JPH05154686A - Clad brazing filler metal - Google Patents

Abstract

PURPOSE:To reduce cost without lowering corrosion resistance of a water flow passage by joining a copper later as brazing filler metal to both sides of a clad plate obtained by joining a water corrosion resisting metallic layer to both sides of an iron. steel layer. CONSTITUTION:A metallic layer having water corrosion resistance such as stainless steel or nickel 10 is clad on both sides of an iron. steel layer 9. clad brazing filler metal 11 is obtained by cladding pure copper on both sides of this clad plate 12. Plural clad brazing filler metals formed in a prescribed shape are prepared, superimposed in plural layers as these are fitted to each other on the outer circumference, an oil flow passage 3 and the water flow passage 4 are formed and a fin 2 is incorporated in the oil flow passage 3 to obtain an oil cooler assembling maternal. Thus, each joining part of the oil cooler is closed completely and a brazed state is good.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clad brazing material for forming an oil cooler, and more particularly to a clad brazing material for reducing the cost without lowering the corrosion resistance of the water passage of the oil cooler.

[0002]

2. Description of the Related Art FIG. 3 shows a general sectional structure of a water-cooled oil cooler. This oil cooler includes a plurality of cases 1 that form an oil flow path 3 and a water flow path 4.
And the fins 2 provided in the oil flow path 3,
In order to improve the heat exchange efficiency and prevent the liquid from flowing out, the outer circumferences of the plurality of cases 1 and the case 1 and the fins 2 are joined to each other via the joining portion 5.

FIG. 4 shows a brazing filler metal 8 which provides the case 1 and the joint 5 of the oil cooler. The clad brazing material 8 is a stainless steel layer (SUS304) 7
And a copper layer 6 as a brazing material provided on both sides thereof. In the case of forming an oil cooler, a plurality of clad brazing filler metals 8 are fitted on the outer circumference, and steel fins 2 are incorporated in the oil flow path 3, and these are placed in an inert atmosphere or in a vacuum at 1100-1200.
Heat at ℃ for a predetermined time and then cool.

FIG. 5 shows an oil cooler obtained by the above method. That is, the copper layer 6 flows to the gap between the stainless (case) 7 and the fin 2 or to the contact interface around the stainless 7 to braze the outer periphery of the stainless 7 and the stainless 7 and the fin 2.

[0005]

However, according to the conventional clad brazing material, since expensive stainless steel is used for the steel material in order to obtain the water corrosion resistance of the water passage, there is a disadvantage that the cost is increased. Further, if steel (for example, a cold rolled steel plate) is used instead of stainless steel, the cost can be reduced, but steel cannot be used because it has poor water corrosion resistance.

Therefore, an object of the present invention is to provide a clad brazing material which can reduce the cost without lowering the water corrosion resistance of the oil cooler.

[0007]

In view of the above problems, the present invention has a steel layer and stainless steel joined to both sides of the steel layer in order to reduce the cost without lowering the water corrosion resistance of the oil cooler. It is intended to provide a clad brazing material in which a copper layer as a brazing material is joined to both sides of a clad plate made of a metal layer having water corrosion resistance such as nickel.

[0008]

The clad brazing material of the present invention based on the above constitution is
In addition to mainly using cheap steel, expensive stainless steel,
Cost reduction can be achieved by reducing the amount of the metal layer such as nickel having water corrosion resistance used. Also, when forming an oil cooler, even if the orientation of the clad brazing material is not taken into consideration, the water-corrosion resistant metal layers such as stainless steel and nickel that are joined to both sides of the clad plate must be placed on the water flow path side. Therefore, the water corrosion resistance of the oil cooler is not reduced.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The clad brazing material of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which a steel layer 9
And a clad plate (case) 12 made of a nickel layer 10 joined to both sides of the clad plate 12 and a copper layer 6 provided on both sides of the clad plate 12 to form a clad brazing material 11 for forming an oil cooler. . When forming an oil cooler, a ship-shaped unit formed of the clad brazing filler metal 11 is fitted on the outer periphery and used in a plurality of layers.

