JPH07100527A - Corrosion resistant metal covered steel tube - Google Patents

Abstract

PURPOSE:To prolong the life and also to reduce manufacturing cost by forming a covered steel tube by directly winding a thin sheet of a corrosion resistant metal around a steel tube. CONSTITUTION:The coverd steel tube is composed by spirally winding the corrosion resistant metal sheet 2 around the steel tube 1 while pulling the sheet and overlapping edges in the longitudinal direction of a belt-like metal or by winding while butting the edges and mutually joining the edges in the longitudinal direction. In this way, regardless of the large diameter or small diameter of the steel tube, there are such effects as covering with the corrosion resistant metal is easily secured and the life of the steel tube is prolonged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal-coated steel pipe pile having excellent corrosion resistance and a corrosion-resistant metal-coated steel pipe for a pipeline.

[0002]

2. Description of the Related Art Heretofore, there are some anticorrosion steel pipe piles used in the ocean, for example, which are painted or subjected to heavy corrosion protection of polyethylene or urethane. However, the corrosion resistance of these steel pipe piles is limited, and the life is 15 to 20 years in the case of painting and 40 years in heavy corrosion protection.

Further, there is a steel pipe pile using stainless steel or clad steel in order to enhance the corrosion resistance of the corrosion-proof steel pipe pile. In the case of this steel pipe pile, the initial cost is high.

Therefore, as a corrosion-resistant steel pipe pile, Japanese Patent Laid-Open No. 2-2
As disclosed in Japanese Patent No. 56713, there has been devised a steel pipe pile in which the outer surface is coated with an adhesive resin having corrosion resistance and elasticity, and further coated with a corrosion-resistant metal thin plate having embossed irregularities. However, in the case of this anticorrosion steel pipe pile, it is necessary to prepare a corrosion resistant metal corresponding to the diameter of the steel pipe to be coated and the coating length, and the productivity in manufacturing is not high. Further, when coating a large-diameter and long steel pipe, a joint portion of the coated corrosion-resistant metal in the circumferential direction of the steel pipe occurs, which makes efficient coating difficult. Further, water may enter from the closed portion of the corrosion resistant metal, or the closed portion may be opened by an external force such as collision of driftwood, so that the durability of the corrosion resistant metal is not utilized.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a corrosion-resistant metal thin plate-coated steel pipe capable of efficiently and inexpensively coating a steel pipe with a corrosion-resistant metal thin plate and continuously joining the steel pipe.

[0006]

The present invention has solved the above-mentioned problems, and its gist is as follows.

(1) A corrosion-resistant metal-coated steel pipe, characterized in that the edges of a corrosion-resistant metal plate spirally wound in a state in which a tightening force acts on the steel pipe are joined together. (2) The corrosion-resistant metal-coated steel pipe according to the item (1), wherein the joining is adhesion by an adhesive resin or welding by welding. (3) The corrosion-resistant metal-coated steel pipe according to the item (2), wherein the steel pipe is coated with an adhesive resin in advance. (4) The corrosion-resistant metal-coated steel pipe according to item (2), wherein the steel pipe is formed by sequentially laminating chromate, an adhesive primer, an adhesive polyolefin, and a polyolefin resin in advance. (5) The corrosion-resistant metal-coated steel pipe according to the item (2), wherein the steel pipe is preliminarily laminated with an adhesive primer and a urethane resin.

[0008]

In the present invention, the corrosion-resistant metal plate is a stainless steel plate, titanium or titanium alloy plate, according to the life of the steel pipe.
Aluminum or aluminum alloy plate, hot-dip zinc or zinc alloy plated plate, clad plate, etc. are used. The plate is preferably strip-shaped (coil-shaped).

When the above corrosion-resistant metal plate is coated on the steel pipe, if the corrosion-resistant metal plate is wound in a spiral shape while being pulled, a force for tightening the steel pipe acts on the corrosion-resistant metal plate after winding and the corrosion-resistant metal plate and the steel pipe are Integration (adhesion)
Is planned.

As a method of pulling the corrosion-resistant metal plate, for example, as shown in FIG. 2, a coil 5 of corrosion-resistant metal 2 is used,
Tighten with the wrapping roll 4 as shown. Alternatively, a method such as adjusting the rotation speed of the steel pipe 1 and the traveling speed of the corrosion-resistant metal can be applied. In the figure, 3 is a rotating roll, 6 is a welder, and 7 is a joint (weld).

