DE2630808A1 - HEAT EXCHANGER - Google Patents

Description

Addition to the main patent. ·. «· (P 24-04-630.8 of January 31

197 *)

Heat exchanger

The invention relates to heat exchangers, i.e. the Apparatus consisting of two liquid or gaseous flow media with different temperatures and possibly different States are flowed through, which are generally in countercurrent in two flow circuits isolated from one another flow to bring their temperatures closer to each other and / or to change the state of at least one of them, whereby the he- inventive improvements one development of the main patent to improve the effectiveness of their heat exchange ^ and to reduce their weight and space requirements »"

According to the main patent, there is such a heat exchanger consisting essentially of a stack of identical circular trays with continuous, from the bottom one each shell outgoing bent edge strips, which are axially placed against one another so that the shells one inside the other intervene and form chambers between them, each shell has two circular holes in the cahe of its circumference, the centers of which lie on two mutually perpendicular radii of the shell, these center points both being the same Distance from the center of the tray, with adjacent trays of the stack each by. 90 against each other are twisted, with the two holes of each shell

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have different diameters and each connected to a collar which are on the two opposite sides of the Protrude from the bottom, the difference between the diameters of these two frets is so dimensioned that the small fret of each bowl is practically in contact with the large one The collar of the guard shell of the stack fits whichever one faces it and is arranged on the same side as the small collar

It is useful that such exchangers can be assembled quickly and easily and also easily disassembled to enable cleaning and, if necessary, repair.

It is also useful to slightly puncture the number of bowls the size of the heat exchange required to be able to modulate.

After all, every shell must withstand thermal stresses without the risk of damaging deformations or cracks or breaks of the metal can withstand.

The invention aims, in particular, for exchangers of this type to train so that they have these different parts of the gate better than before.

The exchangers according to the invention are essentially characterized in that they have an elastic one in each chamber Seal with a arranged along the inner periphery of this chamber first ring and a second ring, the diameter of which is smaller than that of the first ring, which the encircling the large collar passing through this chamber in contact, these two rings being practically tangential in connect the zone of the first ring closest to the large collar to one another, with tightening means being provided, which hold the trays in mutual engagement and any seal between the bottoms of the two enclosing trays flatten slightly.

Preferred embodiments also have one and / or the other of the following features »

- The two rings of each seal are tightly connected to each other and form a single piece;

the flattening of each seal is limited by mechanical stops belonging to the shells;

- the change in the thickness of the seals between

the compressed η state and the uncompressed state "is about 20 % \

- The surface facing the inside of the ring has a double bevel so that its Cross-section has the shape of a V, the tip of which faces the interior of the ring;

the tightening means comprise threaded bolts located outside the shell stack;

- the threaded bolts cooperate with end plates, which are located on the trays at each end of the stack prop up;

- The shells are in such a position that their bent-over edge strips are directed downwards, on the one hand in each of the two annular contact surfaces of every second ring of a seal, which when assembling the Exchanger to come into contact with the opposite shell bottoms, a circular intermediate channel, which suitably has a V-shaped cross-section, and on the other hand in the outside of the tangential connecting zone of the two Rings of the seal lying section a radial incision is provided which extends to the two grooves, so that he connects this with the space outside the seal

The invention is described below with reference to FIG the drawing explained by way of example.

Fig. 1 is a partially taken along line I-I of FIG Fig. 2 sectional side view of a heater according to the invention exchanger.

FIG. 2 is a top plan view of the exchanger of FIG

Fig. 1.

3 shows a shell belonging to the exchanger seen from above.

Fig. 4 shows a plan view according to an improved Embodiment modification of the invention formed exchanger seal .

FIG. 5 is an enlarged partial axial section view of one equipped with the seal of FIG. 4 Exchanger.

809884 / Ö88S

As in the main patent, its different from the connection between the shells and the stacking of these shells Features are applicable here, the exchanger comprises a stack of shells 1, which are made of a highly thermally conductive Metal, e.g. copper, consist and one bottom 2 and one bent over Have edge strip 3

This bent-over edge strip 3 is slightly widened and step-shaped, so that an inner circular shoulder 4 · is created, which acts as a seat for the circular outer rib 6 can serve, which forms the base of the bent edge strip, which engages the bottom of the shell under consideration Bowl connects.

