ES2698099T3 - Heat exchanger and method for manufacturing a heat exchanger - Google Patents

Abstract

A heat exchanger comprising a plurality of pairs of heat exchanger plates (1), formed of sheet metal, having a three-dimensional structured pattern (2, 3), a first flow path that is defined within the plurality of said pairs and a second flow path that is defined between said pairs, wherein each plate (1) has at least one through opening (5-8), where said through opening (5-8) is surrounded by tongues (10, 12, 13) cut from the area of the through opening (5-8) and bent outwards, where the tongues (10, 12, 13) of a plate (1) are inserted in the through opening of a neighboring plate (1b) , where said languages of a plate (1a, 1b) are connected to the languages (12, 13) of a neighboring plate (1b, 1c), characterized in that the languages (10) are cut with a radial component of the vector other than zero to have a triangular shape, where these languages (10, 12, 13) have a length, being dic has length at least twice a distance (16) between neighboring plates (1a, 1b).

Description

DESCRIPTION

Heat exchanger and method for manufacturing a heat exchanger

The invention relates to a heat exchanger comprising a plurality of pairs of heat exchanger plates, formed with metal sheet, having a three-dimensional structured pattern, a first flow path that is defined within the plurality of said pairs and a second flow path that is defined between said pairs, wherein each plate has at least one through opening. From GB 2,026,676 A a heat exchanger and a method for manufacturing a heat exchanger according to the preamble of claims 1 and 7 are known, respectively. In addition, the invention relates to a heat exchanger plate, formed with metal sheet, having a three-dimensional structured pattern and having at least one through opening.

The invention also relates to a method for manufacturing a heat exchanger forming a stack of pairs of heat exchanger plates, formed with sheet metal, having a three-dimensional structured pattern, wherein each plate has at least one through opening.

A heat exchanger is also known from US 2007/0261829 A1. The heat exchanger plates of this heat exchanger have a three-dimensional structured pattern comprising bulges and voids. The bulges and voids are placed against the respective recesses and bulges of an adjacent heat exchanger plate, to form the flow path on the main and secondary sides of the heat exchanger.

Other kinds of heat exchanger plates comprise a spike-like pattern.

A heat exchanger requires four connections, that is, two pairs of connections. A pair of connections is necessary for the main side, that is, a supply connection and a return connection. The other pair of connections is necessary for the secondary side, that is, to receive and return the fluid that should be heated or cooled with the help of the heat exchanger.

In many cases, the connections are made with the help of drills that pass through them, which are called abbreviated "through openings". These through openings are arranged in the corners of the heat exchanger plates. It is necessary to form a heat exchanger, formed by a stack of plates, such that the inlet and outlet channels defined by the through openings are strong enough to withstand even substantially high fluid pressures. In particular, in relation to dimple heat exchangers of the type described in US 2007/0261829 A1, the channels have to withstand relatively high pressures.

In known heat exchangers, the neighboring heat exchanger plates have been connected in the area of the through openings by means of various welds surrounding the through openings. However, it is difficult to make such a connection strong enough to withstand the high pressure.

The objective behind the invention is to have a solid connection between adjacent heat exchanger plates in the area of the through opening.

This objective is achieved by the fact that said through opening is surrounded by tongues cut from the area of the through opening and bent outwards, where the tongues of a plate are inserted in the through opening of a neighboring plate.

The material that must be removed to form the through opening is no longer wasted. This is used to form a wall that surrounds the through opening and consists of separate languages. When the tongues of a plate are introduced into the through opening of the neighboring plate a kind of cylinder is formed which extends through the through openings, thus forming a stable channel in the area of the opening to withstand the relatively high pressures. The tongues have a length, said length being at least double a distance between neighboring plates. In this way, the neighboring plate languages can be superimposed over a relatively long distance, which can be used to make a connection between adjacent plates sufficiently stable. The languages of a plate are connected to the languages of a neighboring plate. Said connection can be made, for example, by welding. The tongues of the plates form a chain that holds the heat exchanger plates together even when the pressure between the plates is relatively high. Another possibility would be to braze the languages together.

Preferably, the neighboring plate languages form connection areas, where the adjacent connection areas are separated from each other. This simplifies forming the connection between neighboring languages. In each connection area only two languages are connected, so it is relatively simple to form the connection and check the connection. The languages have a triangular shape. This simplifies generating the languages by cutting lines that run diametrically through the through opening. For example, when four lines are used of cutting eight tongues are generated that can be bent perpendicularly to the plane of the heat exchanger plate.

