Tank pan with a jacket and at least one front wall, joined in a way to limit front wall deformation

Description

[0001] The present application relates to a tank vessel comprising a shell and at least one end wall assembled in such a way as to limit deformations of said end wall in operation and to a cryogenic tank comprising at least one such vessel.

[0002] US document 2023 / 036707 A1 discloses a tank, in particular for a liquid hydrogen reservoir, said tank comprising at least one central section having at least one so-called free end and at least one dome having an so-called open end, said dome and said central section being capable of being assembled, the free end of the central section comprising a first connecting element, the open end of the dome comprising, on an external face of the dome, a second connecting element, said first connecting element and said second connecting element being configured to form, when the central section and the dome are assembled, a protruding tab extending outwards from the tank and capable of being welded to a protruding end.

[0003] According to an embodiment visible on the figure 1 An aircraft 10 comprises several cryogenic tanks 12 configured to store hydrogen in a cryogenic state, several hydrogen-powered engines 14, and a fuel system 16 configured to deliver hydrogen from the tanks 12 to the engines 14. Each cryogenic tank 12 comprises an inner tank, an outer tank in which the inner tank is positioned, and two diametrically opposed connecting systems linking the inner and outer tanks.

[0004] According to an embodiment visible on the figures 2 et 3 Each tank 18 comprises a ferrule 20 extending between first and second ends 20.1, 20.2, and first and second end walls 22, 24 positioned respectively at the first and second ends 20.1, 20.2 of the ferrule 20 to close it. The ferrule 20 is cylindrical and has an axis of revolution A20.

[0005] For the remainder of this description, a longitudinal direction is parallel to the axis of revolution A20. A longitudinal plane is a plane containing the axis of revolution A20. A transverse plane is perpendicular to the axis of revolution A20. A radial direction is perpendicular to the axis of revolution A20.

[0006] Each of the first and second ends 20.1, 20.2 of the ferrule 20 is circular and positioned in a transverse plane. Each end wall 22, 24 has a domed shape and includes a free edge 22.1, 24.1 positioned in a plane and connected to the ferrule 20 by at least one weld line 26 qui extends over the entire circumference of the ferrule 20.

[0007] According to an initial configuration visible on the figures 2 et 3 , for each end wall 22, 24, the free edge 22.1, 24.1 and the first or second end 20.1, 20.2 of the ferrule 20 are positioned end to end and connected by the weld line 26.

[0008] According to a second configuration visible on the figure 4 , at least one of the end walls 22, 24 comprises: a central part 28 in the shape of a dome which has a free edge 28.1 positioned in a first plane P1, the center of the central part 28 being offset in a first direction with respect to the first plane P1, a peripheral sleeve 30, positioned around the central part 28, which extends between first and second ends 30.1, 30.2, the second end 30.2 being offset in the first direction with respect to the first end 30.1, a junction zone 32 connecting the free edge 28.1 of the central part 28 and the first end 30.1 of the peripheral sleeve 30.

[0009] Thus, the central part 28 and the peripheral sleeve 30 form a single piece which has an edge C1 positioned in the first plane P1.

[0010] In addition, the ferrule 20 has a counterbore 34 which has an inner lateral surface 34.1 and a bottom 34.2 distant from the first end 20.1 of the ferrule 20. The inner lateral surface 34.1 has a diameter substantially equal to the diameter of the outer lateral surface F30 of the peripheral sleeve 30. The counterbore 34 has a depth P (distance separating the bottom 34.2 of the counterbore 34 and the first end 20.1 of the ferrule 20) substantially equal to the distance separating the first and second ends 30.1, 30.2 of the peripheral sleeve 30.

[0011] According to this second configuration, the end wall 22, 24 is positioned in the counterbore 34, the edge C1 of the end wall 22, 24 being pressed against the bottom 34.2 of the counterbore 34, the second end 30.2 of the peripheral sleeve 30 being positioned substantially in the same plane as the first end 20.1 of the ferrule 20. The end wall 22, 24 and the ferrule 20 are connected by a weld 36, positioned between the ferrule 20 and the peripheral sleeve 30, which extends over the entire circumference of the ferrule from the second end 30.2 of the peripheral sleeve 30 and / or the first end 20.1 of the ferrule 20.

[0012] Weld 36 has a length L (dimension taken parallel to the longitudinal direction) less than half the depth P of the counterbore 34.

[0013] Compared to the first configuration, this second solution simplifies the assembly of the tank 18 and any dismantling of the end walls 22, 24.

[0014] As illustrated on the figure 4 Due to the very high pressure of the fluid stored in the tank 18, the junction zone 32 tends to deform in the radial direction and to move away from the inner lateral surface 34.1 of the counterbore 34. Thus, in operation, the weld 36 is subjected to shear stresses but also to bending and tensile stresses due to the deformation of the junction zone 32. To avoid this deformation, the length L of the weld 36 is increased and / or the thickness (dimension taken in a transverse plane) of the peripheral sleeve 30 is increased.

