FR3011307A1 - CONNECTING DRIVE, INSTALLATION AND METHOD USING SUCH DRIVING - Google Patents

Abstract

Fluidic connecting pipe comprising a body extending along a central longitudinal axis (15, 9, 16), the connecting pipe (1) being provided with two end sections (5, 6), characterized in that the connection pipe (1) comprises a housing (10) arranged between the two end sections (5, 6) and fluidly communicating with the two sections (5, 6), the housing (10) being formed of two plates (7, 8) to be joined to each other, the two end sections (5, 6) being rigidly secured respectively to the two plates (7, 8) and in that the two sections (5 , 6) are arranged transversely offset from the central longitudinal axis (9) of the housing (1).

Description

The present invention relates to a connecting pipe and an installation and a method of connection using such a pipe. The invention more particularly relates to a fluidic connection pipe intended to be interposed between the spaced ends of two pipes, the connecting pipe comprising an oblong body extending in a longitudinal direction defining a direction of fluid flow in the pipe, the connecting pipe being provided with two end sections. The invention relates to a device for making the junction between the pipes of two separate equipment. In particular, the invention particularly relates to a means of fluidically connecting two cryogenic circuits (two or more rigid pipes) belonging to separate installations and which can be carried out by different manufacturers. In these situations, the pipes to be connected may be more or less well aligned and may also have different dimensions (including diameter). According to a known technique, the operators measure the differences in alignment of the two pipes to be connected according to the three dimensions (x, y, z) and convert these differences into angles in order to make bent pipe portions catching these differences. That is to say that the operators cut portions of tubes at defined angles to achieve by welding a partially bent pipe providing a connection despite the misalignment. In particular, the operators must adjust the cuts of the parts to overcome the uncertainties of the measurements and machining and take into account the shrinkage of welding in order to be able to perform the junction welds.

This very artisanal solution is relatively long and expensive. In addition, this solution may be incompatible with certain codes or building standards or require validation by calculations of the structure after completion. Moreover, this solution requires manual welding, controls of radio welds, and generate risks of leakage. In addition, in certain situations this solution poses difficulties to inert the pipes during welding of the pipes. An object of the present invention is to overcome all or part of the disadvantages of the prior art noted above.

To this end, the pipe according to the invention, which moreover conforms to the generic definition given in the preamble above, is essentially characterized in that the connecting pipe comprises a casing disposed between the two end sections, the housing extending along a central longitudinal axis parallel to the longitudinal direction of the pipe and fluidly communicating with the two end sections, the housing being formed of two separate plates intended to be assembled one to the other; other, the two end sections being rigidly secured respectively to the two plates and in that the two end sections are arranged transversely offset with respect to the central longitudinal axis of the housing, that is to say that the central longitudinal axes of the two end sections are each spaced apart by a respective distance from the central longitudinal axis of u case. Furthermore, embodiments of the invention may comprise one or more of the following characteristics: the end sections are rectilinear; in the assembled position of the two plates, the central longitudinal axes of the two end sections are parallel, - in the assembled position of the two plates, the central longitudinal axes of the two end sections are parallel to the central longitudinal axis of the housing, - the two plates are assembled edge to edge in a plane of joint perpendicular to the axis longitudinal center of the housing, - the assembly edges of the two plates are symmetrical around the central longitudinal axis of the housing and at multiple angular positions of assembly of a plate relative to the other plate about the longitudinal axis central housing, according to the angular position of a plate relative to the other plate around the central longitudinal axis of the housing, the distance transver (in millimeters) between the central longitudinal axes of the two sections is between a minimum spacing and a maximum spacing, the minimum spacing being between zero and (max (D1, D2) - Min (D1, D2)) and maximum spacing is equal to D1 + D2, with D1 and D2 being the respective transverse spacing distances in millimeters of the central longitudinal axes of the two sections relative to the central longitudinal axis of the housing, - the two end sections are cylindrical and have diameters equal or different, - the two previously separated plates are assembled in a relative position determined by welding, - one of the end portions comprises a flexible and elastic portion located between the housing and the end end of said section, the respective transverse spacing distances (D1, D2) of the central longitudinal axes of the two sections relative to the central longitudinal axis of the housing are equal (D1 = D2), - the flexible and resilient portion comprises a bellows, - the two pipes connected to each other via a connecting pipe are rectilinear and have longitudinal axes parallel to the longitudinal direction, the longitudinal axes both pipes being offset in a direction transverse to the longitudinal direction. The invention may also relate to an installation comprising at least one cryogenic fluid transfer rigid circuit comprising at least one fluid transfer pipe, said at least one inner pipe comprising two distinct straight pipe portions, the two inner pipe portions having respective ends spaced and vis-à-vis in a longitudinal direction, the two ends of the pipes being connected to each other via a connecting pipe according to any of the above characteristics or below. According to other possible embodiments: the circuit is of the jacketed type, that is to say having an outer tubular casing housing, in its internal volume intended to be evacuated, the at least one pipe, the two ends of the pipes connected to each other via a connecting pipe are not aligned in the longitudinal direction. The invention may also relate to a method of fluidic connection of two ends of pipes extending along axes respective longitudinal lines via a connecting pipe disposed between said two separate ends, the connecting pipe being in accordance with any of the above characteristics or hereinafter, the method comprising: - a step of positioning a first section end of the connecting pipe so as to coincide with a first end of pipe, - a step of relative displacement atif of the two plates in a so-called "concordance" position to also position the second end section of the connecting pipe so as to coincide with the second pipe end, - a step of locating the said position of concordance between the two plates, - a step of rigid assembly of the two plates in said position of concordance, - a step of rigid assembly of the two end sections respectively at the two ends of pipes According to other possible features: - the stage rigid connection of the two end sections respectively at the two ends of the pipe is made by welding, the ends of the end sections being each provided with a mounting insert projecting beyond said end portion, each insert having the shape of a ring intended to form an internal screen during welding at the junction between the end of the pipe and the end section, - in disassembled and unconstrained position, the connecting pipe provided with the inserts has a dimension in the longitudinal direction which is greater than the spacing between the two pipe ends to be connected, the pipe connection comprising an elastic portion, the positioning of the connecting pipe to coincide with the two ends of the pipe with the two pipe ends comprising a longitudinal contraction step of the elastic portion of the connecting pipe.

