FR2841880A1 - Reinforced cellular metal panel comprises two parallel sheets, linked by waveform section panel, welded along peaks to outer panels - Google Patents

Abstract

The metal panel comprises two parallel walls (2,3) separated by a waveform panel, with the peaks of the waves being fixed to respective panels. The peaks of the waves are flat, as are the sections which link a wave peak to a wave trough. This produces a strong structure for use in manufacture of transformer casings. The reinforced metal panel comprises two external walls (2,3) which lie parallel to each other. These are spaced apart by an intermediate wall (4) which has a waveform cross-section, with the peaks of the waves being fixed to respective panels where they make contact. The peaks of the waves are flat, as are the sections which link a wave peak to a wave trough, thus defining trapezoidal channels between the intermediate wall and the external walls. The small bases of the trapezium sections form an angle of between 25 and 75 degrees with the walls. The waveform has a wavelength (lambda ) which lies between 1.6d and 3.4d, where d is the separation between the internal faces of the panels.

Description

The present invention relates to the technical field of panels

  cellular or reinforced metal, used in mechanical engineering or boilermaking for the production of structures that must withstand significant efforts or constraints. In a preferred but not exclusive application, the invention relates to the field of reinforced panels used for the manufacture of submerged electrical transformer tanks. In the above field, it is known to implement, for the manufacture of a transformer tank, metal plates which are reinforced at their outer face by means of frames consisting of profiles, in "U" folded or UPN or "I" beam, such as IPN, welded to the metal wall to be reinforced. Such a method of manufacture gives full satisfaction with regard to the mechanical characteristics of the tank thus produced but has, however, the disadvantage of involving relatively high labor costs.

  1 5 for the establishment of reinforcing profiles.

  Moreover, insofar as such tanks are generally made of steel, the application of an anti-corrosion coating on the tank, particularly at the reinforcement ribs, can be difficult and requires a hand time.

  also relatively important.

  It therefore appears to be necessary to have structural elements that make it possible to simplify, substantially, the manufacture of such a transformer tank, in particular by reducing manufacturing and anti-corrosion treatment times, while offering mechanical strength characteristics similar to those of those offered by

  the tanks manufactured according to the prior art.

  In order to achieve this objective, the invention relates to a reinforced metal panel, for the manufacture of metal tanks in particular, characterized in that it comprises at least two outer walls substantially parallel to each other and braced by a corrugated intermediate wall and fixed, at the level of some at

  less peaks of its waves, corresponding external walls.

  According to the invention, the various constituent walls of the metal panel may be made of any suitable metallic material, such as, for example, steel, stainless steel or even special steels such as corten or else 'aluminum. Of course, it is not necessary, according to the invention, that the various constituent walls of the reinforced metal panel all have an identical thickness. The implementation of a corrugated intermediate wall, which struts the two outer walls, provides a metal panel which has mechanical strength characteristics equivalent to those of a solid sheet

  reinforced which would have a thickness between 6 and 30mm.

  According to the invention, the waves of the intermediate wall may have different shapes such as, for example, a substantially sinusoidal shape, a crenellated or rectangular waveform or, still, a waveform

1 0 triangular.

  According to a preferred embodiment but not exclusive of the invention, the peaks of the waves of the intermediate wall are flat, so as to provide a

  stable bearing surface on the corresponding outer wall.

  In a preferred but not strictly necessary manner, the corrugations of the intermediate wall are then chosen so as to present, in cross-section

  transverse, a substantially trapezoidal shape.

  According to one characteristic of the invention, the trapezes defined by the waves are isosceles and the sides of the trapezium form, with the small base of the trapezium, resting on

  an outer wall, an angle of between 250 and 75.

  According to another characteristic of the invention, the corrugations, whatever their shape, have a pitch X that substantially respects the relation: 1.6d <X <3.4d od is equal to the distance between the inner faces of the two outer walls . This advantageous characteristic of the invention makes it possible to obtain a good compromise between

  the weight of the reinforced metal panel, its thickness and mechanical strength.

  According to one embodiment of the metal panel according to the invention, at least one of the outer walls has at least one folded edge and welded to the opposite end of the other outer wall. have a metal panel providing, at one of its ends to

  less, a solid edge easy to solder.

