TANK WITH INDOOR AND EXTERNAL SPACES AND AT LEAST A CONNECTION SYSTEM WITH FLEXIBLE RADIAL FLATBLES FOR CONNECTING THESE CONTAINERS

Description

[0001] The present application relates to a tank comprising internal and external enclosures and at least one flexible radial blade connecting system linking said enclosures.

[0002] According to an embodiment according to the prior art visible on the figure 1 A hydrogen tank 10 comprises an outer chamber 12, an inner chamber 14 positioned within the outer chamber 12, thermal insulation between the outer and inner chambers 12 and 14, and two diametrically opposed connecting systems 16 and 16' linking the outer and inner chambers 12 and 14. During operation, due to the cryogenic storage temperature of hydrogen, the inner chamber 14 contracts much more than the outer chamber 12. Therefore, at least one of the two connecting systems 16 is configured to allow movement of the inner chamber 14 relative to the outer chamber 12 in a direction of movement. Generally, a first connecting system 16' (the one on the left in the figure 1 ) is rigid and does not allow any relative movement between the external and internal enclosures 12, 14, whereas a second linking system 16 (the one on the right on the figure 1 ) allows relative movement between the external and internal enclosures 12, 14.

[0003] This second linking system 16 includes a female sleeve 18.1 attached to the outer enclosure 12 and a male sleeve 18.2 attached to the inner enclosure 14 and configured to slide in the female sleeve 18.1. These two female and male sleeves 18.1, 18.2 are coaxial and have axes coinciding with the direction of movement.

[0004] This embodiment is not fully satisfactory due to the risk of jamming caused by friction between the female and male sleeves 18.1, 18.2 and the random nature of the contacts between the female and male sleeves 18.1, 18.2.

[0005] Document CA 2 441 775 A1 describes a tank according to the prior art.

[0006] The present invention aims to remedy all or part of the drawbacks of the prior art.

[0007] To this end, the invention relates to a tank comprising an outer enclosure, an inner enclosure positioned within the outer enclosure, and first and second diametrically opposed linking systems connecting the outer and inner enclosures, the outer and inner enclosures moving relative to each other in a direction of movement during operation.

[0008] At least one of the first and second linking systems comprises a central part connected to a first element from the outer enclosure and the inner enclosure and at least three blades distributed around the central part, each blade extending between a first end connected to the central part and a second end which has a head connected to a second element, different from the first element, from the outer enclosure and the inner enclosure, each blade being sufficiently flexible to deform elastically between its first and second ends in the direction of movement.

[0009] According to the invention, the blades are curved and have a profile such that the heads are: offset towards the inner enclosure relative to the central part in the absence of constraints, the absence of constraints corresponding to the absence of hydrogen in the inner enclosure, and arranged substantially in the same transverse plane as the central part in the presence of constraints, in operation, the presence of constraints corresponding to the presence of hydrogen in the cryogenic state in the inner enclosure.

[0010] The blades of the connecting system, thanks to their elastic deformation capabilities, allow the outer and inner chambers to move relative to each other along the direction of travel (particularly due to thermal expansion) while simultaneously absorbing radial forces between them. Furthermore, in the presence of cryogenic hydrogen within the inner chamber, the inner chamber moves away from the outer chamber at the point where the connecting system is located, due to the contraction of the inner chamber caused by its temperature decrease.The fact that the blade profile is curved, and that the blades are positioned approximately in a transverse plane when the inner chamber contracts due to the presence of cryogenic hydrogen, allows the stresses in the blades, in the presence of cryogenic hydrogen in the inner chamber, to be limited to a much lower level than if the blades did not have such a curved profile. Indeed, this curved profile allows the blades to deform without high stresses during the contraction of the inner chamber. It also allows the blades to deform without high stresses when their temperature decreases due to thermal conduction from the inner chamber containing cryogenic hydrogen.

[0011] According to another feature, the central part is connected to the internal speaker, with each head being connected to the external speaker.

[0012] According to another feature, the central part comprises a support integral with the inner enclosure, a ring connected to the outer enclosure via blades and configured to be positioned around the support, and a fastening system configured to immobilize the ring relative to the support, at least in the direction of movement. The connecting system comprises first and second separable parts, the first part comprising the ring, blades, and heads, and the second part comprising the support. According to another feature, the support comprises a base fixed to the inner enclosure by fastening elements and a tubular portion integral with the base, having an axis substantially coinciding with the direction of movement, onto which the ring is fitted.

[0013] According to another feature, the fastening system includes a threaded section provided on the tubular portion and a nut configured to screw onto the threaded section. According to another feature, the fastening system includes a system for locking the nut against rotation and / or a compression ring interposed between the nut and the ring and / or two shear rings positioned on either side of the ring.

[0014] According to another feature, the external enclosure includes an opening at the support and a cover to close the opening.

