JP2006010131A - Joining method of pipe and plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joining method easy in assembling, simple in a structure, and manufacturable by a simple facility, in the joining method for brazing and fixing its inserting part by inserting a pipe 3 into a pipe inserting hole 2 of a plate 1. <P>SOLUTION: The pipe inserting hole 2 of the plate 1 is formed a little larger than the outer periphery of a pipe 3, and three or more claw parts 4 are integrally projected on the inner periphery of its pipe inserting hole 2. Its inserting part is brazed and fixed in a state of holding the outer periphery of the pipe 3 by the claw parts 4 by inserting the pipe 3 into the pipe inserting hole 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a joining method in which one end of a pipe, like a pipe protruding from a tank of a heat exchanger, is inserted into a pipe insertion hole of a plate constituting the tank and the insertion part is brazed and fixed.

The metal tank of the heat exchanger has a tank body with a plate formed in a box shape, and the opening is closed with a tube plate. An inlet for the heat exchange medium is formed on one side of the tank body, and one end of the pipe is inserted into the inlet, and the insertion portion is integrally brazed and fixed. In addition, a large number of tubes pass through the tube plate, and fins are arranged between the tubes to constitute a heat exchanger core.
In such a metal tank and heat exchanger core, at least one surface to be joined to each other is coated with a brazing material, or a brazing material is disposed at a joint portion and inserted into a high-temperature furnace, and between each component. Are brazed and fixed together. The tank and the pipe can be joined separately from the core brazing process.

Such assembly of the pipe and the tank has been conventionally performed as follows. The opening of the pipe insertion hole of the tank is formed to be extremely slightly smaller than the outer periphery of the pipe, and one end of the pipe is press-fitted into the pipe insertion hole, thereby holding the pipe in the tank.
As another assembling method, the flange portion 6 of FIG. 2A is bent and formed on the outer periphery of the opening end portion of the pipe. Then, the pipe insertion hole 2 of the tank is formed to be slightly larger than the outer periphery of the pipe 3, and the end of the pipe 3 is inserted into the pipe insertion hole 2. Next, the opening edge of the pipe 3 is expanded as shown in FIG. 2B, and the expanded portion 7 is formed there. Thereby, the pipe 3 is held in the pipe insertion hole 2 of the plate 1.

The former method of joining the pipe and the plate has a drawback that the fitting tolerance between the outer periphery of the pipe 3 and the pipe insertion hole 2 of the plate 1 is strictly required, and the manufacturing cost of the parts is increased.
Further, the latter joining method has the disadvantages that the formation of the flange portion 6 and the formation of the expanded portion 7 are troublesome, and the number of assembling steps increases, and the manufacturing cost increases from that point.
Furthermore, both of them require equipment costs and an appropriate jig for each pipe size.
Therefore, the present invention is easy to assemble, can reliably hold the outer periphery of the pipe 3 in the pipe insertion hole 2, and can be reliably brazed between the two at the time of brazing. It is an object of the present invention to provide a bonding method that can perform the above.

The present invention according to claim 1 is the joining of a pipe and a plate, in which the pipe (3) is inserted into the pipe insertion hole (2) drilled in the plate (1) and the insertion portion is brazed and fixed. In the method, the pipe insertion hole (2) is formed to be slightly larger than the outer periphery of the pipe (3), and at least three claw portions (in the circumferential direction are spaced apart from the inner periphery of the pipe insertion hole (2)). 4) projecting integrally and forming the claw portion (4) so that the tip of the claw portion (4) is located slightly on the center side from the outer periphery of the pipe (3);
Next, the step of inserting the pipe (3) into the pipe insertion hole (2) and brazing and fixing the insertion part while holding the outer periphery of the pipe (3) by the claw part (4), It is the joining method of the pipe and plate which have.

The present invention according to claim 2 is the method according to claim 1,
The pipe insertion hole (2) is composed of a pair of parallel portions (2a) facing each other and a pair of arc portions (2b) connecting both ends thereof, and the claw portion (4) is an arc portion (2b). This is a joining method of a pipe and a plate configured to be located at or near the beginning.
The present invention described in claim 3 provides the method according to claim 2,
In this method, the pipe and the plate are joined such that the claw portion does not exist in the intermediate portion of the parallel portion (2a).

The present invention according to claim 4 provides the method according to claim 2,
This is a joining method of a pipe and a plate in which the claw portion (4) is also formed at an intermediate position of the arc portion (2b).
According to the fifth aspect of the present invention, the pipe insertion hole (2) comprises a circular hole, the circular hole is divided into three or more, and the claw portion (4) is formed at each division point. Is a method of joining the plate and the plate.

  In the joining method of the present invention, three or more claw portions 4 are integrally projected in the pipe insertion hole 2, the tip of the claw portion 4 is located slightly on the center side from the outer periphery of the pipe 3, and the pipe insertion hole Since 2 is formed slightly larger than the outer periphery of the pipe 3, the pipe 3 can be easily inserted into the pipe insertion hole 2. And the clearance gap between the outer periphery of the pipe 3 and the pipe penetration hole 2 can be hold | maintained equally by hold | maintaining the outer periphery of the pipe 3 with the 3 or more nail | claw parts 4. FIG. As a result, the brazing reliability can be improved without brazing the brazing material to one side during brazing. At the same time, it is possible to provide a joining method that is easy to manufacture and requires a small number of work steps.

In the above configuration, the shape of the pipe insertion hole 2 can be constituted by a pair of parallel portions 2a and a pair of arc portions 2b, and the claw portion 4 can be arranged at the start of the arc portion 2b or in the vicinity thereof.
In this case, since the nail | claw part 4 is arrange | positioned in the part which cannot deform | transform comparatively with a pipe, the reliability of brazing can be improved.
In the above configuration, when the claw portion is not present in the middle portion of the parallel portion 2a, the brazing reliability can be further improved.

