SEALING AND LOCKING ARRANGEMENT FOR A FLEXIBLE PIPE CONNECTION

Description

Technical field

[0001] The present invention relates to the field of producing a flexible and locked tubular joint between two pipe elements, one of which has a plain end and the other a socket end. In this field, it mainly relates to a ready-to-install locking assembly, which allows the axial locking of a flexible tubular joint provided with a sealing counterflange for compressing a joint gasket positioned between the plain end and the socket of the socket end. The invention finds its application more particularly for connecting pipes, in particular made of ductile cast iron, such as those used for example for the transport of drinking water, for sanitation or for irrigation. Prior art

[0002] A flexible mechanical tubular junction between two pipeline elements is described for example in French patent application FR 1 157 516 and usually comprises: a socket end at one end of one of the two pipe elements, a plain end at the end of the other pipe element, said plain end being capable of being inserted coaxially into the socket of said socket end, a joint gasket consisting of a sealing ring, made of elastic material, and in particular of elastomer or rubber, a sealing counterflange.

[0003] The sealing ring is adapted to be mounted coaxially between the inner face of the socket of said socket end and the outer face of the plain end inserted coaxially into the socket of said socket end. The sealing counterflange makes it possible to compress the sealing ring at least axially in the socket of the socket end, in order to ensure a seal between the plain end and the socket end.

[0004] An advantage of this type of tubular joint is a certain bending capacity, allowing a slight angular deviation, typically up to 5°, of the plain end relative to the socket end both during or after installation and / or a slight eccentricity, without loss of sealing.

[0005] On the other hand, a disadvantage of this type of tubular joint lies in the significant risks of accidental disengagement of the plain end from the socket end, in particular under the effects of the pressure of the fluid, and for example water, circulating through the tubular joint or during handling or installation in the ground of the tubular joint.

[0006] To reduce these risks of disengagement, one solution may be to perform a weld on site at the interface between the spigot end and the socket of the socket end. However, performing this weld is extremely restrictive and difficult, requires special equipment and welding consumables, and requires expertise.

[0007] To reduce these risks of disengagement, it is also known to improve the aforementioned flexible tubular junction by adding axial locking means, so as to obtain a locked flexible tubular junction.

[0008] A first type of locking solution consists of adding locking inserts in the seal gasket, these inserts being able to be integrated into the seal ring or be separated from the seal ring. This particular type of flexible tubular joint locked by means of one or more locking inserts is described for example in French patent application FR 2 984 985, in international patent application WO 03 / 027560 or in French patent application FR 3 029 260. In this locking solution, under the effect of the compression of the seal gasket exerted by the sealing counterflange and the pressure of the liquid flowing through the joint, the locking inserts engage in the wall of the spigot end, which simultaneously allows the tightening of the sealing counterflange to axially lock, to a certain extent, the spigot end relative to the socket end.

[0009] A disadvantage of these locking inserts, however, lies in the delicate adjustment of the compression of the sealing ring between the plain end and the socket end. Indeed, to obtain a seal by compression of the sealing ring and an effective axial locking of the plain end and the socket end, it is necessary to use a sufficient clamping force while correctly holding the seal in place in the socket, in order to allow the entry into service of the locking inserts when the junction is pressurized. But conversely, depending in particular on the hardness of the sealing ring, excessive compression of this sealing ring can lead to deterioration of the sealing ring (in particular the appearance of cracks, tears or ruptures in the sealing ring), which is detrimental to the seal.In this type of tubular joint, there is therefore a risk, when tightening, of compressing the sealing ring too strongly or of misaligning it inside the socket and of causing a detrimental sealing defect and leaks at the level of this sealing ring.

[0010] A second type of locking solution has also been proposed which makes it possible to avoid the aforementioned drawback of locking inserts and which has been described in particular in American patent US 5,544,922.

[0011] In this solution, axial locking is achieved by means of a sealing counterflange, which has been improved by incorporating locking elements distributed around the entire circumference of the sealing counterflange. Each locking element is adapted to be individually tightened against the spigot end in order to axially lock the tubular joint, once the sealing counterflange itself has been tightened to compress the sealing ring.

[0012] In this solution, the compression sealing function of the joint ring and the locking function are thus advantageously independent of each other. On the other hand, this solution for producing a locked flexible tubular junction has the major disadvantage of being long and tedious to implement. It is necessary to position each locking element in the counterflange, then individually tighten each locking element one after the other, checking for each locking element that the tightening is correct.

