Title of Invention

"A DEVICE FOR THE JOINT BETWEEN A SMOOTH END AND A FLANGE OF TWO PIPELINE ELEMENTS"

Abstract

This invention relates to a device (7) for the joint between a smooth end (1) and a flange (3) of two pipeline elements (2,4), comprising an axial-compression packing (8) made of elastomer. This packing comprises a body (15) for bearing against a counterflange (11) for compression of the packing (8) and, at the front of this body (15) and integral with the latter, a heel (16) for bearing against the flange. A radially outer siurface (22) of the body is intended to bear on a reaction surface (27, 27A) of the counter-flange (11); a radially inner surface (18) of the body (15) is intended to bear on the radially outer surface (20) of the smooth end (1); and a front extremity surface (31) of the heel (16) is intended to bear on the flange (:.)• in order to, ensure the leaktightness of the joint between the two pipeline elements (2,4). The body (15) has at least one recess (26) for the expansion of the elastomer of the compressed packing, and the device (7) is provided with a means for limiting the expansion of the heel (16) radially outwards. Application to the joint between pipeline pipes. Fig. 1

Full Text

The present invention relates to a device for the joint between a smooth end and a flange of two pipeline elements, comprising an annular axial-compression packing made of elastomer, this packing comprising a body for bearing against a counterflange for compression of the packing and, at the front of this body and integral with the latter, a heel for bearing against the flange, a radially outer surface of the body being intended to bear on a reaction surface of the counterflange, a radially inner surface of the body being intended to bear on the radially outer surface of the smooth end, and. a front extremity surface of the heel being intended to bear on the flange in order to ensure the leaktightness of the joint between the two pipeline elements. The words "front" and "rear" are used in relation to the direction of displacement of the counterflange when the packing is subjected to compression. such a device is used for the st irjoint between pipes, in particular pipes made of ductile caon,, or for the joint between a pipe and a valve apparatus such a gate valve. For such a joint, generally the counterflange and then the device is slipped onto the front extremity of the smooth and of a first pipe, and this smooth end is brought close to the flange of a second pipe or of a valve apparatus. The counterflange is generally connected to the flange by bolts which, by tightening, enable the counterflange to be brought closer to the flange and thus ensure that the packing is subjected to compression. The body of the packing is then lodged in an annular compression chamber delimited by the reaction surface of the counterf lange and the radially outer surface of the smooth end. The packing must be able to perform its function equally well in the case where the radial play between the counterflange and the smooth end and/or the axial play between the smooth end and the flange are substantial, and in the case where one or both of these plays are minimal, so as to be able to adapt to the different configurations which are generally encountered, However, these requirements are not really compatible. This is because, in the first case, the space available for the expansion of the elastomer of the compressed packing is relatively large. Consequently, the latter must have sufficient dimensions to be able to perform its function. Now, in the second case, the space available for the expansion of the elastomer of this sane compressed packing is much smaller. Very often it is then found, especially when the radial play is minimal, that the packing is incorrectly positioned when it is subjected to compression, in particular in terms of the positioning between the heel and the flange, which leads to sealing clefects. For a locked joint between two pipeline elements, inserts are generally provided in a rear extremity portion of the body, each insert having a radially inner surface, of which a catching relief is intended to bear on the radially outer surface of the smooth end of the first pipe in order to lock the joint between the two pipeline elements. When the play is minimal, in particular when the radial play is minimal, problems in terms of the positioning of the packing of such a device are also observed, with, for- example, the appearance of expansion bulges of the elastomeir outside the counterflange, to the rear of the latter, and/or with undulation phenomena of the elastomer around the inserts, which may lead to sealing defects of the joint between the two pipeline elements. The object of the present invention is to solve the above-mentioned problems and, in particular, to provide a packing device which is easy to mount and demount, takes up little