JPS61165271A - Clad steel pipe - Google Patents

Abstract

PURPOSE:To decrease the amt. of costly stainless steel to be used for a corrosion- and heat-resistant metallic pipe and to reduce the cost thereof by coupling and cladding a stainless steel plate on the surface of an iron base plate on which a copper layer is deposited, forming the plate to a tubular shape and welding the same. CONSTITUTION:Copper is plated on one or both surfaces of the iron base plate 2 and the stainless steel foil 4 is superposed on the plated surface. The plate and foil are welded in a furnace kept at the m.p. higher than the m.p. of copper to constitute a clad plate. The clad plate is bent, formed and welded to form a clad steel pipe. The inside or outside surface or both surfaces of the steel pipe are made of the stainless steel so as to be made resistant to corrosion and heat. The amt. of the costly stainless steel to be used is decreased and the cost is reduced.

Description

[Detailed description of the invention] a. Field of use in industry The present invention relates to clad steel pipes.

b. Conventional technology Conventionally, for example, hydraulic pipes, pneumatic pipes, etc. for fuel systems, brake systems, and exhaust systems installed in automobiles have been coated with galvanized or solder plated steel pipes on their inner or outer surfaces. This plating layer prevents corrosion of the pipe.

C1 Problems to be Solved by the Invention However, since the coating layer of such conventional cladding tubes is galvanized or solder plated, it has poor corrosion resistance and heat resistance, and is particularly difficult to use when exposed outside the vehicle body. Corrosion resistance under such environments was lacking. In addition, the coating layer is easily damaged by post-processes such as bending the tube, and the scratches may further reduce corrosion resistance. Moreover, the plating solution and pickling solution used in the metallization process remained inside the pipe, causing rust.

The present invention has been made in order to solve the problems of the prior art described in Section 2. The method consists in forming a tube material by joining each other via a tube, and then forming the tube material into a tube shape to form a tube body.

d8 Means to solve problems Hereinafter, the present invention will be explained in detail based on illustrated embodiments.

FIG. 1 shows a first embodiment of the present invention.
In the clad steel pipe 1 shown in FIG. 1A, a copper layer 3 is provided on the outer circumferential surface of an annular iron substrate 2, and a stainless steel foil 4 is provided on the outer circumferential surface of the copper layer 3. In addition, the clad steel pipe l shown in FIG. 1(B) has a copper layer 3 provided on the inner circumferential surface of an iron substrate 2 configured in an annular shape, and a stainless steel foil 4 provided on the inner circumferential surface of the copper N3. It is being In addition, 5 is both side end surfaces which become welding surfaces, and 6 is a bead formed during welding.

The method for manufacturing the clad steel pipe 1 having the above configuration is as follows.

First, as shown in FIG. 2(A), a strip-shaped iron substrate 2, on which one side has been copper-plated in advance and a copper layer 3 attached thereto, and a stainless steel foil 4 are placed on top of each other, and then spot welded with adhesive. etc., and place this in a furnace above the melting point of copper (110
As shown in FIG. 2(B), the iron substrate 2 and the stainless steel foil 4 are heated and bonded using the copper layer 3 as a brazing layer, and the steel substrate 2 and the stainless steel foil 4 are heated to a temperature range of 0 to 1150°C. Form a throat steel strip. Next, this clad steel strip was prepared as shown in Fig. 1 (
In the clad steel pipe 1 of A), the stainless steel foil 4 is arranged on the outer peripheral surface, and in the clad steel pipe 1 of FIG. 1(B), the stainless steel foil 4 is arranged on the inner peripheral surface. The clad steel pipe 1 is manufactured by winding the pipe in the middle direction so that the pipe is wound in the middle direction and joining the end faces 5 on both sides by electric resistance welding, high frequency welding, or the like.

In this embodiment, for example, a crane crane 1 with a finished pipe diameter of 10φ is used.
'When manufacturing the steel pipe 1, the thickness is reduced to 3 by plating.
Thickness 0.8 m++ with deposited copper layer 3 of pm, r113
Iron substrate 2 with a length of 2 mm and a length of 200 m and a thickness of 40 pm.
132, using a stainless steel foil 4 with a length of 200 m, and connecting the iron substrate 2 and the stainless steel foil 4 through the melted copper N3 under the conditions of a heating temperature of 1120°C and a heating time of 20 minutes ± 5 minutes. are combined and further cooled for 10 minutes±3 minutes using a water-cooled jacket cooling method to form a clad steel strip.