[0015] These solutions are not satisfactory because they lead to an increase in the mass of the tank, to more complex assembly, or even to making it impossible to dismantle and reassemble the end walls.

[0016] The present invention aims to remedy all or part of the drawbacks of the prior art.

[0017] To this end, the invention relates to a tank comprising a shell extending between first and second ends and at least one end wall positioned at the first end; the end wall comprising a central dome-shaped part, a peripheral sleeve positioned around the central part and a junction zone connecting the central part and the peripheral sleeve and having a first edge;the ferrule having an axis of revolution and comprising at least first and second sections, the first section extending between the first end of the ferrule and the second section, the first and second sections having respectively first and second internal lateral surfaces, the second internal lateral surface having a diameter smaller than that of the first internal lateral surface, the ferrule having a second edge connecting the first and second internal lateral surfaces; the tank comprising a weld connecting the first section of the ferrule and the peripheral sleeve of the end wall.

[0018] According to the invention, the first and second edges of the end wall and the ferrule have shapes configured to immobilize the junction area with respect to the ferrule in a radial direction perpendicular to the axis of revolution.

[0019] Since the end wall junction area no longer deviates from the first section of the shell during operation due to the pressure of the fluid stored in the tank, the weld is no longer subjected to bending and tensile stresses. Consequently, it is not necessary to stiffen the peripheral sleeve and / or reinforce the weld to withstand such stresses. According to another feature, at least one element between the first edge of the end wall and the second edge of the shell includes or has at least one protruding shape. Additionally, at least one second element, different from the first element, between the first edge of the end wall and the second edge of the shell includes, for each protruding shape, or partially delimits at least one housing configured to accommodate the protruding shape in order to immobilize the junction area relative to the shell in the radial direction.

[0020] According to another characteristic, the second edge of the ferrule and the first edge of the end wall are positioned in transverse planes perpendicular to the axis of revolution.

[0021] According to another feature, the end wall includes a projecting rib extending around the circumference of the first edge. Additionally, the ferrule has a groove extending around the circumference of the second edge, designed to accommodate the rib. According to another feature, the groove and rib have complementary cross-sections.

[0022] According to another characteristic, the rib is located in the extension of the outer lateral surface of the peripheral sleeve.

[0023] According to another characteristic, the first and second sections are connected by a second truncated conical edge which flares out as it moves away from the first end of the ferrule, the first edge of the end wall being truncated conical and having a conicity substantially identical to that of the second edge of the ferrule.

[0024] The invention also relates to a cryogenic reservoir comprising a tank according to one of the preceding characteristics.

[0025] 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 perspective view from an aircraft, The figure 2 is a perspective view of a tank being assembled, illustrating an earlier art assembly method. figure 3 is a perspective view of the tank visible on the figure 2 at the end of assembly, The figure 4 is a longitudinal section of part of a vat illustrating a method of execution from the earlier art, The figure 5 is a longitudinal section of part of a tank illustrating one embodiment of the invention, The figure 6 is a longitudinal section of part of a tank illustrating another embodiment of the invention.

[0026] According to embodiments visible on the figures 5 et 6 , a tank 40 includes a shell 42 which extends between first and second ends 42.1, at least one first end wall 44 positioned at the level of the first end 42.1 of the shell 42 to close it and at least one first assembly 46 connecting the first end wall 44 and the first end 42.1 of the shell 42.

[0027] For the sake of simplicity, only the first end 42.1 of the ferrule is shown on the figures 5 et 6 Similarly, only part of the first assembly 46 connecting the first end wall 44 and the ferrule 42 is visible on the figures 5 et 6 .

[0028] The tank 40 includes a second end wall connected to the second end of the shell 42 by a second assembly. In one configuration, the second end wall and the second assembly are identical to the first end wall 44 and the first assembly 46, respectively. Alternatively, the second end wall could be different from the first end wall 44 and / or the second assembly could be different from the first assembly 46.

[0029] According to one application, tank 40 is configured to store a fluid such as hydrogen in a cryogenic state at high pressure. According to one arrangement, a cryogenic tank intended for storing a fluid in a cryogenic state, such as hydrogen, and for being positioned in a vehicle, such as an aircraft, comprises at least one tank. According to one embodiment, the cryogenic tank comprises an inner tank and an outer tank in which the inner tank is positioned, at least one of the inner and outer tanks conforming to tank 40, a portion of which is visible on the figures 5 et 6 .