[0013] Another disadvantage of this solution is that it requires the implementation of a very specific sealing counterflange, and cannot be used to improve the axial locking of an existing flexible tubular junction while retaining the sealing counterflange of this junction.

[0014] Furthermore, in patent application US 2016 / 290538, a locking assembly has already been proposed which is intended to be fitted to a sealing counterflange for a tubular joint of the type comprising a plain end, a socket end, and at least one joint gasket. This locking assembly comprises two separate pressure plates, each in the shape of an arc of a circle, and a retaining accessory in the form of a flexible retaining collar, which can be tightened by means of tightening bolts. Each pressure plate has through holes used for its mounting on the sealing counterflange and on the socket end by means of fixing bolts. Each pressure plate has recessed portions in the shape of an arc of a circle, which make it possible to accommodate flange portions, which are projecting at the periphery of the external face of the retaining collar.

[0015] The use of these two pressure plates does not allow for a robust assembly and also complicates assembly operations.

[0016] US Patent 4,867,488 discloses a sealing and locking assembly. Objectives of the invention

[0017] The invention relates to a ready-to-assemble locking assembly, which is adapted to be easily and robustly mounted on a sealing counterflange of a flexible tubular junction of the type comprising a plain end, a socket end, and at least one joint gasket.

[0018] In addition to the ease and robustness of assembly, the invention also makes it possible to overcome the aforementioned drawback of the delicate adjustment of the compression of the joint packing in the aforementioned tubular junctions of the prior art with locking inserts, while being simple and quick to implement, unlike in particular the solution of the aforementioned American patent US 5,544,922.

[0019] Preferably, this new technical solution also makes it possible to obtain reliable axial locking which preferably avoids the need for additional welding on site.

[0020] Preferably, the technical solution of the invention can also, if necessary, be easily used to improve the axial locking of an existing flexible tubular junction, while retaining the sealing counterflange of this junction. Summary of the invention

[0021] The first subject of the invention is a sealing and locking assembly according to claim 1.

[0022] More particularly, but optionally according to the invention, the sealing and locking assembly of the invention may comprise the technical characteristics defined in claims 2 to 10.

[0023] The second subject of the invention is an assembly for producing a flexible and locked tubular junction, said assembly comprising a first pipe element comprising a socket end at at least one end, a second pipe element comprising a plain end at at least one end, at least one joint gasket adapted to be mounted between the socket of the socket end and the plain end inserted coaxially into said socket of the socket end, and said assembly comprising an above-mentioned sealing and locking assembly.

[0024] More particularly, but optionally according to the invention, the sealing and locking assembly of the invention may comprise the technical characteristics defined in claims 12 to 14.

[0025] The third object of the invention is a use of the above-mentioned assembly for producing a flexible and locked tubular junction.

[0026] The fourth subject of the invention is a method for producing a flexible and locked tubular junction using the above-mentioned assembly, and comprising the following successive steps: the retaining accessory is inserted inside the locking counterflange; the locking counterflange / retaining accessory assembly is mounted on the spigot end by sliding it axially over the spigot end; the sealing counterflange is mounted on the spigot end by sliding it axially over the spigot end; the spigot end is inserted coaxially into the socket of the socket end, the gasket having been previously positioned in the socket of the socket end; the locking counterflange is assembled with the sealing counterflange and with the socket end, preferably with axial clamping of the locking counterflange with the sealing counterflange and with the socket end, so as to compress the gasket by means of the sealing counterflange, preferably over the entire circumference of the spigot end;the retaining accessory is tightened onto the spigot end, with a clamping force sufficient to immobilize the retaining accessory on the spigot end. ; Brief description of the figures

[0027] The characteristics and advantages of the invention will appear more clearly on reading the detailed description below of a preferred embodiment variant of a flexible and locked tubular junction in accordance with the invention, which preferred embodiment variant is described by way of non-limiting and non-exhaustive example of the invention, and with reference to the appended drawings in which: there figure 1 is an exploded isometric view of an assembly in accordance with the invention and allowing the creation of a flexible and locked tubular junction between two pipeline elements; the figure 2 is a longitudinal sectional view of a flexible and locked tubular joint made by means of the assembly of the figure 1 ; there figure 3 is an isometric view of a spigot end over which is threaded a retaining collar, which is in two parts and which can be tightened so as to be immobilized on the spigot end; figure 4 is a longitudinal sectional view of the plain end and the retaining collar of the figure 3 . There Figure 5 is an isometric view of a preferred embodiment of the locking counterflange. Detailed description

[0028] It has been represented on the figure 1 a preferred embodiment of an assembly allowing the production of a flexible and locked tubular junction between two pipe elements 1 and 2. The pipe element 1 comprises, at at least one of its ends, a socket end 10 comprising a clamping flange 101; the pipe element 2 comprises, at at least one of its ends, a plain end 20 which is capable of being inserted coaxially into the socket 100 of the socket end 10.

