JPH06114571A - Production of clad pipe - Google Patents

Abstract

PURPOSE:To produce the clad pipe which is less thermally affected compairing with a welding method and brazing method and has the excellent corrosion resistance and mechanical characteristics of a joined part and the characteristics uniform in a circumferential direction. CONSTITUTION:The clad pipe is produced by forming two kinds of clad blank materials 5, 6 consisting of band-shaped metallic plates to a tubular form, superposing the margins for joining provided on the respective band-shaped metallic plates 5, 6 on each other and joining the superposed parts to form the joined part 8 by cold press welding making combination use of ultrasonic waves.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a clad pipe.

[0002]

2. Description of the Related Art FIG. 8 shows a cross section of a clad pipe manufactured by a butt welding method used as a conventional technique. In FIG. 8, 1 is a butt welded portion, and 7 is a two-layer clad material. First, the strip-shaped dissimilar metal plate is, for example,
It is manufactured by forming a two-layer clad material 7 by cold pressure welding, forming the two-layer clad material 7 into a tubular shape, and welding a butt portion.

FIG. 9 shows a cross section of a clad pipe manufactured by a brazing method used in the prior art. In FIG. 9, 2 and 3 are brazing filler metals, 4 is a brazing filler metal 2 coated with Cu or Sn plating on the surface F
It is a clad material composed of a strip-shaped metal plate of e. The clad material 4 is formed into a tubular shape, and the abutting portion and the overlapping portion are brazed by melting the brazing material. In addition to this, there is a method of forming a cylindrical composite billet and extruding it, or a method of forming a base material of a clad pipe having a large diameter and pulling it out.

[0004]

In such a conventional method, in the clad pipe manufactured by butt welding, only the butt weld portion 1 is locally heated, so that the corrosion resistance and the mechanical strength are deteriorated or deteriorated. There's a problem.

Further, the clad pipe manufactured by extrusion and drawing has a drawback that the long pipe has poor productivity and is expensive in terms of cost.

An object of the present invention is to provide a method for producing a clad pipe which has excellent corrosion resistance and mechanical strength at the joint and can be produced efficiently at low cost.

[0007]

In order to achieve the above object, the method for producing a clad pipe according to the present invention comprises a first strip metal plate and a second strip metal plate which are made of different metals and have substantially the same width. By shifting the required length in the width direction and performing cold pressure welding, a clad material having a joint margin made of the first strip-shaped metal plate and a joint margin made of the second strip-shaped metal plate at both ends thereof is formed. By overlapping the joining margin made of the first strip-shaped metal plate and the joining margin made of the second strip-shaped metal plate by forming the material into a tubular shape, the overlapping portion is subjected to cold pressure welding using ultrasonic waves together. Characterized by joining.

[0008]

According to the method for producing a clad pipe of the present invention, two kinds of clad materials made of strip-shaped metal plates are formed into a tubular shape so that the joining margins provided on the strip-shaped metal plates are overlapped with each other. Since the parts are joined by cold pressure welding that also uses ultrasonic waves, there is less thermal influence compared to the welding method and brazing method, the corrosion resistance and mechanical properties of the joint are excellent, and uniform properties in the circumferential direction are obtained. It is possible to produce a clad pipe with a low cost.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a sectional view of an essential part of a roll forming machine used in an embodiment of the method for producing a clad pipe of the present invention, FIG. 2 is an explanatory view of the roll forming machine, and FIG. 3 shows a clad material as a raw material. The perspective view shown, FIG. 4 is a cross-sectional view of the manufactured clad pipe, and FIG. 5 is an explanatory view of the work roll used. In these figures, 5 is a first strip-shaped metal plate, 6 is a second strip-shaped metal plate, 8 is a joint portion, 9 is a two-layer work roll, 12 is a forming roll, 13 is a rolling down device,
14 is a reduction device housing, 15 is an internal roll stand,
16 is a work roll for reduction, 17 is an internal work roll, 1
8 is a backup roll, 19 is a support roll, 20
Is an ultrasonic generator. The roll forming machine is roughly divided into a forming roll 12, a rolling down device 13, and an internal roll stand 15. The rolling-down device 13 is a rolling-down work roll 16 that is grooved according to the outer shape of the circular pipe, and an internal work roll 1 that presses the joint portion 8 inside the circular pipe.
7. Support rolls that support the internal work rolls 17.