[0030] Depending on the configuration, the ferrule 42 is cylindrical or slightly frustoconical and has an axis of revolution. Each of the first and second ends 42.1 of the ferrule 42 is circular and positioned in a transverse plane.

[0031] According to the embodiments visible on the figures 5 et 6 The end wall 44 comprises: a central part 48 in the shape of a dome which has a free edge 48.1 positioned in a first plane P1, the central part 48 having a center offset in a first direction relative to the first plane P1, a peripheral sleeve 50, positioned around the central part 48, which extends between first and second ends 50.1, 50.2, the second end 50.2 being offset in the first direction relative to the first end 50.1, a junction zone 52 connecting the free edge 48.1 of the central part 48 and the first end 50.1 of the peripheral sleeve 50.

[0032] Thus, the central part 48 and the peripheral sleeve 50 form a single piece. The junction zone 52 has a first edge C1.

[0033] The central part 48 has an inner surface F48 oriented towards the inside of the tank 40. The peripheral sleeve 50 has an outer lateral surface F50 opposite to the central part 48 and oriented towards the ferrule 42.

[0034] The ferrule 42 comprises at least first and second sections 54, 56 coaxial with each other and with the axis of revolution of the ferrule 42, the first section 54 being cylindrical and extending between the first end 42.1 of the ferrule 42 and the second section 56. The first section 54 comprises a first inner lateral surface 54.1. The second section 56 comprises a second inner lateral surface 56.1 having a diameter smaller than that of the first inner lateral surface 54.1. The first section 54 is configured to house the peripheral sleeve 50 of the end wall 44.

[0035] According to an initial configuration visible on the figure 5 The first and second inner lateral surfaces 54.1, 56.1 of the first and second sections 54, 56 are connected by a second annular edge C2 positioned in a transverse plane (perpendicular to the axis of revolution of the ferrule 42). According to this first configuration, the first inner lateral surface 54.1 and the second edge C2 form a counterbore.

[0036] According to a second configuration visible on the figure 6 , the first and second inner lateral surfaces 54.1, 56.1 of the first and second sections 54, 56 are connected by a second truncated conical edge C2' which flares out as it moves away from the first end 42.1 of the ferrule 42.

[0037] The first inner lateral surface 54.1 of the first section 54 has a diameter D54.1 and a longitudinal dimension L54.1 corresponding to a dimension taken parallel to the longitudinal direction between the first end 42.1 of the ferrule 42 and the second edge C2, C2'. The diameter D54.1 of the first inner lateral surface 54.1 of the first section 54 is substantially equal to, or very slightly greater than, the diameter of the outer lateral surface F50 of the peripheral sleeve 50. According to one arrangement, the longitudinal dimension L54.1 of the first inner lateral surface 54.1 of the first section 54 is determined such that when the end wall 44 is positioned in the first section 54 and against the second edge C2, C2' of the ferrule 42, the second end 50.2 of the peripheral sleeve 50 is positioned approximately in the same transverse plane as the first end 42.1 of the ferrule 42.

[0038] The tank (more specifically the assembly 46) includes a weld 58 positioned between the shell 42 and the end wall 44, more specifically between the first section 54 of the shell 42 and the peripheral sleeve 50 of the end wall 44, extending from the second end 50.2 of the peripheral sleeve 50 of the end wall 44 and / or the first end 42.1 of the shell 42. This weld 58 has a length L corresponding to a dimension taken parallel to the longitudinal direction. Depending on the configuration, the length L is less than half the longitudinal dimension L54.1 of the first inner lateral surface 54.1 of the first section 54. This weld 58 extends continuously around the entire circumference of the shell 42. It can be produced by any suitable welding process, such as a friction welding process.According to one feature of the invention, the first and second edges C1, C2, C2' of the end wall 44 and the ferrule 42 have shapes configured to immobilize the junction zone 52 relative to the ferrule 42 in a radial direction. Since the junction zone 52 of the end wall 44 does not deviate from the first section 54 of the ferrule 42, more particularly from its first inner lateral surface 54.1, during operation due to the pressure of the fluid stored in the tank 40, the weld 58 is no longer subjected to bending and tensile stresses. Consequently, it is not necessary to stiffen the peripheral sleeve 50 and / or reinforce the weld 58 to withstand such stresses.