[0029] More particularly, the clamping flange 101 may be formed by a cylindrical collar which extends continuously over the entire circumference of the socket end 10. In another variant, illustrated for example in the figure 1 of French patent application FR 2 984 985, the clamping flange 101 may consist of several projecting elements with a flange function, which are distributed over the external circumference of the socket end 10.

[0030] The pipe element 1 or 2 can generally be a straight or bent and / or cross-sectional pipe or pipe fitting.

[0031] There figure 2 represents a locked flexible tubular junction, with longitudinal central axis X, made by means of the entire figure 1and in which, in a non-limiting and non-exhaustive manner of the invention, the pipe element 1 is for example constituted by a connector, in particular a connector forming a 90° elbow and the pipe element 2 is a pipe.

[0032] The material constituting the pipeline elements 1 and 2 is of no importance for the invention. However, the pipeline elements 1, 2 are preferably made of ductile cast iron, in particular when they are intended to be buried in the ground and / or to be used for the transport of drinking water, for sanitation or for irrigation.

[0033] In reference to the figure 1 , in addition to the two pipe elements 1 and 2, the assembly of the invention comprises a joint gasket 3, a cylindrical sealing counterflange 4 allowing the compression of the joint gasket 3 and a ready-to-assemble locking assembly 5.

[0034] In the particular example illustrated on the figures 1 And 2 , the seal 3 is constituted by a seal ring 30, made of elastic material, and in particular of elastomer or rubber. In a manner known per se, this seal ring 30 is adapted to be positioned coaxially in the socket 100 of the socket end 10, so as to provide a seal between the internal face of this socket 100 and the external face of the plain end 20 inserted coaxially in the socket 100, over the entire circumference of the plain end 20.

[0035] In other embodiments covered by the invention, and in a non-exhaustive manner, the seal 3 may comprise several seal rings and / or may comprise locking inserts integrated into the seal ring 30 or separate from the seal ring 30, as described for example in French patent application FR 2 984 985. These locking inserts are for example made of metal, and in particular stainless steel.

[0036] The seal gasket 3 may also be of the same type as that described in French patent application FR 3 029 260 and comprise a compressible front seal ring adapted to be compressed by the sealing counterflange 4 and extended by a rear seal ring which is not compressed by the sealing counterflange 4. Furthermore, the seal gasket may be made of a single elastic material, and is for example made of EPDM or rubber or may be composed of several elastic materials which may be different, and in particular have different Shore hardnesses.

[0037] In reference to the figures 1 And 2, the cylindrical sealing counterflange 4 is adapted to be mounted by being threaded onto the plain end 20 and to be rigidly assembled with the socket end 10, by being axially clamped against the clamping flange 101 of the socket end 10, so as to compress, preferably at least axially, the seal ring 30 positioned between the plain end 20 and the socket 100 of the socket end 10.

[0038] More particularly, this sealing counterflange 4 comprises a cylindrical end whose annular front face 40 ( figure 2 ) is positioned opposite the seal packing 3, and more particularly the seal ring 30 when the counterflange 4 is mounted on the plain end 20, and which is brought into contact and compresses the seal packing 3, and more particularly the seal ring 30, preferably over its entire circumference, when the counterflange 4 is brought axially closer to the clamping flange 101.

[0039] The sealing counterflange 4 also comprises axial and through assembly openings 41, for example three in number, which are regularly distributed around its circumference, and which allow the mounting of clamping bolts through the sealing counterflange 4.

[0040] In the particular variant illustrated, the sealing counterflange 4 is made of a single piece. In other variants, it may be constituted by a rigid monolithic assembly of several pieces.

[0041] The ready-to-install 5-piece locking set includes: a cylindrical locking counterflange 50, which is separate from the sealing counterflange 4, and which is adapted to be mounted by being threaded onto the spigot 20 and to delimit an annular retaining chamber 51 ( figure 2) with the external face of the plain end 20, and assembly means 52, 53, which generally make it possible to rigidly assemble the locking counterflange 50 with the sealing counterflange 4 and the socket end 10, preferably in a removable manner and / or preferably with adjustable axial tightening of the locking counterflange 50 / sealing counterflange 4 / socket end 10 assembly.

