JPH07190649A - Plate type heat exchanger - Google Patents

Abstract

PURPOSE:To improve heat transfer efficiency and rigidity by a method wherein a multitude of thin formed plates, having wavy or uneven cross sections, are piled to form bag type heat transfer plates and slanted wall surfaces having parallel parts are provided around the heat transfer plates while the engaged condition of the heat transfer plates is formed by the slanted wall surfaces to laminate the plates and receive them into a vessel. CONSTITUTION:A wavy thin plate 11a, having horizontal parts and a slanted wall surface around the circumference thereof, is combined with another wavy thin plate 11b, having a horizontal part and slanted wall surface, a wavy thin plate 12a is combined with a wavy thin plate 12b and a wavy thin plate 13a is combined with a wavy thin plate 13b, then, circumferential connecting parts (d) and connecting parts (c) in a passage inlet port and a passage outlet port are welded respectively to form heat transfer plates 11, 12, 13,... so as to have the shape of a bag. A plurality sets of the heat transfer plates are laminated and the laminates are engaged at the slanted wall surface while sealed parts (e) are formed around the circumference of the thin plates. The wavy thin plate 11a is welded to an introducing tube, the plate 11b welded to the plate 12a, the plate 12b is welded to the plate 13a respectively at the passage inlet port and the passage outlet port so that fluids, flowing through the passage inlet port and the passage outlet port, will never be mixed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger, and more particularly to a plate heat exchanger formed by stacking heat transfer plates.

[0002]

2. Description of the Related Art In the prior art, for example, Japanese Patent Laid-Open No.
As disclosed in the plate heat exchangers described in JP-A-0-71849 and JP-A-61-2122494, welding and welding are performed at the outer peripheral portion of a heat transfer plate group formed by stacking a large number of heat transfer plates. All the contact surfaces form a sealed state by brazing or by inserting a gasket and joining.

[0003]

In the above-mentioned conventional technique, when the pressure of the fluid in the heat transfer plate increases, the internal pressure is received, so that the rigidity of the heat transfer plate is increased and the shape of the heat transfer plate is maintained. It was necessary to increase the plate thickness. Due to this increase in plate thickness, there are problems that the efficiency of heat transfer is reduced, the material cost is increased, and the heat exchanger is upsized.

Furthermore, there are problems in that the number of welding and brazing points and the number of gaskets are large, resulting in a decrease in accuracy, an increase in manufacturing time, and an increase in material cost.

An object of the present invention is to reduce the thickness of a heat transfer plate composed of corrugated thin plates to improve heat transfer efficiency and to manufacture a low cost plate heat exchanger. It is to obtain a structure of a heat exchanger that secures sufficient strength and rigidity against the pressure of fluid, has the minimum number of necessary components and the number of working steps, and has a small external dimension.

[0006]

In order to achieve the above-mentioned object, the structure of the present invention has a structure in which two thin forming plates having a large number of corrugations or a large number of concave and convex cross-sections are overlapped with each other and the surroundings and fluid passages. A bag-shaped heat transfer plate is joined to the road opening, and the bag-shaped heat transfer plate is placed in a container so as to surround the entire circumference as a heat transfer plate group in which a plurality of the heat transfer plates are laminated. Two different kinds of fluids are made to flow, and inclined wall surfaces having parallel portions are provided around the bag-shaped heat transfer plate, and when the bag-shaped heat transfer plates are stacked, the inclined wall surfaces are respectively fitted. It was characterized by forming a state.

[0007]

The stacking structure having the inclined wall surface eliminates the insertion of the gasket found in the prior art. And, the part parallel to the heat transfer plate provided on the tip of the inclined wall surface is for the purpose of avoiding melting and deformation of the inclined wall surface in the case of welding in the joining work to ensure the accuracy of the fitting surface, and in the case of brazing, it is a brazing material. It has a structure that meets the construction requirements such as the installation stand and the molten wax pool.

Further, by providing the bulge portion at the position where the bag-shaped heat transfer plate and the inclined wall surface are in contact with each other, the shape of the bag-shaped heat transfer plate at the time of stacking can be maintained, and consequently the deterioration of the heat transfer performance can be avoided. Further, it becomes possible to further reduce the thickness of the corrugated thin plate.

[0009] The bag-shaped heat transfer plates contact each other during stacking from the inclined wall surface portion provided around the bag-shaped heat transfer plate to the above-mentioned bulge portion, forming a so-called surface contact. There is. This has the advantage that the degree of sealing is higher than that of so-called point contact in which only one point is in contact. The high degree of airtightness means that the flow rate flowing through the gap between the bag-shaped heat transfer plate and the container is small, and therefore the heat transfer performance can be improved.

When a plurality of sets of heat transfer plates are laminated and the slanted wall surfaces are fitted to each other, the higher fluid (A, B) of the two fluids (A, B) to be circulated to the heat exchanger is flown to the heat exchanger (when there is a pressure difference). Temporarily, B) is flown here, and at the same time, the same fluid B is also filled in the container containing the heat transfer plate group.