In this manufacturing method, a dissimilar metal plate (Cu plate)
5. A dissimilar metal plate (SUS plate) 6 is displaced by a required length and cold rolled by pressure welding with a deformed roll to produce a two-layer clad material 7.

At this time, the two-layer work roll 9 used for the rolling pressure welding is a roll having one end protruding, and when the roll is set on the rolling mill, it is set so that the protruding portion is rotationally symmetrical. The two-layer clad material 7 obtained as a material is formed into a circular shape by the roll forming machine shown in FIG. The joining portion 8 is joined by ultrasonic waves emitted from the ultrasonic wave generator 20 while performing reduction by the work roll 16 and the inner work roll 17. Cu inside the clad pipe,
Since the outside is made of a SUS plate, the inside has excellent thermal conductivity or electrical conductivity, and the outside has corrosion resistance and the appearance is beautiful. Also, the clad material 4 used for the clad pipe
Since it is manufactured from a long coil, a long coil can be produced at low cost even after being molded into a clad pipe.

In the embodiment, the clad pipes of different metals of Cu and SUS have been described, but various clad materials can be combined, and the following can be considered. That is, a clad pipe having Cu on the inner side and Fe on the outer side can be used for drainage due to the sterilization property of Cu, and a clad pipe having SUS on the inner side and Al as the outer side can be used as an electric wire due to the conductivity of Al and the strength of SUS.

FIGS. 6 and 7 show, as another embodiment of the present invention, a clad pipe manufactured by a method of manufacturing a clad pipe made of three kinds of dissimilar metals such as SUS, Fe and Al and a deformed roll to be used. Also, 10 is a three-layer clad material, and 11 is a three-layer roll, and similar actions and effects can be obtained in this method as well.

[0015]

EFFECTS OF THE INVENTION According to the present invention, a clad pipe having less thermal influence as compared with the welding method and the brazing method, excellent corrosion resistance and mechanical characteristics of the joint, and having uniform characteristics in the circumferential direction is obtained. It can be produced at low cost.

[Brief description of drawings]

FIG. 1 is a sectional view of a main part of a roll forming machine used in an embodiment of a method for manufacturing a clad pipe according to the present invention.

FIG. 2 is an explanatory view of a roll forming machine.

FIG. 3 is a perspective view showing a clad material that is also a material.

FIG. 4 is a sectional view of a clad pipe manufactured in the same manner.

FIG. 5 is an explanatory diagram of a work roll that is also used.

FIG. 6 is a cross-sectional view of a clad pipe manufactured by a method according to another embodiment of the present invention.

FIG. 7 is an explanatory view of a work roll which is also used in another embodiment.

FIG. 8 is a cross-sectional view of a clad pipe manufactured by a method of butt welding according to the related art.

FIG. 9 is a cross-sectional view of a clad pipe manufactured by a conventional brazing method.

[Explanation of symbols]

 7 Double-layer clad material 16 Rolling work roll 17 Internal work roll 18 Backup roll 19 Support roll 20 Ultrasonic generator

Claims (1)

[Claims] 1. A first strip-shaped metal plate and a second strip-shaped metal plate, which are made of different kinds of metals and have substantially the same width, are displaced by a required length in the width direction and are cold-pressed to each other so that the first strip-shaped metal plate is welded to both ends thereof. And a joining margin made of the first strip-shaped metal plate by forming a clad material having a joining margin made of the strip-shaped metal plate and a joining margin made of the second strip-shaped metal plate, and forming the clad material into a tubular shape. A method for producing a clad pipe, characterized in that the joining margins made of the second strip-shaped metal plates are overlapped and the overlapped portions are joined by cold pressure welding together with ultrasonic waves.