[0042] More particularly, the locking counterflange 50 comprises axial and through assembly openings 501, for example three in number, which are regularly distributed around its circumference, and which allow the mounting of clamping bolts through the locking counterflange 50.

[0043] When the sealing counterflange 4 is mounted on the plain end 20, it is oriented relative to the locking counterflange 50, such that each assembly opening 41 of the sealing counterflange 4 is axially aligned (axis X of the figure 2 ) with an assembly opening 501 of the locking flange 50.

[0044] The assembly means 52, 53 comprise, for each pair of aligned assembly openings 41, 501, a clamping bolt consisting of a screw 52 with a threaded rod 520 associated with a nut 53. The threaded rod 520 of the screw 52 can be passed through the two assembly openings 41, 501 in opposite directions from each other, and the head 521 of the screw 52 can be axially locked against the clamping flange 101 of the socket end in the axial direction D of disengagement of the spigot end 20 ( figure 2 ).

[0045] Preferably as shown in the figures 1 And 2, the head 521 of each screw 52 forms a hook suitable for hooking onto the socket end 10, without it being necessary to pass the screw 52 through the wall of the socket end 10, which advantageously makes it possible to avoid drilling the wall of the socket end 10.

[0046] The clamping bolts 52, 53 advantageously make it possible, in a single operation, to rigidly assemble together the locking counterflange 50, the sealing counterflange 4 and the socket end 10, with adjustment of the axial tightening of the locking counterflange 50 / sealing counterflange 4 / socket end 10 assembly.

[0047] In another alternative embodiment, the assembly means 52, 53 may comprise first assembly means, for example of the clamping bolt type, adapted to fix the locking counterflange 50 to the sealing counterflange 4 and second assembly means, for example of the clamping bolt type, distinct from said first assembly means and adapted to fix the sealing counterflange with the socket end 10, preferably with a possibility of adjusting the axial tightening of the sealing counterflange 4 with the socket end 10.

[0048] The 5-piece ready-to-install locking set also includes: at least one retaining accessory 54, which is adapted to be inserted into the locking counterflange 50 while being positioned at least partly in said annular retaining chamber 51, and clamping means 55, which make it possible to immobilize said retaining accessory 54 on the plain end 20, by clamping the retaining accessory 54 on the plain end 20.

[0049] Generally speaking, with reference to the figure 2 , the locking counterflange 50 is adapted to axially block, at least in the axial direction of disengagement D of the plain end 20, said retaining accessory 54 positioned at least partly in said annular retaining chamber 51 and immobilized by clamping on the plain end 20.

[0050] In the particular variant illustrated, the locking counterflange 50 is made of a single piece. In other variants, it may be constituted by a rigid monolithic assembly of several pieces.

[0051] More particularly in the variant of the figure 2 , the portion of the internal face of the locking counterflange 50, which delimits said annular retaining chamber 51 with the external face of the plain end 20, comprises an annular retaining groove 502 having, in a longitudinal plane (plane of the figure 2 ), a concave curved profile allowing the aforementioned axial locking of the retaining accessory 54 in the axial direction of disengagement D.

[0052] Preferably as shown in the figure 2 , this concave curved profile of the annular groove 502 substantially forms an arc of a circle.

[0053] Preferably ( Figure 5 ) the internal face of the locking counterflange 50 comprises two annular retaining grooves 502 which are diametrically opposed and preferably symmetrical to each other with respect to the central axis of the locking counterflange 50.

[0054] Preferably ( Figure 5) the internal face of the locking counterflange 50 also comprises two notches 503 which are diametrically opposite and preferably symmetrical to each other with respect to the central axis of the locking counterflange 50. These two notches 503 are provided in this preferred embodiment variant to allow the passage of the lever arms 541b (described below) of the retaining accessory 54.

[0055] In the more general context of the invention, depending on the structure of the retaining accessory 54, the internal face of the locking counterflange 50 may also, in another variant, comprise a single annular retaining groove 502 which extends, for example, over 360°, i.e. over the entire circumference of the locking counterflange 50, or comprise more than two annular retaining grooves 502. The internal face of the locking counterflange 50 may also, in another variant, not comprise a notch 503, or comprise a different number of notches 503, and in particular a single notch 503.