  In the same sense, according to another feature of the invention, preferred but not strictly necessary, the two outer walls each have, on the one hand, a straight edge and, on the other hand, opposite the right edge, a folded and welded edge at

  right edge opposite the other outer wall.

  According to a preferred but not strictly necessary characteristic of

  the invention, the outer walls are substantially flat.

  However, the outer walls could also be curved, while

  remaining parallel to each other.

  The invention also relates to a tank for an immersed electric transformer, of the type comprising a bottom and at least one side wall characterized in that the side wall or the bottom comprises at least one reinforced panel according to

the invention.

  Preferably, the tank has a rectangular cross section and the side walls of the tank are each formed by a panel

  reinforced metal according to the invention.

  The reinforced metal panel according to the invention can be manufactured, either individually or in series, using techniques known in mechanical engineering. In this respect, it should be emphasized that reinforced metal

  according to the invention is particularly suitable for mass production.

  Thus, the invention also relates to a method of manufacturing a panel

  reinforced metal according to the invention.

  This manufacturing process consists, in particular, in successively: * cutting three sheet blanks to the dimension of the developed two outer walls, on the one hand, and the inner wall, on the other hand, * distribute the three blanks on three separate shaping stations, * proceed, on each station, to the formatting of the corresponding blank, * assemble the intermediate wall shaped with an outer wall to obtain a primary assembly, * assemble the other outer wall with the primary set to get the

reinforced metal panel.

  The invention also relates to an installation for implementing such a manufacturing method. The installation then comprises: at least one sheet blank cutting unit with the dimensions of the developed external walls and the intermediate wall, a first manufacturing station of a first external wall comprising means for taking care of a sheet metal blank cut to the dimensions of the developed first outer wall and means for shaping the sheet blank, * a second manufacturing station of the second outer wall comprising means for taking care of a blank sheet metal cut to the dimensions of the developed second outer wall and means for shaping the sheet blank, * a third manufacturing station of the inner wall comprising means for handling a sheet blank cut to dimensions of the development of the intermediate wall and the means for shaping the sheet blank, * a primary assembly station comprising means for supporting on the one hand the first outer wall from the first manufacturing station and secondly from the intermediate wall from the third manufacturing station and from the means for assembling the first external wall with the intermediate wall, a secondary assembly station comprising means for supporting on the one hand, the primary assembly consisting of the first outer wall and the intermediate wall and, on the other hand, the second outer wall and means for assembling the second inner wall to the

  less with the intermediate wall of the primary assembly.

  According to the invention these different workstations could be merged

  to reduce the number to three positions for example.

  Various other features of the invention will emerge from the description below, made with reference to the accompanying drawings which illustrate a preferred form,

  but not limited to the production of a reinforced metal panel according to the invention, as well as a submerged electric transformer tank and an installation for automated or semi-automated panel manufacture

reinforced according to the invention.

  Fig. 1 is a perspective view of a preferred embodiment of a reinforced panel according to the invention, carried transversely to the direction of extension of the

reinforcing waves.

  Fig. 2 is a section on plane II-II of FIG. 1.

  Fig. 3 is a schematic perspective of an installation for manufacturing

  in series of the panel, as shown in fig. 1.

  Fig. 4 is a transverse cross-section of an immersed electric transformer tank comprising reinforced metal panels, as illustrated

in fig. 1.

  Fig. 5 is a partial perspective of the tank, as illustrated in FIG. 3.

  Fig. 6 is a perspective showing an alternative embodiment of the panel

illustrated in fig. 1.

  A reinforced metal panel, according to the invention, as illustrated in FIG. 1 and designated as a whole by the reference 1, comprises at least two and, according to the illustrated example, exactly two external walls 2 and 3 substantially

parallel to each other.

  According to an essential characteristic of the invention, the walls

  2 and 3 are braced by an intermediate or corrugated inner wall 4.