[0039] According to the second configuration visible on the figure 6 , the first edge C1 of the end wall 44 has a projecting shape 60 and the second edge C2' of the ferrule 42 partially delimits a housing 62 configured to house the projecting shape 60 in order to immobilize the junction area 52 with respect to the ferrule 42 in the radial direction. According to one arrangement, the first edge C1 of the end wall 44 is frustoconical and has a taper substantially identical to that of the second edge C2' of the ferrule 42. In addition, the ferrule 42 has a frontal groove, delimited by the first inner lateral surface 54.1 of the first section 54 and the second edge C2', which extends over the entire circumference of the ferrule 42 and accommodates at least a projecting portion of the junction zone 52 of the end wall 44. According to one arrangement, the first edge C1 extends without discontinuity from the inner surface F48 of the central portion 48 of the end wall 44. According to the first configuration visible on the figure 5 The first and second edges C1, C2 of the end wall 44 and the ferrule 42 are positioned in transverse planes. According to the first configuration, at least one element among the first edge C1 of the end wall 44 and the second edge C2 of the ferrule 42 includes at least one projecting shape 60. In addition, at least one second element, different from the first element, among the first edge C1 of the end wall 44 and the second edge C2 of the ferrule 42 includes, for each projecting shape 60, at least one housing 62 configured to house the projecting shape 60 in order to immobilize the junction area 52 with respect to the ferrule 42 in the radial direction.

[0040] According to an arrangement, the end wall 44 comprises several projecting shapes 60 relative to the first edge C1, disjointed and distributed over the circumference of the first edge C1. In addition, the ferrule 42 comprises, at the level of the second edge C2, a housing 62 for each projecting shape 60.

[0041] According to another arrangement visible on the figure 5The end wall 44 comprises a single protruding 60 relative to the first edge C1, in the form of a rib extending around the entire circumference of the first edge C1. In addition, the ferrule 42 has a single recess 62 in the form of a groove extending around the entire circumference of the second edge C2, configured to house the rib. This groove and rib have complementary cross-sections, such as U-shaped. Of course, the invention is not limited to this geometry for the cross-sections of the rib and the groove. In one configuration, the rib is located in line with the outer lateral surface F50 of the peripheral sleeve 50. In addition, the groove-shaped recess 62 is located in line with the first inner lateral surface 54.1 of the first section 54.

Claims

1. Tank comprising a shell (42) that extends between first and second ends (42.1) and at least one end wall (44) positioned at the first end (42.1); the end wall (44) having a central part (48) in the shape of a dome, a peripheral sleeve (50) positioned around the central part (48) and a junction zone (52) connecting the central part (48) and the peripheral sleeve (50) and having a first edge face (C1); the shell (42) having an axis of revolution and having at least first and second portions (54, 56), the first portion (54) extending between the first end (42.1) of the shell (42) and the second portion (56), the first and second portions (54, 56) respectively having first and second inner lateral surfaces (54.1, 56.1), the second inner lateral surface (56.1) having a diameter smaller than that of the first inner lateral surface (54.1), the shell (42) having a second edge face (C2, C2') connecting the first and second inner lateral surfaces (54.1, 56.1); the tank having a weld (58) connecting the first portion (54) of the shell (42) and the peripheral sleeve (50) of the end wall (44); wherein the first and second edge faces (C1, C2, C2') of the end wall (44) and of the shell (42) have shapes configured to immobilize the junction zone (52) with respect to the shell (42) in a radial direction perpendicular to the axis of revolution.

2. Tank as claimed in the preceding claim, wherein at least one element among the first edge face (C1) of the end wall (44) and the second edge face (C2) of the shell (42) comprises or has at least one projecting shape (60) and wherein at least one second element, different from the first element, among the first edge face (C1) of the end wall (44) and the second edge face (C2) of the shell (42) comprises, for each projecting shape (60), or partially delimits at least one housing (62) configured to house the projecting shape (60) in order to immobilize the junction zone (52) with respect to the shell (42) in the radial direction.

3. Tank as claimed in the preceding claim, wherein the second edge face (C2) of the shell (42) and the first edge face (C1) of the end wall (44) are positioned in transverse planes perpendicular to the axis of revolution.

4. Tank as claimed in either of claims 2 and 3, wherein the end wall (44) comprises a shape (60), projecting with respect to the first edge face (C1), in the form of a rib that extends over the entire circumference of the first edge face (C1) and wherein the shell (42) has a housing (62) in the form of a groove, which extends over the entire circumference of the second edge face (C2), configured to house the rib.

5. Tank as claimed in the preceding claim, wherein the groove and the rib have complementary sections.

6. Tank as claimed in either of claims 4 and 5, wherein the peripheral sleeve (50) has an outer lateral surface (F50) oriented toward the first portion (54) and wherein the rib is situated in the continuation of the outer lateral surface (F50) of the peripheral sleeve (50).

7. Tank as claimed in claim 1 or 2, wherein the first and second portions (54, 56) are connected by a second, frustoconical edge face (C2') that flares away from the first end (42.1) of the shell (42) and wherein the first edge face (C1) of the end wall (44) is frustoconical and has a conicity substantially identical to that of the second edge face (C2') of the shell (42).

8. Cryogenic reservoir comprising at least one tank as claimed in one of the preceding claims.