Each bottom 2 is locally deformed so that ribs or other elevations 8 arise.

The purpose of these surveys is twofold:

- by striking the bottom of the neighboring shell, they maintain a smallest, non-zero distance £ between the two opposite bottoms of the bowls upright, so that a chamber 9 is formed between them;

- by creating a partial obstacle to the circulation of water (or other fluid) in this chamber 9 they give the water a certain whirling motion, which the contact between the water and each other opposite bottoms of two trays improved, reducing the heat exchange between those on the two sides a volume of water flowing to each soil is improved.

In the preferred embodiment shown, the elevations 8 are burdened by four parallel ribs, which on the bottom 2 on the same side as the edge strip 3 protrude, and the unit length of which is practically equal to the radius of the shell, the entirety of these four lying next to each other in the middle zone of the bottom 2 Ribs in cross section has a sinusoidal profile, as can be clearly seen in FIG.

In addition, each base 2 contains two circular holes 10 and 11 which are on two mutually perpendicular radii of the bottom 2, both holes being the same Away from the center of the floor.

The hole 10 with a smaller diameter is at one

609884 / 088S

NEN on the side of the bottom 2 opposite the edge strip 3 projecting circular collar 12 connected.

The hole 11 has a slightly larger diameter than the hole 10 and is connected to a circular collar 13, which protrudes on the other side of the bottom 2, i.e. on the same side as the edge strip 3.

The diameters of the "two collars 12 and 13 are like this dimensioned so that the first fits into the second while touching

Such an intervention takes place during the stacking of zv / ei identical shells, which were previously turned by 90 ° against each other were rotated so that axially two collars of these two shell η facing each other, which protrude on the facing sides of these shells

In the embodiments described in the main patent, the mutual engagement of the various shells along the surfaces engaging in contact with one another by heating previously applied brazing beads sealed, ζ · Β · through passage of the entire stack of shells through an oven

Such a design is often advantageous, but has the disadvantage that the exchanger can no longer be separated can be taken ζ · Β · when cleaning or repair is required.

In certain cases it is also useful to use the heat exchange surface of an exchanger that is already in operation to be able to change, ζ · Β. the speed of the To increase heat exchanges or the flow rate of the circulating Change fluids without changing their inlet and outlet temperatures.

Finally, the rigid connection of the shells with brazing beads impairs the free development of thermal stresses, which of the temperature differences of the originate from both fluids between which the heat exchange takes place, and it also makes the manufacture of the exchanger rather complicated and therefore proportionate

expensive·

The type of assembly according to the invention enables

elegant solution to all of these problems.

In each shell 1 there is an elastic seal.

S09884 / Ö88I

orderly. This seal consists of a first ring 31, the Outside diameter equal to the inside diameter of a skirting board 3 of the shell along which it is arranged and a second ring surrounding the collar 13 of the same shell

Although the rings 31 and 32 can be separate, we will the gasket 30 is preferably made in a single piece with the rings 31 and 32 attached to one another in the zone are, which between the federal government 13 and this on The next lying section of the edge strip 3 lies, the two rings in this zone in one another tangential to one another lie.

The thickness of the seal before the trays are stacked is slightly greater in the direction of the stack than that between the smallest distance e_ provided for the opposing bottoms of two shells.

After inserting the seals 30 into the shell 1 and inserting the shells into one another, the stack obtained completed at each end by an end plate 33 »34, which can have the triangular shape shown in Pig · 2 ·

These plates have eyelets 35 »36, which if necessary are provided with internal threads and protrude radially over the shell stack.

In the case of Fig. 1, the eyelets 35 are the upper ones Plate 33 provided with an internal thread, while the eyelets 36 of the lower plate 34 are smooth and have a slightly larger diameter to have.

Threaded bolts 37 are inserted into the holes 36 and one end is screwed into the holes 35. On the plate 34 protruding ends nuts 38 are screwed up.

Thanks to these tightening means, the stack of trays is compressed until the ribs 8 of the bottom of each tray hit the bottom of the opposite shell, as stated above, so that chambers 9 with the height e_ arise.

The seals 30, the original thickness of which is slightly greater than e, are therefore made thanks to the presence of the ribs 8 compressed without being crushed. be, and guarantee such an excellent seal against the fluid circulating in the chambers, both along the

S09884 / 08SI

Hand rails 3 as well as along the .bünde 13.

