CN213021136U - Spiral plate heat exchanger - Google Patents

Abstract

A spiral plate heat exchanger comprises a shell, spiral plates (1), a cover plate (2), a flange (3) and a gasket (4), wherein the spiral plates (1) are provided with two spiral channels (10) which are used for heat exchange media to flow along the spiral channels in the shell in a rolling mode along the circumferential direction, and each spiral channel (10) extends along the axial direction of the shell; the gasket (4) comprises a first gasket (41) and a second gasket (42), and the first gasket (41) is arranged between the inner end face of the cover plate (2) and the axial end face of the spiral plate (1) and is in sealing fit with the axial end face of the spiral plate (1); the second gasket (42) is arranged on the periphery of the first gasket (41) along the circumferential direction, and the second gasket (42) is positioned between the sealing surface of the flange (3) and the inner end surface of the cover plate (2) and is in sealing fit with the sealing surface of the flange (3). Compared with the prior art, the cover plate can simultaneously guarantee the pre-tightening amount of the edge and the center of the cover plate, and then the sealing performance is improved.

Description

Spiral plate heat exchanger

Technical Field

The utility model belongs to the technical field of heat transfer device, concretely relates to spiral plate heat exchanger.

Background

The spiral plate heat exchanger is a high-efficiency heat exchange equipment suitable for heat transfer of steam-steam, steam-liquid and liquid-liquid, and its heat exchange surface is formed from two spiral plates which are rolled up so as to form two uniform spiral channels. According to the difference of the end face sealing mode, the spiral plate heat exchanger can be divided into a type I (non-detachable type), a type II (semi-detachable type, namely one channel can be detached and cleaned) and a type III (detachable type), wherein the application of the type I, the type II and the type III is the most extensive.

The structure of the detachable spiral plate heat exchanger is shown in fig. 1 and 2, and comprises a cylindrical shell, spiral plates 1 'arranged in the shell, cover plates 2' arranged at two ends of the shell, flanges 3 'arranged on the peripheral walls at two ends of the shell, and a gasket 4' arranged between the cover plates 2 'and the spiral plates 1', wherein the spiral plates 1 'are provided with two spiral channels 10' which are used for heat exchange media to flow along the spiral channels, and the inner cavity walls of the two spiral plates 1 'are connected through a middle partition plate 11' so as to separate the two spiral channels 10 ', one of the spiral channels 10' is connected with an A fluid inlet connecting pipe 12 'and an A fluid outlet connecting pipe 13' which are used for heat exchange media A to enter and exit, the A fluid inlet connecting pipe 12 'is arranged on the shell, and the A fluid outlet connecting pipe 13' is arranged on the cover plate; the other spiral channel 10 ' is connected with a fluid B inlet connecting pipe 14 ' for the heat exchange medium B to enter and exit, a fluid B outlet connecting pipe 15 ', the fluid B inlet connecting pipe 14 ' is arranged on the cover plate, and the fluid B outlet connecting pipe 15 ' is arranged on the shell (the inlet and the outlet on the same side can be interchanged according to requirements), so that the heat exchange media in each spiral channel are not interfered with each other, and heat exchange is carried out only through the heat transfer performance of the spiral plate; apron 2 ' and the flange 3 ' on the casing pass through connecting piece 5 ' detachable connections, and gasket 4 ' is a monoblock seal structure, and it sets up between apron 2 ' and spiral plate 1 ' and the outer fringe of gasket 4 ' compresses tightly between flange 3 ' and apron 2 ' in order to realize sealed, and this seal structure needs to satisfy the requirement in two respects: firstly, the medium in the spiral plate heat exchanger is prevented from leaking to the outside; and secondly, short circuit (namely leakage between internal heat exchange media) does not occur between the heat exchange media A and the heat exchange media B. Thus, the sealing range extends from near the center of the heat exchanger up to the flange edge.