That is, since the slanted wall fitting portion is formed in a close contact state, a large amount of fluid is prevented from flowing out in the inner and outer portions thereof, but there is some outflow because it is not completely sealed. This is because. Therefore, the pressure applied to the inner wall of the container and the pressure of the internal space fitted by the inclined wall surface are kept the same. The B-fluid having a higher pressure, which is filled in the container and circulated in the laminated portion of each heat transfer plate, acts as an external pressure so that a large number of uneven contact points distributed on the corrugated thin plate are constantly brought into contact with each other, and stress generated in the thin plate・ The deformation can be reduced. As a result, the accuracy of the heat exchanger is maintained and stable performance can be obtained.

[0012]

An embodiment of the present invention will be described below with reference to the drawings. First, FIG. 3 shows a top view of the plate heat exchanger, and FIG. 4 is a cross-sectional view of the fluid inlet / outlet portion of the heat exchanger.
Fig. 5 shows a partial surface roll 'of the central part of the heat exchanger.

In FIG. 3, the heat transfer plate group 1 is housed in a container 7 whose periphery is welded 8, and the fluid A for heat exchanger is a corrugated thin plate that enters from the passage inlet 2a of the introduction pipe 3. The fluid B flows between the heat transfer plates to the passage outlet 2b, and the fluid B flows from the passage inlet 4a of the introduction pipe 5 between the heat transfer plates to form the passage outlet 4b.

The structure of the heat transfer plate group 1 which is the main body of the present invention is as follows.
As an enlarged view of the circular portion in FIG. 4 and FIG. 4, a welding type is shown in FIG. 1 and a brazing type is shown in FIG. From the figure, corrugated thin plates 11a, 11b, 12 having horizontal portions and inclined wall surfaces in the periphery
a and 12b, 13a and 13b, ... are combined in advance, and the d portion which is the peripheral joint and the passage inlet 4
a, a portion c which is a joint at the passage outlet 4b is welded or brazed and joined together to form the heat transfer plates 11, 12,
By forming a bag shape of 13 ... and stacking a plurality of sets thereof and fitting them on the inclined wall surface, a contact portion e is formed in the periphery. Next, at the passage inlet 2a and the passage outlet 2b, the corrugated thin plate 11a and the introduction pipes 3, 11b and 12a, 12b and 1 are provided.
3a are welded or brazed to each other so that the passage inlet 4a and the passage outlet 4b do not mix with the flowing fluid.

Referring to FIGS. 4 and 5, the flow of the fluid in the above structure is such that first, the fluid A enters the passage port 2a from the introduction pipe 3 joined to the heat transfer plate 11a, between 11a and 11b, and 12a.
And 12b, between 13a and 13b, ... In the longitudinal direction of the heat transfer plate (from the bottom to the top in FIG. 1), the fluid flows out to the passage port 2b. During this period, the heat transfer plates 11, 12, 13, ... Have a bag-like shape in which the peripheral portion and the passage opening are completely joined, so that no fluid flows out.

Next, the fluid B enters the passage opening 4a from the introduction pipe 5 welded 9 to the outer cylindrical container 7 and is mostly heat transfer plates 11 and 12.
, 12 and 13, and 13 and n to flow toward the fluid A (from top to bottom in FIG. 1) to the passage port 4b for heat exchange. Then, a part of it flows out from the gap of the ring-shaped spacer ring 6 (not joined) provided between the inner wall of the outer cylindrical container 7 and the heat transfer plate 11, and the heat transfer plates 11, 1
Since there is a slight outflow from the fitting contact portion e on the inclined wall surfaces 2, 13, ..., The B fluid fills the gap between the heat transfer plate group 1 and the container 7, and therefore the container 7 The pressure applied to the inner wall of the inner wall and the pressure of the inner space fitted by the inclined wall surface keep the same pressure.

If there is a pressure difference between the fluids A and B, the fluid with the higher pressure is designated as fluid B. As a result, the heat transfer plates 11, 12, 13, ...
.. receives a force from the outside, and the corrugated irregularities are always in contact as shown in FIG. And the plate type heat exchanger with high reliability can be obtained because the dimension and accuracy of the uneven shape which can be said to be the life of heat exchanger efficiency are secured.

It is also possible to use the heat exchanger in the opposite manner to the above, that is, the one having a lower pressure is the B fluid and the one having a higher pressure is the A fluid.

Also, the smaller the thickness of the heat transfer plate, the more the bag-shaped heat transfer plate is fitted and stacked, and the space between the horizontal portion of the bag-shaped heat transfer plate and the inclined wall surface is crushed. This easily deteriorates the heat transfer performance of this portion, and causes the bag-shaped heat transfer plates to have different sizes in the upper part and the lower part of the stacked heat transfer plate group 1. For this reason, the bulged portion f shown in FIGS. 1 and 2 is provided, and even when a large force is applied during lamination, the dimensional shape of the bag-shaped heat transfer plate does not change, and therefore, deterioration of heat transfer performance is prevented. You can

The horizontal shape provided at the tip of the inclined wall surface around the heat transfer plate is a position where the welding heat does not affect the fitting surface in the welding type in the case of forming as shown in FIG. 1, and the corrugated thin plates 11a and 11b. , 12a and 12b, 13a and 13b, ...
・ ・ The shape and dimensions are such that a welded joint in which both are face-matched at the plate end can be prepared.

