Tank, In Particular For A Liquid Hydrogen Reservoir, Provided With At Least One Dome Fixed By Way Of An Outer Welded Joint

Abstract

A tank, in particular for a liquid hydrogen reservoir, provided with at least one dome fixed by way of an outer welded joint and having a central portion provided with at least one free end including a first connecting element and at least one dome provided with an open end including a second connecting element, the dome and the central portion being able to be joined together, the first connecting element and the second connecting element being configured to form, when the central portion and the dome are joined together, a protruding tab extending toward the outside of the tank and able to be welded to a protruding end, such a protruding tab making it possible in particular to join together the tank, this being done entirely from the outside of said tank, and to easily mount and dismount the dome, in particular without accessibility issues.

1 . A tank for a liquid hydrogen reservoir, said tank comprising:
 at least one central portion having at least one end referred to as free end and at least one dome having an end referred to as open end, said dome and said central portion joined together by arranging the open end of said dome on the free end of the central portion, the free end of the central portion comprising a first connecting element, the open end of the dome comprising, on an outer face of the dome, a second connecting element, and said first connecting element and said second connecting element configured to form, when the central portion and the dome are joined together, a protruding tab extending toward the outside of the tank and welded at a protruding end by a weld bead,   wherein the protruding tab has a total length (L) which is greater than or equal to twice a depth (P) of the weld bead.   
     
     
         2 . The tank as claimed in  claim 1 ,
 wherein the total length (L) of the protruding tab is less than or equal to ten times the depth (P) of a weld bead forming the weld joint of said protruding tab.   
     
     
         3 . The tank as claimed in  claim 1 ,
 wherein the first connecting element corresponds to an extension of the central portion, at the free end, wherein the second connecting element corresponds to a longitudinal flange arranged on an outer face of the dome, and wherein said extension and said longitudinal flange have cooperating shapes such that the longitudinal flange can be inserted with peripheral contact into the extension so as to form said protruding tab.   
     
     
         4 . The tank as claimed in  claim 1 ,
 wherein the first connecting element corresponds to a first flange arranged on an outer face of the central portion, wherein the second connecting element corresponds to a second flange arranged on an outer face of the dome, and wherein said first flange and said second flange have cooperating shapes such that a face of the first flange is able to bear against a face of the second flange so as to form said protruding tab.   
     
     
         5 . The tank as claimed in  claim 4 ,
 wherein the protruding tab, formed by the first flange and the second flange, has a bent shape.   
     
     
         6 . The tank as claimed in  claim 1 ,
 wherein at least one of said first and second connecting elements is a fitted piece.   
     
     
         7 . The tank as claimed in  claim 1 ,
 wherein, on an inner face the central portion comprises a shoulder, and wherein a lateral face of the open end of the dome is configured to bear against the shoulder when the central portion and the dome are joined together.   
     
     
         8 . The tank as claimed in  claim 1 ,
 wherein the at least one dome comprises first and second domes, wherein the free end of the central portion comprises first and second free ends, and wherein one of said first and second domes is fixed on one of said first and second free ends and the other of said first and second domes is fixed on the other of said first and second free ends.   
     
     
         9 . A reservoir for liquid hydrogen, comprising:
 at least one tank as claimed in  claim 1 .   
     
     
         10 . The reservoir as claimed in  claim 9 ,
 the at least one tank comprises first and second tanks as claimed in  claim 1 , wherein a first one of said first and second tanks is a tank referred to as outer tank and the second one of said first and second tanks is a tank referred to as inner tank, and wherein the inner tank is arranged inside the outer tank.   
     
     
         11 . A method for manufacturing a tank as claimed in  claim 1 ,
 wherein the method comprising:
 a joining step (E 1 ), including positioning an open end of a dome, provided with a first connecting element, on a free end of a central portion, provided with a second connecting element, such that said first and second connecting elements form a protruding tab, provided with a protruding end configured to be welded by way of a weld bead, said protruding tab having a total length (L) which is greater than or equal to twice a depth (P) of said weld bead, and keeping said dome and said central portion thus positioned in position in order to carry out a welding operation; and 
 a welding step (E 2 ), including welding said first and second connecting elements to one another at the protruding end by forming the weld bead. 
   
     
     
         12 . A method for maintaining a tank as claimed in  claim 1 ,
 wherein the method comprising:
 a cutting-out step (E 3 ), including cutting out a part of a protruding tab having an initial length (L 1 ), said cut-out part corresponding at least to a welded protruding end of said protruding tab having a weld bead, and said cut-out part having a length which is greater than a depth (P) of said weld bead; and 
 a removing step (E 4 ), including opening the tank having at least one dome and a central portion by separating at least said dome from said central portion, which are no longer fixed to one another, allowing access to the tank in order to carry out maintenance operations. 
   
     
     
         13 . The method as claimed in  claim 12 , further comprising:
 a remounting step (E 5 ) including repositioning the dome on the central portion so as to reform the protruding tab, said protruding tab having a reduced length (L 2 ) corresponding to its initial length (L 1 ) minus the length of said cut-out part, and welding the dome and the central portion to one another at the protruding end of said protruding tab by forming a weld bead having a depth (P) which is less than the reduced length (L 2 ) of the protruding tab.