JPH11101583A - Leaf-like plate type heat exchanger and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plate type heat exchanger for largely reducing pressure loss with excellent heat conductivity, heat resistance and corrosion resistance without fear of leakage. SOLUTION: Thin heat fusible resin to be heat fused with a thickness of 10 to 100 μm or preferably fluororesin film 10 is directly heat fusion bonded to a heat transfer surface 2 of a heat exchange plate 1. Then, two plates obtained by fusion bonding the films 10 are opposed, and a U-shaped sectional member is fusion bonded to a sealing line of the films 10 to form a flexible bag-like structure. Since the sealing line is connected in the flexible bag-like state, no leakage occurs from a unit A or gasket connecting surface. And, the films each having no pinhole are laminated, and hence aluminum plates, metal plated steel sheets or thinner stainless steel sheets can be used for corrosive fluid with high total heat transfer coefficient. Further, its structure is simplified by providing an inlet 15 and an outlet 15' at the U-shaped sectional members of a leaf-like unit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate-type heat exchanger, and more particularly, to a leaf-type plate heat exchanger in which a plurality of heat exchange plates are arranged in parallel at a predetermined interval from each other and the sealing line is formed in a flexible bag shape. Pertaining to exchangers. Preferably, the present invention relates to a leaf-type plate heat exchanger suitable for a plate constituted by lining at least one surface of a heat transfer surface of a plate with a fluororesin film. More preferably, the heat transfer surface of the plate is lined with a thin fluororesin film, and then the sealing line of the plate is formed in a bag shape, so that heat resistance, corrosion resistance and heat transfer efficiency are good, and there is no pinhole, and the gasket can be used. The present invention relates to a leaf-shaped plate heat exchanger that has no risk of leakage. Another preferred embodiment relates to a leaf-shaped plate heat exchanger in which fluid flows in one direction between the plates.

[0002]

2. Description of the Related Art As shown in FIG. 1, a conventional plate heat exchanger usually has liquid passage holes 4, 5,.
A heat exchanger plate group constituted by arranging the plate-like plates 1 provided with the plates 6 and 7 in parallel at predetermined intervals via a gasket 3 is constituted by a fixed frame 8 and a movable frame 9 shown in FIG.
The gasket 3 to be abutted is compressed and connected by being sandwiched between the two and tightening with a stay bolt and a nut. However, various inventions have been devised as countermeasures to prevent leakage from the portion where the plate 1 abuts and the gasket 3 is compressed.

As shown in FIG. 2, the flow direction of the liquid flowing through the plate type heat exchanger is completely opposite to the flow direction of the flow path C indicated by the solid line arrow and the flow direction of the flow path D indicated by the broken line arrow. 1
Even in the case of the circulation type, there is a disadvantage that the pressure loss is large because the flow path is bent at a right angle. In the figure, reference numeral 4 denotes a liquid passage hole inlet for high-temperature fluid, 5 denotes its outlet, 6 denotes a liquid passage hole inlet for low-temperature fluid, and 7 denotes its outlet. In order to increase the efficiency of the single flow system, when the multiple flow system is used, the fluid is sharply folded back at the liquid passage hole, causing an excessive pressure loss.

Regarding leakage, it has been proposed to attach a gasket to the plate with an adhesive, or to form a unit as a set of two units, and seam weld the periphery of the unit to integrate them. When tightening between the frame and the movable frame, there is a defect that the distortion of the plate and the variation of the shape, thickness, density, etc. of the gasket are accumulated and manifested by stacking a large number of plates, leading to leakage.

As for the pressure loss, Japanese Patent Application Laid-Open No. Sho 60-33490 proposes a plate having a wide contact surface and a pair of continuous helical flow paths. was there. No other proposals have been made for the improvement of the pressure loss, and it has been abandoned as an essential disadvantage of the plate heat exchanger.