Similarly, in the brazing type shown in FIG. 2, a brazing material is installed on the brazing part of the inclined wall surface (working is done with the posture of brazing upside down in FIG. 2) and melting. It also has the shape of a row of low rows and has a horizontal shape with a proper amount of clearance. Reference numeral 10 in the figure affects the heat exchange efficiency when a large amount of flow phenomenon of the fluid filled in the space inside the heat transfer plate group 1 and the outer cylinder container 7 occurs, so a spacer plate inserted to prevent this occurs. Is.

[0022]

Since the present invention is configured as described above, it has the following effects. (1) The slanted wall surface provided around the corrugated thin plate facilitates the combination, thus reducing the manufacturing time, and as a heat transfer plate, the wall surface is highly reliable for brazing and the horizontal portion is the fitting surface. Welding work can be performed while maintaining accuracy. Therefore, the quality can be improved.

Further, by providing a bulge at a position where the bag-shaped heat transfer plate and the inclined wall surface are in contact with each other, it is possible to maintain the shape of the bag-shaped heat transfer plate at the time of stacking and reduce the thickness of the corrugated thin plate. Becomes

(2) A gasket is not used in the inclined wall surface portion as a heat transfer plate group in which a plurality of sets of heat transfer plates are laminated, and therefore the material cost can be reduced. In addition, due to a slight leak at the fitting contact surface, pressure is formed by the fluid filled in the container and the corrugated irregularities of the heat transfer plate are constantly in contact with each other, so that the heat transfer performance is improved.

(3) With the structure of the above item (2), the stress acting on the base material and the joint portion of the welded or brazed joint is greatly reduced, so that the thickness of the corrugated thin plate is reduced and the heat exchange efficiency is improved. It is possible to mass-produce a small, plate-type heat exchanger that is expensive and inexpensive.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view (welding type) of a plate heat exchanger of the present invention.

FIG. 2 is an enlarged cross-sectional view (type with brazing) of the plate heat exchanger of the present invention.

FIG. 3 is a top view showing the entire plate heat exchanger of the present invention.

FIG. 4 is a cross-sectional view taken along the line EE ′ of FIG.

FIG. 5 is a cross-sectional view as seen from the roll's surface of FIG.

[Explanation of symbols]

1 ... Heat transfer plate group, 2, 4 ... Fluid passage port 3, 5 ... Introducing pipe, 6 ... Spacer ring 7 ... Container, 8, 9 ... Welding 10 ... Spacer plate, 11a, 11b, 12a, ... Corrugated thin plate Heat transfer plate, 11, 12, 13, ... N ... Bag-shaped heat transfer plate, c, d ... Welded or brazed part, e ... Non-bonded contact part f ... Swelling part

Claims (5)

[Claims] 1. A bag-shaped heat transfer plate obtained by stacking two thin plate molding plates having a large number of corrugations or a large number of uneven cross-sections, and joining the periphery and fluid passage openings to form a bag-shaped heat transfer plate. A heat transfer plate group in which a plurality of heat plates are laminated is placed in a container so as to surround the entire circumference, and two kinds of fluids having different temperatures are allowed to flow through the thin plate forming plate, and the periphery of the bag-shaped heat transfer plate. A plate-type heat exchanger, characterized in that an inclined wall surface having a parallel portion is provided on the plate, and when the bag-shaped heat transfer plates are stacked, the inclined wall surfaces form a fitted state. 2. The plate heat exchanger according to claim 1, wherein the bag-shaped heat transfer plate has an inclined wall surface having a parallel portion, and between the bag-shaped heat transfer plate and the inclined wall surface. Forms a bulge portion for maintaining the shape of the bag-shaped heat transfer plate, and the bag-shaped heat transfer plates are in contact with each other even in the bulged portion when the bag-shaped heat transfer plates are stacked. Plate type heat exchanger characterized by. 3. The plate heat exchanger according to claim 1 or 2, wherein the peripheral and fluid passage ports of two thin plate sheets having a large number of corrugations or a large number of irregular cross sections are welded. A plate heat exchanger characterized by being joined. 4. The plate heat exchanger according to claim 1 or 2, wherein two thin formed plates having a large number of corrugations or a large number of concave and convex cross sections are brazed around the periphery and fluid passage ports. A plate-type heat exchanger characterized by being joined by. 5. The plate heat exchanger according to claim 1, 2, 3 or 4, wherein when the pressures of two kinds of fluids flowing into the heat exchanger have a difference, The fluid enters the inside of the bag-shaped heat transfer plate, and the fluid with the higher pressure flows outside the bag-shaped heat transfer plate and in the container that stores the stacked bag-shaped heat transfer plates. A plate heat exchanger, characterized in that it enters into a gap between an inner wall and the bag-shaped heat transfer plate which is superposed.