FIG. 3 shows a second embodiment of the present invention.
The clad steel pipe 1 shown in FIG. 1(A) has a structure similar to that of the first embodiment shown in FIG. 1(A) but with double concentric winding. Further, the clad steel pipe 1 shown in FIG. 3(B) has a first
This embodiment has the same structure as the first embodiment shown in Figure (B) but has a double concentric winding. In these double-wound clad steel pipes 1, both ends of an iron substrate 2a of the inner tube portion and an iron substrate 2h of the outer tube portion are joined via a central inclined portion 7.

The method for manufacturing the double-wound clad steel pipe 1 having the above structure is as follows.

First, as shown in FIG. 4, a strip-shaped iron substrate 2 with copper plating applied on both sides and a copper layer 3 deposited thereon is installed L-1,
A stainless steel foil 4 is soldered onto one surface of the iron substrate 2 in the same manner as in the first embodiment to form a clad steel strip. Next, this clad steel strip is placed so that the stainless steel foil 4 is arranged on the outer circumferential surface of the clad steel pipe 1 shown in FIG. 3(A), and the clad steel strip 1 of FIG. 3(B) is are arranged on the inner circumferential surface by turning tS in a double concentric circle in the middle direction, and abutting both ends through the central inclined part 7, so that the outer circumferential surface of the iron substrate 2a of the inner tube part and the outer tube part The inner peripheral surfaces of the iron substrate 2h are pressed together, and then,
The double-wound clad steel pipe 1 is manufactured by brazing and joining these inner and outer surfaces with the molten copper layer 3.

According to the double-wound clad steel pipe 1 of this embodiment, corrosion resistance and heat resistance can be further improved compared to a double-wound clad steel pipe.

Although the embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications and changes can be made based on the technical idea of the present invention.

e0 Effects of the Invention As shown in the double series, the clad steel pipe according to the present invention uses a pipe material in which an iron substrate with a copper layer attached to at least one surface and a stainless steel plate are bonded to each other via the copper layer. Since it is molded, a high-performance tube with excellent corrosion resistance and heat resistance can be obtained, and the product cost can be reduced compared to conventional stainless steel tubes. In addition, even if the clad steel pipe of the present invention is a small-diameter pipe, it is possible to easily cover the inner circumferential surface as well as the outer circumferential surface, and since it is made of stainless steel, it can be easily coated by bending etc. in the post-process. No damage to LJ (no deterioration of corrosion resistance).

Furthermore, in the present invention, since the stainless steel plate is coated on the iron substrate, there is no fear of through holes forming in a steel pipe made of stainless steel, which has pitting corrosion properties.

[Brief explanation of drawings]

Fig. 1 shows a first embodiment of a clad steel pipe according to the present invention, in which Fig. 1 (A) is a cross-sectional view of a clad steel pipe with stainless steel arranged on the outer circumferential surface, and Fig. 1 (B) Figure 2 is a cross-sectional view of a clad steel pipe with stainless steel on the inner surface, Figure 2 is for explaining the manufacturing process of the tube material, and Figure 2 (A) is a cross-sectional view of a clad steel pipe with stainless steel on the inner surface. A vertical cross-sectional view showing the state before brazing, FIG. 2 (B) is a vertical cross-sectional view showing the state after brazing the stainless steel foil to the iron substrate,
FIG. 3 shows a second embodiment of the clad steel pipe according to the present invention, and FIG. 3 (A) is a cross-sectional view of the clad steel pipe in which stainless steel is arranged on the outer circumferential surface and double-wound; Fig. 3 (I3) is a cross-sectional view of a double-wound clad steel pipe with stainless steel arranged on the inner circumferential surface, and Fig. 4 is a cross-sectional view of a clad steel pipe made of double-wound stainless steel. FIG. 2 is a longitudinal cross-sectional view showing the state after brazing stainless steel foil to the holder. 1... Clad steel pipe, 2... Iron substrate, 3...
・lal IN, 4...Stainless steel foil. 71

Claims (1)

[Claims] An iron substrate with a copper layer attached to at least one surface and a stainless steel plate are bonded to each other via the copper layer to form a tube material, and then the tube material is formed into a tube shape to constitute a tube body. A clad steel pipe featuring: