JP3027027B2 - Plate heat exchanger - Google Patents

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 plate-type heat exchanger requiring a high pressure and having excellent rigidity and improved liquid tightness. The present invention relates to a plate type heat exchanger.

[0002]

2. Description of the Related Art In general, a plate heat exchanger (a)
As shown in FIG. 5, a plurality of plates (5) having a heat transfer surface (2) in the form of a corrugated plate (not shown) and having openings (5), (5), (5), and (5) at four corners ( 1) (1) are alternately stacked via gaskets (3) and (3) to form a first flow path (A) and a second flow path (B) alternately between plates, A heat exchange is performed between them.

For holding the plates (1) and (1) in a stacked state, for example, as shown in FIGS. 6 and 7, guide bars (10) and (10) are connected to a first frame (11) and a support rod. (19) A plurality of plates (1) (1) and gaskets (3) (3) are alternately provided between the first frame (11) and the second frame (12) opposed to the first frame (11). The notches (4) and (4) arranged at the center of both short sides of the plates (1) and (1) are respectively inserted into the guide bars (1).
The plates (1) and (1) are held between the first frame (11) and the second frame (12) by engaging with 0) and (10).

In this state, a plurality of long bolts (13) are inserted between the first and second frames (11) and (12) as shown in FIG.
3) First and second frames (11) and (12) by screwing a nut (14) into the screw portion at the tip and tightening the nut.
Plates (1) and (1) stacked with gaskets (3) and (3) between them are sandwiched therebetween.

The first frame (11) has a first inflow hole (15) and a first discharge hole (1) communicating with the first flow path (A).
6) and a second inflow hole (1) communicating with the second flow path (B).
7), a second discharge hole (18) is provided.

[0006]

The first flow path (A) and the second flow path (B) of the plate heat exchanger (a) having the above structure.
When the first fluid (a) and the second fluid (b) are supplied to each other, and heat exchange is performed between the two fluids, the plate heat exchanger (a) is used, for example, for air conditioning of a skyscraper. When used as a heat exchanger for the equipment, the primary side
The pressure of the first fluid (a) flowing through the flow path (A) is 4 to 5 k
g / cm ² , but the pressure of the second fluid (b) flowing through the second flow path (B) on the secondary side is 60 to 80 kg / cm ^2.
Becomes

As described above, a large pressure difference is generated between the first fluid (a) and the second fluid (b), so that the first fluid (a) <the second fluid (b) and the first fluid (A) ) When the first fluid (a) is supplied to the second flow path (B) and the second fluid (b) is supplied, the heat transfer surfaces (2) and (2) of each of the plates (1) and (1).
Is deformed as shown by the broken line in FIG.

That is, the fluid pressure of both fluids is the first fluid (a)
<Because it is the second fluid (b), the pressure in the second flow path (B) is higher than the pressure in the first flow path (A), and the load in the direction of the arrow in the drawing is large. The contact points (a ′) and (b ′) in contact with the heat transfer surface (2) adjacent to the heat transfer surface (2) are greatly deformed, as shown by the broken lines in FIG. There has been a problem in that the flow path interval of the first flow path (A) is reduced, or the liquid tightness in the second flow path (B) is reduced by the gasket (3).

Further, depending on the type of the plate-type exchanger (a), instead of using only the gasket (3) for securing the liquid tightness of the first flow path (A) and the second flow path (B), it is not possible to use the gasket (3). The two plates (1) and (1) are welded and fixed at a portion where the conventional gasket (3) is interposed, and the two plates are stacked via a gasket to form a plate-to-plate relationship. In some cases, the flow path whose liquid-tightness is ensured by welding and the flow path whose liquid-tightness is ensured by a gasket are alternately arranged. Even in this case, only the periphery of the plate (1) is welded. Therefore, deformation of the plate heat transfer surface (2) due to the pressure difference between the two fluids supplied to the two flow paths cannot be avoided.

When the periphery of the plate (1) is welded,
At the same time, it takes a very long time to perform the welding operation, and it is very difficult to keep the welding quality constant.

[0011]

According to the present invention, two plates having a heat transfer surface are laminated, and a portion surrounding the heat transfer surface between the two plates and a contact portion between the heat transfer surfaces are formed of a brazing material. And a gasket interposed between the heat transfer elements when the heat transfer elements are stacked, and a second flow passage formed in each of the heat transfer elements Is a flow path for the fluid on the high pressure side, the first flow path surrounded by the gasket between the heat transfer elements is a flow path for the fluid on the low pressure side, and both are alternately formed.

[0012]

According to the present invention having the above-described structure, each heat transfer element serving as a flow path for the fluid on the high pressure side has a portion surrounding the heat transfer surfaces of the two plates, and a portion surrounding both heat transfer surfaces. When the contact part is brazed and fixed with a brazing material, when heat exchange is performed between the high-pressure fluid and the low-pressure fluid having a large pressure difference, it is possible to prevent deformation of the heat transfer surface and improve liquid tightness. Thus, a plate heat exchanger suitable for heat exchange between fluids having a large pressure difference can be provided.

