FR2909742A1 - Flange-to-flange type pipe e.g. hot gas conduit, connection system sealing device for e.g. chimney, has grid maintaining sealing strip along rigid spacer, and bolt maintaining sealing joint between lower flange and upper flange - Google Patents

Abstract

The device has a sealing strip (15) and a rigid spacer (12) intercalated between a lower flange (3) and an upper flange (4) of a pipe connection system, where the strip is made of fabric e.g. fiber or woven web. A grid (13) maintains the sealing strip along the spacer. A bolt (16) maintains a sealing joint (11) between the lower flange and the upper flange. The grid has a width higher than that of the spacer, and is arranged between the lower flange and the spacer. The grid and the spacer are made of stainless steel.

Description

1 Waterproof device for an assembly of flange type connections to

  The invention relates to the field of sealing devices used for flanged flange-type piping connection systems, in particular hot gas ducts such as chimneys or pipes used in fumigation. . Conventionally, the assemblies of the hot gas pipes are made by connecting flanges. The rigidity of such a connection system is provided by bolts, and sealing is guaranteed by welds made between the ends of the flanges at the bolts. However, this type of embodiment requires long grinding of the sealing welds when it is desired to disassemble the connecting flanges, which inevitably causes the destruction of the bolts.

  The invention aims to provide a solution to this problem. An object of the invention is therefore to provide a device that while ensuring the rigidity and tightness of the connection, remains quickly removable and possibly reusable. To this end, the invention relates to a sealing device for flange flange-type piping connection systems, comprising a seal intended to be interposed between the two flanges of said connection system. According to a general characteristic of the invention, the seal comprises: at least one textile sealing strip intended to be interposed between the two flanges, and a rigid spacer also intended to be inserted between the two flanges, and a connecting element intended to maintain said sealing strip along the spacer, said device further comprising clamping means intended to hold the seal between the two flanges. In other words, the invention proposes to insert between the two flanges a seal instead of directly welding the bolts and the connecting flanges. Furthermore, the seal 10 comprises in addition to a sealing strip, a rigid spacer. This particular structure gives the seal a certain rigidity while ensuring the sealing of the connection system, unlike elastomer seals described for example in US 7 070 187.

According to one embodiment, the device may comprise two textile sealing strips arranged symmetrically on each side of the spacer. Preferably, said connecting member is a mesh which is wider in width than the spacer, and which is disposed between the lower flange and the spacer. The use of the mesh ensures a rigid and constant mechanical connection over time. According to one embodiment, said sealing strip is folded into two main folds so as to form a U turned towards the spacer, the outer edge of said screen being sewn between the two main folds of the sealing strip. The folding of the sealing strip makes it possible to avoid fraying the textile used. On the other hand, the stitching makes it possible to make the connection between the fabric strip and the mesh and to maintain the textile sealing strip in place. This type of connection is particularly suitable for textiles and mesh because of their mesh structure allowing the passage of the wire.

Preferably, said screen is sewn at least once to the sealing strip using a wire supporting high temperatures. The multiplication of the seams makes it possible to reinforce the solidity of the connection, whereas the use of a wire supporting high temperatures makes it possible to use the seal for connection systems on pipes in which hot gases circulate. Moreover, each main fold of the sealing strip can be folded at least once on itself. This embodiment where the number of folds is increased, makes it possible to increase the thickness of the fabric strip while avoiding fraying. Alternatively, a main fold of the sealing strip may be folded a first number of times, and the other major fold a second number of times, said first number being different from said second number. This technique has the advantage of moving the position of the mesh on the height of the seal, which is particularly interesting in case of thick textile. Preferably, the textile of the sealing strips may be of high temperature supporting fibers. In this way, the invention is particularly suitable for piping where hot gases circulate. For example, the textile of the sealing strips may be of woven fabric.

Said mesh may be in turn stainless steel of 0.2 mm thick fine mesh. The spacer can be in turn stainless steel. Furthermore, said spacer may comprise rounded corners so as not to mark the connecting element, particularly if it is made of mesh.

For example, the clamping means may comprise at least one bolt passing through the grids and the seal from one side to the other. The spacer has a hole for the passage of the bolt, said hole having an oblong shape so as to allow a greater possibility in mounting tolerances. In the case where the clamping means comprise at least one bolt, the device may further comprise a double brake pad disposed between each bolt and the outer face of each flange. These brake pads make it possible to improve the locking of all the elements of the device according to the invention. Other advantages and features of the invention will appear on examining the detailed description of an embodiment of the invention which is in no way limitative, and the attached drawings in which: FIG. 1 represents a sectional view of a first embodiment of a device according to the invention; Figure 2 shows in more detail the embodiment of Figure 1, Figure 3 shows in more detail an example of a seal used for the first embodiment according to the invention; FIG. 4 illustrates more precisely a sealing strip according to the invention; Figures 5a to 5d illustrate different methods of folding a sealing strip according to the invention. FIG. 6 represents a sectional view of a second embodiment of a device according to the invention; Figure 7 shows in more detail the embodiment of Figure 6; FIG. 8 represents an example of a seal according to the second embodiment according to the invention; Referring to FIG. 1, there is shown a flange-type connection system connecting two pipes referenced 1 and 2, the pipe 1 being aligned in the extension of the pipe 2. The connection system comprises a lower flange 3 and an upper flange 4. These flanges each comprise two parts 10 forming an L. The lower flange 3 is sealed on the pipe 1 by means of one of its branches 5, and the upper flange 4 is sealed on the pipe 2, also via one of its branches 5, symmetrically with respect to the lower flange 3. The projections 7 and 8 of the two flanges 3 and 4 are perpendicular to the pipes 1 and 2 These pipes 1 and 2, here arranged vertically, may be formed of a pipe 9 coated with a seal 10 sealing the pipe. The connection system further comprises a seal 20 1l, intended to be interposed between the projections 7 and 8 of the two flanges 3 and 4 This seal 11 is formed of three parts namely a spacer 12; a connecting element, constituted in the example represented by a grid 13 (here of rectangular shape); and a pair of sealing strips 14 and 15 to which the mesh 13 is attached.