The invention may also relate to any alternative device or method comprising any combination of the above or below features. Other particularities and advantages will appear on reading the following description, with reference to the figures in which: FIG. 1 represents a perspective view, schematic and partial, of two sets of cryogenic lines to be connected; FIG. 2 is a diagrammatic and partial perspective view of the pipe assemblies of FIG. 1 connected via connecting pipes according to a possible embodiment of the invention; FIG. 3 is a longitudinal sectional view of FIG. a detail of FIG. 2 illustrating two pipe ends connected via a connecting pipe according to a first embodiment of the invention; FIGS. 4, 5 and 6 represent perspective, schematic and partial views of the pipeline assemblies of FIG. 1 illustrating respectively three stages of successive assembly of a pipe circuit; FIG. A schematic and partial perspective view illustrating another possible embodiment of a connecting pipe of the invention, - Figures 8 and 9 are longitudinal sectional views of the pipe of Figure 7 and illustrating respectively two different configurations of cross-clearance play. FIG. 1 represents an example of two cryogenic circuits intended to be connected to one another. Each circuit comprises several pipes 2, 3 for transporting cryogenic fluid (for example helium or nitrogen at cryogenic temperature). Conventionally, these pipes 2, 3 (internal) are intended to be housed under vacuum in an envelope (external). Conventionally, the pipes 2, 3 are generally rectilinear, rigid or semi-rigid (that is to say can integrated flexible and / or elastic portions for catching games or relative displacements). The pipes 2, 3 are composed for example mainly of austenitic steel, copper stainless steel or aluminum alloy. The example shown in FIG. 1 comprises several pairs 2, 3 of internal pipes to be connected fluidically. Of course, the invention can also be applied to an installation comprising a single pair of internal pipes 2, 3 to be connected. The following description will detail the connection of two ends 12, 13 of pipes 2, 3 forming, after connection, a continuous pipe.

For the sake of brevity the connection of the other pairs 2, 3 of pipe will not be described in detail (the other pairs of pipes can be connected according to the same principle if necessary). The ends 12, 13 spaced apart from two pipes 2, 3 to be connected are spaced apart for example by a distance of between 150 mm and 500 mm in a longitudinal direction (x). In addition, the longitudinal axes of the two pipes 2, 3 may be parallel to the longitudinal direction x. Conventionally, the ends 12, 13 of the two pipes 2, 3 are shifted transversely (in yz plane transverse to the longitudinal direction x).