space, is inexpensive and ensures good leaktightness of a joint between pipeline elements over a wide range of plays between the parts of the joint, in particular when the radial play between the counterflange and the smooth end of the joint is minimal, and up to relatively high pressures, for example 16 bars. To that and, the subject of the invention is a device for the joint between a smooth end and a flange of two pipeline elements, comprising an axial-compression packing made of elastomer, this packing comprising a body for bearing against a counterflange for compression of the packing and, at the front of this body and integral with the latter, a heel for bearing against the flange, a radially outer surface of the body being intended to bear oh a reaction surface of the counterflange, a radially inner surface of the body being intended to bear on the radially outer surface of the smooth end, and a front extremity surface of the heel being intended to bear on the flange in order to ensure the leaktightness of the joint between the two pipeline elements, characterized in that the body has at least one recess for the expansion of the elastomer of the compressed packing, and in that the device is provided with a means for limiting the expansion of the heel radially outwards. According to particular embodiments, the device may comprise one or more of the following features: - the recess is an annular recess formed on the radially inner surface or on the radially outer surface of the body; - the recess is formed on the radially inner surface of the body, this recess defining a cavity closed at least partially by a part of the packing forming an annular lip, eind the device comprises a member for holding the lip on the'radially outer surface of the smooth end, this member being lodged in the said cavity; - the said holding member is a split toric ring; - the recess is formed on the radially inner surface of the body, at least one other annular recess is formed on the radially outer surface of the body, and in that these two recesses are axially offset with respect to one another; - the means for limiting the expansion of the heel is a rigid, in particular metallic, ring, arranged in a radially outer part of the heel; - the means for limiting the expansion of the heel is an annular spring arranged in a radially outer part of the heel; - the said front extremity surface of the heel has at least one inclined part which diverges rearwards, in order to concentrate, when the packing is subjected to compression, the compressive stresses in a front radially inner part, of the heel, thus ensuring the limiting of the expansion of the said heel radially outWards; . - the radially outer surface of the body has a shape generally converging towards the rear extremity of the packing; - a front part, without a recess, of the radially outer surface of the body diverges towards the front, this part being intended to bear against a. corresponding part of the reaction surface of the counterflange when the packing is subjected to compressoin; - at least two parts, without a recess, of the radially outer surface of the body diverge towards the front, a rear part and the said front part respectively,, and the said front part diverges more markedly than the rear part, these two parts being intended to bear against corresponding parts of the reaction surface of the counterf larige when the packing is; subjected to compression? •- the radially inner surface of the heel has at least two radial projections forming lugs for the axial positioning of the device on the smooth end, these lugs being intended to abut against the axial extremity of the smooth end before the packing is subjected to compression; •- the device comrpises at least two metallic blocking inserts arranged in a rear extremity portion of the body, each inserr. having a radially inner surface, of which a catching relief is intended to bear on the radially outer surface of the smooth end in order to lock the joint between the two pipeline elements, when the packing is subjected to compression; - at least one rear frontal recess for the expansion of the elastomer of t.'h.e compressed packing is formed between the inserts in a re,1:7 extremity surface of the body; and - at least one blocking insert has on a radially outer surface a substantially radial projection, this projection being intended to cooperate with a substantially radial abutment part of the reaction surface of: the counterflange in order to limit the radial displacement of the insert when the packing is subjected to compression. The subject of the invention is also a leaktight joint between pipeline elements, in particular pipes., comprising a smooth end of ia first pipeline element, a flange of a second pipeline element,, and a counterfletnge surrounding the smooth end and secured to the flange, characterized in that it comprises a device as defined above, the ssaid radially outer .surface of the body bearing on a reaction surface of the counter flange, the said radially inner surface of the body bearing on the radially outer surface of the smooth end, and the said front extremity surface of the heel bearing on the flange, thereby ensuring the leak-tightness of the joint between the two pipeline elements. The subject of the invention is finally a. leaktight and locked joint between pipeline elements, in particular pipes, comprising a smooth end of a first pipeline element, a flange of a second pipeline element, and a counterflange surrounding the smooth end and secured to the flange, characterized in.that it comprises a device as defined above, the said radially outer surface of the packing bearing on an inclined-reaction surface of the counterflange, the said radially inner surface of the body as well as the catching reliefs of the inserts bearing on the radially outer surface of the smooth end, and the said front extremity surface of the heel bearing on the flange, thereby ensurrinq the leaktightness and tha locking of the joint between the two pipeline elements. The invention will be better understood on reading the description which follows, given purely by way of example and with reference to the accompanying drawings, in which: - Figure. l, is a longitudinal sectional view of a joint between pipes comprising a device according to the invention, the upper half-view showing the joint before compression of the packing, and the lower half-view showing the joint, after compression of the packing, - figure 2 is an enlarged view of the encircled part II of Figure I,, - Figure 3 is a partial longitudinal sectional view, illustrating the longitudinal section, before compression, of a variant, of the device of Figure 1, - 'figure 4 is a view anaologus to Figure 1, illustrating a joint between pipes comprising the device of Figure 3, - figures 5 to 7 are partial longitudinal sectional views, each illustrating the longitudinal section, before compression, of a variant, of the device: of Figure 1, - Figure 8 is a longitudinal sectional half-view of a second embodiment of a device according to the invention, this view being taken in a diametral plane passing through a blocking insert and a lug for the positioning of the device, - Figure 9 is a view analogous to Figure 1, illustrating a joint between pipes which is equipped with the device of Figure 8' - Figure 10 is a view analogous to Figure 8, illustrating a variant of the device of this Figure 8, and - Figure 11 is a longitudinal sectional view of a variant of an insert for a device of one of Figures 8 to 10. The upper half-view of Figure 1 shows a smooth end 1 or male end of a first pipe 2 and a flange 3 of a second pipe 4 which are ready to be joined. These pipes, arranged substantially coaxially, may be especially successive pipes of a pipeline, in particular pipes made of cast iron, each pipe comprising a smooth end l at one extremity and a flange 3 at its othisr extremity, The flange 3 extends radially from the rear oxtremity 5 (on the left in Figure 1) of the pipe 4 and it. is pierced with orifices 6 which are regularly distributed angularly. A device 7, consisting of a packing 8 and of a known continuous metallic ring 9, surrounds, the front extremity part 10 (on the right in Figure l) of the smooth end L. A counterflange 11, surrounding the smooth end 1, is initially located to the rear of the packing 8. This counter flange 11 comprises a substantially frusitoconical rear part 12 which diverges towards the front and is substantially coaxial with the pipe 2. The part 12 is continued axially towards the front by an intermediate part 12A which diverges less markedly. Projecting radially outwards on the front extremity of the intermediate part is a collar or web 13 which is pierced with orifices 14 which are regularly distributed angulsirly and located opposite the orifices 6. Bolt connections (not shown) pass through the oppositely located orifices 6 and 14. The packing 8 is made of elastomer and comprises an annular body 15 equipped at its front extremity with an annular heel. 16 of substantially rectangular section. As is apparent from Figure 2, the cylindrical radially inner surface 17 of the heel 16 continues the cylindrical radially inner surface 18 of the body 15, so that the radially inner surface 19 of the packing 8 is cylindrical. This surface 19 bears against the radially outer surface 20 of the smooth end 1. A radially outer annular part 21 of the heel 16, protrudes radially outwards from the radially outer surface 22 of the body 15. This surface 22 is connected to the radially outer surface 23 of the heel 16 by an annular radial shoulder 24. An annular groove 25 which opens onto the shoulder 24 is formed in the part 21. The inside diameter of the groove 25 is substantially less than the diameter of the surface 22. at the front of the body 