Because the sealing structure of the flange and the gasket can only be pre-tightened on the outer edge of the cover plate by connecting pieces such as bolts and the like, the pre-tightening amount is quickly attenuated from the edge of the cover plate to the center, if a common gasket is adopted, even if the pre-tightening amount at the edge reaches the upper limit, the pre-tightening amount near the center is often in an insufficient state, if the pre-tightening amount is increased again, the edge of the gasket is over-pressed, and the pre-tightening amount at the center is still not increased much. More seriously, after the heat exchanger is put into operation, under the action of medium pressure, the flange and the cover plate are subjected to buckling deformation, the closer to the center, the more obvious the arching is, the compression amount near the center is rapidly reduced, the tightening force disappears, even a gap appears, and the structure completely loses the function of preventing internal leakage. The above drawbacks are even more pronounced when the spiral plate heat exchanger is at a higher pressure, temperature, or has an especially large diameter. Conventional gasket constructions generally fail to provide a satisfactory seal.

In order to overcome the defects, the prior art mainly reduces the deformation of the cover plate in the pre-tightening stage and the operation stage by increasing the rigidity of the cover plate, so as to reduce the uneven degree of the pre-tightening quantity of the gasket, and the main method is as follows:

firstly, increasing the thickness of a cover plate;

secondly, a cover plate 2' adopting an inverted cone shape (see the detailed figures 5 and 6);

thirdly, an oval cover plate 2' (see the detailed figures 7 and 8) is adopted;

fourthly, reinforcing ribs 21 'are additionally arranged on the back surface of the cover plate 2' (see figures 3 and 4 in detail).

The above method has the following disadvantages:

1) the weight of the cover plate can be increased to a certain extent, so that the material consumption is increased, and the hoisting difficulty is increased;

2) the axial size of the cover plate is increased, which is not beneficial to the arrangement of components such as inlet and outlet connecting pipes of the heat exchanger and is also not beneficial to installation and maintenance;

3) the problem of uneven tightening amount cannot be completely eliminated, but the degree is reduced, particularly in the fourth method, the rigidity is not obviously increased due to the small polar distance of the reinforcing ribs, and the reinforcing ribs can only be used in low-pressure and small-diameter occasions;

4) in order to achieve the sealing purpose, a large pre-tightening force is required, and the pre-tightening force is finally borne by the spiral plate, and the spiral plate is usually of a thin-wall structure and is easy to cause instability damage under a pressure condition.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a first technical problem that will solve is to prior art's current situation, provides one kind and can guarantee simultaneously that apron edge all has the spiral plate heat exchanger of suitable pretension volume with the center to improve sealing performance.

The utility model aims to solve the second technical problem that a spiral plate heat exchanger that also can guarantee sealing performance under the apron receives medium pressure deformation and the heat altered shape condition is provided.

The utility model provides a technical scheme that above-mentioned first technical problem adopted does: a spiral plate heat exchanger comprises a cylindrical shell, spiral plates arranged in the shell, cover plates arranged at two ends of the shell, flanges arranged on the outer peripheral walls of two ends of the shell and gaskets, wherein the cover plates and the flanges are detachably connected through connecting pieces;

the spiral plate heat exchanger is characterized in that the gasket comprises a first gasket and a second gasket, wherein the first gasket is arranged between the inner end surface of the cover plate and the axial end surface of the spiral plate and is in sealing fit with the axial end surface of the spiral plate so as to seal the spiral channels, and further prevent heat exchange media in the two spiral channels from leaking mutually; the second gasket is arranged on the periphery of the first gasket along the circumferential direction, is positioned between the sealing surface of the flange and the inner end surface of the cover plate and is in sealing fit with the sealing surface of the flange to prevent the heat exchange medium from leaking out of the shell, and the pretightening force required by the second gasket is usually larger than that required by the first gasket.

The inner end face of the cover plate is preferably of a planar structure.

When the diameter of the heat exchanger is large, the medium pressure is high, or the temperature is high, the cover plate is easy to deform, so to further solve the second technical problem, preferably, the inner end surface of the cover plate is preferably a convex curved surface structure or a convex conical surface structure, and the convex inner end surface deforms to be a substantially planar structure after the cover plate is deformed by pressure. The cover plate is elastically deformed after being pressed, the inner end face of the deformed cover plate is basically in a plane state, the pressing amount from the center to the outer edge is basically kept consistent during operation, and the pressing amount near the center can be slightly higher or lower than that of the outer edge if necessary, so that reliable sealing is realized. And the structure of apron has light in weight, advantage that axial dimensions is little in this application compare in prior art, and then is convenient for arrange and hoist and mount, the maintenance of heat exchanger component. Meanwhile, under the condition that the cover plate is not deformed, although the inner end face of the cover plate is of a convex structure, the convex amplitude is small, and under the action of the outer edge pre-tightening force, the inner end face of the cover plate is basically of a plane structure, so that the use is not influenced.