Preferably, said neighboring plate languages have the same angular position with respect to said through bore. When the heat exchanger plates are assembled to form a stack, each tongue is superimposed on a tongue disposed at the same angular position of an adjacent plate. This leads to an area of maximum overlap between adjacent plate languages.

Preferably, an end plate having a bulge adapted to receive the tongues of at least one heat exchanger plate adjoining said end plate is provided. In a system that has a stack of heat exchanger plates with bent tongues a problem may arise in the lower plate, where there is no neighboring plate. One solution is to arrange a bulge in said plate, which is adapted to receive the bent tongues of at least one heat exchanger plate adjoining said final plate. In this case, the heat exchanger plate adjacent to the end plate may have the same shape as all the other heat exchanger plates of the heat exchanger. Preferably, the bulge is adapted to receive the tongues not only from the heat exchanger plate adjoining said final plate, but also to the tongues of at least the second heat exchanger plate counted from the end plate.

Preferably, said bulge has a depth, said depth being greater than a height of said tongues perpendicular to said heat exchanger plate adjoining said final plate. In this case, the languages can remain in their vertical state, that is, it is not necessary to deform the languages. In any case, the tongues can be connected to the wall of the bulge.

In an alternative embodiment, the tongues of a heat exchanger plate adjoining a final plate are bent, at least at their end, parallel to said end plate. These tongues are bent at least twice, comprising a first section almost perpendicular to the plane of the heat exchanger plate and also comprising a second section parallel to the plane of the end plate.

In this case it is preferred that the tongues of at least two heat exchanger plates adjoining said end plate form, at least at their ends, a layered structure on an inner surface of said end plate. This layered structure can be easily connected to said final plate.

The objective is achieved with a heat exchanger plate of the type mentioned above, in that said through opening is surrounded by tongues cut from the area of the through opening and bent outwards.

In most cases, for the manufacture of the heat exchanger plate it is necessary to mold the plate in a press. This press can be used to cut the tongues and fold them out, p. eg, almost perpendicular to the plane of the plate. These languages facilitate the assembly of the plate to form a stack of plates, since the tongues can be used as auxiliary means to align the plates.

The objective is achieved by a method for manufacturing a heat exchanger, such as the one mentioned above, in that said through opening is formed by cutting the sheet of material in the area of the through opening to form the tongues and bending out said languages

In this way, the tongues can be used to facilitate the assembly of the stack of heat exchanger plates. The tongues can be used to connect the heat exchanger plates in the area of the through openings. The tongues of a plate are introduced into the through opening of a neighboring plate. This means that the languages of a plate overlap the languages of neighboring plates along a predetermined distance. This overlapping area offers a relatively stable and pressure-resistant connection between neighboring heat exchanger plates. The languages of a plate are connected to the languages of the neighboring plate. The connection between the tongues can withstand the tensile forces generated by the pressures inside the heat exchanger.

Next, a preferred example of the invention will be described in more detail with reference to the drawings, where:

Figure 1 is a plan view of a heat exchanger plate not according to the invention, Figure 2 is an enlarged view of the upper right corner of the heat exchanger plate of Figure 1,

Figure 3 is a view of an arrangement of a plurality of plates before bending out the tongues,

Figure 4 is a view of an arrangement of a plurality of plates in which each has tongues, Figure 5 shows an example of another form of the languages according to the invention,

Figure 6 shows an example of connection of languages with a lower plate and

Figure 7 shows an alternative to the embodiment of Figure 6.

Figure 1 shows a heat exchanger plate 1 as shown in US 2007/0261829 A1. This plate 1 comprises bulges 2, which rise to a given height above the plane of the heat exchanger plate 1. Furthermore, the heat exchanger plate 1 comprises recesses 3, which are sunken to a given depth in this heat exchanger plate 1. The bulges 2 are symbolized by white circles, while the holes 3 are symbolized by circles with a cross. As described in US 2007/0261829 A1, two of said plates 1 form a pair of plates, in which a heat exchanger plate 1 is rotated approximately 180 ° on its longest edge 4. A plurality of said pairs are stacked on top of each other. A first flow path is formed within these pairs and a second flow path is formed between these pairs.

The heat exchanger plate 1 is made with sheet metal. A metal sheet is a material that has a good thermal conductivity and can be formed in a press or matrix. It is also possible to use plastic materials instead of metal sheet. The bulges 2 and the recesses 3 form a structured three-dimensional profile. This profile is created in a press or matrix.