[0056] Preferably, the locking counterflange 50 and the retaining accessory 54 are adapted relative to each other such that the retaining accessory 54 is adapted to be inserted coaxially inside said locking counterflange 50, in axial abutment against the internal face of the locking counterflange 50, so as to form a locking counterflange 50 / retaining accessory 54 assembly which is adapted to be mounted on the spigot 20 by being threaded onto the spigot 20.

[0057] Preferably, the locking counterflange 50 and the retaining accessory 54 are adapted relative to each other such that the retaining accessory 54 is capable of being inserted coaxially inside said locking counterflange 50 by simple axial fitting into the locking counterflange 50.

[0058] The retaining accessory 54 comprises ( figures 3 And 4) more particularly a retaining collar 540 capable of being tightened.

[0059] This retaining collar 540 is capable of being inserted coaxially into the locking counterflange 50.

[0060] Once the retaining collar 540 is inserted coaxially into the locking counterflange 50, the circumferential portion of the retaining collar 540 which is coaxial with an annular groove 502 is inserted into said annular groove ( figure 2 ).

[0061] The retaining collar 540 is capable of being tightened once it has been coaxially inserted into the locking counterflange 50.

[0062] Preferably, the retaining collar 540 of the retaining accessory 54 is adapted to be housed entirely between the inner face of the locking counterflange 50 and the outer face of the spigot 20 ( figure 2 ).

[0063] In the preferred embodiment of the attached figures, the retaining accessory 54 has a structure similar to that described for another application in European patent application EP 3 460 305.

[0064] More particularly, the retaining collar 540 comprises two rigid and preferably identical half-collars 541, which are assembled and whose spacing is adjustable so as to be able to tighten the retaining collar 540.

[0065] More particularly, each half-collar 541 comprises a semi-circular jaw 541a and is extended, at each end and in the axial direction, by a lever arm 541b. Each lever arm 541b comprises a through assembly hole 542 ( figure 4) for the passage of the screw 551 of a clamping bolt. The two half-collars 541 are assembled by means of the clamping bolts 551, 552, the screws 551 of the clamping bolts being passed through the clamping arms 541b and the tightening of the nuts 552 of the clamping bolts on the screws 551 making it possible to adjust the spacing of the two half-collars 541.

[0066] On its internal face intended to be oriented towards the plain end 20, each semi-circular jaw 541a has a toothed profile 541c allowing the semi-circular jaw 541a to bite into the wall of the plain end 20, during radial tightening of the collar by means of the tightening bolts 551, 552. This toothed profile 541c can be obtained by fixing a semi-circular toothing 541d attached to the inside of each semi-circular jaw 541a. This semi-circular toothing 541d can be made of metal, and preferably of stainless steel.

[0067] When the retaining collar 540 is threaded onto the spigot 20, tightening the bolts 551, 552 brings the two half-collars 541 closer together, so that the two semi-circular jaws 541a are radially tightened and bite into the wall of the spigot 20, sufficiently to reliably immobilize the retaining collar 540 relative to the spigot 20.

[0068] Preferably, the outer face 540a ( Figures 2 And 4 ) of the clamping collar 540 has a profile adapted to the concave curved profile of the annular groove 502 formed in the internal face of the locking counterflange 50, so as to contribute to the flexibility of the tubular junction by allowing an angular deviation between the central axis of the retaining collar 540 and the central axis of the locking counterflange 50, for example an angular deviation which can reach 5°.

[0069] Preferably, but not necessarily, each lever arm 541b also comprises, at its free end, a rectangular slot 543 ( figure 3 ), oriented parallel to the axis of the through-hole assembly 542, and the retaining collar comprises two pins 544, each pin 544 being adapted to be mounted in the slots 543 opposite two lever arms 541b.

[0070] The outer diameter of each pin 544, in the central portion of the pin 544 intended to be positioned between two lever arms 541b, is greater than the diameter of the two ends of the pin 544, which are intended to be inserted into the slots 543 of the lever arms 541b.

[0071] When tightening the collar on the plain end 20, each pin 544 makes it possible to maintain the alignment of the two half-collars 541 relative to the central axis of the plain end 20 and also makes it possible, thanks to its larger diameter central part, to act as a lever fulcrum advantageously allowing transmission of the tightening torque of the tightening bolts 551.

[0072] In another alternative embodiment, the retaining collar 540 may not include the slots 543 and pins 544. Construction of the locked flexible tubular junction in Figure 2

[0073] To make the locked flexible tubular junction of the figure 2 , we implement the following successive steps.

[0074] The retaining collar 540 of the retaining accessory 54 is mounted coaxially inside the locking counterflange 50, such that the two jaws 541a are positioned in the annular grooves 502 of the locking counterflange 50, the clamping bolts 551, 552 being loosened.