In a preferred embodiment of the invention, the thickness of the seals is chosen so that they are around changes approximately $ 20 between the uncompressed state and the compressed state of the seal.

For example, if the height e_ of the chambers is 5 mm, the gasket is 6 mm thick when not compressed.

So that the seals do not experience deformation when they are compressed, they must be perpendicular to the direction of the stack have a sufficient width of e.g. 6 mm.

But now the 'contact area is reduced

Seals with the bottoms of the adjacent trays the effective Heat exchange area to the same extent.

So that this reduction remains low, the side of each ring of a seal facing the inside of each ring is preferably double beveled} so that a V-shaped cross-section is produced, the tip P of which faces the inside of the relevant ring.

The seals thus retain sufficient rigidity without the effective heat exchange surface being noticeably weakened.

The seals are preferably made of artificial rubber which is resistant to contact with hot water endures well.

E.g. seals made of ethylene-propylene, made of nitrile rubber or silicone.

As in the main patent, the end plates 33, 34 provided with connecting pieces 19, 2υ for connection to the outer flow circuits.

The combined use of the seals 13, the end plates 33, 34 and the threaded bolts 37 enables at the same time and in a simple manner to make the sealing of the chambers 9 and the assembly of the shells, with the possibility consists of a convenient quick disassembly of the exchanger so formed.

In addition, through the use of threaded bolts

609884/0885

zen of various lengths possible, the number of shells the desired Adjust the purpose, even with a heat exchanger that has already worked.

After all, each shell is mechanically different from that

Neighboring shells independently and can freely absorb the thermal stresses that act on their two walls Temperature differences are generated.

The exchangers can be used for any desired heat exchange between two fluids. You can particularly advantageously equip the so-called "mixed" systems for central heating and hot water output, i.e. systems with a single boiler for these two purposes, with the exchanger from the one facing the boiler The warm water exiting the closed central heating circuit and the cold water flowing through it, which should be heated for its output by removal. These exchangers can also be used to form evaporators, condensers or cookers, especially in chillers, heat pumps, etc.

In certain designs, any connection between the two fluid circuits must be prevented. This is the case, for example, if these two flow circuits are a closed central heating circuit or a circuit for extraction are of warm water, as the fluid contained in the first of these two flow circuits can be water, to which an antifreeze agent is added, and which more or less becomes dirty due to its prolonged circulation in radiators is, while that flowing in the second flow circuit Water must remain pure and potable.

Fun is to be feared that over time the seals 30, or more precisely the second rings 32 of the same, lose part of their elasticity and light between them and the bottoms of the bowls pressing on them Let leakage currents of water (or other fluid) pass through. These leakage currents can be undesirable Create connections between the two flow circles at the point of their nested collars, as the mutual Engagement of these frets is not strictly tight in itself.

809884/0885

.. 9 -

An embodiment shown in FIGS. 4 and 5 sabwan dl ung makes it possible to remedy this disadvantage and the automatic removal of any to ensure undesired leakage flows from the exchanger, which can occur at the point of the nested collars.

In this variant embodiment, the bent edge strips 3 of the nested shells are so after directed downwards, that the large collar 13 of each shell is directed downwards and its small collar 12 is directed upwards.

As before, the seal is made at the location of the nested collars by placing the opposing collars Bottoms of the shells are made on two horizontal ring-shaped contact surfaces with a radial thickness of el, which limit the second ring 32 of the seal 30 arranged between these bottoms at the top and bottom.

In the central zone of each of these annular Contact surfaces is a continuous circular groove 39 coaxial with the contact surface Cross-section expediently has the shape of a V.

Furthermore, there is an incision extending radially from the outside 40 mounted in the outer surface of the two rings 31 and 32 common portion.

The radial depth of this incision, which is preferably is of the order of half the thickness of the seal 30 in the relevant zone, it is provided that that they are concerned about the leaky gap 41 between the interlocking edge strips 3 of the two Shells the channels 39 directly with the space outside the seal, i.e. with the atmosphere.

This double measure has the advantage of remedying any sealing defects that may have occurred at the point of the rings 32 could occur.