That is to say that the longitudinal axes of the pipes 2, 3 to be connected are not aligned on the same axis but are eccentric. This connection is possible without the disadvantages of the prior art via a conduit 1 for fluid connection described below. The connecting pipe 1 illustrated in FIGS. 2 and 3 (first embodiment) and in FIGS. 7 to 9 (second exemplary embodiment) comprises an elongated body of generally tubular shape extending in a longitudinal direction x defining a direction of fluid flow in the pipe 1. The pipe 1 is provided with two end sections 5, 6 (for example cylindrical tubes) intended to be fixed respectively at the two ends 12, 13 of pipes 2, 3. The sections 5, 6 end are for example rectilinear. The two end portions 5, 6 are preferably cylindrical and have equal or different diameters according to the characteristics of the pipes 2, 3 to be connected.

The body of the connecting pipe 1 also comprises a portion forming a housing 10 located between the two end sections 5, 6. The housing 10 extends along a central longitudinal axis 9, which in this example is parallel to the longitudinal direction x of the connecting pipe 1. The inside of the housing 10 communicates fluidly with the two end sections 5, 6. The housing 10 is composed of two separate plates 7, 8 intended to be assembled to one another. For example each plate 7, 8 in the form of a half-shell or a half-casing. The two end portions 5, 6 are rigidly secured respectively to the two plates 7, 8 (for example monoblocs or by welding or any other appropriate means). Preferably the two plates 7, 8 are identical. The two end sections 5, 6 are furthermore arranged transversely offset with respect to the central longitudinal axis 9 of the casing 1. That is to say, the central longitudinal axes 15, 16 of the two sections 5, 6 end are each spaced apart by a distance D1, D2 (see Figure 3) respective determined with respect to the central longitudinal axis 9 of the housing 10. In this way, according to the relative positions of the two plates 7, 8, the central longitudinal axes 15, 16 of the two end sections 5, 6 can be arranged in an aligned and merged manner (see FIG. 8) or in a transverse manner separately (see, for example, FIG. 9 or FIGS. are shifted transversely to the longitudinal axes). As described in more detail below, the two independent plates 7, 8 relative to each other can be assembled in a determined position corresponding to determined transverse spacing of the end sections 5, 6. This makes it possible to easily adapt the spacing between the end sections 5, 6 to the spacing of the ends 12, 13 of pipes to be connected. For example, the two plates 7, 8 are assembled edge to edge (identical circular edges) in a plane of joint 11 perpendicular to the central longitudinal axis 9 of the housing 10. Thus, according to the angular position of a plate 7, 8 relative to the other plate 8, 7 around the central longitudinal axis 9 of the housing 10, the transverse distance between the longitudinal axes 15, 16 central of the two sections 5, 6 can be between a minimum spacing and a maximum spacing .

The minimum spacing is, for example, equal to zero (see FIG. This minimum spacing may be zero when D1 = D2 (see Figure 3 or Figure 8). If D1 is not equal to D2 in the embodiment of Figure 3 the minimum spacing is equal to (max (D1, D2) - Min (D1, D2)). The maximum spacing is, for example, equal to D1 + D2 (see FIG. 9), with D1 and D2 being the respective transverse spacing distances of the central longitudinal axes 15, 16 of the two sections 5, 6 with respect to central longitudinal axis 9 of the housing 10 (see Figure 3 also). The maximum spacing is for example between 20 mm and 75 mm, for example 25 mm. The two plates 7, 8 previously separated can be assembled in a relative position determined by welding or any other appropriate means (gluing, riveting ...). Of course, the circular shape of the edges of the plates 7, 8 to be assembled can be replaced by any other geometric shape allowing the assembly edges of the two plates to assemble in multiple angular positions (several discrete positions for example). As illustrated in the figures, in the assembled position of the two plates 7, 8, the central longitudinal axes 15, 16 of the two end sections 5, 6 are preferably parallel. Of course, depending on the configuration of the pipes 2, 3 to be connected, the central longitudinal axes 15, 16 of the two end sections 5, 6 can be inclined with respect to each other in the assembled position. For example, the longitudinal axis 15, 16 central of at least one end section 5, 6 may be inclined relative to the central longitudinal axis 9 of the housing 10. The assembly of a connecting pipe according to the Embodiment of Figures 6 to 8 may include the following steps. - Place a first end section 5, 6 (with its plate 7, 8) aligned with a first end 12, 13 of pipe 2, 3, - place the second end portion 6, 5 aligned with a second end 13, 12 of pipe 3, 2. This is obtained by displacing (rotation for example) relatively the two plates 7, 8 in the so-called matching position (alignment of the sections 5, 6 with respectively the pipes 2, 3) .

