JPH0239352B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for producing tube-on-sheets having excellent corrosion resistance and used for solar heat collection plates for solar water heaters, heat sinks for floor heating, and the like.

Prior art and its problems Conventionally, the tube-on-sheet described above prepares a copper tube and an aluminum sheet, and forms a zinc coating layer on the outer peripheral surface of the copper tube and at least one side of the aluminum sheet in advance, Arranging the required number of copper tubes on the surface of the zinc coating layer of the aluminum sheet, heating at least the portions of the zinc coating layer that are in contact with each other, and when this melts, applying external pressure to press the copper tubes against the aluminum sheet, It was manufactured by cooling and solidifying the molten zinc (see Japanese Patent Publication No. 53-30093).

However, in the tube-on-sheet manufactured in this way, the copper tube 21 and the aluminum sheet 22 are separated as shown in FIG.
Since there is a zinc layer 23 between the tube 2 and the tube 2, if this zinc layer 23 is sacrificially corroded, the tube 2
There is a gap between 1 and the sheet 22, and both 21,
There was a problem that the heat conductivity between the tubes 21 and the sheets 22 deteriorated, or the tubes 21 and the sheets 22 separated from each other.

SUMMARY OF THE INVENTION An object of the present invention is to provide a tube-on-sheet manufacturing method that solves the above problems.

Means for Solving the Problems In the tube-on-sheet manufacturing method according to the present invention, an outwardly protruding portion having a chevron-shaped cross section is provided over the entire length of a part of the peripheral wall of the metal tube, and A sacrificial corrosion layer for the tube is formed on at least one of the outer peripheral surface and the tube joint surface of the metal sheet, and the outward protruding portion of the tube and the portion of the sheet to be joined to the tube, as well as both The sacrificial corrosion layer covering at least one of the parts is heated by high-frequency resistance heating, and then external pressure is applied to press them together, and the outwardly protruding part pushes away the sacrificial corrosion layer and connects it to the tip of the outwardly protruding part of the tube. It is characterized by metallurgically joining the sheets.

In the above, combinations of metals forming the tube and the sheet include aluminum (including aluminum alloys; the same applies hereinafter), aluminum and copper, copper and aluminum, and the like.
The sacrificial corrosion layer is made of A7072 alloy, zinc, etc. The sacrificial corrosion layer may be formed after the tube or sheet is manufactured, or it may be formed at the same time as the tube or sheet is manufactured. In the latter case, the sacrificial corrosion layer is specifically the skin of the clad tube or sheet. The pressure with which the tube and sheet are pressed together is such that the sacrificial corrosion layer at the pressurized portion of the tube and sheet is pushed away and the tube and sheet are directly metallurgically joined.

Example First, a sacrificial corrosion layer 2 made of A7072 alloy is formed on the outer peripheral surface of a tube 1 made of A3003 alloy with a circular cross section, and a sacrificial corrosion layer 2 made of A7072 alloy is formed on one side of a sheet 4 made of A3003 alloy. Layer 5 is formed in advance. The tube 1 with the sacrificial corrosion layer 2 is a clad tube 3 in which the tube 1 is the core material and the sacrificial corrosion layer 2 is the skin material. The sheet 4 with the sacrificial corrosion layer 5 is a clad sheet 6 in which the sheet 4 is a core material and the sacrificial corrosion layer 5 is a skin material.
And on a part of the surrounding wall of Clad Tube 3,
An outwardly protruding portion having a chevron-shaped cross section is provided over the entire length. The outwardly projecting portion of the cladding tube 3, which has a chevron-shaped cross section, is designated by 3a, and the outwardly projecting portion of the tube 1, which has a chevron-shaped cross section, is designated by 1a (see FIG. 3). The opening angle of the tips of the outwardly projecting portions 1a, 3a is preferably about 98 to 105 degrees.

Next, the cladding sheet 6 is applied to the sacrificial corrosion layer 5.
It is wound around the rotatable first roll 10 so that it faces outward, and is made to pass around the first roll 10 in the direction shown by arrow A in FIG. Also,
The clad tube 3 is arranged to move from left to right on a tangent to the first roll 10, as shown by arrow B in FIG. 1, with the outwardly protruding portion 3a facing downward. Above the first roll 10, there is a second roll 11 whose rotating shaft 11a is located in the same vertical plane as the rotating shaft 10a of the first roll 10 and parallel to the rotating shaft 10a.
is located. On the circumferential surface of the second roll 11,
An annular groove 13 with a semicircular cross section is formed around the entire circumference, and a cladding
Approximately the upper half of the tube 3 is inserted therein (see Fig. 2). Then, when the cladding tube 3 passes between the first roll 10 and the second roll 11, the cladding tube 3 and the cladding sheet 6 are brought into contact with each other with the tip of the outwardly protruding portion 3a in contact with the cladding sheet 6. The sheets 6 are pressed against each other. Contacts 14 and 15 that slidably contact the tube 3 and the sheet 6 are provided near the portion where the clad tube 3 and the clad sheet 6 are pressed against each other. The contacts 14 and 15 are connected to a high frequency power source (not shown).