  As is more particularly apparent from FIG. 2, the vertices 5 of the waves of the intermediate wall 4 are each in contact with the inner face 6 of one of the outer walls 2, 3. At least some of the vertices 5 and, preferably, all the vertices 5 are attached to the external wall 2 or 3 corresponding. According to the illustrated example, the undulations of the intermediate wall 4 have a substantially trapezoidal shape, so that the top 5 of the waves or undulations, formed by the small base of the trapeziums, is substantially flat. In a preferred manner, the trapeziums, defined by the undulations of the intermediate wall 4, are substantially isosceles and the waves of the wall 4 are repeated at an appropriate pitch X and in accordance with the mechanical requirements. Preferably, but not strictly necessary, the step k substantially respects the relationship: 1.6 d <?, <3.4 d

  o d is equal to the distance between the inner faces of the two outer walls 2 and 3.

  Furthermore, the corrugations of the intermediate wall 4 are shaped so that the peaks 5 of the corrugations form, with an adjacent side 7 of the trapezium, an appropriate internal angle a and in accordance with the mechanical requirements and preferably but not necessarily between 25 and 75. Preferably, the corrugations of the intermediate wall 4 are shaped so that the length I of the small base 5 of the trapeziums and the length L of the large base 8 of the trapezoids satisfies the relationship:

L = (3/2) 1

  According to the illustrated example, the outer walls 2 and 3 of the panel 1 are substantially flat, so that the reinforced panel 1 has a generally parallelepipedal general shape. Preferably, the small side faces 10 of the panel 1 are closed, while the large faces 11, being substantially

  perpendicular to the intermediate wall 4, are open.

  According to the illustrated example, the small faces 10 are closed by a folded edge 13 of one of the outer walls 2 or 3, this folded edge being fixed on a straight edge 14 provided by the other outer wall. Thus, according to the illustrated example, each external wall 2, 3 has a straight edge 14 and, opposite this straight edge, an edge 13 folded substantially at right angles to the outer wall 2, 3 and fixed on the right edge 14 opposite the other outer wall, respectively 3 and 2. This advantageous arrangement of the invention makes it possible, in a simple and inexpensive way, a possible catch-up of the game resulting from minor dimensional defects likely

  to have appeared during manufacture.

  A reinforced metal panel 1, as previously described and illustrated in FIGS. 1 and 2, is particularly adapted to be manufactured as part of an automatic or semi-automatic production plant, as illustrated

  schematically in fig. 3 and referred to as a whole by reference 20.

  The installation 20 then comprises a storage station 21 of sheet blanks, from which the blanks are transferred to at least one and, according to the illustrated example, three cutting units 22, 23, 24 which are each adapted to cut each sheet blank to the respective dimensions of the developed outer walls 2, 3 and

the intermediate wall 4.

  The first cutting unit 22, at which the developed one outer wall 2 is formed, is followed by a first manufacturing station 26 of the first outer wall comprising means 27 for supporting the sheet blank 25. cut to the dimensions of the developed first outer wall 2. The support means 27 include, for example but not exclusively, a roller conveyor and a gripping automat handling. The first manufacturing station 26 also includes means, not shown, for shaping the sheet blank 25, such as, for example, a folder for folding the edge 13. Thus, the first outer wall 2, completely confined is available in

output from the manufacturing station 26.

  The installation 20 also comprises a second manufacturing station 28 of the second outer wall 3. The station 28, located after the third cutting unit 24, then comprises means 29 for taking charge of a sheet blank 30 cut to the dimensions of the developed second outer wall 2, by the cutting unit 24. The support means 29 include, for example but not exclusively, a roller conveyor and a handling gripper. The manufacturing station 28 further comprises means, not shown, for shaping the sheet blank and, in particular, for folding the edge 14 of the blank.

this last.

  The installation also comprises a third manufacturing station 31 of the intermediate wall 4. The third manufacturing station 31, located after the second cutting unit 23, then comprises means 32 for taking care of a blank sheet 33 cut to the dimensions of the developed intermediate wall 4 by the second cutting unit 23. The station 31 also comprises means, not shown, for shaping the sheet blank 33, such as, for example, a folder or a stamping machine adapted to produce the corrugations of the intermediate wall

  4. The second station 28 then finalizes the manufacture of the intermediate wall 4.

  The installation 20 then comprises a primary assembly station 35 comprising support means, not shown, on the one hand, of the first outer wall 2 from the first manufacturing station 26 and, on the other hand, hand,

  of the intermediate wall 4 from the third manufacturing station 31.