This position of concordance can be identified or marked or maintained by a weld point so as to then weld the two plates 7, 8 in this position of concordance. The connecting pipe 1 thus obtained can be reinstalled in the circuit and the ends of the end sections 5, 6 can be welded to the respective pipes 2, 3 (the connection pipe 1 at a determined length corresponding to the spacing L between the two lines 2, 3 to be connected). As illustrated in the embodiment of FIG. 3, in order to carry out the welding of the end sections 5, 6 at the ends 12, 13 of lines 2, 3, the ends of the end sections 5, 6 can be provided with each of an insert 25, 26 mounting. Each insert 25, 26 for mounting is housed in the end section 5, 6 and projecting beyond said section 5, 6. The insert 25, 26 has the shape for example of a ring intended to form a screen internal during welding at the junction between the end 12, 13 of the pipe and the section 5, 6 end. This makes it possible to avoid or limit an internal inerting of the pipe 2, 3 during welding. Due to these inserts 25, 26, the length of the connecting pipe 1 exceeds the length L of the spacing between the two pipes 2, 3 to be connected. To still allow this setting up, and as illustrated in Figures 2 and 3 in particular the connecting pipe 1 may comprise an elastic portion, for example a bellows 14. Thus to arrange the pipe between the ends 12, 13 of pipe, Before welding, the bellows 14 can be compressed (elastically). FIG. 2 illustrates several pairs of ducts 2, 3 each connected by such a connecting duct 1. The connecting pipe 1 thus makes it possible to connect off-center pipes 2, 3 reliably and more easily than previously known solutions. The connection pipe 1, while being simple and inexpensive structure generates little or no additional pressure drop. The use of inserts 25, 26 (also sometimes referred to as "slats") also makes it possible to simplify the welding by forming a shield against the air in the pipe at the welded portions in order to avoid oxidation during welding. As can be seen in FIG. 1, at least one of the pipes 2, 3 may be surrounded by a heat shield 20 itself surrounded by an outer metal sleeve 24, provided with orifices 126 distributed around the end 12 of pipe to be connected. The orifices 126 allow in particular: - the passage of hands of the operators, to achieve for example a possible insulation, - a visual observation, - the establishment of spacer (s) 27. Figure 4 illustrates in particular a body 27 d The spacer 27 is positioned in the sleeve 24. The spacing member 27 is in the form of a disk disposed transversely in the circuit. The spacing member 27 is provided with holes receiving the pipes to guide them and where appropriate to fix them with respect to an outer casing or a heat shield.

FIG. 4 illustrates an additional mounting step in which a first cylindrical thermal half-screen 28 is mounted around the connecting pipes 1. FIG. 5 illustrates an additional mounting step in which a second cylindrical thermal half-screen 17 is mounted around the connecting pipes 1. The two half-screens 17, 28 are for example fixed at their edges and form a cylindrical heat shield around the pipes 1 connecting the pipes 2, 3. Figure 6 illustrates an additional mounting step in which a ferrule (cylindrical tube) 29 is fixed around these screens 17, 18. This outer ring 29 is welded so as to close this connection area. This ring 29 outer closes including access to the pipes 2, 3 provided by the orifices 126 of the sleeve. The ferrule 29 thus forms a tight junction between the two outer casing portions of the two circuits thus connected.

The ferrules and sleeves 24, 29 form an outer envelope within which a vacuum is made. That is, an insulation gap is created between this outer shell and the connected pipes described above.

Claims (15)

