continuity between two pipes with a plain end-piece and a fitting end. This clip includes a deformable tongue that is folded down on the outer surface of the plain end-piece of one of the pipes in order to ensure electrical continuity. Such a solution is costly and difficult, since it requires manually adding a specific additional piece during mounting of the line. A collar for a tubular connection is also known from document FR 2,922,611.

The invention aims to propose a gripping collar providing an electrical connection between two tubular elements, with cost-effective and reliable means.

To that end, the invention relates to a gripping collar of the aforementioned type, characterized in that the movement means are suitable for moving the first tooth and the second tooth in a contact direction having a tangential component, oriented tangentially relative to the central axis, and a radial component, oriented radially relative to the central axis.

According to specific embodiments, the gripping collar according to the invention ay include one or more of the following features: - the tangential component is larger than the radial component, in particular over the entire movement distance of the first tooth and the second tooth, between a state out of contact and a state in contact; - at least one of the first and second teeth is positioned on the first gripping flange, in particular the first and second teeth are positioned on the first gripping flange; - the or each tooth positioned on the first gripping flange is made in a single piece with this first gripping flange; - the gripping means comprise a gripping member, in particular a screw, and a complementary gripping member, in particular a nut; - at least the first tooth is positioned on the complementary gripping member, preferably the first and second teeth are positioned on the complementary gripping member; - the or each tooth positioned on the complementary gripping member is made in a single piece with the complementary gripping member; and - the gripping collar comprises a second gripping flange and at least one of the first and second teeth is positioned on the second gripping flange.

The invention also relates to a tubular joint, of the type comprising two tubular elements with a plain end-piece and a gripping collar, characterized in that the gripping collar is a gripping collar as defined above.

According to one particular embodiment, the tubular joint may include the following feature: - the two tubular elements include a base body and an outer coating, and each of the teeth is suitable for traversing the outer coating of the associated tubular element and coming into contact with the base body.

The invention will be better understood upon reading the following description, provided solely as an example and done in reference to the appended drawings, in which: - figure 1 is a perspective view of a tubular joint comprising a gripping collar according to a first embodiment of the invention; - figure 2 is an enlarged view of detail II of figure 1; - figure 3 is a schematic cross-section of a tubular element and a tooth in two different operating configurations of the gripping collar; - figure 4 is a perspective view of a tubular joint comprising a gripping collar according to a second embodiment of the invention; and - figure 5 is an enlarged view of detail V of figure 4.

Figure 1 shows a tubular joint according to a first embodiment of the invention, designated by general reference 2.

The tubular joint 2 comprises two tubular elements, namely a first tubular element 4 and a second tubular element 6. The tubular joint 2 is provided with a gripping collar 8.

Each of the first element 4 and the second tubular element 6 comprises a plain end-piece 10, 12 at its end. The plain end-pieces 10 and 12 are surrounded by the gripping collar 8 and are connected to one another sealably by this gripping collar 8. The gripping collar 8 is therefore suitable for connecting the two tubular elements 4 and 6. The tubular elements 4 and 6 extend around a central axis A-A, B-B, respectively, which in the case at hand are coaxial.

Each of the first tubular element 4 and second tubular element 6 has a base body 14 made from an electrically conductive material, such as metal, in particular cast-iron, and an outer coating 16. The outer coating 16 is for example made from a material that is not electrically conductive, such as plastic, for example an epoxy resin, acrylic or polyurethane.

The gripping collar 8 includes a collar body 20 having a belt 22 and a first gripping flange 24. The gripping collar 8 also comprises a second gripping flange 26.

The collar body 20 extends around a central axis X-X, which is, in the installed state, coaxial to the axes A-A and B-B of the tubular elements 4, 6.

The collar body 20 is advantageously provided with a through axial slit, thus defining two circumferential ends that may or may not overlap. The first and second gripping flanges 24, 26 are each fastened near a circumferential end of the collar body 20.

The belt 22 is made from metal, preferably steel. One or both gripping flanges 24, 26 is/are also made from metal, in particular steel. One or both gripping flanges 24, 26 is/are fastened or connected to the belt 22, in particular by welding, so as to tighten the belt 22 around the tubular elements during gripping.

In an alternative that is not shown, the gripping collar 20 can be made in several segments connected to one another by gripping flanges as described above.

The belt 22 is profiled and forms a hollow annular space.

The gripping collar 8 comprises a sealing gasket 28 made from an elastic material positioned inside the hollow annular space of the belt 22.