  Thus, at the station 35, the intermediate wall 4 is placed on the first outer wall 2. The primary assembly station 35 has, in addition, means, not shown, for assembling the first outer wall with the first intermediate wall. The assembly means are, for example, constituted by spot welding means which then ensure, at each of the vertices 5 of the intermediate wall 4 in contact with the first outer wall 2, one or more rows of dots. 36 weld aligned, as shown more

particularly FIG. 1.

  Of course, according to the invention, the assembly by welding is not strictly necessary and the primary assembly station 35 could include means for depositing, ad hoc or continuous, glue on the inner face of the outer wall 2 and / or on the tops of the intermediate wall 5, before assembly thereof. At the output of the manufacturing station 35 is obtained a primary assembly 37 formed

  the outer wall 2 and the intermediate wall 4 fixed to one another.

  The primary assembly station 35 is then followed by a secondary assembly station 38 at which the second outer wall 2 is assembled at least with the intermediate wall 4 of the primary assembly 37. The secondary assembly station 38 then comprises means, not shown, for supporting the primary assembly 37, on the one hand, and the second outer wall from the second manufacturing station 28, on the other hand. The secondary assembly station 38 then comprises means for assembling the second outer wall with at least the intermediate wall of the primary assembly. These assembly means are, for

  example, made in the form of a position or a spot welding machine.

  Thus, at the output of the secondary assembly station, a reinforced panel is obtained,

as shown in figs. 1 and 2.

  The reinforced panels 1, thus manufactured in accordance with the invention, can be used for various applications such as, for example, the production of

  chassis or structures to withstand significant stresses.

  In a preferred application, the panels 1 are used for the realization of a submerged transformer tank, as schematically illustrated in FIGS. 4 and 5. Such a tank 40 then comprises a bottom 41 from which rise four side walls 42, 43, 44, 45 which give the tank a cross section substantially rectangular, as shown in FIG. 4. According to the illustrated example, the side walls 41, 42 to 45, are each formed by a reinforced metal panel 1 according to the invention. Each panel 1 is then fixed, at one of its longitudinal faces 11, on the bottom 41 and, preferably, welded in a sealed manner to the latter. Each reinforced panel 1 is, moreover, fixed at one of its small side faces 10 on an outer wall of an adjacent side panel and, at its opposite end, by one of its outer walls on the small side face 10 of a second adjacent side panel. This method of assembly allows to respect, quickly and without difficulty

  of adjustment, the dimensional dimensions of the interior of the tank.

  Of course, according to the invention, the reinforced metal panels 1 could also be used for the realization of the bottom 41 of the tank depending, in particular, the load to be supported by the latter. Furthermore, the honeycomb character of the panels according to the present invention allows the introduction into the wall that they form materials for soundproofing the tank and reduce vibration related to the operation of the transformer that will be placed in the tank. Thus, it would be possible to envisage filling the honeycomb panels according to the present invention with sand or else

Rockwool.

  Similarly, insofar as the structure of the honeycomb panel according to the invention allows a lightening of the constituent materials of the panel, it is possible to use for manufacturing the cellular panels nonmagnetic materials such as non-magnetic steels or aluminum without that the panels thus produced have a cost prohibitive. The implementation of such non-magnetic materials then makes it possible to avoid expensive magnetic screens and

  bulky items often installed inside the transformer tanks.

  According to the examples illustrated above, the small side faces 10 of the reinforced panel 1 are each closed by a folded edge 13 extending from a separate external wall 23. However, such a configuration is not strictly necessary for the realization a reinforced metal panel according to the invention. Thus, according to FIG. 5, the edges 13 are both folded from a

same outer wall 3.

  Similarly, the side faces 10 and 11 of the reinforced panel according to the invention could also be closed by means of inserts and welded to the

  level of the sides of the faces of the outer walls 2 and 3.

  Of course, various other modifications can be made to

  invention without departing from its scope.