[0075] In this variant, this assembly can be carried out quickly and easily by substantially aligning the central axis of the retaining collar 540 with the central axis of the locking counterflange 50 and axially aligning the lever arms 541b of the retaining accessory 54 with the notches 503, then axially fitting the retaining accessory 54 into the locking counterflange 50 so that the retaining collar 54 is positioned in the annular grooves 502, the lever arms 541b being passed through the notches 503.

[0076] Then, the locking counterflange 50 / retaining accessory 54 assembly is mounted on the plain end 20 by threading it and sliding it axially on the plain end 20.

[0077] The sealing counterflange 4 is mounted on the spigot end 20 by threading it and sliding it axially onto the spigot end 20, and by orienting it relative to the locking counterflange 50, such that each assembly opening 41 of the sealing counterflange 4 is axially aligned with an assembly opening 501 of the locking counterflange 50.

[0078] The plain end 20 is inserted coaxially into the socket of the socket end 10, the joint gasket 3 having been previously correctly positioned in the socket 100 of the socket end 10. The insertion depth of the plain end 20 is marked and checked in the usual manner by means of an insertion mark made on the external face of the plain end 20.

[0079] In the context of the invention, the plain end 20 may advantageously not be chamfered.

[0080] The sealing counterflange 4 and the locking counterflange 50 are brought together with the retaining accessory 54 in the direction of the socket 100 of the socket end 10, such that the sealing counterflange 4 is in contact with the seal ring 30 of the seal gasket 3.

[0081] The threaded rods 520 of the screws 52 of the clamping bolts are passed through the assembly openings 41, 501 of the two counterflanges 4 and 50, the head 521 of the screws 52 being in abutment against the clamping flange 101 of the socket end 10, then the nuts 53 of the bolts are positioned and tightened on the screws 52, using for example a torque wrench, so as to apply an appropriate and controlled tightening torque. This axial tightening makes it possible to assemble the sealing counterflange 4 / locking counterflange 50 / retaining accessory 54 assembly with the socket end 10 by tightening the sealing counterflange 4 against the seal ring 30 of the seal gasket 3, so that the seal ring 30 is compressed by the sealing counterflange 4 for an improved seal.

[0082] Once all bolts 52, 53 have been tightened, tightening bolts 551, 552 are tightened so as to radially tighten retaining collar 540 on the spigot end, with sufficient tightening torque so that retaining collar 540 bites appropriately and sufficiently into the wall of spigot end 20, in order to reliably immobilize retaining collar 540 on spigot end 20.

[0083] In reference to the figure 2 , once the retaining accessory 54 is inserted into the locking counterflange 50 and immobilized by clamping on the plain end 20 and once the locking counterflange 50 is assembled with the sealing counterflange 4 and with the socket end 10, the retaining collar 540 of the retaining accessory 54 is axially blocked in the axial direction of disengagement D of the plain end and is preferably radially blocked between the locking counterflange 50 and the plain end 20.

[0084] The locking counterflange 50 is not in contact with the plain end 20, and there remains between the locking counterflange 50 and the plain end 20 a minimum operating clearance (E) over the entire periphery of the plain end 20 allowing an angular deviation between the central axis of the plain end (20) and the central axis of the locking counterflange (50), and preferably an angular deviation which can reach 5°.

[0085] At the end of this succession of steps, we obtain the flexible and locked tubular junction of the figure 2 in which: an angular deviation of the spigot end 20 relative to the socket end 10 is permitted, for example and in a non-limiting manner a maximum deviation of the order of 5°; compression of the seal ring 30 by the sealing counterflange 4 is obtained for improved sealing between the socket end 10 and the spigot end 20 over the entire circumference of the spigot end 20. axial locking of the spigot end 20 in the socket end is obtained by means of the retaining accessory 54 (retaining collar 540), which is immobilized on the spigot end 20 and which is axially blocked in the disengagement direction D by the locking counterflange 50, which allows the flexible and locked tubular joint to withstand a significant pressure of a fluid, and in particular water, circulating through the joint (for example and in a non-limiting manner a pressure of up to 25 Bars).

[0086] Advantageously, the axial locking by the locking counterflange 50 and the compression of the seal packing 3 by the sealing counterflange 4 are independent, which facilitates and allows optimal adjustment of the compression of the seal packing 3 for optimal sealing and optimal adjustment of the axial locking of the spigot end 20 relative to the socket end 10, without prejudice to the compression of the seal packing 3.

