MXPA96001874A - Procedure for closing a tubular wall from an ac changer fluid box - Google Patents

Abstract

The tubular wall is formed by winding a sheet whose two opposite edges (4, 6) are related to one another by their edges, and are joined in a sealed manner by welding, according to the invention, one (4) of said edges has protrusions (3), which will be housed in conjugate holes in the other edge (6) so as to prevent mutual separation during welding, has application to fluid boxes of lime exchangers

Description

PROCEDURE TO CLOSE. A TUBULAR WALL OF A HEAT EXCHANGER FLUID BOX DESCRIPTION OF THE INVENTION The invention relates to a method for obtaining a tubular wall in which a sheet is rolled to the shape of a cylinder, so that two opposite edges thereof are facing each other by their edges; 30 being spaced apart only by a set which is not greater than a few hundredths of a millimeter, and a solder material is made to seal said set and seal the edges together. A process of this type is described in EP-A-0 t 351 3ñ for obtaining the tubular side wall of a cs a of fluid from the heat exchanger. In said known method, the two opposite edges are rectilinear and can deviate locally from one another in a circumferential direction, after a deformation of the sheet generated by the heat 50 of the weld. Particular arrangements are foreseen, in the cited document, for example, a bevel cutting of the edges, to allow their joining by welding, in spite of said def orm ion. However, it is preferable, both for the appearance of the finished wall, and for the safety of the welded seam, to prevent said deformation, as well as to limit its consequences. This is the objective of the present invention. The invention mainly contemplates a procedure of the genus defined in the introduction, and provides c. that said edges present non-rectilinear, mutually conjugated traces, which define contrary elements that prevent > the edges deviate from each other in an ircunferential direction, before welding is obtained. Other optional features of the invention, complementary or alternative, are mentioned below: the two edges respectively have protrusions and recesses suitable for receiving the projections. - Each projection or each recess has a neck that connects to a head; turning his head towards the 1 outside the sheet, in relation to the neck, in the case of a projection; and towards the inside of the sheet, in relation to the neck, in the case of a cupping; and extending beyond the neck, in one direction and in the other, in the longitudinal direction of the edge. < --0 The projections and the hollows occupy a minority fraction of the length of the edges; being these rectilinear in the remaining fraction of their length. - Several projections or hollows are distributed along an edge, at mutual distances that are not greater than 60 '^ 5 m, approximately. - The sheet is first rolled up so that the rectilinear regions of the edge, in which there are projections, coincide with the recumbent legions of the edge, in which the recesses are; the projections being substantially tangential on the outside of the cylinder, and then the projections are pressed radially to insert them into the recesses. - Said welding material is arranged in the manner of a coating on 1 minus one of the faces of the sheet, before winding it to a cylinder. - The procedure for obtaining the tubular side wall of a heat exchanger fluid box comprises? the following steps: a) the sheet is curved in a band located in the mind < half the distance between said edges; b) are formed in the curved middle band, openings for the passage of the fluid circulation tubes, intended to be connected to the fluid box; and c) rolling of the sheet is continued, so that said edges are mutually joined in an area of the tubular wall substantially diametrically opposite to said currents. The invention also has as its purpose a tubular wall, especially for a flow of heat from a heat exchanger, constituted by a sheet wound to the shape of a cylinder, so that two opposite edges thereof are joined together by their songs; said edges being connected to each other in a sealed manner and solidary by a welding material. According to the invention, said edges present non-interacting, mutually conjugated traces, defining c-. appropriate counter elements to ensure a mutual locking of the edges in the cial direction. The characteristics and features of the invention will be explained in more detail in the following description, with reference to the attached drawings, in which: FIG. 1 is a top view of a tubular fluid box wall according to the invention; . Fig. 2 is a top view of a sheet plate used to form the wall of Fig. 1. Fig. 3 is an enlarged detail of Fig. 2. Fig. 4 is a cross-sectional view of the sheet, in a intermediate stage of the process according to the invention; and Figure 5 is a partial cross-sectional view, related to another stage of the procedure. Figure 1 represents a tubular iatetal wall 1 for a heat exchanger fluid outlet, having the same general shape as that described in EP-A-0 351 93A. Said tubular wall is obtained from a sheet metal plate 2, generally rectangular in shape, which is illustrated in FIG. 2. Projections 3 are provided, at mutual distances of the order of 60 m along a longitudinal edge 4- of the sheet 2. With respect to each projection 3, a recess 5 is provided on the longitudinal side 6 opposite to the side 4. The projections 3 are joined together by portions of? edge 7 which are understood following the same straight line, parallel to the general direction of sides 4 and 6. The same applies to the edge portions & that join the hollows or resaques 5. The projections 3 have a conjugated form with the one of the cupping S, so that it? they lodge in these, with a set that is not greater than a few hundredths of a millimeter, when the tool is wound around an axis 9, to provide the edge portions 7 in coincidence with the edge portions ñ, as shown in FIG. the figu al. The shape common to the projections 3 and the recesses 5 is illustrated in Figure 3, which more particularly represents a projection 3. This is formed by a head 10 / a neck 1 which connects the head with the rest of the sheet, join directly to edge portions? rectilinear 7 by rounding 12. The head 10 extends beyond the neck 11 in the longitudinal direction of the edge 4, both in one direction co or the other (upwards and downwards, when seen in figure 3). The shape of projection 3, therefore, is similar to that of a tail of? milano, and presents contrary elements 13, but devoid of sharp angles. In Figure 1 it is seen that openings 14 are provided through the wall 1, for the passage of the tubes for the flow of liquid in the heat exchanger. Said openings 14 are aligned following a generatrix diametrically opposite the edge portions 7 and & Preferably they are formed by punching when, as seen in Figure 4, the corresponding region 15 of the sheet, the sheet has already been curved following the radius of the final tubular wall, the adjacent regions 16 and 1 / extend following planes tangent to the curved region 15. Finally, Figure 5 shows the sheet when it has been rolled, by means of an appropriate punch, over its entire surface comprised between the straight lines containing the portions of the edges 7 and &; the projections extending tangentially with respect to the cylinder thus formed, from the portions 7. The projections 3 are then, partially, radially on the outside of the cylinder and of the recesses 5. A pressure exerted by a die , following the direction of the arrow F, on the projections., allows all of them to enter the inside of the hollows. As you know, the edges 4 and 6 are then sealed together by melting a welding material covering at least one of the faces of the sheet 2, before winding. In the case of the invention, said welding material also fills the gaps or spaces between the projections 3 and the recesses 5, as well as the rectilinear portions 7 and ñ. The rolling of the sheet can be carried out with the aid of any known tool.