[0006] In the plate heat exchanger, a fluid flows along the plate, but the surface of the plate is significantly affected by the fluid. As an example, experts know that widely used stainless steel is vulnerable to seawater. In addition, most plates are corroded by corrosive liquids and gases, contaminated water accumulates dirt on the plate surface, and seawater causes shellfish and seagrass to adhere to them and proliferate endlessly. The heat exchange rate is significantly reduced due to the increase in the thermal resistance. JP-A-61-101797 proposes to coat an enamel on at least the surface of a plate for a corrosive liquid. To prevent foreign matter from adhering
In Japanese Utility Model Laid-Open Publication No. 2-127987, it is proposed to coat an amorphous metal entirely or partially.
Japanese Utility Model Laid-Open Publication No. 7-22269 proposes forming a coating layer mainly composed of a tetrafluoroethylene resin on a plate surface by plating, painting, baking, or the like. In recent years, the thickness of a coating of a polyphenylene sulfide (PPS) -based coating material is 80 to 50.
A lining of 0 μm has been proposed.

When the plate surface is coated with an enamel or a tetrafluoroethylene resin, it is said that pinholes are always generated, so that it is necessary to apply a thick coat, which increases the cost and significantly lowers the heat transfer efficiency. Had become. Therefore, conventionally, there has been a demand for the development of a plate-type heat exchanger that does not leak onto the surface of the plate that comes into contact with the corrosive liquid or seawater, and that has been subjected to a surface treatment with a low-cost heat-resistant and corrosion-resistant resin.

There has been a demand for the development of a plate heat exchanger having a very small pressure loss.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a thin and pinhole-free synthetic resin layer, particularly preferably a fluororesin film, on the surface of a plate forming a liquid passage for a fluid and a heat transfer surface. To form a lining coating,
An object of the present invention is to provide an inexpensive plate heat exchanger that is stable and can withstand long-term use. Yet another object is to provide a plate heat exchanger with extremely low pressure loss.

[0010]

In order to solve the above-mentioned problems, in the present invention, a synthetic resin layer is laminated on a plate, particularly preferably a fluororesin film is laminated by thermocompression bonding. As the fluororesin of the fluororesin film, those which can be melted by heat are desirable, for example, tetrafluoroethylene-perfluoroalkylvinyl ether copolymer (hereinafter, referred to as PFA) and ethylene-tetrafluoroethylene copolymer (hereinafter, referred to as ETFE). ) Can be exemplified. The fluororesin film is thermally bonded at least on the heat transfer surface of the plate, and a sealing line surrounding the heat transfer surfaces of the two fluororesin films facing each other as a unit is formed into a bag shape with a flexible U-shaped cross-sectional member. It is designed to be integrated. Further, by providing an inlet and an outlet in the flexible U-shaped cross section member, the fluid can flow only in one direction on the plate surface, and the pressure loss can be reduced.

[0011]

In the plate type heat exchanger,
A pair of plates on which the fluororesin film is laminated constitutes a unit in which at least the heat transfer surface is completely a bag-like space of the fluororesin film, thereby preventing leakage from the gasket. In addition, there is no liquid passage hole provided at the four corners as in the related art, and an inlet and an outlet are provided in a U-shaped cross-sectional member which is joined to two plates to constitute a unit so that fluid flows only in one direction. It has become. That is, the unit is leaf-shaped, and the shaft (entrance) of the leaf
And diffuses at the leaves (plates), and the fluid converges and flows toward the leaves (outlets). The inlet and outlet of this unit are connected to the high-temperature fluid-side inlet and outlet or the low-temperature fluid-side inlet and outlet, respectively, and are extended and connected by tubes. The tube at this time is not only rigid but also flexible.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to the accompanying drawings. The same components are denoted by the same reference numerals and description thereof will be omitted.