[0015] According to another feature, the external enclosure includes, for each head, a U-shaped attachment, comprising a base against which the head is fixed, positioned in a substantially transverse plane, and legs connecting the base to the external enclosure.

[0016] According to another characteristic, the linking system includes a safety system comprising a female sleeve attached to the outer enclosure which has an axis coinciding with the direction of movement and a male extension attached to the inner enclosure, positioned in the female sleeve, the male extension and the female sleeve being dimensioned so that there remains a play all around the male extension between the female sleeve and the male extension when the blades are not damaged.

[0017] Other features and advantages will become apparent from the following description of the invention, given by way of example only, with reference to the accompanying drawings, among which: There figure 1 is a schematic representation of a reservoir and a connecting system illustrating an embodiment of the prior art, The figure 2 is a schematic representation of a reservoir and a connecting system illustrating one embodiment of the invention, The figure 3 is a perspective view of part of an external enclosure and a first part of a connecting system at different stages of assembly illustrating one embodiment of the invention, The figure 4 is a perspective view of part of an inner enclosure and a second part of a connecting system illustrating one embodiment of the invention, The figure 5 is a perspective view of the internal and external enclosures visible on the figures 3 And 4 prior to their assembly illustrating one embodiment of the invention, The figure 6 is a perspective view of a portion of a tank after the insertion of the inner enclosure into the outer enclosure, illustrating one embodiment of the invention. figure 7 is a longitudinal section of the first and second parts of the linking system, visible on the figures 3 And 4 Assemblies illustrating one embodiment of the invention, The figure 8 is a longitudinal section of part of a tank illustrating one embodiment of the invention, The figure 9 is a schematic representation of two linking systems having different profiles illustrating two embodiments of the invention, The figure 10 is a schematic representation of several linking systems illustrating several embodiments of the invention, and The figure 11 is a longitudinal section of part of a linking system illustrating another embodiment of the invention.

[0018] According to an embodiment visible on the figure 2 , a tank 20 includes an outer enclosure 22, an inner enclosure 24 positioned in the outer enclosure 22 and first and second connecting systems 26, 26', diametrically opposed, connecting the outer and inner enclosures 22, 24.

[0019] According to one application, the tank 20 is suitable for storing hydrogen in a cryogenic state in the inner enclosure 24. According to this application, the tank 20 includes thermal insulation between the external and internal enclosures 22, 24.

[0020] The external and internal enclosures as well as the thermal insulation are not described further as they may be identical to those of the prior art.

[0021] According to a first configuration, the second 26' connecting system is rigid and identical to the prior art rigid connecting system. According to a second configuration, the first and second 26' connecting systems are identical.

[0022] In operation, at the right of the first linking system 26, the external and internal enclosures 22, 24 can move relative to each other in a direction of movement DD due to the different expansion phenomena of the external and internal enclosures 22, 24.

[0023] For the remainder of this description, a longitudinal direction is parallel to the direction of displacement DD. A radial direction is perpendicular to the direction of displacement DD. A transverse plane is a plane perpendicular to the direction of displacement DD. A longitudinal plane contains the direction of displacement DD.

[0024] The linking system 26 comprises a central part 28 connected to a first element from the outer enclosure 22 and the inner enclosure 24, several blades 30 which extend each between first and second ends, for each blade 30 the first end being connected to the central part 28, the second end having a head 32 connected to a second element, different from the first element, from the outer enclosure 22 and the inner enclosure 24.

[0025] Each blade 30 is radial. By radial blade, we mean that the blade 30 is oriented in an approximately radial direction, its first and second ends being positioned in a longitudinal plane. According to this arrangement, the head 32 is offset relative to the central part 28 in a direction having a component perpendicular to the direction of movement DD.

[0026] Each blade 30 is in the form of a strip of material. It is flexible enough to deform elastically between its first and second ends along the direction of movement DD.

[0027] According to an arrangement, the central part 28 is connected to the inner enclosure 24 and each head 32 is connected to the outer enclosure 22.

[0028] As illustrated on the figure 3 , for each head 32, the external enclosure 22 includes a bracket 34 with a U-shaped section, comprising a base 34.1 against which a head 32 is fixed, positioned in a substantially transverse plane, and legs 34.2 connecting the base 34.1 to the external enclosure 22.

[0029] According to one configuration, each head 32 is connected to a fastener 34 by at least one fastener 36 such as a screw, a bolt, a rivet or others.

[0030] According to one embodiment, the central part 28 comprises a support 38 integral with the inner enclosure 24, a ring 40 connected to the outer enclosure 22 via the blades 30 and configured to be positioned around the support 38, and a fastening system 42 configured to immobilize the ring 40 relative to the support 38 at least in the direction of movement DD. Thus, the connecting system 26 comprises first and second detachable parts 26.1, 26.2.