REVENDICATIONS1. Fluidic connecting pipe intended to be interposed between the ends (12, 13) spaced apart from two pipes (2, 3), the connecting pipe (1) comprising an oblong body extending in a longitudinal direction (x) defining a direction fluid flow in the pipe (1), the connecting pipe (1) being provided with two end sections (5, 6), characterized in that the pipe (1) for connection comprises a housing (10) disposed between the two end sections (5, 6), the housing (10) extending along a central longitudinal axis (9) parallel to the longitudinal direction (x) of the pipe (1) and fluidly communicating with the two end sections (5, 6), the housing (10) being formed of two separate plates (7, 8) intended to be assembled to one another, the two sections (5, 6) of end being rigidly secured respectively to the two plates (7, 8) and in that the two x end sections (5, 6) are arranged transversely offset with respect to the central longitudinal axis (9) of the housing (1), that is to say that the central longitudinal axes (15, 16) two end portions (5, 6) are each spaced apart by a respective distance (D1, D2) with respect to the central longitudinal axis (9) of the housing (10). 2. Conduit according to claim 1, characterized in that the end sections (5, 6) are straight. 3. Pipe according to claim 1 or 2, characterized in that, in the assembled position of the two plates (7, 8), the longitudinal axes (15, 16) central of the two end sections (5, 6) are parallel. 4. Conduit according to any one of claims 1 to 3, characterized in that, in the assembled position of the two plates (7, 8), the central longitudinal axes (15, 16) of the two sections (5, 6) of end are parallel to the central longitudinal axis (9) of the housing (10). 5. Conduit according to any one of claims 1 to 4, characterized in that the two plates (7, 8) are assembled edge to edge in a plane (11) of joint perpendicular to the axis (9) central longitudinal of housing (10). 6. Conduit according to claim 5, characterized in that the assembly edges of the two plates (7, 8) are symmetrical about the central longitudinal axis (9) of the housing (10) and at multiple angular positions of assembly one plate (7, 8) with respect to the other plate (8, 7) about the central longitudinal axis (9) of the housing (10) and that, depending on the angular position of a plate (7, 8) relative to the other plate (8, 7) around the central longitudinal axis (9) of the housing (10), the transverse distance (in millimeters) between the central longitudinal axes (15, 16) of the two sections (5, 6) is between a minimum spacing and a maximum spacing, the minimum spacing being between zero and (max (D1, D2) - Min (D1, D2)) and the maximum spacing is equal to D1 + D2, with D1 and D2 being the respective transverse spacing distances in mm of the central longitudinal axes (15, 16) of the two sections (5, 6) relative to the central longitudinal axis (9) of the housing (10). 7. Conduit according to any one of claims 1 to 6, characterized in that the two end sections (5, 6) are cylindrical and have equal or different diameters. 8. Conduit according to any one of claims 1 to 7, characterized in that the two plates (7, 8) previously separated are assembled in a relative position determined by welding. 9. Conduit according to any one of claims 1 to 8, characterized in that one of the end sections (5, 6) comprises a portion (14) flexible and elastic between the housing (10) and the end end of said section (5, 6). 10. Installation comprising at least one rigid cryogenic fluid transfer circuit comprising at least one fluid transfer pipe, said at least one inner pipe comprising two distinct straight pipe portions (2, 3), the two pipe portions (2, 3) internally having respective ends (12, 13) spaced apart and facing a longitudinal direction (x), characterized in that the two ends (12, 13) of the pipes (2, 3) are connected to each other. to one another via a connecting pipe (1) according to any one of claims 1 to 9. 11. Installation according to claim 10 characterized in that the circuit is of the double envelope type, that is to say having an outer tubular envelope (24, 29, 30) housing, in its internal volume to be evacuated. the at least one pipe (2, 3). 12. Installation according to claim 10 or 11 characterized in that the two ends (12, 13) pipes (2, 3) connected to each other via a pipe (1) connection are not aligned in the longitudinal direction (x). 13. A method of fluidically connecting two ends (12, 13) of pipes (2, 3) extending along respective longitudinal axes (22, 23) via a pipe (1) connecting between said two ends (12, 13), characterized in that the connecting pipe (1) is according to any one of claims 1 to 9, the method comprising: a step of positioning a first end section (5, 6) of the pipe (1) connecting so as to coincide with a first end (12, 13) of pipe, a step of relative displacement of the two plates (7, 8) in a so-called "concordance" position to also position the second section (6, 5) end of the connecting pipe (1) so as to coincide with the second pipe end (13, 12), a step of locating said position of concordance between the two plates (7, 8) , a step of rigid assembly of the two plates (7, 8) in said matching position, a step of rigid assembly of the two end sections (5, 6) respectively at the two ends (12, 13) of pipes (2, 3). 14. The method of claim 13, characterized in that the step of rigid assembly of the two end sections (5, 6) respectively at the two ends (12, 13) of pipe is made by welding, the ends end sections (5, 6) being each provided with a mounting insert (25, 26) projecting beyond said end section (5, 6), each insert (25, 26) having the shape a ring intended to form an internal screen during welding at the junction between the end (12, 13) of the pipe and the end section (5, 6). 15. Method according to claim 14, characterized in that, in the disassembled and unstressed position, the connecting pipe (1) provided with the inserts (25, 26) has a dimension in the longitudinal direction which is greater than the spacing ( L) between the two ends (12, 13) of pipes (2, 3) to be connected, the connecting pipe (1) comprising a portion (14) elastic and in that the positioning of the connecting pipe (1) for coincide with the two ends (13, 12) of the pipe (1) with the two ends (12, 13) of pipes (2, 3) comprises a longitudinal contraction step of the elastic portion (14) of the pipe ( 1) connection.