[0013]

FIG. 1 shows a main part of a plate heat exchanger (b) according to the present invention.

The plate type heat exchanger shown in this figure (b)
Are the portions (3) of the two plates (21) and (21) surrounding the heat transfer surface, where the gasket was conventionally interposed.
1) and a contact portion (32) serving as an intersection between the plate heat transfer surfaces (22) and (22) is fixed by brazing;
A pair of heat transfer elements (30) having a second flow path (B) for fluid passage therein is formed.

Then, this heat transfer element (30) is
By laminating via a gasket (23) similar to the conventional one, a plate heat exchanger (b) in which first flow paths (A) and second flow paths (B) are alternately formed is formed. It was done.

The heat transfer element (30) is, as shown in FIGS. 2 and 3, a portion (31) between the two plates (21) where a conventional gasket is interposed, that is, a broken line in the drawing. The brazing material (33) is interposed in the portion shown in (1), and the brazing material (34) is also interposed in the contact portion (32) between the plate heat transfer surfaces (22) and (22).

The two plates (21) and (21) with the brazing materials (33) and (34) interposed therebetween are heated in a heating furnace to melt the brazing materials (33) and (34). The two plates (21) and (21) are soldered and fixed in a liquid-tight manner.

When the brazing material (34) interposed between the contact portions (32) of the plate heat transfer surfaces (22) and (22) is melted,
The brazing material (34) gathers in the gap around the contact portion (32) by capillary action to form a joint having a large area,
This part is firmly bonded.

Further, the brazing material (3
3) For (34), for example, a brazing material such as a Ni-based or copper-based material may be used.

In the figure, reference numeral (24) denotes a plate (21).
The notch provided at the center of both short sides of (2), (25) are openings provided at four corners.

A plurality of heat transfer elements (30) formed as described above are assembled, and the same gasket (23)
And a second flow path (B), which is held in the same manner as before, and is kept liquid-tight by the brazing material (33);
The first flow path (A), which is kept liquid-tight by the gasket (26), is alternately formed, and a high-pressure second fluid (b) is supplied to the second flow path (B). If the low pressure first fluid (a) is supplied to the passage (A), the deformation of each plate (21) can be prevented.

That is, a load in the direction of the arrow is generated in the second flow path (B) to which the high-pressure second fluid (b) is supplied, as in the conventional case. Outer periphery is brass (3
3), and the contact portions (32) of the heat transfer surfaces (22) and (22) forming the second flow path (B) are also welded by the brazing material (34). Since the brazing members (33) and (34) are supported, deformation of the plate (21) can be prevented.

[0023]

As described above, if the second flow path formed in the plate heat exchanger is surrounded by the brazing material and the contact portion between the opposed heat transfer surfaces is brazed and fixed,
There is a large pressure difference between the first and second fluids supplied to the first and second flow passages, and even if a load generated by the pressure difference is applied to the heat transfer surface of the plate, the load remains at the second flow rate. Since it can be supported by the brazing material surrounding the outer periphery of the path and the brazing material interposed in the contact portion of the heat transfer surface, the plate can be reliably prevented from being deformed.

Further, the two plates constituting the heat transfer element are brazed and fixed by a brazing material, so that a large number of heat transfer elements can be formed at one time at a time, so that the productivity is good and the quality is high. As a result, a plate heat exchanger having excellent pressure resistance and rigidity can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a plate configuration of a plate heat exchanger according to the present invention.

FIG. 2 is a front view showing a heat transfer element.

FIG. 3 is a cross-sectional view of a heat transfer surface of the heat transfer element.

FIG. 4 is a sectional view of a heat transfer surface of the plate heat exchanger according to the present invention.

FIG. 5 is an exploded perspective view showing a plate configuration of a conventional plate heat exchanger.

FIG. 6 is a side view showing one example of a plate heat exchanger.

FIG. 7 is a front view showing an example of a plate heat exchanger.

FIG. 8 is a sectional view of a heat transfer surface of a conventional plate heat exchanger.

[Explanation of symbols]

 B Plate heat exchanger A First flow path B Second flow path a First fluid b Second fluid 21 Plate 22 Heat transfer surface 23 Gasket 30 Heat transfer element 31 Part surrounding the heat transfer surface 32 Contact portion 33 Raw material 34 Raw material

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) F28F 3/08 301 F28F 3/08 311 F28D 9/00

Claims (1)

(57) [Claims] Claims: 1. A stack of two plates having a heat transfer surface,
A portion surrounding the periphery of the heat transfer surface between the two, and a heat transfer element formed by brazing and fixing a contact portion between the heat transfer surfaces with a brazing material; A gasket interposed between the elements, wherein a second flow path formed in each of the heat transfer elements serves as a flow path for a fluid on a high pressure side, and a first gasket surrounded and formed between the heat transfer elements. The plate type heat exchanger characterized in that the flow path of (1) is a flow path of a fluid on the low pressure side, and both are formed alternately.