Furthermore, the first gasket is wholly circular, the second gasket is wholly circular, and the inner diameter of the second gasket is 0-2 mm larger than the outer diameter of the first gasket.

Further, the axial end face of the spiral plate and the sealing face of the flange are on the same plane.

In the above scheme, a first through hole for the fluid connecting pipe to penetrate through is arranged in the middle of the cover plate, and a second through hole opposite to the first through hole is arranged on the first gasket; the end sealing plate is arranged on the inner side of the first gasket corresponding to the second through hole, and the outer end face of the end sealing plate is in sealing fit with the first gasket. Thereby preventing the heat exchange medium from leaking out of the housing.

Further, the axial end face of the spiral plate, the sealing face of the flange and the outer end face of the end sealing plate are on the same plane.

Further, the first gasket and the second gasket may adopt different thicknesses according to calculation, and of course, the thicknesses of the first gasket and the second gasket may be the same, and the first gasket and the second gasket are designed according to actual working conditions.

Preferably, the connecting piece comprises a pre-tightening bolt and a pre-tightening nut, a connecting hole is formed in the cover plate, and one end of the pre-tightening bolt penetrates through the connecting hole and a hole in the flange and then is connected with the pre-tightening nut.

Preferably, the contact parts of the pre-tightening bolt and the pre-tightening nut with the cover plate and the flange are also provided with a flat gasket and a spring gasket.

And finally, the pre-tightening force required by the second gasket is 2: 1-3: 1. The second gasket may be a metal corrugated composite gasket and the first gasket may be a non-metal gasket. Therefore, when the connecting piece between the cover plate and the flange is pre-tightened, although the tightening force is gradually attenuated from the outer edge to the center, the pre-tightening amount of the first gasket and the second gasket is relatively close because the pre-tightening force required by the first gasket is smaller than that of the second gasket.

Compared with the prior art, the utility model has the advantages of: the gasket is designed into a structure of a first gasket and a second gasket which are distributed inside and outside, and the pretightening force required by the second gasket is larger than the pretightening force required by the first gasket, so that the sealing effect is ensured, the phenomenon of nonuniform pretightening amount when one gasket is adopted in the prior art can be eliminated, and even the pretightening amount at the center of the cover plate can be higher than the pretightening amount at the edge when necessary, so that the effect that the pressing amount at each part of the cover plate is consistent or the center is slightly higher when the heat exchanger operates under the action of certain medium pressure is realized; and this application adopts less pretightning force can reach required sealed effect to can reduce the quantity, the size of connecting piece on the flange, and reduce the risk of spiral plate unstability.

Drawings

FIG. 1 is a schematic structural diagram of a prior art spiral plate heat exchanger;

FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1;

FIG. 3 is a schematic structural diagram of a cover plate with reinforcing ribs according to the prior art;

FIG. 4 is a cross-sectional view taken along line B-B of FIG. 3;

FIG. 5 is a schematic structural diagram of an inverted conical cover plate in the prior art;

FIG. 6 is a cross-sectional view taken along line C-C of FIG. 5;

FIG. 7 is a schematic diagram of an elliptical cover plate according to the prior art;

FIG. 8 is a cross-sectional view taken along line D-D of FIG. 7;

fig. 9 is a partial structural schematic diagram of an embodiment of the present invention;

FIG. 10 is a schematic view of one of the structures of the cover plate according to the embodiment of the present invention;

fig. 11 is a schematic view of another structure of the cover plate according to the embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the following embodiments.