[0031] According to this embodiment, the first part 26.1, visible on the figure 3 , includes the ring 40, the blades 30, and the heads 32, which form a single piece. The second part 26.2, visible on the figure 4 , includes support 38.

[0032] According to one configuration, the support 38 comprises a base 38.1 fixed to the inner enclosure 24 by fasteners 44, such as bolts or rivets for example, and a tubular portion 38.2 integral with the base 38.1, having an axis A38 substantially coincident with the direction of movement DD and on which the ring 40 is fitted. The base 38.1 and the tubular portion 38.2 form a single piece.

[0033] The support 38 may include a counter plate positioned in the internal enclosure 24 and connected to the base 38.1 by the fixing elements 44.

[0034] The support 38 can be metallic or made of composite material.

[0035] The ring 40 is substantially flat and positioned in operation in a transverse plane. It has an inner diameter substantially equal to or very slightly greater than the outer diameter of the tubular portion 38.2.

[0036] The first part 26.1, comprising the ring 40, the blades 30 and the heads 32, can be metallic or made of composite material.

[0037] As illustrated in part (A) of the figure 9 The first part 26.1, and more specifically the blades 30, are curved. The heads 32 are offset towards the inner chamber 24 relative to the central part 28 in the absence of constraints, and are arranged substantially in the same transverse plane as the central part 28 in the presence of constraints during operation. Thus, when the two outer and inner chambers 22, 24 are at the same temperature, for example, in the absence of hydrogen in the inner chamber 24, the blades 30 have a curved profile. In the presence of hydrogen in the inner chamber 24, the latter deviates from the outer chamber 22 at the linkage system 26. The curved profile of the blades 30 is determined so that the blades 30 are positioned in a transverse plane, as illustrated in part (B) of the figure 9 , when the inner enclosure 24 contracted due to the presence of cryogenic hydrogen in said inner enclosure 24.

[0038] As illustrated on the figures 2 , 3 and part (B) of the figure 10 The connecting system 26 comprises six blades 30 evenly distributed around the periphery of the central part 28. Of course, the invention is not limited to this number of blades 30. Thus, the connecting system 26 may comprise nine blades 30, as illustrated in part (A) of the figure 10 , or three 30 blades, as illustrated in part (C) of the figure 10 Regardless of the embodiment, the linking system 26 comprises at least three blades 30 regularly distributed around the central part 28.

[0039] According to an embodiment visible on the figure 7 The fastening system 42 includes a threaded section 46 provided on the outer cylindrical surface of the tubular portion 38.2 and a nut 48 configured to screw onto the threaded section 46. In addition, the fastening system 42 includes a rotation locking system 50 for the nut 48 cooperating with the latter to immobilize it against rotation and / or a compression ring 52 interposed between the nut 48 and the ring 40.

[0040] According to an embodiment visible on the figures 3 And 7 , the fixing system 42 includes two shear rings 54 positioned on either side of the ring 40, one of them being interposed between the base 38.1 of the support 38 and the ring 40, the other being interposed between the compression ring 52 and the ring 40.

[0041] To allow the installation of the fixing system 42, the external enclosure 22 includes an opening 56 at the support 38 and a cover 58 to close the opening 56. The opening 56 is sized to allow the installation of the fixing system 42 from outside the external enclosure 22.

[0042] A method for mounting tank 20 is illustrated on the figures 3 à 8 .

[0043] After constructing the external and internal enclosures 22, 24, the first part 26.1 is installed by connecting each of the heads 32 to the corresponding bracket 34 using the fastening elements 36, as illustrated in the figure 3 In parallel, the base 38.1 of the support 38 is fixed to the inner enclosure 24 by means of the fixing elements 44, as illustrated in the figure 4 .

[0044] Next, the inner enclosure 24 is positioned within the outer enclosure 22 by positioning the ring 40 of the first part 26.1 around the tubular portion 38.2 of the support 38, as illustrated in the figures 5 And 6 . In order to be able to place the inner enclosure 24 in the outer enclosure 22, the latter is made in two parts which are assembled after the inner enclosure 24 has been placed.

[0045] The components of the fastening system 42 are introduced through the opening 56 and put in place to immobilize the ring 40 relative to the support 38 according to the direction of movement DD.

[0046] Finally, the opening 56 is closed by fixing the cover 58 onto the external enclosure 22 all around the opening 56 by any suitable means, such as by welding for example.

[0047] The blades 30 of the connecting system 26 allow the external and internal enclosures 22, 24 to move relative to each other along the direction of movement DD due to expansion phenomena. In addition, the blades 30 absorb radial forces (oriented perpendicular to the direction of movement DD) between the external and internal enclosures 22, 24.