[Embodiment 1] The feature of this embodiment is that a sealing line of a fluororesin film lined on a heat transfer surface facing each other of two plates constituting a unit is integrally joined with a U-shaped cross section member by heat sealing. That is, it is in the shape of a bag. FIG. 3 schematically shows a plate of the leaf-shaped plate heat exchanger of the present invention. The plate 1 is made of stainless steel having a thickness of 0.8 mm, and this surface is sandblasted with a maximum height (Rmax) of 10 to 30 μm, and then chemically etched with a mixed acid of 10% nitric acid and 40% hydrochloric acid at 30 ° C. After the treatment, the stainless steel plate is heated to 330 ° C., and the fluororesin film 10 is directly fused by a roller. The fluororesin film 10 of this embodiment is melted by heat and directly adheres to the entire surface of the plate 1. The fluororesin film 10 has a thickness of 2
It is a 0 μm fluororesin (PFA) film. However,
The melting point of PFA is 310 ° C. Fluororesin (PFA)
A stainless steel plate to which the film is heat-sealed is cut and press-molded into a predetermined shape to obtain a plate 1. At this time, a U-shaped cross-section member 11, a gasket groove, or a flange may be provided as necessary. Further, a corrugated pattern for increasing heat transfer efficiency is formed on the heat transfer surface 2 (note that grooves, flanges, corrugated patterns, etc. are not shown).

As shown in FIG. 3, a fluororesin (P
FA) A U-shaped cross-section member 11 made of the same material as the film 10 is installed such that the body 12 is on the heat transfer surface side.

As shown in FIG. 4A, the U-shaped cross section member 11 has upper and lower parallel portions 13 which are partially heat-sealed to the fluororesin film 10 of the plate 1, and a cylinder shown in FIG. An inlet 15 and an outlet 15 ′ are provided continuously. Then, the partially joined portion 14 of the upper and lower parallel portions 13 is
Is thermally fused to the fluororesin (PFA) film 10 to be integrated. FIG. 4C shows an example in which the gasket 3 is attached to the unit A. Preferably, the inlet 15 and outlet 15 'of the present invention are slightly off center as shown in FIG. Protrusions 16 may be provided on the main parts of the inlet 15 and the outlet 15 'of the present invention so that when the unit A is tightened, the cylinder is crushed in the tightening direction so as not to be closed.

As shown in FIGS. 3 and 4, a portion 14 of the upper and lower parallel portions 13 of the U-shaped cross-sectional member 11 is heat-sealed to the sealing line of the fluororesin (PFA) film 10 of the plate 1, as shown in FIGS. To form a flexible bag. As the structure of the U-shaped cross-sectional member 11, it is preferable that the entire thickness is larger than that of the fluororesin film, and that the body 12 is flexible and can be bent and stretched like a bellows. The flexible body 12 absorbs distortions, twists, misalignments, distortions from thermal expansion and other inconveniences of the plate 1.

In FIG. 3, the cylindrical inlet 15 and outlet 15 'are preferably formed in such a manner that the body 12 of the U-shaped cross section member 11 is deformed and protrudes. The upper and lower parallel portions 13 are continuous with the inlet 15 and the outlet 15 'so that no leak occurs when they are joined. The cylindrical inlet 15 and outlet 15 ′ are separately formed by injection molding, blow molding, or the like, and are formed in a U-shaped cross-section member that is previously formed in a string shape by extrusion molding or the like and cut to a predetermined length. 11 by welding or the like. According to this method, the length of the U-shaped section member 11 can be freely changed, and at the same time, the length, size, etc. of the plate can be changed to freely set the heat transfer coefficient.

A cylindrical entrance 15 and a U-shaped section member 11
It is preferable that a reinforcing material such as a fiber is filled and inserted in a manufacturing process such as injection molding or extrusion molding.

The units A, A prepared as described above are provided with a gasket and installed and clamped between the fixed frame 8 and the movable frame 9 as shown in FIG. 5 to form a leaf-shaped plate heat exchanger. In FIG. 5, a broken line 11 is a U-shaped cross-section member joined to the sealing line. In this example, the prepared unit A is alternately arranged on the high-temperature side and the low-temperature side alternately, and the respective inlets 15, 15... And the outlets 15 ′, 15 ′. Are connected together as inlets 4 and 6 and outlets 5 'and 7' to form a leaf-shaped plate heat exchanger in which the high-temperature side body and the low-temperature side fluid are completely countercurrent.