15. The surface 22 of the body 15 has a generally frustoconioal shape converging towards the rear extremity of the packing 8, with an angle of convergence which is substantially constant with respect to the axis of the packing 8. Three identical annular recesses 26, of semicircular section and axially offset with respect to one another, are formed in the surfacs 22. Internally, the rear part 12 of the counterflange 11 has a surface 27 which converges towards the rear extremity 28 of the counterflange 11. The intermediate part 12A has an inner surface 27A substantially conjugate with the surface 22. The surfaces 27 and 27A form a reaction surface. The joining of the two pipes will now be described. In the position of readiness, as shown in the upper half-view of Figure 1, the inner face 27A of the intermediate part 12A of the counterflange is located in contact with a rear part of the surface 22 of the body 15, the packing 8 not being compressed. The edge 29 of the smooth end 1 is substantially plane and in contact with the rear surface 30 of the flange 3. The front surface 31 of the heel 16 is substantially plane and the packing 8 is positioned on the smooth end 1 in such a way that the surface 31 is in contact with the surface 30, which is also plane, of the flange 3. The axial play.between the two pipes 2 and 4 is therefore zero or virtually zero. The inside diameter of the rear extremity 28 fo the counterflange 11 is very slightly greater than the outside diameter of the smooth end 1, the diametral play between the counter flange 11 and the smooth end l then being minimal. The inner surface 27, 27A of the aounterf lange 11 delimits a compression chamber 32 around the smooth end 1. In order to join the pipes 2 and 4 in a leaktight manner, the bolt connections which connect the counterflange 11 to the flange 3 are tightened, which brings about the displacement of the counterflange 11 towards the front. The lower half-view of Figure l shows the jioned pipes 2 and 4 after tightening of the bolt connections. The packing 8 is then compressed between the flange 3 and the counterflange 11, the deformed surface 22 bearing on the reaction surface 27, 27A, the surface 19 being pressed onto the surface 20 of the smooth end and the surface 31 of the heel 16 bearing on the surface 30 of the flange 3. The body 15 is then practically entirely lodged in the sealing chamber 32, the recesses 26 then being no longer visible, following the deformation of the elastomer. The recesses 26 have provided spaces for the expansion of the elastomer when the packing 8 is subjected 1:o compression, thus permitting the body 15 to be lodged practically entirely in the chamber 32. The web 31 has therefore been able to be obrught as close to the flange 3 as possible, thus making it possible to limit the free space aveilable for the radial expansion of the heel. 16 when the elastomer is subjected to compression. This radial expansion has also been limited by the ring 9 which radially retains the part 21 of the heel 16. The joining conditions shown, that is to say when the axial and diametral play are minimal, are the most harsh in which to be able to ensure good leaktightness. This is because, in these conditions, there is a relatively large quantity of elastomer for a small expansion space. More precisely, by using packings having bodies without recesses, it is found, in the same conditions, that the body 15 does not penetrate totally into the chamber 32. The distance between the web 13 and the flange 3 is therefore greater than with the device of Figure 1, and an uncontrolled flaring of the heel 16 outwards is then found, in particular when the pipes 2 and 4 are pressurized, which may cause leaks between the surface 31 of the heel and the surface 30 of the flange. In contrast, such flaring, when there is presisurization, is largely prevented here by the combined effect of the recesses 26 and the ring 9 in the device of Figure 1. With the device of Figure 1, the leaktightnesss is therefore perfect when the diametral and/or axial play are/is minimal, and it remains satisfactory in the case where these plays are substantial. Moreover, the device of Figure 1 is particularly economical and easy to realize, since it comprises a packing 8 made of a single piece of elastomer to which there is attached a metallic ring 9 retained in the groove 25. It has also been noted that the recesses 26 facilitate, on the one hand, the joining of the pipes by decreasing the friction of the packing on the isurface 27, 27A of the counterflange, and, on the other hand, tho demounting of the counterflange 11, the packing 8 being detached more easily from the latter in the presence of the recesses 26. The ring 9 is more generally a rigid ring adapted to ensure the limiting of the radial expansion of the heel outwards. It nay also be replaced by an annular helical spring lodged in the groove 25 which forms an open