[0087] Furthermore, the implementation of the locking counterflange 50 does not compromise the flexibility of the tubular junction.

[0088] Preferably, the sealing counterflange 4, the locking counterflange 50, and the retaining accessory 54 (with the possible exception of the semi-circular teeth 541d) are made of ductile cast iron.

[0089] Advantageously, the ready-to-assemble locking assembly 5 of the invention can further advantageously be used to improve the axial locking of an existing flexible tubular junction using a sealing counterflange associated with shorter clamping bolts. In this case these shorter clamping bolts are replaced by the clamping bolts 52, 53 of the locking assembly 5 which are longer to take into account the addition of the locking counterflange 50.

[0090] Thus, the ready-to-assemble locking assembly 5 can advantageously be marketed with the sealing counterflange 4 or separately without the sealing counterflange 4.

Claims

1. Sealing and locking assembly (4; 5) for a flexible tubular joint of the type comprising a spigot end (20), a socket end (10), and at least one gasket (3), said sealing and locking assembly (4; 5) comprising a ready-to-mount locking assembly (5) and a sealing mating flange (4), wherein said ready-to-mount locking assembly (5) comprises: - a cylindrical locking mating flange (50), which is suitable for mounting on the spigot end (20) by being threaded onto the spigot end (20) and for delimiting an annular retaining chamber (51) with the outer face of the spigot end (20), - means (52; 53) for assembling the locking mating flange (50) with the sealing mating flange (4) and with the socket end (10), - at least one retaining accessory (54), which is suitable for being positioned at least partially in said annular retaining chamber (51), and - clamping means (55), which make it possible to secure said retaining accessory to the spigot end by clamping the retaining accessory (54) onto the spigot end (20), wherein the locking mating flange (50) is suitable for axially locking, at least in the axial direction of disengagement (D) of the spigot end, said retaining accessory (54) which is positioned at least partially in said annular retaining chamber (51) and secured to the spigot end (20), and wherein the sealing mating flange (4) is suitable for mounting on the spigot end (20) and for being joined to the socket end (10) and to the locking mating flange (50) of the ready-to-mount locking assembly (5), so as to compress, by means of the sealing mating flange, the gasket (3) which is mounted between the socket (100) of the socket end (10) and the spigot end (20) which is inserted coaxially into said socket (100) of the socket end (10).

2. Sealing and locking assembly (4; 5) according to claim 1, wherein said assembly means (52; 53) of the ready-to-mount locking assembly are suitable for axially clamping, preferably with an adjustable clamping force, the locking mating flange (50) to the sealing mating flange (4) and to the socket end (10).

3. Sealing and locking assembly (4; 5) according to any one of the preceding claims, wherein the portion of the inner face of the locking mating flange (50), which delimits said annular retaining chamber (51) with the outer face of the spigot end (20), comprises an annular retaining groove (502), and preferably wherein said annular groove (502) has a concave curved profile allowing axial locking of the retaining accessory (54) in the axial direction of disengagement (D), and more preferably has a circular arc profile.

4. Sealing and locking assembly (4; 5) according to claim 3, wherein the external face (540a) of the retaining accessory (54) which is intended to be in contact with this annular groove (502) has a profile allowing an angular deflection between the retaining accessory (54) and the locking mating flange (50) and preferably an angular deflection of up to at least 5°.

5. Sealing and locking assembly (4; 5) according to any one of the preceding claims, wherein the retaining accessory (54) comprises a retaining collar (540) capable of being inserted coaxially into the locking mating flange (50) and is capable of being tightened once it has been inserted coaxially into the locking mating flange (50), and more preferably wherein the retaining collar (540) of the retaining accessory (54) is suitable for being housed entirely between the inner face of the locking mating flange (50) and the outer face of the spigot end (20).

6. Sealing and locking assembly (4; 5) according to claim 5, wherein the retaining collar (540) comprises two half-collars (541) which are joined together, the spacing of which is adjustable.

7. Sealing and locking assembly (4; 5) according to any one of the preceding claims, wherein the retaining accessory (54) comprises, on its inner face which is intended to be oriented toward the spigot end (20), a toothed profile (541c) allowing the retaining accessory (54) to bite into the wall of the spigot end (20), when the retaining accessory (54) is tightened.