[0019]

Embodiment 2 This embodiment is characterized in that a U-shaped cross section member 11 'is separately provided between the units A prepared in Embodiment 1 as shown in FIG. . That is, the unit A 'is constituted by utilizing the back surfaces of the plates 1 and 1 of the units A and A and providing a U-shaped cross-sectional member 11' thereon. When the channel A is formed in the unit A, an inlet and an outlet are also provided in the U-shaped cross-sectional member 11 ′, and the unit A ′ is configured to be the channel D. This doubles the heat transfer efficiency of the leaf plate heat exchanger of the present invention. Thus, the metal of the plate 1, for example, a stainless steel plate may be exposed on the back surface of the plate 1 depending on the fluid passing therethrough, or a fluororesin film may be separately laminated as necessary. The fluororesin used here may be the fluororesin (PFA) used in the unit A: melting point 310 ° C., but it is preferable to use a fluororesin (ETFE) film that can be processed at a lower temperature (melting point 270 ° C.). Also, the U-shaped cross section member 11 ′ used is preferably made of fluororesin (ETFE). A synthetic resin film other than the fluororesin film, for example, a film of polyester, polyamide, polypropylene or other heat-meltable synthetic resin, or a paint can be used. Further, a thermoplastic elastomer having both properties of a synthetic resin and a rubber, such as an amide-based thermoplastic elastomer, an olefin-based thermoplastic elastomer, and a styrene-based thermoplastic elastomer, can be used. A coating such as epoxy or PPS may be lined. The U-shaped cross-section member 11 ′ applied at this time is not only the fluororesin but also a synthetic resin material such as polyester or polyamide, silicon rubber, nitrile rubber, butyl rubber used in the gasket 3,
Rubber-based materials such as high-pylon and thermoplastic elastomer-based materials can also be suitably used. Then, it is assembled in the same manner as in Example 1 to obtain a leaf-shaped plate heat exchanger.

[0020]

Embodiment 3 In this embodiment, as shown in FIG. 6 (b), instead of the U-shaped cross-section member 11 'provided between A and A in the second embodiment, the U-shaped cross-section member 11 is used. It is characterized in that a gasket 3 'similar to' is assembled at the same position. The gasket 3 'is also provided with an inlet and an outlet to form a unit A'. When the unit A is the channel C, the unit A ′ can be the channel D. In this example, not only the heat transfer efficiency is doubled, but also the assembly can be performed by fastening the vault and nut, so that the leaf-shaped plate heat exchanger is easy to manufacture.

[0021]

Embodiment 4 In this embodiment, as shown in FIG. 6C, first, one of the upper and lower sides of the parallel portion 13 of the U-shaped cross-section member 11 is joined to each of the plates 1. It is a feature. Then, the plates 1 joining the U-shaped cross-section members are arranged in parallel or stacked, and the remaining parallel portions 13 are joined to the adjacent plate 1 in order. Thus, a plate group in which the units A are continuous is configured. Further, a leaf-shaped plate heat exchanger in which units A and A 'are alternately provided.

[0022]

Embodiment 5 This embodiment is characterized in that the unit A is formed in a gutter-like shape in the longitudinal direction as shown in FIG. The gutter unit 18 is provided with rigidity in the longitudinal direction.

[0023]

Embodiment 6 In this embodiment, the unit A is replaced with the reinforcing unit B.
It is characterized by having. As shown in FIG. 8, a wire net 19 is provided on the side surface of the unit A to individually protect the unit A. Even if the reinforcing unit B is used alone, even if the plate 1 has a thickness of only 0.8 mm due to a pressure difference between the inside and outside of the unit, the plate 1 is not broken by the internal pressure. In this example, the wire mesh 19 is SUS304 and the reference wire diameter is 3.15.
mm, with a standard weave of 12.5 mm, woven in a plain weave, the periphery of which is surrounded by a frame 20 and sewn with a vault nut 21 to provide a rigid structure. ing. In FIG. 8, reference numeral 15 denotes a fluid inlet. Thereby, the unit A is protected in the basket, and at the same time, the fluid flowing outside the unit A is agitated by the wire net 19, so that the heat transfer efficiency can be increased.