cavity, or embedded in the heel 16, In a variant, the heel may be overmoulded on the rigid ring or on the spring. Figure 3 shows a partial longitudinal sectional view of a variant of the device of Figure 1. This device consists solely of a packing 8, which packing is distinguished from the packing of Figure 1 solely by the shape of its heel 16. Its heel 16 continues the entire body 15 of the packing 8 towards the front, without radial projection outwards, that is to say the radially outer surface 33 of the packing 8 is of a shape which generally converges towards the rear with an angle of convergence which is substantially constant with respect to the axis of the packing 8, from its rear extremity to its front extremity. The front flank 34 of the front recess 35 slopes substantially reotilinearly, thus increasing the axial dimension of this recess 35 as compared with the two other recesses 26 of semicircular section. The surface 31 of the heel 16 is inclined with respect to the radial plane by a substantially constant angle α, this surface 31 being substantially frustoconical and converging towards the front extremity of the heel. This latter feature makes it possible to obtain a rigidification of the front radially inner part 36 of the heel 16 when the surface 31 bears on the surface 30 of the flange 3 as shown in the lower half-view of Figure 4, Before the joining, as shown in the upper half-view of Figure 4, only the radially inner edge 37 of the surface 31 is in contact with the surface 30 of the flange 3. During the tightening of the bolt connections which connect the flange 3 and the counterflange 11, the part 36 of the heel 16 is compressed, whereas the rest of the surface 31 progressively bears against the surface 30 of the flange 3. After tightening of the bolt connections, the compressive stresses are therefore concentrated in the part 36 of the heel 16. When the pipes 2 and 4 are pressurized, this part 36 therefore offers greater resistance to the pressure of the fluid tending to flare the heel 16 outwards than in the case of a conventional packing 8 without a member for limiting the radial expansion of the heel and with a substantially radial surface 31. Moreover, this configuration of the surface 31 tends to guide the deformation of the elastomer of the heel 16 radially inwards during the tightening of the bolt connections, in particular when the axial play between the smooth end 1 and the flange 3 is not zero. The measure of the angle a may be typically 15°. Figure 5 illustrates another variant of the device 7, which is distinguished from that of Figure 3 solely in that two recesses 26 are formed on the surface 22 of the body 15 and in that the surface 22 has, from the front, two successive parts .38 and 39 of shapes which generally converge towards the rear and have different angles of convergence with respect to the axis of the packing 8. Thus, the front part 39 is more convergent than the rear part 38, the junction between the two parts 38 and 39 being at the front recess 26. These two parts 38 and 39 are intended to boar on rear and front parts of roughly corresponding inclinations of the intermediate surface 27A of the counterflange 11. During the tightening of the bolt connections, the part 39 bearing on the surface 27A of the counterflange 11 forces the heel 16 radially inwards and participates, after tightening, with the surface 31 of the heel 16, in the limiting of the expansion of the heel 16 radially outwards, thereby improving the leaktightness of the connection between the heel 16 and the flange 3. Figure 6 illustrates another variant of the device, which is distinguished from that of Figure 3 solely in that annular recesses 40 are provided both on the surface 22 and on the surface 18 of the body of the packing 8. The recesses 40 are deeper and narrower than the recesses 26 of the packing 8 of Figure 2. The recesses 40 are axially offset with respect to one another, the packing 8 thus having a bellows configuration, Figure 7 presents another variant of the device Which is distinguished from that shown in Figure 3 in that a single annular recess 41 is formed in the body 15, on the surface 18 of the latter. This recoss 41 defines an annular cavity 42 closed at least partially towards the rear by a part 43 of the packing 8 forming an annular lip. A split toric ring 44 made of hard plastic or of metal is lodged in the cavity 42 by bearing on the lip 43. When the packing is subjected to compression, the ring 44 is pressed onto the lip 43 by the radially outer part of the body •15, and the ring thus keeps the lip 4;3 bearing or the surface 20 of the smooth end 1 in order to ensure good leaktightness of the joint between the pipes 2 and 4. Simultaneously, the recess 41 provides an expansion volume for the elastomer, which closes the cavity 42 around the ring 44, thereby permitting the virtually complete penetration of the body 15 into