The heat exchanger plate 1 comprises four through openings 5-8. These through openings 5-8 are used to form channels or connections. For example, the through openings 5, 7 form a supply and return for the first flow path, and the through openings 6, 8 form a supply and return for the second fluid path.

In Figures 1, 2 and 3 the through openings 5-8 are still closed.

Figures 2-4 show a way to open the through openings 5-8 not according to the invention, Figures 3 and 4 show a stack of three heat exchanger plates 1a, 1b, 1c.

In a first step four cuts are made running diametrically in the area of the through opening 5. The four cut lines 9 are shown in figure 2. When the cuts have been made, the area of the through hole 5 is covered by eight languages 10. Each language has an almost triangular shape. In a next step the tongues 10 are bent out of the plane of each heat exchanger plate 1a, 1b, 1c, so that the tongues 10 are disposed almost perpendicular to the plane 11 of the heat exchanger plate 1. This is shows schematically in Figures 3 and 4. The bend does not generate a sharp edge but a rounded transition between the plane 11 and the tongue 10. Preferably, the cutting and bending of the tongues 10 is carried out before the plates are stacked of heat exchanger 1a, 1b, 1c.

When the plurality of heat exchanger plates 1a, 1b, 1c are arranged one above the other in order to form a stack, the tongue 10 of the heat exchanger plate 1a is superimposed on the tongue 12 of the exchanger plate of heat 1b adjacent. This tongue 12 overlaps the tongue 13 of the next adjacent heat exchanger plate 1c.

The languages 10, 12 form an area of superposition 14 in which the languages 10, 12, p. eg, by welding. The languages 12, 13 form an area of superposition 15 in which the languages 12, 13, p. eg, also by welding.

As shown in FIG. 4, the areas of superposition 14, 15 (which may also be referred to as connection areas) are separated from each other, that is to say, in each superposition area 14, 15 only two languages are superimposed on each other. , 12 or 12, 13, respectively.

The tongues 10, 12, 13 have a length that is at least twice a distance 16 between the adjacent or adjacent heat exchanger plates 1a, 1b. This makes the superposition area 14, 15 large enough.

The tongues 10, 12, 13 of all the heat exchanger plates 1a, 1b, 1c have the same angular orientation with respect to the through opening 5. In this way, the end of a tongue 10, 12 always overlaps with a base of the following language 12, 13. In this way a very reliable connection between the languages can be established.

If necessary, this connection can be made for all through openings 5-8.

Sealing means (not shown) can be arranged around the tongues, between the neighboring heat exchanger plates 1a, 1b, 1c, since the connection of the languages 10, 12, 13 is not necessarily leak-proof per se. same

Since the connection between the neighboring plates 1a, 1b, 1c is relatively strong, there is no need for special upper or lower plates in a heat exchanger formed by the heat exchanger plate 1 described. This means that all the heat exchanger plates 1 can have the same shape and thickness. The structured three-dimensional pattern may have a shape different from that shown in Figure 1. For example, the pattern may be a spike pattern as is known in the art.

Figure 5 illustrates a version according to the invention of how the tongues 10 can be molded. In this case, a star 17 is cut out of the through opening 5 forming five tongues 10, each having a triangular shape. However, any other form imaginable in the present invention could also be used, such as more rounded tongues.

Having a system with tongues 10 folded down poses a problem in a final plate, for example, a lower plate 18, where there is no neighboring plate.

Figure 6 shows a first solution to this problem, where the bottom plate 18 has a bulge 19 adapted to receive the bent down tongues 10 of a heat exchanger plate 1d contiguous with the end plate 18. It can be seen that the bulge 19 has a depth that is greater than a height of the tongues 10 perpendicular to the plane of the heat exchanger plate 1d contiguous with the end plate 18. In this case it is possible for the tongues 10 to be fully introduced into the bulge 19 without need of deforming tongues 10.

The bulge 19 not only receives the tongues 10 from the heat exchanger plate 1d adjacent to the end plate 18, but also the tongues of the second heat exchanger plate 1e counted from the end plate 18. The tongues of these two plates of heat exchanger 1d, 1e can be connected to the inner wall of the bulge 19. However, it is possible to introduce even more tongues into the bulge 19, ie the tongues of more heat exchanger plates 1d, 1e, .. .