8. Sealing and locking assembly (4; 5) according to any one of the preceding claims, wherein the locking mating flange (50) and the retaining accessory (54) match one another such that the retaining accessory (54) is capable of being inserted coaxially inside said locking mating flange (50), axially abutting the inner face of the locking mating flange (50), so as to form a locking mating flange (50) / retaining accessory (54) assembly which is capable of being mounted on the spigot end (20) by being threaded onto the spigot end (20), and preferably wherein the locking mating flange (50) and the retaining accessory (54) match one another such that the retaining accessory (54) is capable of being inserted coaxially inside the locking mating flange (50) by simple axial socketing in the locking mating flange (50).

9. Sealing and locking assembly (4; 5) according to any one of the preceding claims, wherein the locking mating flange (50) is made of a single part or of a rigid monolithic assembly of several parts.

10. Sealing and locking assembly (4; 5) according to any one of the preceding claims, wherein the sealing mating flange (4) has one or more axial assembly through-openings (41) distributed around the circumference of the locking mating flange (5), wherein the locking mating flange (50) comprises one or more axial assembly through-openings (501) distributed around the circumference of the locking mating flange (5), and wherein the locking mating flange (50) and the sealing mating flange (4) are suitable for being positioned against each other in axial alignment such that each assembly opening (501) of the locking mating flange (50) is axially aligned with an assembly opening (41) of the sealing mating flange (4).

11. Assembly for producing a flexible and locked tubular joint, said assembly comprising a first pipe element (1) comprising a socket end (10) at at least one end, a second pipe element (2) comprising a spigot end (20) at at least one end, at least one gasket (3) which is suitable for being mounted between the socket (100) of the socket end (10) and the spigot end (20) which is inserted coaxially into said socket (100) of the socket end (10), and said assembly comprising a sealing and locking assembly (4; 5) according to any one of the preceding claims.

12. Assembly according to claim 11, wherein the locking mating flange (50) and the retaining accessory (54) are suitable for allowing angular deflection between the central axis of the spigot end (20) and the central axis of the locking mating flange (50), when the retaining accessory (54) is inserted into the locking mating flange (50) and is clamped to the spigot end (20) and when the locking mating flange (50) is joined to the sealing mating flange (4) and to the socket end (10), and preferably an angular deflection of up to 5°.

13. Assembly according to claim 11 or 12, wherein the locking mating flange (50) and the retaining accessory (54) match one another in such a way that, once the retaining accessory (54) is inserted into the locking mating flange (50) and clamped to the spigot end (20), and once the locking mating flange (50) is joined to the sealing mating flange (4) and to the socket end (10), the retaining accessory (54) is locked axially in the axial direction of disengagement (D) of the spigot end and is preferably locked radially between the locking mating flange (50) and the spigot end (20), and the locking mating flange (50) is not in contact with the spigot end (20), and preferably wherein the locking mating flange (50) is designed such that once the retaining accessory (54) has been inserted into the locking mating flange (50) and clamped to the spigot end (20), and once the locking mating flange (50) is joined to the sealing mating flange (4) and to the socket end (10), a minimum operating clearance (E) remains between the locking mating flange (50) and the spigot end (20) over the entire periphery of the spigot end (20), allowing an angular deflection between the central axis of the spigot end (20) and the central axis of the locking mating flange (50), and preferably an angular deflection of up to 5°.

14. Assembly according to any one of claims 11 to 13, wherein the first pipe element (1) is a pipe fitting or a pipe, preferably made of ductile cast iron, and the second pipe element (2) is a pipe fitting or a pipe, preferably made of ductile cast iron.

15. Use of the assembly of any one of claims 11 to 14 to produce a flexible and locked tubular joint.

16. Method for producing a flexible and locked tubular joint by means of the assembly of any one of claims 11 to 14, comprising the following successive steps: - inserting the retaining accessory (54) into the locking mating flange (50); - mounting the locking mating flange (50) / retaining accessory (54) assembly on the spigot end (20) by sliding it axially onto the spigot end (20); - mounting the sealing mating flange (4) on the spigot end (20) by sliding it axially onto the spigot end (20); - inserting the spigot end (20) coaxially into the socket (100) of the socket end (10), the gasket (3) having been previously positioned in the socket (100) of the socket end (10); - joining the locking mating flange (50) to the sealing mating flange (4) and to the socket end (10), preferably by axial clamping of the locking mating flange (50) to the sealing mating flange (4) and to the socket end (10), so as to compress the gasket (3) by means of the sealing mating flange (4), preferably over the entire circumference of the spigot end (20); - tightening the retaining accessory (54) onto the spigot end (20) with a clamping force sufficient to secure the retaining accessory (54) to the spigot end (20).