As shown in fig. 9 to 11, for a preferred embodiment of the spiral plate heat exchanger of the present invention, the spiral plate heat exchanger includes a cylindrical casing (not shown in the drawings, the specific structure is the same as that of the prior art), a spiral plate 1 disposed in the casing, cover plates 2 disposed at both ends of the casing, flanges 3 disposed on the outer peripheral walls of both ends of the casing, and a gasket 4.

The cover plate 2 is detachably connected with the flange 3 through a connecting piece 5, the connecting piece 5 is a pre-tightening bolt 51 and a pre-tightening nut 52, a plurality of connecting holes 20 are formed in the outer edge of the cover plate 2 at intervals along the circumferential direction, and one end of the pre-tightening bolt 51 penetrates through the connecting holes 20 and the holes in the flange 3 and then is connected with the pre-tightening nut 52; and flat gaskets and spring gaskets are arranged at the contact parts of the pre-tightening bolt 51 and the pre-tightening nut 52 with the cover plate 2 and the flange 3.

The above spiral plate 1 can be arranged by referring to the existing spiral plate structure, the spiral plate 1 has two spiral channels 10 for the heat exchange medium to flow along, and is rolled along the circumferential direction in the shell, and each spiral channel 10 extends along the axial direction of the shell. And each spiral channel 10 is connected with a fluid connecting pipe for the heat exchange medium to enter and exit, and the fluid connecting pipe can be arranged on the shell and/or the cover plate, which can refer to the prior art.

The gasket 4 comprises a first gasket 41 and a second gasket 42, the first gasket 41 is circular as a whole, is arranged between the inner end surface 22 of the cover plate 2 and the axial end surface of the spiral plate 1, and is in sealing fit with the axial end surface of the spiral plate 1 to seal the spiral channel 10, so that the heat exchange media in the two spiral channels 10 are prevented from leaking each other; the second gasket 42 is integrally annular, and is disposed on the periphery of the first gasket 41, the outer side wall of the first gasket 41 abuts against the inner side wall of the second side wall 42 (that is, the inner diameter of the second gasket 42 is equal to the outer diameter of the first gasket 41, although the inner diameter of the second gasket 42 may also be larger than the outer diameter of the first gasket 41, but the difference is not more than 2mm at most), the second gasket 42 is disposed on the inner side of the flange 3, and is located between the sealing surface of the flange 3 and the inner end surface 22 of the cover plate 2, and is in sealing fit with the sealing surface of the flange 3, so as to prevent the heat exchange medium from leaking out of the casing. In this embodiment, in order to ensure that the first gasket and the second gasket can perform a better sealing effect, the pre-tightening force required by the second gasket 42 is greater than the pre-tightening force required by the first gasket 41, specifically, the pre-tightening force required by the second gasket 42 is 2:1 to 3:1, the first gasket 41 is a metal corrugated tooth composite gasket, and the second gasket 42 is a non-metal gasket, so that when the connecting member 5 between the cover plate 2 and the flange 3 is pre-tightened, although the pre-tightening force gradually attenuates from the outer edge to the center, the pre-tightening amount of the first gasket and the second gasket is relatively close because the pre-tightening force required by the first gasket 41 is less than that of the second gasket 42.

As shown in fig. 9, the inner end surface 22 of the cover plate 2 in this embodiment is a planar structure, and may also be a convex curved surface structure (as shown in fig. 10) or a convex conical surface structure (as shown in fig. 11), where the convex inner end surface 22 deforms to be a substantially planar structure after the cover plate 2 is compressed and deformed, so as to be suitable for a working condition of a heat exchanger with a larger diameter or a higher medium pressure, and during actual production, a deformation condition that may occur after the cover plate 2 is compressed may be calculated first, then a curve of the inner end surface 22 of the cover plate 2 is designed according to a requirement of a tightening force, and then the curve is processed into a curved surface structure of the inner end surface, and when the requirement is not high, the curved surface.