The gripping collar 8 is provided with gripping means 30 of the belt 22. The gripping means 30 are suitable for bringing the belt 22 from a released configuration, in which the belt 22 has a diameter allowing the insertion of both tubular elements 4, 6 with a plain end-piece into the belt, to a gripping configuration in which both tubular elements 4, 6 are held by the sealing gasket 28 and the belt 22 is gripped against these tubular elements.

The gripping means 30 comprise a gripping member 36, in the case at hand a screw, and a complementary gripping member 38, in the case at hand a nut. The gripping member 36 and the complementary gripping member 38 are suitable for bringing the gripping flanges 24 and 26 closer to one another in order to bring the belt 22 into the gripping configuration and to separate the gripping flanges 24 and 26 from one another in order to bring the belt 22 into the released configuration.

Alternatively, other gripping members and complementary gripping members can be used.

The gripping collar 8 also comprises a first tooth 50 suitable for biting into the surface of the first tubular element 4 and a second tooth 52 suitable for biting into the surface of the second tubular element 6. The first tooth 50 and the second tooth 52 are electrically connected.

Advantageously, the first tooth 50 and the second tooth 52 are positioned on the first gripping flange 24 and are made in a single piece with this gripping flange 24. Advantageously, the first gripping flange 24 and the first tooth 50 and/or the second tooth 52 are made in a single piece, for example by stamping. The gripping flange 24, the first tooth 50 and the second tooth 52 are made from metal, in particular from steel.

The gripping collar 8 also comprises means 54 for moving the first tooth 50 and the second tooth 52. These movement means 54 are suitable for moving the first tooth 50 and the second tooth 52 in a contact direction DC (see figure 3). The contact direction DC has a tangential component DT oriented tangentially relative to the central axis X-X and a radial component DR oriented radially relative to the central axis X-X. The tangential component DT is oriented tangentially relative to a cylinder with a circular section with axis X-X and extends in a plane perpendicular to the central axis X-X. Furthermore, the tangential DT and radial DR components are oriented perpendicular to one another. The tangential component DT is also tangential with respect to an outer surface of the tubular elements 4 and 6 into which the respective tooth 50, 52 bites.

The radial component DR is oriented radially with respect to the central axis X-X. Thus, during the movement of the teeth 50, 52 by the movement means 54, the surface of the tubular element 4, 6 in contact with the respective tooth 50, 52 is subject to an incision by the teeth that makes it easy to traverse any outer coating 16 and allows the tooth 52, 50 at least to come into contact with the metal base body 14 of the associated tubular element 4, 6.

More advantageously, the tangential component DT is larger than the radial component DR, in particular over the entire movement distance DP of the first tooth 50 and/or the second tooth 52 between a state out of contact, in which the teeth 50, 52 do not come into contact with the base body 14 of the tubular elements, and a state in contact, in which the teeth 50, 52 are in contact with the base body 14 of the tubular elements. In other words, the contact direction DC includes an angle of more than 45° and less than 90° with the radial direction DR oriented toward the axis X-X.

This is shown in figure 3, which on the one hand shows the base body 14 and the outer coating 16 of the first or second tubular element 4 or 6, and on the other hand schematically shows one of the two teeth 52 or 50. The tooth 50, 52 is shown once in the state out of contact and once in the state in contact. In the out of contact state, the tooth 50 or 52 extends exclusively outside the base body 14 of the tubular element 4 or 6 and is not in contact with the base body 14. In the in contact state, the tooth 50 or 52 has traversed the outer coating 16 and is in pronounced contact with the base body 14 of the respective tubular element 4 or 6 and, if applicable, bites into the base body 14 thereof.

In the present case, the movement means 54 are formed by the gripping means 30 and therefore comprise the same elements. The teeth 50, 52 are therefore brought into the contact state during gripping of the belt 22 around the tubular elements.

The gripping collar 8 works as follows.

The gripping collar 8 is initially in the released configuration.

First of all, the tubular elements 4 and 6 are inserted on either side in the belt 22 and in the sealing gasket 28.

Next, the gripping means 30 are gripped, thus moving the belt 22 into the gripping configuration. At the same time, the gripping flanges 24, 26 are moved toward one another and the teeth 50, 52 bite into the tubular elements 4, 6.

When the belt 22 reaches the gripping configuration, the teeth 50, 52 reach the contact state in which they have traversed the outer coating 16 and are in contact with the base body 14 of the tubular elements.

Thus, the electrical connection between the tubular elements 4 and 6 is established reliably and without requiring a manipulation other than the gripping of the gripping means.