Next, when spirally winding the corrosion-resistant metal plate, the edges of the metal plates are overlapped with each other, or the ends are butted and joined. As a method of joining the end portions of the metal plates, there is a method of applying an adhesive resin 8 to the end portions as shown in FIG. 4 and overlapping and adhering the end portions, or a method of welding by welding as shown in FIG. Adopt it. 7 in the figure
Indicates a welded joint. The welding method is effective when a high joining force is required, such as when the corrosion-resistant metal plate 2 is thick or when the return deformation after winding is large. If necessary, the end portions of the corrosion-resistant metal plate 2 wound around the steel pipe 1 may be welded to the steel pipe 1 by welding, and then the ends of the corrosion-resistant metal plate wound around may be overlapped or welded together. Alternatively, as shown in FIG. 5, even the steel pipe 1 may be welded in a state where the corrosion-resistant metal plates 2 are overlapped. As welding means, welding by electric energy such as arc welding or resistance welding, welding by chemical energy such as gas welding, and welding by light energy typified by laser welding can be used.

Alternatively, in order to integrate the corrosion-resistant metal plate and the steel pipe, as shown in FIG. 6, the steel pipe 1 is derusted and then coated with an adhesive resin 8, and then the corrosion-resistant metal plate 2 is spirally formed. It may also be coated in the form of a circle. This method can be used for a structure or the like in which a larger deformation occurs.

Further, as illustrated in FIG. 7, chromate, an adhesive primer, an adhesive polyolefin, and a polyolefin resin are sequentially laminated between the corrosion-resistant metal 2 and the steel pipe 1 to be coated, or an adhesive primer and a urethane resin are laminated. By sequentially laminating the laminated materials 9 to form the anticorrosion layer, the anticorrosion function can be secured even when the coated anticorrosion metal is broken, and a more reliable anticorrosion steel pipe can be obtained.

[0014]

EXAMPLE FIG. 1 is a view showing an example of an embodiment of the corrosion-resistant metal-coated steel pipe of the present invention, in which the ends of the corrosion-resistant metal plate 2 are overlapped. FIG. 2 shows an explanatory view of a method for producing this corrosion-resistant metal-coated steel pipe.

The corrosion-resistant metal plate 2 is wound around a coil 5 with stainless steel having a width of 1000 mm and a thickness of 1 mm.
Has a diameter of 600 mm and a thickness of 14 mm. While rotating the steel pipe 1 by the rotating roll 3, the metal plate is wound in a spiral shape. At that time, the metal plate 3 is wound while being pulled between the steel pipe and the coil through the winding roll 4 with a tensile force of 10 kg / cm ² or more, and the overlapping portion is welded by the welding machine 6. A cross section of the welded portion is shown in FIG.

By thus spirally winding the coiled corrosion-resistant metal plate 2, the line of the apparatus can be realized, the cost can be reduced, and the quality can be improved.

FIGS. 4, 5, 6, and 7 are partial cross-sectional schematic views of a corrosion-resistant metal-coated steel pipe according to another embodiment of the present invention.

[0018]

The corrosion-resistant metal-coated steel pipe of the present invention can be expected to have the same corrosion resistance as that of the corrosion-resistant metal steel pipe since the steel pipe is surely coated with the corrosion-resistant metal plate.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a corrosion-resistant metal-coated steel pipe according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing an example of a method for producing a corrosion-resistant metal-coated steel pipe of the present invention.

FIG. 3 is a schematic view of a cross section of a joint portion when the ends of a corrosion-resistant metal plate are welded.

FIG. 4 is a schematic view of a cross section of a joint portion when an end portion of a corrosion-resistant metal plate is adhered with an adhesive resin.

FIG. 5 is a schematic view of a cross section of a welded portion when a superposed portion of a corrosion resistant metal plate and a steel pipe are welded.

FIG. 6 is a schematic view of a cross section of a welded portion when a fusible resin is laminated between a corrosion-resistant metal plate and a steel pipe.

FIG. 7 is a schematic view of a cross section of a welded portion when a laminated material is applied between a corrosion resistant metal plate and a steel pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Steel pipe 2 ... Corrosion-resistant metal plate 3 ... Rotating roll 4 ... Winding roll 5 ... Coil 6 Welding machine 7 ... Welding joint 8 ... Adhesive resin material 9 ... Laminated material

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinichi Funazu 1 Kimitsu, Kimitsu City Nippon Steel Corporation Kimitsu Steel Works

Claims (5)

[Claims] 1. A corrosion-resistant metal-coated steel pipe, characterized in that the steel pipe is formed by joining edges of a corrosion-resistant metal plate spirally wound in a state in which a tightening force acts on the steel pipe. 2. The corrosion-resistant metal-coated steel pipe according to claim 1, wherein the joining is adhesion by an adhesive resin or welding by welding. 3. The corrosion-resistant metal-coated steel pipe according to claim 2, wherein the steel pipe is coated with an adhesive resin in advance. 4. The corrosion-resistant metal-coated steel pipe according to claim 2, wherein the steel pipe is preliminarily laminated with chromate, an adhesive primer, an adhesive polyolefin, and a polyolefin resin. 5. The corrosion-resistant metal-coated steel pipe according to claim 2, wherein the steel pipe is preliminarily laminated with an adhesive primer and a urethane resin.