[0048] According to an embodiment visible on the figure 11The linking system 26 includes a safety system 60 enabling the outer enclosure 22 to support the inner enclosure 24 in the event of breakage of the blades 30. This linking system 26 includes a female sleeve 60.1 integral with the outer enclosure 22, more particularly with its cover 58, having an axis A60.1 coinciding with the direction of movement DD and a male extension 60.2, integral with the inner enclosure 24, configured to be positioned in the female sleeve 60.1. The female sleeve 60.1 and the male extension 60.2 are dimensioned so that, in the absence of contraction of the inner chamber 24, the male extension 60.2 does not interfere with the cover 58, and so that, in the presence of contraction of the inner chamber 24, a part of the male extension 60.2 is always positioned in the female sleeve 60.1. The female sleeve 60.1 and the male extension 60.2 are also dimensioned so that there remains a play all around the male extension 60.2 between the latter and the female sleeve 60.1, when the blades 30 are not damaged, so that the safety system 60 does not induce any friction between the female sleeve 60.1 and the male extension 60.2.

[0049] According to one configuration, the male extension 60.2 can be an extension of the support 38, more particularly of its tubular portion 38.2. According to another configuration, the male extension 60.2 is a tube separate from the support 38 fitted into the tubular portion 38.2 of the support 38.

Claims

1. Tank comprising an outer chamber (22), an inner chamber (24) positioned in the outer chamber (22) and first and second link systems (26, 26'), diametrically opposite, linking the outer and inner chambers (22, 24), the outer and inner chambers (22, 24) being displaced with respect to one another in a direction of displacement (DD) in operation, the tank being such that at least one of the first and second link systems (26, 26') comprises a central part (28) linked to a first element out of the outer chamber (22) and the inner chamber (24) and at least three blades (30) distributed around the central part (28), each blade (30) extending between a first end linked to the central part (28) and a second end which has a head (32) linked to a second element, different from the first element, out of the outer chamber (22) and the inner chamber (24), each blade (30) being sufficiently flexible to be deformed elastically between its first and second ends in the direction of displacement (DD), characterized in that the blades (30) are curved and have a profile such that the heads (32) are: - offset towards the inner chamber (24) with respect to the central part (28) in the absence of strains, the absence of strains corresponding to the absence of hydrogen in the inner chamber (24), and - disposed substantially in a same transverse plane as the central part (28) in the presence of strains, in operation, the presence of strains corresponding to the presence of hydrogen in the cryogenic state in the inner chamber (24).

2. Tank according to Claim 1, characterized in that the central part (28) is linked to the inner chamber (24) and in that each head (32) is linked to the outer chamber (22).

3. Tank according to the preceding claim, characterized in that the central part (28) comprises a support (38) secured to the inner chamber (24), a ring (40) linked to the outer chamber (22) via the blades (30) and configured to be positioned around the support (38) and a fixing system (42) configured to immobilize the ring (40) with respect to the support (38) at least in the direction of displacement (DD), the link system (26) comprising dissociable first and second parts (26.1, 26.2), the first part (26.1) comprising the ring (40), the blades (30) and the heads (32), the second part (26.2) comprising the support (38).

4. Tank according to the preceding claim, characterized in that the support (38) comprises a base (38.1) fixed onto the inner chamber (24) by the fixing elements (44) and a tubular portion (38.2) secured to the base (38.1), having an axis (A38) substantially coinciding with the direction of displacement (DD) and onto which the ring (40) is fitted.

5. Tank according to one of Claims 3 and 4, characterized in that the fixing system (42) comprises a threaded section (46) provided on the tubular portion (38.2) and a nut (48) configured to be screwed onto the threaded section (46).

6. Tank according to the preceding claim, characterized in that the fixing system (42) comprises a system (50) for blocking rotation of the nut (48) and / or a compression fitting (52) inserted between the nut (48) and the ring (40) and / or two shear rings (54) positioned on either side of the ring (40).

7. Tank according to one of Claims 3 to 6, characterized in that the outer chamber (22) comprises an aperture (56) in line with the support (38) and a cover (58) for blocking the aperture (56).

8. Tank according to one of Claims 2 to 7, characterized in that the outer chamber (22) comprises, for each head (32), an attachment (34) with a U section, comprising a base (34.1) against which the head (32) is fixed, positioned in a substantially transverse plane and legs (34.2) linking the base (34.1) to the outer chamber (22).

9. Tank according to one of the preceding claims, characterized in that the link system (26) comprises a safety system (60) comprising a female sleeve (60.1) secured to the outer chamber (22), which has an axis (A60.1) coinciding with the direction of displacement (DD) and a male extension (60.2), secured to the inner chamber (24), positioned in the female sleeve (60.1), the male extension (60.2) and the female sleeve (60.1) being dimensioned such that there remains a play all around the male extension (60.2) between the female sleeve (60.1) and the male extension (60.2) when the blades (30) are not damaged.