the sealing chamber 32. Figure 8 illustrates another embodiment of the device, which is distinguished from the device 7 of Figure 1 in that it comprises metallic locking inserts 45 embedded in a rear extremity portion 46 of the body 15 of the packing 8. These inserts 45 are blocks which are regularly distributed angularly and are peripherally connected by the body 15, They have an exposed radially inner surface 47 equipped with catching teeth 48, these teeth 48 being intended to bite into the surface 20 of the smooth end 1 in order to lock the joint between the pipes 2 and 4, The radially outer surface 49 of the portion 46 is more markedly convergent than the surface 22 of the body 15, Recesses 50 are formed in the rear frontal surface 51 of the body 15 between the inserts 45, so that this surface .51 has axial offsets which advance axially substantially as f.ar as the level of the rear extremity of each insert 45. The surface 17 of the heel 16 has, at the front, identical projections 52 which are regularly distributed angularly. These projections 52 are blocks of trapezoidal section, of which the front frontal surface 53 continues the radial surface 31 of the heel 16 and of which the rear frontal surface 54 is inclined radially outwards and axially rearwards. These projections 52 form positioning lugs which enable the automatic preservation of a minimal spacing between the front extremity 10 of the smooth end 1 and the surface 30 of the flange 3 before tightening of the bolt connections, as shown in the upper half-view of Figure 9. In contrast to the configuration of Figure l, the axial play between the pipes 2 and 4 is not therefore minimal, During the joining (Fig. 9), the packing 8 is slipped onto the smooth end l, the surfaces 54 of the lugs "52 bearing on the front extremity of the smooth end 1, which is chamfered, and the surface 31 of the heel 16 and the surfaces 53 of the lugs 52 bearing on the surface 30 of the flange 3. It is necessary to preserve such a minimal spacing before tightening so that the leaktightness can be ensured independently of the locking. In fact, the locking between the pipes 2 and 4 takes place during the clamping of the counterflange 11 onto the flange by cooperation between the surface 27 of this counter flange 11 and the radially outer surfaces of the inserts! 45, which are thus pushed axially towards the front and radially inwards, In addition to the automatic positioning of the packing 8 on the smooth end l, the lugs 52 also enable the correction of any warping of the edge 29 of the smooth end 1. The fact that the surfaces 54 are inclined enables the optimization of the assembly with the edge 29 of the smooth end l chamfered or not. Thus, if the edge 29 of the smooth end l is chamfered, the surfaces 54 of the lugs 52 cooperate with the chamfer of the edge 29 as shown in Figure 9, the chamfer of the edge 29 of the smooth end thus providing, between the lugs, an additional expansion space for the elastomer when the diametral play is minimal, The presence of the recesses 50 between the inserts 45 enables the improvement of the leaktightness of the joint at the inserts 45 and the facilitation of the disassembly of the joint. Thus, when the diametral play is minimal, as shown in Figure 9, these recesses 50 prevent the formation of bulges resulting frow the flow of the elastomer outside the countorflange 11 (to the rear of the latter). These recesses 50 consequently facilitate the demounting of the counterflange 11, which is easier in the abserce of such flow bulges, and also increase the possibility of angular deviation of the smooth end l with respect to the flange 3. Moreover, these recesses 50 prevent the undulation of the elastomer, when the diametral play is minimal, at the surface 22 of the packing and in the vicinity of the inserts 45, such an undulation potentially leading to sealing defects and causing the inserts to corrode as a result of the outside environment. The recesses 26 facilitate and improve the locked joining of the pipes by limiting the friction between the body of the packing 8 and the counterflange 11. Figure 10 shows a longitudinal sectional half-view of a variant of the device of Figure 8, in which the ileel 16 and the surface 22 of the packing have a configuration similar to those of the packing of Figure 5. Thus, the device of Figure 10 is essentially distinguished from that of Figure 8 in that the surface 31 of the heel 16 is inclined with respect to the radial plane as in F:Lgs. 5 to 7, in that the surface 22 of the packing 8 has, in front of the inserts, two parts 38 and 39 with different angles of convergence with respect to the axis of the packing, as in Fig. 5, and in that the front surfaces 53 of the lugs 52 are situated to the rear of the front edge 37 of the surface 31 of the heel 16, Moreover, only two annular recesses 55 are formed on the surface 22 of the body 15. The junction between the two parts 38 and 39 is at the front recess 55. The front flanks 56 of the recesses 55 are inclined substantially rectilinearly, so that the axial length of these recesses 55 is greater than that of the recesses 26 of the packing of Figure 8. The flank 56 of the front recess 55 continues the part 39 of the surface 22. In a manner analogous to the variant of Figure 4, the inclined surface 31 of the heel 16 makes it possible to ensure a rigidification of the heel during the clamping of the packing by the counterflange 11. in combination with the part 39 of the surface 22, this inclined surface 31 ensures the limiting of the radial expansion of the heel 16 when the pipes 2 and 4 are pressurized. Moreover, the surface 31 guides the expansion of the elastomer radially inwards when the packing 8 is subjected to compression. Furthermore, the spacing between the surfaces 53 of the lugs 52 and the edge 37 of the surface 31 of the heel 16 makes it possible to form an additional free space for the expansion of the elastomer when the packing 8 is subjected to compression. Figure 11 is a longitudinal sectional view of an insert 45 which is adapted to be used in a device similar to those of Figures 8 or 10, in the case where the smooth erd 1 is made of plastic. The radially outer surface 57 of the insert 45 has, at the front, a radial projection 58 connected to the surface 57 by a substantially radial abutment shoulder 59. Such inserts 45 areintended to be embedded in the portion 46 of a packing 8, as shown in figures 8 to 10. The shoulder 59 of each insert 45 of such a packing is intended to cooperate with a corresponding substantially radial part of the reaction surface 27 of the counterflange 11, when the packing is subjected to compression. Thus, the radial displacement of the inserts 45 during the tightening of the counterflange is controlled, thereby in particular avoiding too deep a radial penetration of the inserts into the smooth end l, potentially leading to damage, and even perforation, of the smooth end 1. CLAIMS 1. Device (7) for the joint between a smooth end (1) and a flange (3) of two pipeline elements (2,4), comprising an axial- compression packing (8) made of elastomer, this packing comprising a body (15) for bearing against a counterflange (11) for compression of the packing (8) and, at the front of this body (15) and .'integral with the latter, a heel (16) for bearing against the flange, a radially outer surface (22) of the body being intended to bear on a reaction surface (27, 27A) of the counterflange (11), a radially inner surface (18) of the body (15) being intended to bear on the radially outer surface (20) of the smooth end (l), and a front extremity surface (31) of the heel (16) being intended to bear on the flange (3) in order to ensure the ieaktightness of the joint between the two pipeline elements (2,4), characterized in that the body (15) has at least one recess (26,35,40,41;26,55) for the expansion of the elastomer of the compressed packing, and in that the device (7) is provided with a means for limiting the expansion of the heel (16) radially outwards. 2. Device according to Claim 1, characterised in that the recess is an annular recess (26,35,40,41;26,55) formed on the radially inner surface (18) or on the radially outer surface (22) of the body (15). 3. Device according to Claim 2, characterised in that the recess (41) is formed on the radially inner surface (18) of the body (15), this recess (41) defining a cavity (42) closed at least partially by a part of the packing forming an annular lip (43), and in that the device (7) comprises a member (44) for holding the lip (43) on the radially outer surface (20) of the smooth end (1), this member (44) being lodged in the said cavity (42). 4. Device according to Claim 3, characterised in that the said holding member is a split toric ring (44). 5. Device according to any one of Claims 2 to 4, characterized in that the recess (40) is formed on the radially inner surface (18) of the body (15), in that at least one other annular recess (40) is formed on the radially outer surface (22) of the body (15), and in that these two recesses (40) are axially offset with respect to one another. 6. Device according to any one of Claims 1 to 5, characterized in that the means for limiting the expansion of the heel is a rigid, in particular metallic, ring (9), arranged in a radially outer part (21) of the heel (16). 7. Device according to any one of Claims 1 to 5, characterized in that the means for limiting the expansion of the heel is an annular spring arranged in a radially outer part of the heel. 8. Device according to any one of Claims 1 to 7, characterized in that the said front extremity surface (31) of the heel (16) has at least one inclined part which diverges rearwards, in order to concentrate, when the packing (8.) is subjected to compression, the compressive stresses in a front radially inner part (36) of the heel, thus ensuring the limiting of the expansion of the said heel radially outwards. 