Then, tube 3 and sheet 6 are moved 80m/
A high frequency current of 450 KHz is applied to the contacts 14 and 15 while feeding at a speed of 10 min to cause sacrificial corrosion of the outwardly protruding portion 1a of the tube 1, the portion of the sheet 4 to be joined to the tube 1, and the sacrificial corrosion covering both portions. After heating layers 2 and 5, they were pressed together by first and second rolls 10 and 11.
Then, the sacrificial corrosion layers 2 and 5 are melted and pushed away from between the tube 1 and the sheet 4 by the outwardly protruding portion 1a, and the tip of the outwardly protruding portion 1a of the tube 1 and the sheet 4 are directly metallurgically connected. A tube-on-sheet 16 was continuously obtained in which the tube-on-sheet 16 was bonded to the substrate and the other portions of both were covered with the sacrificial corrosion layers 2 and 5.

In the above embodiments, a clad tube and a clad sheet are used, but the invention is not limited thereto. Furthermore, in the above embodiments, since tube-on-sheets are manufactured continuously, long tube-on-sheets can also be easily manufactured, but the invention is not limited to this. Furthermore, in the above embodiment, the sacrificial corrosion layer is formed on both the outer peripheral surface of the metal tube and the tube joint surface of the metal sheet, but the sacrificial corrosion layer can be formed on either one. good.

Effects of the Invention According to the present invention, the tube and the sheet are directly metallurgically joined without intervening a sacrificial corrosion layer between the two, so the sacrificial corrosion can be achieved by using the obtained tube-on-sheet. Even if the target corrosion layer is corroded, the heat transfer between the tube and the sheet is prevented from being impaired or the two are prevented from peeling off. In addition, an outward protruding portion having a chevron-shaped cross section is provided over the entire length of a part of the peripheral wall of the metal tube, and the outward protruding portion of the tube, the portion of the sheet to be joined to the tube, and at least one of both portions are provided. The sacrificial corrosion layer covering either side is heated by high-frequency resistance heating, and then external pressure is applied to press them together, and the outward protrusion part pushes away the sacrificial corrosion layer to metallurgize the tip of the outward protrusion part of the tube and the sheet. Therefore, only the sacrificial corrosion layer that exists between the parts of the tube and sheet that are to be joined to each other is melted and pushed away, and the sacrificial corrosion layer is removed from the other parts of the resulting tube-on-sheet. has a sacrificial corrosion layer, and has excellent electrochemical corrosion resistance. Moreover, the tube and the sheet are completely and firmly joined.

[Brief explanation of drawings]

FIG. 1 is a side view showing the method of the present invention, FIG. 2 is a cross-sectional view taken along the - line in FIG. 1, and FIG. 3 is a cross-sectional view of the tube and sheet before joining.
FIG. 4 is a cross-sectional view of a tube-on-sheet manufactured by the method of the present invention, and FIG. 5 is a cross-sectional view of a tube-on-sheet manufactured by a conventional method. DESCRIPTION OF SYMBOLS 1...Metal tube, 1a...Outward protrusion part, 2, 5...Sacrificial corrosion layer, 4...Metal sheet.

Claims (1)

[Claims] 1 A part of the peripheral wall of the metal tube is provided with an outwardly projecting part with a chevron-shaped cross section over the entire length,
A sacrificial corrosion layer for the tube is formed on at least one of the outer peripheral surface of the metal tube and the tube joint surface of the metal sheet, and the outwardly protruding portion of the tube and the portion of the sheet to be joined to the tube are formed. , and the sacrificial corrosion layer covering at least one of both parts is heated by high-frequency resistance heating, and then external pressure is applied to press them together, and the outwardly protruding part pushes away the sacrificial corrosion layer to cause the tube to protrude outward. A method for manufacturing a tube-on-sheet, characterized by metallurgically joining a partial tip and a sheet.