When the units of the clad brazing filler metal 11 are piled up in this way, and the fins 2 are incorporated into the oil flow path 3 and heated, as shown in FIG. The fins 2 incorporated in the passage 3 are brazed to each other via the joint portion 5, and the oil passages 3,
And the nickel layer 10 is exposed in the water flow path 4.

The procedure for forming the oil cooler according to the present invention will be described below. First, 0.05 mm thick nickel is clad on both sides of a 0.2 mm thick cold rolled steel plate (SPCC), and 0.02 mm thick pure copper is clad on both sides to form a clad brazing material 11. obtain.

Then, a plurality of clad brazing filler metals 11 formed in a predetermined shape (case shape) are prepared, and these are fitted on the outer periphery to be laminated in a plurality of layers to form the oil flow passage 3 and the water flow passage 4. The fins 2 made of cold-rolled steel plate having a thickness of 0.1 mm are formed in the oil passage 3 to obtain an oil cooler assembly.

This oil cooler assembly is put at 1210 ° C.
It is placed in a box-type electric furnace having an inner dimension of 150 mm × 150 mm and heated for 15 minutes while flowing 10 l / min of argon, and then cooled to form an oil cooler.

Next, the oil cooler thus formed was visually observed and subjected to a watertight test. As a result, each joint was completely sealed and the brazing condition was good. Further, water was put in the water flow path 4 of the oil cooler and left for 48 hours, but no red rust was generated.

As described above, since the clad brazing material of the present invention has a five-layer structure consisting of a copper layer-nickel layer-steel layer-nickel layer-copper layer, when an oil cooler is formed, Even if the directionality of the arrangement of the clad brazing material is not taken into consideration, the nickel layers joined to both sides of the clad plate are always arranged on the water flow path side, and the water corrosion resistance of the oil cooler can be maintained. Further, cost can be reduced by mainly using inexpensive steel and reducing the amount of expensive metal layers having corrosion resistance such as stainless steel and nickel used.

In the above embodiment, the metal bonded to both sides of the steel layer was nickel, but a nickel alloy (for example, N
The same effect can be obtained with i-30% Cu), stainless steel, chromium, and chromium alloys. As a method for coating the clad brazing material, a clad by rolling pressure welding, a plating method, thermal spraying, etc. can be applied.

[0018]

As described above, according to the clad brazing material of the present invention, both sides of a clad plate composed of a steel layer and a water-corrosion resistant metal layer of stainless steel, nickel or the like joined to both sides of the steel layer. Further, since the copper layer as the brazing material is joined, the cost can be reduced without lowering the water corrosion resistance of the oil cooler.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of an oil cooler formed according to the present invention.

FIG. 3 is a sectional view showing the structure of a general oil cooler.

FIG. 4 is an explanatory view showing a conventional clad brazing material.

FIG. 5 is a partial sectional view of an oil cooler formed by a conventional clad brazing material.

[Explanation of symbols]

1 case 2
Fin 3 Oil flow path 4
Water channel 5 Junction 6
Copper layer 7 Stainless layer 8
Clad brazing material 9 Steel layer 10
Nickel layer 11 Clad brazing material 12
Clad plate

Front Page Continuation (72) Inventor Mitsuaki Onuki, 3-1-1 Sukegawa-cho, Hitachi-shi, Ibaraki Hitachi Cable Ltd. Ibaraki Branch

Claims (1)

[Claims] 1. A clad brazing filler metal forming an oil cooler for cooling oil flowing in an oil flow passage by water flowing in a water flow passage, wherein a steel layer and stainless steel joined to both sides of the steel layer,
A clad brazing material comprising a clad plate made of a metal layer having water corrosion resistance such as nickel, and a copper layer as a brazing material bonded to both sides of the clad plate.