In alternatives that are not shown, the first and second teeth 50, 52 can be positioned on the second gripping flange 26, or on both gripping flanges 24 and 26 at the same time, or the first tooth is fastened on the first gripping flange 24 and the second tooth is fastened on the second gripping flange 26, with, in all three cases, an operating mode similar to that described above in reference to figures 1 to 3.

Figures 4 and 5 show a second embodiment of a tubular joint including a gripping collar according to the invention.

Subsequently, only the differences with respect to the first embodiment will be explained. Similar elements bear the same references.

The first gripping flange 24 does not include teeth 50, 52.

The complementary gripping member 38 is provided with the first tooth 50. In the case at hand, the complementary gripping member 38 is provided with first and second teeth 50, 52.

The complementary gripping member 38 is a nut having two branches 70, 72, each of the first and second teeth 50, 52 protruding from one of these branches 70, 72. The complementary gripping member 38 is manufactured from an electrically conductive material, in particular metal, such as steel.

The first and second teeth 50, 52 are made in a single piece with the complementary gripping member 38, in particular as one part.

The tubular joint 2 of this second embodiment does not include teeth positioned on the second gripping flange 26. However, alternatively, teeth may also be positioned on the second gripping flange 26.

This second embodiment is advantageous, given that it makes it possible to equip existing gripping collars with means for establishing an electrical connection according to the invention without it being necessary to modify the gripping flanges 24, 26.

The tubular joints and the gripping collar according to the invention make it possible to reliably establish an electrical connection between the two tubular elements 4 and 6, given that the teeth move in a contact direction having tangential and radial components during gripping. Furthermore, the manufacturing of the gripping collar is cost-effective, given that the teeth are either supported by the gripping flanges or by the complementary gripping member.

The elements that have been described above in connection with other elements can be used individually with the relevant embodiment in all technically possible combinations. The description of a combination of several elements therefore must not be interpreted as meaning that only the combination of elements taken together is considered.

Claims

1. - A gripping collar (8) for a tubular connection of two tubular elements (4, 6) with a plain end-piece of the type comprising: - a collar body (20), having a belt (22) and a first gripping flange (24), - means (30) for gripping the belt, - the collar body extending around a central axis (X-X), the gripping collar (8) comprising: - a first tooth (50) suitable for biting into a first of the two tubular elements, - a second tooth (52) suitable for biting into a second of the two tubular elements, the first tooth and the second tooth being electrically connected, and - means (54) for moving the first tooth and the second tooth, characterized in that the movement means (54) are suitable for moving the first tooth and the second tooth in a contact direction (DC) having a tangential component (DT), oriented tangentially relative to the central axis, and a radial component (DR), oriented radially relative to the central axis.

2. - The gripping collar according to claim 1, wherein the tangential component is larger than the radial component, in particular over the entire movement distance of the first tooth and the second tooth, between a state out of contact and a state in contact.

3. - The gripping collar according to claim 1 or 2, wherein at least one of the first and second teeth (50, 52) is positioned on the first gripping flange (24), in particular the first and second teeth are positioned on the first gripping flange.

4. - The gripping collar according to claim 3, wherein the or each tooth positioned on the first gripping flange (24) is made in a single piece with this first gripping flange.

5. - The gripping collar according to any one of the preceding claims, wherein - the gripping means (30) comprise a gripping member (36), in particular a screw, and a complementary gripping member (38), in particular a nut.

6. - The gripping collar according to claim 1 or 2 and claim 5 considered together, wherein at least the first tooth (50) is positioned on the complementary gripping member, preferably the first and second teeth (50, 52) are positioned on the complementary gripping member.

7. - The gripping collar according to claim 6, wherein the or each tooth (50, 52) positioned on the complementary gripping member (38) is made in a single piece with the complementary gripping member.

8. - The gripping collar according to claim 1 or 2, wherein the gripping collar comprises: - a second gripping flange (26), and wherein - at least one of the first and second teeth (50, 52) is positioned on the second gripping flange (26).

9. - A tubular joint, of the type comprising two tubular elements (4, 6) with a plain end-piece and a gripping collar, characterized in that the gripping collar is a gripping collar according to any one of the preceding claims.

10. - The tubular joint according to claim 9, wherein the two tubular elements include a base body (14) and an outer coating (16), and each of the teeth (50, 52) is suitable for traversing the outer coating (16) of the associated tubular element (4, 6) and coming into contact with the base body (14).