In this embodiment, the middle of the cover plate 2 is provided with a fluid connection pipe 14 for communicating with the spiral channel 10, the middle of the cover plate 2 is provided with a first through hole 23 for the fluid connection pipe 14 to penetrate, the first gasket 41 is provided with a second through hole 410 opposite to the first through hole 23, and the fluid connection pipe 14 passes through the first through hole 23 and the second through hole 410 and then is communicated with the spiral channel 10; in order to ensure the sealing performance, the heat exchanger further comprises an end sealing plate 6, the end sealing plate 6 is arranged on the inner side of the first gasket 41 corresponding to the second through hole 410, and the outer end surface of the end sealing plate 6 is in sealing fit with the first gasket 41 to prevent the heat exchange medium from leaking out of the shell. In this embodiment, the axial end face of the spiral plate 1, the sealing face of the flange 3 and the outer end face of the end sealing plate 6 are on the same plane.

Claims (10)

1. A spiral plate heat exchanger comprises a cylindrical shell, spiral plates (1) arranged in the shell, cover plates (2) arranged at two ends of the shell, flanges (3) arranged on the peripheral walls of the two ends of the shell and gaskets (4), wherein the cover plates (2) and the flanges (3) are detachably connected through connecting pieces (5), the spiral plates (1) are provided with two spiral channels (10) which are circumferentially coiled in the shell and used for heat exchange media to flow along the spiral channels, and each spiral channel (10) axially extends along the shell;

the spiral heat exchanger is characterized in that the gasket (4) comprises a first gasket (41) and a second gasket (42), wherein the first gasket (41) is arranged between the inner end surface (22) of the cover plate (2) and the axial end surface of the spiral plate (1) and is in sealing fit with the axial end surface of the spiral plate (1) to seal the spiral channels (10), so that heat exchange media in the two spiral channels (10) are prevented from leaking mutually; the second gasket (42) is arranged on the periphery of the first gasket (41) along the circumferential direction, the second gasket (42) is located between the sealing surface of the flange (3) and the inner end surface (22) of the cover plate (2) and is in sealing fit with the sealing surface of the flange (3) to prevent the heat exchange medium from leaking out of the shell, and the pretightening force required by the second gasket (42) is larger than that required by the first gasket (41).

2. A spiral plate heat exchanger according to claim 1, wherein: the inner end surface (22) of the cover plate (2) is of a plane structure.

3. A spiral plate heat exchanger according to claim 1, wherein: the inner end surface (22) of the cover plate (2) is of a convex curved surface structure or a convex conical surface structure, and the convex inner end surface (22) deforms to be of a plane structure after the cover plate (2) is pressed and deformed.

4. A spiral plate heat exchanger according to claim 1, wherein: the first gasket (41) is integrally circular, the second gasket (42) is integrally circular, and the inner diameter of the second gasket (42) is 0-2 mm larger than the outer diameter of the first gasket (41).

5. A spiral plate heat exchanger according to claim 1, wherein: the axial end face of the spiral plate (1) and the sealing surface of the flange (3) are on the same plane.

6. A spiral plate heat exchanger according to claim 1, wherein: a first through hole (23) for a fluid connecting pipe (14) to penetrate through is formed in the middle of the cover plate (2), and a second through hole (410) opposite to the first through hole (23) is formed in the first gasket (41); the sealing structure further comprises an end sealing plate (6), the end sealing plate (6) is arranged on the inner side of the first gasket (41) corresponding to the second through hole (410), and the outer end face of the end sealing plate (6) is in sealing fit with the first gasket (41).

7. A spiral plate heat exchanger according to claim 6, wherein: the axial end face of the spiral plate (1), the sealing face of the flange (3) and the outer end face of the end sealing plate (6) are on the same plane.

8. A spiral plate heat exchanger according to claim 1, wherein: the connecting piece (5) comprises a pre-tightening bolt (51) and a pre-tightening nut (52), a connecting hole (20) is formed in the cover plate (2), and one end of the pre-tightening bolt (51) penetrates through the connecting hole (20) and a hole in the flange (3) and then is connected with the pre-tightening nut (52).

9. A spiral plate heat exchanger according to claim 8, wherein: and flat gaskets and spring gaskets are arranged at the contact parts of the pre-tightening bolt (51) and the pre-tightening nut (52) with the cover plate (2) and the flange (3).

10. A spiral plate heat exchanger according to any one of claims 1 to 9, wherein: the pre-tightening force required by the second gasket (42) is 2: 1-3: 1, namely the pre-tightening force required by the first gasket (41).

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