The seal 11 is held between the two flanges 3 and 4 by means of clamping means, here two bolts, a bolt 16 is shown in section in Figure 1. This bolt 16 is formed of a screw 17 and a nut 18. Each bolt passes right through the projecting portion of the flange 4, the gasket 11 and then the protruding part of the flange 3, via a corresponding hole in each of the three aforementioned parts, as can be seen on Figure 2.

Each hole is formed along an axis parallel to the edge formed by the two parts making up the flanges 4 and 3. The spacer 12, here of rectangular shape, is disposed between the two sealing strips 14 and 15. The mesh 13 is interposed between the lower face of the spacer 12 and the upper face of the protruding portion of the flange 3. The strips 14 and 15 are located along the spacer parallel to the edge formed by the two parts forming the flanges 3 and 4. This spacer 12 is preferably made of stainless steel. However, any other material can also be used depending on the working temperature and the mechanical strength required at the connection. The thickness of the spacer 12 is chosen according to the thickness of the seal to be compressed and the compression percentage of the seal structure. The spacer 12 is drilled with holes here in number of two, so as to allow the passage of the screw 17. These through holes can be circular with a game for easy assembly. Alternatively, these holes may be oblong in shape to allow a greater possibility in mounting tolerances. Preferably, the right angles of the four corners of the spacer 12 are rounded so as not to mark the grid 13. The spacer 12 makes it possible to transmit the forces between the two flanges. In particular, it cooperates with the mesh 13 to ensure a rigid mechanical connection and constant over time, transmitting the clamping force applied by the bolt on one of the flanges to the other flanges, by the intermediate toasting. Moreover, when the two flanges 4 and 3 are tightened around the gasket 11, the spacer 12 will make it possible to hold the two sealing strips in place thanks to the mesh 13 compressed between the lower flange 3 and the lower face of the gasket. the spacer 12.

The sealing strips 14 and 15 and the mesh 13 will be described in more detail below. In this embodiment, a double brake pad is placed between the bolts and the flanges.

More specifically, a first plate 19 is disposed between the head of the screw 17 and the projecting portion 7 of the upper flange 4 and a second plate 20 is disposed between the projecting portion 8 of the lower flange 3 and the nut 18, in order to effect the blocking of the assembly comprising the seal 11 and the flanges 4 and 3 (Figure 1 10 represent the upper and lower plates 19 and 20 in section). Referring now to Figure 3, which illustrates in more detail the sealing strips 14 and 15 and the mesh 13. Preferably, the sealing strips 14 and 15 are manufactured in a fabric woven with a textile fiber supporting high temperatures. By way of example, mention may be made of Aramide type wires with a temperature of 380.degree. C., glass strands with a temperature of 500.degree. C., glass strands of type VR 750 supporting a temperature of 750.degree. C., glass strands. type HT 1000 supporting a temperature of 1000 C, VHTC type son 20 supporting temperatures of between 650 and 1050 C, NEFATEX type 1390 son supporting temperatures up to 1390 C, or NEFATEX son type 1200 supporting temperatures up to 1200 C. Of course, it is possible to use any other type of wire supporting high temperatures.

As shown in FIG. 4, the weaving used for the textile of the sealing strips (here the strip 14) may be square mesh of length a (or by rectangular extension of length a and width b) or mesh Diamond-shaped of dimension a. Of course, any type of section can be used for textile weaving.

2909742 8 The diameter of the yarn to be used for the textile is related to the choice of the mesh and the thickness of the textile that one seeks to obtain. Referring again to FIG. 3, the grid 13 is also pierced with two holes so as to allow the bolts to pass. These holes are in correspondence with those drilled in the spacer 12 and may have the same shape characteristics. The mesh 13 may be made of stainless steel with a thickness of 0.2 mm. However, any other material can be used, which is determined by the working temperatures, as well as their mechanical strength with respect to the clamping performed by the two flanges. The grid mesh is preferably fine. Thus, the sealing strips can be fixed to the mesh 13 by means of holding seams 21 and 22. The yarns used for these seams preferably support high temperatures. For example, they can be made using the same types of son used to weave the textile sealing strips 14 and 15, stated above.