Claims (7)

& NOVELTY of the INVENTION CLAIMS

1. - Procedure to form a tubular wall, in which a sheet is rolled to the shape of a cylinder, of? so that two opposite edges of the same are one in relation to the other by their edges, which are only separated by a game no greater than a few hundredths of a millimeter, and it makes melt a welding material to fill in a sealed manner said game and solidarizar the edges between if; characterized said procedure because the edges present traces not ectilmeos, mutually conjugated, what? they define contrary elements that prevent the edges from deviating from each other in the ircunferential direction, before welding is obtained. 2.- Procedure according to the indication 1, characterized further because the two edges have, respectively, protrusions and holes, suitable to receive the projections. 3. Method according to claim 2, further characterized in that each projection or each recess has a neck that is joined to a head; the head being turned towards the outside of the sheet with respect to the neck, in the case of a projection; and towards the inside of the sheet, in relation to the neck, in the case of a cupping, and extending beyond the neck, in one direction and in the other, with the longitudinal direction of the edge. 4.- Procedure according to any of the claimed ions? v 3, also acte ized because the 5 projections and the holes occupy a minority fraction of the length of the boiaes; being these rectilinear in the remaining fraction of their length. 5. Procedure according to the i and v ind ica tion 4, further characterized by vain projections or hollow spaces i'.1 are distributed along an edge, at mutual distances that are not more than t > ? mm, approximately. 6. Process according to any of the claims 4 S, further characterized in that the sheet is rolled first so as to provide the rectilinear regions of the edge provided with projections, in coincidence with the regions lecti lines of the edge provided with holes; the substantially tangential projections extend to the outside of the cylinder, and the projections are then pressed radially to enter the recesses. 7. Method according to any of the preceding claims, characterized in that said welding material is arranged in the manner of a recess on at least one of the faces of the sheet, before rolling it to a cylinder. 5 & . - Method according to any of the preceding claims for the formation of the side tubular wall of a heat exchanger fluid box. 9. Process according to claim ñ, further characterized in that they comprise the following steps: a) the sheet is curved in a band substantially equal to half the distance between said edges; b) are formed in the middle, curved band, openings for the passage of the fluid circulation tubes, intended to be connected to the fluid box; and e) the winding of the sheet is continued so that said edges can be mutually joined in a zone of the tubular wall substantially opposite to said openings 10. Tubular wall, especially for a fluid box heat exchanger, constituted by a sheet rolled into the shape of a cylinder, so that two edges 15 opposites of it are related to each other by their songs; said edges being joined together in a sealed manner and joined by a welding material; characterize said wall because the edges present non-rectilinear traces, mutually conjugated, that define opposite elements, 20 appropriate to ensure a mutual locking of the edges in the ircun direction erenc al. 11. Tubular wall according to claim 10 ,. further characterized because the edges are as defined in any of the claims 2 to 5 and / or in step c) of claim 9. PROCEDURE FOR CLOSING A TUBULAR WALL FROM A HEAT EXCHANGER FLUID BOX SUMMARY OF THE INVENTION The tubular wall is formed by winding a sheet whose two opposite edges (4, 6) are related to one another by their edges, and are joined in a sealed manner by welding; according to the intention, one (4) of said edges has projections < 3), which will be housed in conjugate holes in the other edge (6) so as to prevent their mutual separation during welding; It has application to heat exchanger fluid boxes. CR