9. Device according to any one of Claims 1 to 8, characterized in that the radially outer surface (22) of the body (15) has a shape generally converging towards the rear extremity of the packing (8). 10. Device according to any one of Claims 1 to 9, characterized in that a front part (39?39), without a recess, of the radially outer surface (22) of the body (15) diverges towards the front, this part being intended to boar against a corresponding part of the reaction surface •'(l!7,27A) of the counterflange (11) when the packing (8) is subjected to compression. 11. Device according to Claim 10, characterized in that at least two parts (38,39;38,39), without a recess, of the radially outer surface (22) of the body diverge towards the front, a rear part (38) and the said front part (39) respectively, and in that the said front part (39) diverges more markedly than the rear part (38), these two parts being intended to bear against corresponding parts of the reaction surface (27, 27A) of the counterflange (11) when the packing (8) is subjected to compression. Device according to any one of Claims 1 to 11, characterized in that the radalily inner surface (r17) of the heel (16) has at least two radial projections (52) foming lugs for the axial positioning of the device (7) on the smooth end (1), these rags (52) being intended to abut against the axial extremity (10) of the smooth end (1) before the packing (8) is subjected to compression. 12. Device according to any one of Claims; 1 to 12, characterized in that it comprises at least two metallic blocking inserts (45) arranged in a rear extremity portion (46) of the body (15), each insert (45) having a radially inner surface (47), of which a catching relief (48) is intended to bear on the radially outer surface (20) of the smooth end (1) in order to locK the julut, between the two pipeline elemente (3,4) vm®n tho packing (&) is subjected to compression. 14. Device according to Clain 13, characterized in that at least one rear frontal recess (BO) for the expansion of the elastomer of the compressed packing (8) is formed between the, inserts (45) in. a raer extremity 'surface (51) of the body (15). 15. Device; according to Claim 13 or 14, characterized in that, at least, one blocking insert (45) has on a radially outer surface (57) a substantially radial projection (58), this projectior (58) being intended to cooperate with a substantially radial abutment part of the reaction surface (27 ,27A) of the counterflange (11) in order to limit the radial displacement of the ;.nstiit (45) when the packing (8) is subjected to compression, 16. Leaktight joint between pipeline elements,, in particular pipes, comprising a smooth end (1) of a first pipeline element (2),. a flange (3) of a .second pipeline element .(4), and a counter flange (11) surrounding the smooth end (1) and secured to the flange (2;), characterized in that it comprises a device (7) according to any one of Claims 1 to 12, the said radially outer surface (22) of the body (15) bearing on a reaction surface (27,27A) of. the counter flange (11), the said radially inner surface (18) of the body (15) bearing on the radially outer surface (20) of the smooth end (1), and the said front extremity surface (31) of the heel (16) bearing on the flange (3), thereby ensuring the leaktightness of the joint; between the two pipeline elements- 17. Leaktight and locked joint .between pipeline elements, in particular pipes, comprising ;a smooth end (1) of a first pipeline element (2), a flange (3) of a second pipeline element (4), and a counterflange (11) surrounding the smooth end (1) and secured to the flange (3), characterized in that it comprises a device (7) according to any one of Claims 13 to 15, the said radially outer surface (22) of the packing (8) bearing on an inclined reaction surface (27,27A) of the counterflange (11), the said radially inner surface (18) of the body (15) as well as the catching .reliefis (48) of the: inserts (45) bearing on the radially outer surface (20) of the smooth end (l), and the said front extermity surface (31) of the heed (16) bearing on the flange (3), thereby ensuring the leaktightness and the locking of the joint: between the two pipeline elements. 18. Device for the joint between a smooth end and a flange of two pipeline elements substantially as herein described with reference to the accompanying drawings.

Documents:

2164-del-1998-abstract.pdf

2164-del-1998-claims.pdf

2164-del-1998-correspondence-others.pdf

2164-del-1998-correspondence-po.pdf

2164-del-1998-description (complete).pdf

2164-del-1998-drawings.pdf

2164-del-1998-form-1.pdf

2164-del-1998-form-13.pdf

2164-del-1998-form-19.pdf

2164-del-1998-form-2.pdf

2164-del-1998-form-3.pdf

2164-del-1998-form-4.pdf

2164-del-1998-form-6.pdf

2164-del-1998-gpa.pdf