In Figure 7 another possibility is shown. In this case, an end plate 20 having a flat internal surface 21 is used. The tongues 10 of the heat exchanger plates 1d, 1e adjacent to the end plate 20 are further folded which forms the sections 22 running parallel to each other. the inner surface 21 of said end plate 20. These tongues form a layered structure on the inner surface 21 of said end plate 20.

It can be said that the tongues 10 are formed by cutting in one direction with a vector having a component in the radial direction towards the center of the respective aperture 5-8 which is nonzero. The angular component of the vector, being this tangential to the circumference of the aperture, may be zero or nonzero.

Forming the tongues 10 and connecting them as described offers shapes, so to speak, of a tubular structure extending through the depth of the heat exchanger. This provides a sturdy structure in the areas of the openings 5-8. If, instead, the openings 5-8 were flanged in a manner where the periphery of the openings 5-8 was bent down without cutting, with a component of the vector in the radial direction other than zero, the tube formed would also create an airtight seal for fluid access to the spaces between the heat exchanger plates, therefore, the openings would have to be formed. By forming the tongues 10 with a radial component of the vector in the cuts, material will be removed from the opening, as also illustrated in Figure 5 (Figure 3 shows the situation where the angular component of the vector is zero), and then These openings will naturally be formed when the folded tongues 10 are connected downwards, where their sizes will depend on the relationship between the radial component of the vector and the angular component of the vector.

Claims (7)

A heat exchanger comprising a plurality of pairs of heat exchanger plates (1), formed of sheet metal, having a three-dimensional structured pattern (2, 3), a first flow path that is defined within the plurality of said pairs and a second flow path that is defined between said pairs, where each plate (1) has at least one through opening (5-8), where said through opening (5-8) is surrounded by tongues ( 10, 12, 13) cut from the area of the through opening (5-8) and bent outwards, where the tongues (10, 12, 13) of a plate (1) are inserted in the through opening of a plate (1b). ) neighbor, where said languages of a plate (1a, 1b) are connected to the languages (12, 13) of a neighboring plate (1b, 1c), characterized in that the tongues (10) are cut with a radial component of the vector different from zero to have a triangular shape, where said languages (10, 12, 13) have a length, being said length at least twice a distance (16) between neighboring plates (1a, 1b). The heat exchanger according to claim 1, characterized in that the neighboring plates (10, 12; 12, 13) of plates (1a, 1b; 1b, 1c) form connection areas (14, 15), where the adjacent connection areas (14, 15) are separated from each other. The heat exchanger according to any of claims 1 or 2, characterized in that said tongues (10, 12, 13) of neighboring plates have the same angular position with respect to said through opening (5 8). 4. The heat exchanger according to any of claims 1 to 3, characterized in that a final plate (18) is provided with a bulge (19) adapted to receive the tongues (10) of at least one exchanger plate of heat (1d) contiguous with said final plate (18). The heat exchanger according to claim 4, characterized in that said bulge (19) has a depth, said depth being greater than a height of said tongues (10) perpendicular to said adjacent heat exchanger plate (1d) to said final plate (18). The heat exchanger according to any of claims 1 to 3, characterized in that the tongues (10) of a heat exchanger plate (1d), adjacent to a final plate (20), are folded, at least at its end, parallel to said final plate (20). 7. A method for manufacturing a heat exchanger by forming a stack of a plurality of pairs of heat exchanger plates (1), formed of sheet metal, having a three-dimensional structured pattern (2, 3), a first flow path which is defined within the plurality of said pairs and a second flow path that is defined between said pairs, wherein each plate (1) has at least one through opening (5-8), where that through opening (5-8) mentioned is formed by cutting the metal sheet in the area of the through opening (5-8) to form the tongues (10, 12, 13) and bending out said tongues (10, 12, 13), where in a later step the tongues (10) are bent out of the plane of each heat exchanger plate (1a, 1b, 1c), so that the tongues (10) are disposed almost perpendicular to the plane (11) of the heat exchanger plate, and where the tongues (10, 12) of a plate (1a, 1b) are inserted in the through opening e a neighboring plate (1b, 1c), and where the tongues (10, 12) of a plate (1a, 1b) are connected to the languages (12, 13) of the neighboring plate (1b, 1c), and characterized by that the tongues are cut with a radial component of the nonzero vector to have a triangular shape, and where said tongues (10, 12, 13) have a length, said length being at least double a distance (16) between plates (1a, 1b) neighbors.