In the above configuration, the claw portion 4 can be formed at an intermediate position of the arc portion 2b. Accordingly, the pipe 3 can be reliably held in the pipe insertion hole 2 and the brazing reliability can be improved.
In the above configuration, the pipe insertion hole 2 can be a circular hole, the circular hole can be divided into three or more, and the claw portions 4 can be arranged at the respective dividing points.
By doing in this way, the outer periphery of a circular pipe can be hold | maintained uniformly, the clearance gap between the pipe penetration hole 2 and the outer periphery of the pipe 3 can be hold | maintained uniformly, and the reliability of brazing can be improved.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 (A) is a front view of an essential part showing the assembled state of the pipe and plate of the present invention (pipe is shown in cross section), (B) is an enlarged view of B part of (A), (C ) Is a cross-sectional view taken along the line CC of (B).
In this joining method, the pipe insertion hole 2 of the plate 1 and the outer periphery of the cross section of the pipe 3 are formed in an elliptical shape. That is, the pipe insertion hole 2 includes a pair of parallel portions 2 a and a pair of arc portions 2 b that connect between the ends of both parallel portions 2 a, and the outer periphery of the pipe insertion hole 2 is slightly larger than the outer periphery of the pipe 3. Is formed. A pair of claw portions 4 are provided so as to protrude from each other at two positions, that is, both end positions of the parallel portion 2a of the pipe insertion hole 2 and an intermediate position of each arc portion 2b. The claw portion 4 can be integrally formed in a pressing process for forming the pipe insertion hole 2 in the plate 1. Alternatively, after the pipe insertion hole 2 is formed, the claw portion 4 may be integrally protruded by plastic deformation of a part of the hole edge of the pipe insertion hole 2.

The claw portion 4 is formed in a triangular shape or the like in plan view, and its tip protrudes slightly to the center side from the outer periphery of the pipe 3. In this example, the outer periphery of the pipe 3 is coated with a brazing material 5 in advance. Instead, a brazing material may be coated on the plate 1 side. Moreover, you may arrange | position the brazing material 5 of a linear or foil shape between both.
Such a pipe 3 is inserted into the pipe insertion hole 2 of the plate 1. Then, the claw portion 4 projecting from the inner periphery of the pipe insertion hole 2 is engaged with the outer periphery of the pipe 3, and the pipe 3 is held in the pipe insertion hole 2.

A slight gap is formed between the pipe 3 assembled in this way and the pipe insertion hole 2 of the plate 1, but by making the projections of the claw portions 4 equal, the outer periphery of the pipe insertion hole 2 and the pipe 3 Can be kept uniform. In FIG. 1, the gap between the two is large for convenience of explanation, but in practice, the gap is hardly visible.
Then, the assembled plate 1 and the pipe 3 are inserted into a high-temperature furnace, the brazing material 5 is melted, and then cooled and solidified, whereby the outer periphery of the pipe 3 and the pipe insertion hole 2 of the plate 1 are formed. The inner periphery can be brazed and fixed integrally.
In the above example, the outer periphery of the pipe 3 and the pipe insertion hole 2 are formed in an elliptical shape, but both may be formed in a circular shape instead. In that case, the pipe insertion hole 2 may be divided into three or more, and the claw portions 4 may be integrally projected at each division point.

  In the heat exchanger thus constructed, a hose or the like is connected to the tip opening of the pipe 3, and the heat exchange medium is supplied into the plate 1 constituting a part of the tank through the pipe 3, and then shown in the figure. Do not divert to each tube. And cooling air is distribute | circulated to the outer surface side of a tube and a fin, and heat exchange is performed between the cooling air and a heat exchange medium.

It is explanatory drawing which shows the 1st procedure of the brazing process of the joining method of this invention, Comprising: The front view (The pipe 3 is made into a cross section) which shows the state which penetrated the pipe 3 in the pipe penetration hole 2 of the plate 1, and its B Part enlarged view and CC sectional view. The longitudinal cross-section schematic which shows the joining procedure of a conventional type pipe and a plate in order.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Plate 2 Pipe insertion hole 2a Parallel part 2b Arc part 3 Pipe 4 Claw part 5 Brazing material 6 Flange part 7 Expansion part

Claims (5)

In the joining method of the pipe and the plate for inserting the pipe (3) into the pipe insertion hole (2) drilled in the plate (1) and brazing and fixing the insertion portion,
The pipe insertion hole (2) is formed slightly larger than the outer periphery of the pipe (3), and at least three claw portions (4) are spaced circumferentially from the inner periphery of the pipe insertion hole (2). A step of projecting integrally and forming the claw portion (4) so that the tip of the claw portion (4) is positioned slightly on the center side from the outer periphery of the pipe (3);
Next, the step of inserting the pipe (3) into the pipe insertion hole (2) and brazing and fixing the insertion part while holding the outer periphery of the pipe (3) by the claw part (4), The joining method of the pipe and plate which have. In claim 1,
The pipe insertion hole (2) is composed of a pair of parallel portions (2a) facing each other and a pair of arc portions (2b) connecting both ends thereof, and the claw portion (4) is an arc portion (2b). A method of joining pipes and plates located at or near the beginning. In claim 2,
A method for joining a pipe and a plate configured such that the claw portion (4) does not exist in an intermediate portion of the parallel portion (2a). In claim 2,
A method for joining a pipe and a plate in which the claw portion (4) is formed also at an intermediate position of the arc portion (2b). In claim 1,
A method of joining a pipe and a plate, wherein the pipe insertion hole (2) is a circular hole, the circular hole is divided into three or more, and the claw portion (4) is formed at each division point.

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