More specifically, each textile strip 14 and 15 is folded into two main folds, so as to form a U directed towards the inside of the joint, the edges of the mesh 13 being placed between each fold (said main fold). Then each strip 14 is sewn by first passing through one of the upper main ply stitches and then through a mesh of the mesh, then through a mesh of the lower main ply of the sealing strip and thus right now. Any other sewing technique can be used such as the garter stitch. Thus, for sewing, different types of wire diameter can be used depending on the section of the mesh 13.

Only one seam per strip can be made, but several seams serve to reinforce the connection between each sealing strip and the screen.

2909742 9 Note that the mesh of the mesh 13 must allow the passage of the thread and the needle during sewing. Figures 5a to 5d show different methods of folding the sealing strips 14 and 15 with respect to the mesh.

The method used for FIG. 5a proposes to fold each main fold of the sealing strip (here the sealing strip referenced 14) once on itself, so as to avoid the fraying of the textile. The method used for FIG. 5b proposes folding each major fold several times on itself so as to increase the thickness of the textile strip while avoiding fraying. Figure 5c proposes to fold each main fold a greater number of times than in Figure 5b. The proposed method for Figure 5d also proposes to fold each main fold several times over itself, but one fold being folded a greater number of times than the other fold. This technique allows to move the roasting position on the height of the sealing strip. This method is particularly suitable for particularly thick textile cases.

Of course, other folding methods are possible. The mesh will therefore be positioned at the symmetry level of the sealing strip, that is to say between each fold main folded on itself or not, with the exception of the method illustrated in Figure 5d where the the position of the grid is voluntarily moved over the height.

Thus arranged, the sealing strips 14 and 15 seal the junction made by the connection system between the two pipes 1 and 2. FIGS. 6 and 7 illustrate another embodiment of the device according to the invention. where a single referenced sealing strip 30 is used. This is arranged along the spacer on the side of the pipes 1 and 2.

For this embodiment, the spacer 12 of the gasket 11 may be wider than that used for the embodiment shown in FIG. 1. FIG. 8 shows in more detail the gasket 11 comprising a mesh 13 and a gasket 13. sealing strip 15, held along the mesh 13 by a seam 22. Thanks to the invention, a sealing device is obtained for a rigid flange type connection system (thanks to the use of a spacer and a suitable connecting element, for example in wire mesh) and sealed thanks to the use of textile sealing strips. Furthermore, the device is particularly suitable for connecting conduits in which a hot gas circulates, by the use of textiles supporting high temperatures for the production of sealing strips. For example, the invention can be used for chimneys, pipes in the context of the fumistery, as well as for any type of chimney exhaust duct, hatch and oven door. The use of a gasket makes it easy and quick to disassemble the connection system, without destroying the bolts, which reduces the overall cost and time of maintenance performed on this system.

Claims (15)

  1-Sealing device for flange flange-type pipe connection system, comprising a seal (11) intended to be inserted between the two flanges (3, 4) of said connection system, characterized in that the seal comprises at least one textile sealing strip (15) intended to be interposed between the two flanges; a rigid spacer (12) also intended to be interposed between the two flanges (3, 4), and an element link (13) for holding said sealing strip (15) along the spacer (12), said device further comprising clamping means (16) for holding the seal (11) between the two flanges (4, 3).   2- Device according to claim 1, comprising two textile sealing strips disposed symmetrically on each side of the spacer (14, 15).   3- Device according to claim 2, wherein said connecting element (13) is a mesh which has a width greater than that of the spacer (12), and which is arranged between the lower flange (3) and the spacer (12).   4-Device according to claim 3, wherein said sealing strip (15) is folded into two main folds so as to form a U facing towards the spacer, the outer edge of said mesh (13) being sewn between the two plies of the sealing strip (15).   5. Device according to claim 4, wherein said screen (13) is sewn at least once to the sealing strip using a wire supporting high temperatures. 2909742 12   6-Device according to one of claims 4 or 5, wherein each main fold of the sealing strip (15) is folded at least once on itself.   7-Device according to one of claims 4 or 5, wherein 5 a main fold of the sealing strip is folded a first number of times, and the other main fold is folded a second number of times, said first number being different from said second number.   8- Device according to one of the preceding claims, wherein the textile sealing strips is fiber supporting high temperatures.   9- Device according to one of the preceding claims, wherein the textile sealing strips is woven fabric.   10- Device according to one of claims 2 to 9, wherein said mesh (13) is stainless steel of 0.2 mm thick fine mesh.   11- Device according to one of the preceding claims, wherein said spacer (12) is made of stainless steel.   12- Device according to one of the preceding claims, wherein said spacer (12) comprises rounded corners. 20   13- Device according to one of the preceding claims, wherein the clamping means (16) comprise at least the bolt through the flanges and the seal from one side.   14- Device according to claim 13, wherein the spacer has a hole for the passage of the bolt, said hole 25 having an oblong shape.   15- Device according to one of claims 13 or 14, further comprising a plate (19, 20) of double brake disposed between each bolt and the outer face of each flange (3, 4) .30