JPH02192873A - Heat exchanger - Google Patents

Abstract

PURPOSE:To allow brazing in the state of low strain by forming coating layers consisting of the same material as fin materials on the surface of tubes and brazing the fins and tubes which are different in material from each other. CONSTITUTION:The corrugated aluminum fins 1 and the thin long-sized tubes 2 made of SUS 304 are used in the case of producing the heat exchanger. The aluminum coating layers 4 are formed by physical vapor deposition on the surfaces of the tubes 2. The aluminum fins 1 and the tubes 2 having the aluminum coating layers 4 are then brazed in brazing parts 4. The aluminum fins 1 and SUS 304 tubes 2 which are different in material are brazed to each other via the aluminum coating layers 4 and, therefore, the secure brazing is executed in the state of low strain; in addition, the operation thereof is easy. The high- quality heat exchanger having no brazing defect parts is thus obtd. by the simple operation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat exchanger iK comprising tubes and fins made of dissimilar metals.

[Conventional technology]

Conventionally, in a heat exchanger that has fin materials and tubes made of different materials, for example, a heat exchanger that has aluminum corrugated fins 1 and water tubes made of SUS 304 tubes 2 as shown in Fig. 2, the wax between the fins 1 and the tubes 2 is There are various problems with attaching it.

That is, in this type of heat exchanger, as shown in FIG. 3, the aluminum corrugated fins 1 and the SUS 304 tubes 2 are brazed together at the portions shown at 13.

[Problem to be solved by the invention]

In this kind of thin-walled, lightweight, high-density heat exchange zone,
5US3 with aluminum corrugated fins as above
When brazing the 04 tube, there was a risk of deterioration in strength due to the formation of defective parts and leakage of steam and other gases due to the formation of pinholes between the thin fins and the tube.

The present invention aims to solve the above-mentioned problems of conventional heat exchangers.

[Means to solve the problem]

The present invention is a heat exchanger in which fins are brazed to tubes made of a different material from the fin material, in which a coating layer made of the same material as the fin material is formed on the surface of the tube, and the fins are brazed to this.

[Effect]

In the present invention, by forming a coating layer made of the same material as the fin material on the surface of the tube and brazing the fin to the tube having this coating layer, the fin and the tube made of a different material can be easily brought together in a low-distortion state. It can be brazed with. Therefore, no defective parts occur during brazing, and a compact heat exchanger with a complicated shape can be easily manufactured.

〔Example〕

FIG. 1 is an enlarged view of the brazing part of one embodiment of the present invention.

The present embodiment relates to a heat exchanger as shown in FIG. 2, and as shown in FIG.
It is equipped with The surface of the tube 2 is coated with physical vapor deposition (PV).
D), an aluminum coating layer 4 having a thickness of approximately several hundred μm is formed. Further, as the aluminum fin 1, a plating sheet material is used that does not require addition of a brazing material or flux during brazing.

The above aluminum fins: /1. ! = A tube 2 made of 5US304 with a fulminium coating layer 4 is brazed in the mounting section 4 shown in FIG.

In this example, aluminum fins 1 and 5US made of different materials are used.
Since the tubes 2 made of 304 are brazed to each other via the aluminum coating layer 4 of the open tube 2, they are firmly brazed with low strain and are easy to work with. Therefore, in this embodiment, a high-quality heat exchanger with no defective parts can be obtained by brazing with a simple operation.

Incidentally, when brazing the fin 1 and the tube 2, it is preferable to perform the brazing in a high vacuum or in an inert gas atmosphere in order to improve the quality of the parts.

Further, in the above embodiment, a plating sheet material is used as the aluminum fin 1, but a normal aluminum sheet material may be used and the fin and the tube may be brazed using a brazing material and flux. .

〔Effect of the invention〕

The heat exchanger of the present invention has the following effects because a coating layer made of the same material as the fin material is formed on the tube surface and the fins and tubes made of different materials are brazed to each other. Can be done.

(1) Fins and tubes made of different materials can be easily and reliably brazed together.

(2) It is possible to join the tubes and fins with low distortion, and it is possible to easily manufacture compact high-density integrated heat exchangers with complex shapes.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the brazing part between the fin and the tube in one embodiment of the present invention, and Fig. 2 is an explanatory diagram of the brazing part between the fin and the pipe, and Fig. 2 shows the aluminum fin and the 5US304
FIG. 3 is an explanatory diagram of a heat exchanger having a tube made of aluminum. 1... Aluminum corrugated fin, 2... SU
S 304 pipe, 3...brazing part, 4...aluminum coating layer.

Claims (1)

[Claims] A heat exchanger in which fins are brazed to tubes made of a different material from the fin material, characterized in that a coating layer made of the same material as the fin material is formed on the surface of the tube, and the fins are brazed to this coating layer. Heat exchanger.