[0024]

[Embodiment 7] In this embodiment, as shown in FIG. 9, a plurality of reinforcing units B are arranged in parallel, and a frame 23 is fixed with a vault nut 21 with a member 22 holding a gap in a gap therebetween. It is characterized by one block 24. In the figure, reference numeral 15 denotes an inlet / outlet for the fluid C, and a fluid D flows between the reinforcing units B, B.

[0025]

Embodiment 8 In this embodiment, as shown in FIG. 10, a closed case 25 having a hot fluid side inlet 4 and a hot fluid side outlet 5 is provided.
, The reinforcing unit B or the block 24 is arranged in parallel at a predetermined interval. And the entrance 15 and the exit 15 ′ of this reinforcement unit B are
This is a structure in which a low temperature fluid side inlet 6 and a low temperature fluid side outlet 7 are combined by a tube 17. The low temperature fluid side port and the high temperature fluid side port may be reversed.

[0026]

Embodiment 9 This embodiment is characterized in that the open case 26 is open at least one of the left, right, upper and lower sides as shown in FIG.
Alternatively, the blocks 24 are arranged side by side at predetermined intervals.

In the above description, a U-shaped cross-section member is described as a bag-shaped member for convenience. However, the cross-section member is of course not limited to this, and other cross-sectional shapes such as M Or a shape like Z. At this time, the U-shaped cross-section member may be bonded with an adhesive.
In addition, the method of directly hot-melting and bonding the fluororesin film to the plate has been described above, but the present invention is not limited to this, and may be, for example, bonding with an adhesive. A heat-resistant primer is applied to the surface-treated plate, and after heating the plate, a fluororesin film is directly thermally bonded onto the primer. Alternatively, a fluororesin film coated with a hot melt material on one side may be pressed against a heated plate and thermally bonded. Furthermore,
It can also be bonded with an adhesive. It goes without saying that not only a fluororesin film but also a polyamide, polypropylene or other heat-fusible synthetic resin can be used instead. The thickness, type, number, and the like of these heat-fusible synthetic resins such as fluororesins are not limited to the above examples. Fluororesin film on the plate,
Polyamide, polypropylene or other hot-melt synthetic resin films or paints can be treated on one or both sides. If necessary, a paint such as epoxy or PPS may be applied.
Further, a metal such as a stainless steel plate or a titanium plate may be exposed on the heat transfer surface. The U-shaped section member is preferably made of the same material as the synthetic resin laminated on the plate. However, other thermoplastic elastomers, rubbers and the like may be used. The same applies to the inlet and outlet members. Using a U-shaped cross section member to compose the unit with the plate,
A plate heat exchanger provided with an inlet and an outlet or a plate heat exchanger which is freely focused and piped by extending the inlet and the outlet with a tube or the like is naturally included in the present invention. In the above description, the plate heat exchanger mainly including two plates as one unit has been described. However, the present invention is not limited to this.
All plate heat exchangers that exchange heat by arranging plates in parallel are included. The units configured in a gutter shape are all included regardless of the cross-sectional shape. FIG.
(C) In the example of FIG. 6 (b), the mounting position of the gasket 3 is described at a position deviating from the upper and lower parallel portion 13 of the U-shaped cross-sectional member 11, but the gasket 31 described in FIG. As described above, it is preferable to be provided so as to overlap on the upper and lower parallel portions 13.