Claims (11)

  1 - reinforced metal panel for the manufacture of metal tanks in particular, characterized in that it comprises at least two outer walls (2, 3) substantially parallel to each other and braced by an intermediate wall (4) corrugated and fixed at the level of at least some of the peaks (5) of its waves, at   corresponding outer walls (2, 3).   2 - reinforced metal panel according to claim 1, characterized in that the   vertices (5) waves of the intermediate wall are flat.   3 - reinforced metal panel according to claim 1 or 2, characterized in that the corrugations of the intermediate wall (4) have, in cross section   transverse, a substantially trapezoidal shape.   4 - Reinforced metal panel according to claim 3, characterized in that the small base (5) of the trapeziums forms, with the sides, an internal angle is between 25 and 75.   Reinforced metal panel according to one of Claims 1 to 3, characterized   in that the corrugations have a pitch X which substantially respects the relation: 1,6d <X <3,4d   o d is equal to the distance between the inner faces (6) of the two outer walls.   Reinforced metal panel according to one of claims 1 to 5, characterized   in that at least one of the outer walls (2, 3) has at least one edge (13)   folded and welded at the end (14) facing the other outer wall (2, 3).   7 - reinforced metal panel according to claim 6, characterized in that the two outer walls (2, 3) each have, on the one hand, a straight edge and, on the other hand, opposite the right edge, a folded edge (13) and welded to right edge (14), facing from the other outer wall.   8 - reinforced metal panel according to one of claims 1 to 7, characterized   in that the outer walls (2, 3) are substantially planar.   9 - reinforced metal panel according to one of claims 1 to 8, characterized   in that the vertices (5) of the waves are welded to the corresponding outer wall (2, 3). he   Reinforced metal panel according to one of claims 1 to 8, characterized   in that the vertices (5) of the waves are glued to the corresponding outer wall (2, 3). 11 - submerged electric transformer tank, of the type comprising a bottom (41) and at least one side wall (42, 43, 44, 45), characterized in that the lateral wall (42) or the bottom (41) comprises at least one least one reinforced panel (1) according to one of Claims 1 to 10.   12 - electric transformer tank according to claim 11, characterized in that the tank (40) has a rectangular cross section and in that the side walls (42, 43, 44, 45) of the tank are each formed by a sign   reinforced metal (1) according to one of claims 1 to 10.   13 - electric transformer tank according to claim 11 or 12 characterized in that the reinforced panel or panels are filled with a material absorbing vibrations.   14 - Process for manufacturing a reinforced metal panel according to one of the   Claims 1 to 10, characterized in that it consists in particular of, successively:   * cut three blanks of sheet metal to the dimension of the developed two outer walls (2, 3), on the one hand, and the intermediate wall (4), on the other hand, * distribute the three blanks on three bets in separate form (26, 28, 31),   * proceed, on each station, the shaping of the corresponding blank, * assemble the intermediate wall (4) shaped with an outer wall (2) to obtain a primary assembly (37), * assemble the other outer wall (3) ) with the primary assembly (37) for   obtain the reinforced metal panel (1).   - Installation for the implementation of the manufacturing method according to claim 14, characterized in that it comprises: * at least one unit (22) for cutting sheet blanks to the developed dimensions of the outer walls and the intermediate wall a first station (26) for manufacturing a first external wall (2) comprising means for supporting a blank of sheet metal (25) cut to the dimensions of the developed part of the first external wall (2), and that means for shaping the sheet blank, ò a second station (28) for manufacturing the second outer wall (3) comprising means for taking care of a sheet blank (30) cut to the dimensions of the developed of the second outer wall (3), as well as means for shaping the sheet blank, ò a third station (31) for manufacturing the intermediate wall (4) comprising means for taking care of a blank of sheet (33) cut to the dimensions of the developed wall intermediate, as well as means for shaping the sheet blank (33), * a primary assembly station (35) comprising means for taking care, on the one hand, of the first outer wall (2) to from the first manufacturing station (26) and, on the other hand, from the intermediate wall (4) from the third manufacturing station (31), and from the means for assembling the first outer wall (2) with the intermediate wall (4) to form a primary assembly (37), * a secondary assembly station (38) comprising means for taking care, on the one hand, of the primary assembly (37) consisting of the first outer wall (2) and the intermediate wall (4) and secondly the second outer wall (3), and means for assembling the second outer wall (3) at least with the intermediate wall. (4) the primary assembly (37).