FR2776420A1 - Rectangular container for transformer windings - Google Patents

Abstract

The use of aluminium profile provides heat dissipation without corrosion.- DETAILED DESCRIPTION - The container for a transformer comprises side walls, a base and a cover plate forming a rectangular box. The side walls are formed from two types of section comprising aluminium profiles. The first type (15) is straight in order to provide the sides of the container, and the second type (16) is angled in order to form the right angle corners of the container. The profiles include mortise and tenon type joints (17,18) on abutting edges in order to link them together. The straight sections (15) include a set of parallel external cooling fins (19) formed within the shaped profile.The sections also have holes provided to receive the screws which retain the container base

Description

Transformer tank and assembly method

  The present invention relates to a transformer tank.

  A known construction of the transformer tank consists in that each of the four lateral faces is made of sheet steel, pleated so as to form cooling fins. At their upper and lower ends, the edges of the folds are brought together and welded. The four faces are assembled and welded, then a bottom is welded to this assembly, while at the upper end is welded an L-section flange to which is fixed, by screwing, a cover with

interposition of a joint.

  Such a construction requires a very large welding job, presents a

  significant weight and poses problems of corrosion by oxidation.

  The object of the present invention is to overcome these drawbacks, and in addition, to

  for the advantage of reducing the size of the tank.

  We will now give the description of an example of implementation

  of the invention with reference to the accompanying drawing in which: FIG. 1 schematically shows a top view of a

  transformer according to the invention, without its cover.

  Figure 2 shows the tank in elevation.

  Figures 3 and 4 are enlarged portions of the parts marked III and IV of

Figure 2.

  Figure 5 shows a top view of the two types of profiles used for

  make the side walls of the tank.

  Figure 6 shows in perspective three straight sections assembled, and on which were drilled holes at the upper and lower ends of the

profiles.

  Thus, referring to FIGS. 1 to 5, we see a transformer tank 1, in which the windings 2, 3, 4 of the transformer have been shown in fine lines in FIG. 1 as well as the low voltage terminals 5, 6, 7, 8 and high

  voltage 9, 10 and 1 1 in Figure 2.

  The transformer tank 1 has side walls 12, as well as a

  bottom 13 and a cover 14. It contains a liquid dielectric 20.

  According to the invention, the side walls 12 are made up of two types of aluminum profiles, shown in FIG. 5: straight profiles 15 and

corner profiles 16.

  These profiles are made of extruded aluminum, cut to the desired length and assembled. We can thus make tanks of different dimensions by assembling

  more or less straight sections 15, an angle section 16 being located at each corner.

  For assembly, each profile has at its two lateral ends an assembly section: on one side, a male part such as a stud 17, and on the other, a complementary female part such as a mortise 18 The assemblies are glued. The straight sections 15 have cooling fins 19. Furthermore, the straight and corner sections have vertical channels 21 for the circulation by thermo-siphon of the dielectric liquid.

o10 20.

  For fixing the cover 14 and the bottom 13, vertical passages 22 separate the channels 21. They allow either the passage of tie rods 23 or the use of self-tapping screws 24, which are screwed by tapping the wall 25 of the vertical passages 22. In practice, one can alternatively put a tie rod, then a screw. A

  flat seal 26 is located, on the one hand under the cover, and also under the bottom 13.

  Figures 3 and 4 show the detail of the fixing of the cover and the bottom

by screw 24 and pulling 23.

  To allow the passage of the dielectric liquid 20 in the vertical circulation channels 21 of the straight sections 15 and also of angle 16, orifices 27 are drilled at the lower and upper ends of the channels. These holes are

  shown in Figure 6 o there are shown three straight sections 15 assembled.

  In this figure, the arrows shown represent the direction of movement of the

dielectric liquid.

  The transformer tank is thus made in the following way: the sections 15 and 16 are cut to the desired length, the holes 27 are drilled, the straight sections 15 are assembled, so as to constitute the four lateral faces of the

  tank, then these four faces are assembled with the corner profiles 16.

  The flat seal 26 is then deposited against the upper end and against the lower end of the assembly before applying the bottom 13 and the cover 14 which are fixed by the screws 24 or the tie rods 23 or by a combination of the two. . In practice, we prefer to use both so that, when the transformer is lifted by the cover, the force is not only on the screws,

  but also taken up by the tie rods and the bottom 13.

  At 28, there are shown profiles on which the transformer rests

  allowing it to be moved by means of forks.

  Thus, with such a tank, there is no longer any welding, there is no more corrosion by oxidation, since the side walls are made of aluminum, as well as the bottom and the cover, the assembly is therefore also very much lighter and moreover, less bulky, since aluminum having better thermal conduction than steel, the cooling fins 19 are less deep. The size of the tank is adjustable according to the size of the transformer,

  more or less straight sections are assembled.

Claims (7)

  1 / transformer tank (1) comprising side walls (12), a bottom (13) and a cover (14), characterized in that the side walls (12) consist of two types of aluminum profiles: profiles straight (15) and corner profiles (16) for the four angles, the lateral ends of the profiles having an assembly section (17, 18) allowing the successive assembly of the various profiles between them.   2 / transformer tank according to claim 1, characterized in that   the assembly of the profiles together is glued.   3 / transformer tank according to claim 1, characterized in that said   straight sections (15) have cooling fins (19).   4 / transformer tank according to one of claims 1 to 3, characterized in that   that said sections include vertical channels (21) for the circulation of dielectric liquid (20).   5 / Method of assembling a transformer tank according to one of the   previous claims, characterized by the succession of the following steps   a) cutting the profiles (15, 16) to the desired length, b) assembling the straight profiles (15) so as to constitute four lateral faces of the tank (1), c) assembling the lateral faces with the corner profiles (16), d) removal of a seal (26) at the upper end and at the lower end of all of the assembled profiles,   e) fixing the bottom (13) and the cover (14) to the assembly.   6 / A method according to claim 5, characterized in that between operations a) and b) takes place a hole drilling operation (27) at the lower ends and   upper of said vertical channels (21).   7 / A method according to claim 5, characterized in that the fixing of step e) is carried out by tie rods (23) passing through vertical passages (22) separating two successive circulation channels (21) and / or by auto screws - tapping machines (24)   "Biting" in the wall (25) of said vertical passages.