[0028]

As described above in detail, according to the present invention, it is possible to use a heat-meltable resin film, particularly a fluororesin film, which is thin but has no risk of pinholes. By providing the and the outlet, various effects listed below can be obtained. (1) Since the lined fluororesin film is formed in a bag shape, there is no possibility of leakage from the connection part of the sealed line. (2) Since the fluororesin film is formed in a bag shape, the plate constituting the unit is distorted due to thermal expansion,
Even if it is displaced, twisted or other inconvenience occurs, it is not destroyed, absorbs its error and does not cause leakage. (3) Since there is no possibility of pinholes in the fluororesin film, aluminum or plated steel plate having good thermal conductivity can be used for the plate, and the apparatus can be reduced in size and inexpensive. (4) In the U-shaped cross section member, by providing the fluid inlet and outlet in the direction of the gap between the units, the fluid flows substantially linearly, and the pressure loss is greatly reduced. (5) Since tubes can be freely connected to the inlet and outlet of the high-temperature fluid side and the low-temperature fluid side with tubes from the inlet and outlet of the unit, the flow direction and the fluid can be distributed for each unit.
In addition, since the flow path can be shut off, the setting and changing of the heat transfer coefficient become easy. (6) Since the U-shaped cross section member is flexible, the interval between the two plates can be freely set or changed, so that the setting and changing of the heat transfer coefficient become easy. (7) Since the flow path does not have a right-angled flow, a curved flow, a bent flow, and the like, the cleaning is facilitated. (8) The outer surface of the plate is protected by a wire mesh, and at the same time, the fluid flowing on the outer surface of the plate is disturbed to increase the heat transfer efficiency. (9) Even if the unit is made gutter-shaped, the unit has strength even if it is long, and can be handled like a single tube. Therefore, a design close to a multi-tube heat exchanger is also possible.

[Brief description of the drawings]

FIG. 1 is a front view showing a plate and a fluid flow of a conventional plate heat exchanger.

FIG. 2 is a side view illustrating the flow of FIG.

FIG. 3 is a partially cutaway perspective view of a leaf-shaped plate according to one embodiment of the present invention.

FIG. 4 is an enlarged sectional view of a main part in which a U-shaped sectional member is joined to the unit. (A) shows an aspect of the upper and lower parallel parts. (B) shows the form of the cylindrical inlet or outlet. (C) shows an embodiment in which a gasket is attached to a U-shaped cross section member.

FIG. 5 is a perspective view of an embodiment in which plates are stacked in parallel.

FIG. 6 is an enlarged sectional view of a main part of an embodiment constituting a plate group. (A) is an assembly in which another U-shaped cross section member is joined between the units A. (B) Assembled with a gasket between units A. (C) arranges the plate which joined the U-shaped cross section member on one side,
A plate group in which the remaining one side is sequentially joined to an adjacent plate.

FIG. 7 is a perspective view showing an embodiment in which a leaf-shaped plate is formed in a gutter shape.

FIG. 8 is an explanatory diagram of the reinforcing unit as viewed from a side.

FIG. 9 is an explanatory diagram of a block of the reinforcing unit as viewed from a side.

FIG. 10 is a plan view showing another embodiment, in which a plate is put in a sealed case and a part of the case is cut away.

FIG. 11 is a perspective view showing still another embodiment, in which a plate is put in a partially open case, and a part of the case is cut away.

[Explanation of symbols]

 A. Unit B. Reinforcement unit C. Channel D. Channel 1. Plate 2. Heat transfer surface 3. Gasket 4. Liquid passage hole 5. Liquid passage hole 6. Liquid passage hole 7. Liquid passage hole 8. Fixed frame 9. Movable frame 10. Fluororesin film 11. U-shaped section member 12. Torso 13. Concurrent part 14. Joint 15. Entrance 15 '. Exit 16. Protrusion 17. Tube 18. Gutter unit 19. Wire mesh 20. Frame 21. Bolts and nuts 22. Member 23. Frame 24. Block 25. Sealed case 26. Open case 31. gasket

Claims (19)