Any leakage flow of a fluid coming from one of the two flow circuits in the direction on the other must namely flow radially at the inner or outer edge of a channel 39 in the direction of the same and is then caught by the chin, from where it is automatically through the incision 40 and the space 41 in the direction

- ίο -

direction of the arrow F to the outside of the exchanger

It should also be noted that in the two flow circles of the fluid flowing through the exchanger are at pressures above atmospheric pressure, while in atmospheric pressure prevails in the grooves 39. This has the consequence that any above leakage flow upon arrival in a Channel 39 from one of the two flow circles has no tendency to continue its path in the direction of the other flow circle, because in this there is a relative overpressure compared to the channel, so that the leakage flow only from this channel can be discharged.

In this way, an excellent permanent separation between the two is ultimately obtained in a very simple manner Fluid, which in the successive, limited by the nested shells stages of the exchanger flow without the need for welds or brazing between the shells on the In place of their margins or their interlocking frets.

The invention can of course be modified. So is the use of the threaded bolts described above particularly simple and easy to manufacture, but of course other methods can also be used to make the shells to press against each other up to the mutual stop.

809884/0881

Claims (12)

PATENT CLAIMS (JT) Heat exchanger with a stack of identical circular shells with continuous, from the bottom of each shell starting bent edge strips, which are axially placed against one another so that the shells engage and form chambers between them, each shell in the .Nnah their Has two circular holes around the circumference, the centers of which lie on two mutually perpendicular radii of the shells, whereby these centers are both at the same distance from the center of the shell, whereby adjacent shells of the stack are each rotated by 90 ° against each other, the two holes of each Shell have different diameters and are each connected to a collar which protrudes on the two opposite sides of the bottom, the difference between the diameters of these two collars is such that the small collar of each shell is practically in contact with the large collar of the Neighboring shell of the S tapels fits, which faces him and is arranged on the same side as the small collar, according to the main patent .... (P 24 04 630.8 of January 31, 1974), characterized in that it has an elastic in each chamber (9) Seal (3υ) with a first ring (31) arranged along the inner circumference of this chamber and a second ring (32), the diameter of which is smaller than that of the first ring, which comes into contact with the large collar (13) passing through this chamber surrounds, these two rings adjoining each other practically tangentially in the zone of the first ring closest to the large collar, with tightening means (33, 38) being provided which hold the shells in mutual engagement and any seal between the bottoms of the two them Slightly flatten the surrounding shells. 2. Heat exchanger according to claim 1, characterized in that that the two rings (31 »32) of each seal are firmly connected and form a single piece. 3. Heat exchanger according to claim 1 or 2, da- 609884/0881 characterized in that the flattening of each seal (30) is limited by mechanical stops belonging to the shells will. 4. Heat exchanger according to claim 3, characterized in that that the mechanical stops are formed by parallel ribs (8) formed in the bottom (2) of each shell will. 5. Heat exchanger according to one of claims 1 to 4, characterized in that the change in the thickness of the seals (30) between the compressed state and the uncompressed state is about 20 fo. 6. Heat exchanger according to one of claims 1 to 5, characterized in that the inside of the ring facing surface of the same has a double bevel, such that its cross-section has the shape of a V, the tip of which (P) faces the inside of the ring. 7. Heat exchanger according to one of claims 1 to 6, characterized in that the seals (30) are made of artificial rubber. 8. Heat exchanger according to one of claims 1 to 7, characterized in that the tightening means outside of the stack of shells lying threaded bolts (37). 9. Heat exchanger according to claim 8, characterized in that the threaded bolts (37) with the plates (33, 34) cooperate, which are supported on the shells at each end of the stack. 10. Heat exchanger according to one of claims 1 to 9, characterized in that the shells (1) are in such a position that their bent-over edge strips (3) are directed downwards are, on the one hand in each of the two annular contact surfaces of every second ring (32) of a seal (30), which should come into contact with the opposing shell bottoms when the exchanger is assembled, a circular intermediate channel (39) and on the other hand in the outside of the tangential connecting zone of the two rings (31, 32) the section lying on the seal is provided with a radial incision (40) which extends to the two grooves (39), so that he connects this with the space outside of the seal 609884/088 5 contacts. 11. Heat exchanger according to claim 10, characterized characterized in that each channel (39) has a V-shaped cross section. 12. Heat exchanger according to claim 10 or 11, characterized in that the radial incision (40) has a depth which, in terms of size, is half the thickness of the Seal in the zone of formation of this incision. Blank page