[Claims] 1. A plate type heat exchanger comprising a plurality of plates arranged in parallel at a predetermined interval, wherein at least two plates preferably formed in a symmetrical or similar shape are combined to form one unit. And the combination 2
The U-shaped cross-sectional member provided with the inlet and outlet of fluid is joined to a sealed line surrounding the heat transfer surface inside the two plates facing each other and joined to form a flexible bag. Plate heat exchanger. 2. The method according to claim 1, wherein the two combined plates face each other, and a synthetic resin layer is formed inside the two plates.
The plate according to claim 1, wherein the synthetic resin layer is bonded to the plate at least on a heat transfer surface of the plate, and is joined to a U-shaped cross-section member in a sealing line surrounding the heat transfer surface to form a flexible bag. Type heat exchanger. 3. The synthetic resin layer is obtained by lining a fluororesin film by lamination.
4. The plate heat exchanger according to 1. 4. The plate heat exchanger according to claim 1, wherein the U-shaped cross-section member has a body portion joined to the heat transfer surface side. 5. The plurality of units are juxtaposed at predetermined intervals, and each of the juxtaposed plates is joined by the U-shaped cross-section member, and at the same time, a fluid inlet and an outlet are connected thereto. The leaf-shaped plate heat exchanger according to any one of claims 1 to 4, which is provided. 6. The assembly according to claim 1, wherein said plurality of units are arranged side by side at predetermined intervals, and a gasket provided with an inlet and an outlet for a fluid is interposed between each of the arranged plates. A leaf-shaped plate heat exchanger according to Crab. 7. The U-shaped cross-section member or a material whose inlet and outlet are reinforced with a reinforcing material such as fiber.
The leaf-shaped plate heat exchanger according to claim 4. 8. A leaf-shaped plate heat exchanger according to claim 1, wherein projections are provided on the cylindrical inlet and outlet of the U-shaped cross-section member. 9. The leaf-shaped plate heat exchanger according to claim 1, wherein a predetermined gasket is provided outside the U-shaped cross-section member. 10. The inlet and the outlet of the plurality of parallel units are respectively piped and collected by a tube or the like, and the inlet and the outlet of the plate type heat exchanger on the high temperature fluid side or / and the low temperature fluid side of the plate type heat exchanger. The leaf-shaped plate heat exchanger according to any one of claims 1 to 8, which is connected to an inlet and an outlet. 11. The unit as claimed in claim 1, wherein a reinforcing wire mesh is provided on a side surface of the unit unit.
10. The plate heat exchanger according to any one of 7, 8, and 9. 12. The leaf-shaped plate heat exchanger according to claim 10, wherein said reinforcing units are arranged side by side at intervals and constitute a block of the reinforcing unit. 13. The leaf-type plate heat exchanger according to claim 1, wherein the cross-sectional shape of the unit is formed in a gutter shape such as an arc shape or a bent shape. 14. A leaf according to any one of claims 1 to 12, wherein at least one set of units or reinforcing units is disposed at predetermined intervals in a sealed case provided with a fluid inlet and an outlet. Plate heat exchanger. 15. The leaf-shaped plate according to claim 1, wherein at least one set of units or reinforcing units is disposed at a predetermined interval in a cylindrical case having at least one open side. Type heat exchanger. 16. A unit is formed by providing an inlet and an outlet in advance in the U-shaped cross section member and joining them at predetermined positions of two plates facing each other. A method for manufacturing a leaf-shaped plate heat exchanger according to claim 1. 17. A laminate of a fluororesin film and / or a heat-fusible synthetic resin or a thermoplastic elastomer film with the metal of the plate exposed, or one or both surfaces of the plate, or a polyphenylene sulfide-based film The method for manufacturing a leaf-shaped plate heat exchanger according to claim 2, wherein the U-shaped cross-section member is joined thereon by painting, epoxy-based painting, or the like. 18. A gasket similar to a U-shaped cross-section member is interposed between the plurality of units, and the gasket is fastened with a vault nut to assemble the units. 3. The method for producing a leaf-shaped plate heat exchanger according to 1.). 19. A method in which the metal of the plate is exposed, or a fluororesin film and a heat-fusible synthetic resin film are laminated on one or both surfaces of the plate, or a polyphenylene sulfide coating, an epoxy coating, or the like is applied. Either one of the upper and lower parallel portions of the U-shaped cross-section member is joined thereon, and this is continuously arranged or laminated, and then, the other is joined to an adjacent plate to form a plate. The method for producing a leaf-shaped plate heat exchanger according to any one of claims 1 to 5 and 16 to 17, which is a group.