JPH09174153A - Manufacture of welded titanium-clad steel pipe pile for corrosion resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To continuously join while efficiently and surely coating a titanium sheet on a steel pipe by applying a submerged arc welding to a steel sheet to manufacture a spiral steel pipe, winding the titanium sheet into a spiral-state at the slipping position from the steel sheet width on this steel pipe surface and applying a resistance welding to the laminated part. SOLUTION: The steel sheet 1 is formed into a spiral-state and the edge part 1a and the other edge part 1b of the steel coil 1 are butted, and the submerged arc welding 4 is applied to this butted part to manufacture the steel pipe 2. Further, in this manufacturing line, the titanium sheet 3 is disposed at the rear part of the steel coil 1 and wound on the surface of the formed steel pipe 2 and brought into close contact. The welding to mutually the titanium sheets is subjected to an indirect resistance seam welding 5 while superposing the one edge part 3a and the other edge part 3b. The formed titanium coated pipe 6 is laminarily in close contact, thus to manufacture the welded titanium-clad steel pipe 7. Therefore, the steel pipe 2 can continuously by covered with the corrosion resistance metal sheet and the manufacturing efficiency is improved.

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 titanium clad steel pipe pile for corrosion protection, the surface of which is coated with titanium having excellent corrosion resistance, and is particularly used as a marine structure in a splash zone near the surface of seawater. The present invention relates to a method for manufacturing a titanium clad steel pipe pile having high corrosion resistance.

[0002]

2. Description of the Related Art Conventionally, steel pipe piles that have been established in the sea as the basis of offshore structures are subject to a large amount of corrosion of the splash zone washed by seawater. Has been given. However, there is a limit to the corrosion resistance of these steel pipe piles, and the life is said to be 15 to 20 years in the case of painting and 40 years in the case of heavy corrosion prevention.
On the other hand, in order to enhance the corrosion resistance of anticorrosion steel pipe piles, it has been proposed to manufacture the pile body from a clad steel of stainless steel or a corrosion resistant material such as stainless steel and ordinary steel, but such piles have high initial costs, It is a disadvantage.

In order to eliminate such disadvantages, JP-A-2-
Japanese Patent No. 256713 proposes a steel pipe pile subjected to anticorrosion treatment. That is, the outer surface of the steel pipe pile is given a normal coating base, coated with an adhesive resin having corrosion resistance and elasticity on it, and further coated with a corrosion-resistant metal thin plate processed with embossed unevenness, specifically tightening. While being wound, the anticorrosion steel pipe pile in which the thin plate end portion is folded or caulked and fastened is disclosed, but in such a steel pipe pile,
It is necessary to prepare a corrosion-resistant metal thin plate having a width and a length corresponding to the pipe diameter and the coating length of the steel pipe pile to be coated,
Therefore, productivity is not high. Further, when coating a large diameter and long band, a joint portion is formed in the circumferential direction of the steel pipe of the corrosion-resistant metal thin plate to be coated, which makes efficient coating difficult.

On the other hand, Japanese Utility Model Laid-Open Publication No. 62-44948 discloses a method of anticorrosion construction using a titanium plate having excellent corrosion resistance as a thin metal plate to be coated. That is, a sheet-shaped titanium cover main body having a desired width and length, and flanges formed at both ends thereof, an insulating material is interposed between the opposing flanges, and the insulating flange is brought into contact with the flange to prevent corrosion. An anticorrosion cover for existing piles has been proposed that is detachably fixed with metal bolts. On the surface of the structural steel pipe after molding,
When a titanium sheet is made into a large plate and applied for coating, the length of the titanium sheet for covering the titanium sheet in the width direction is insufficient depending on the size of the steel pipe, and the titanium plate length can be wound around the steel pipe. There is a problem in that it is extremely troublesome, for example, a joint for joining a plurality of steel pipes in the circumferential direction of the steel pipe to obtain a steel pipe covered length and a means for fixing the steel pipe and the titanium plate are required. Further, the cover of the existing steel pipe pile is attached in the sea because of the screw structure, and it is necessary to attach it by a diver, which has a drawback that the attachment cost becomes extremely high.

[0005]

Titanium is used to enhance the corrosion resistance of anticorrosion steel pipe piles. For this purpose, in addition to coating the steel pipe with titanium as described above, a pipe using explosive titanium clad steel is used. Pile is proposed. In manufacturing a pipe pile from explosive titanium clad steel, in order to produce the clad steel plate by the UO system and bending system (BR system), the length and size of the pipe pile are determined according to the size of the explosive titanium clad steel plate. Is limited. Further, in such a manufacturing method, since the steel sheet is subjected to a severe bending process, there is a problem that the wavy joint portion at the interface of the explosive-bonded titanium clad steel is loosened and the joint strength is lowered.

The present invention solves the above-mentioned problems, adopts a spiral pipe manufacturing method to simplify the working process, coats a steel pipe pile with a titanium plate efficiently and reliably, and continuously It is an object of the present invention to provide a method for manufacturing a welded titanium clad steel pipe that can be mechanically joined.

[0007]

In order to achieve the above object, the present invention provides a steel strip in a spiral shape in the production of an anticorrosion steel pipe pile in which a titanium plate is wrapped around a steel pipe to cover the steel pipe, and a steel strip width is provided. Butt ends of the direction, and this part is submerged arc welded to form a spiral steel pipe.Titanium strips are spirally wound at a position deviated from the steel strip width on the surface of the steel pipe, and the strip width direction Is set so that the end portions of the overlap, and the resistance welding of this overlapped portion is a method for producing a welded titanium clad steel pipe pile for corrosion protection,
In the production of anti-corrosion steel pipe piles in which a titanium plate is wrapped around a steel pipe, the steel strip is supplied in a spiral shape, the ends in the width direction of the strip are abutted, and this part is submerged arc welded to form a spiral steel pipe. , A titanium strip is wound in a spiral shape while applying a tension of 10 kgf / cm ² or more at a position deviated from the width of the steel strip on the surface of the steel pipe formed on the same line by a tension of 10 kgf / cm ² or more. A method for manufacturing a welded titanium clad steel pipe pile for corrosion protection, characterized in that the end portions are set so as to overlap each other, and the overlapped portion is resistance welded.

In the method for producing a welded titanium clad steel pipe according to the present invention, before winding the titanium strip plate in a spiral shape, the steel strip is made into a spiral shape and the widthwise end portions are butted.
After this butt joint is Fe-Fe submerged arc welding, a strip-shaped titanium plate is wrapped around the steel pipe from the back and indirect resistance seam welding is performed, and Ti-Ti welding is performed by resistance welding. A steel pipe of steel is manufactured. Since the titanium strip is wound after forming the steel pipe with a delay of approximately 1/2 or more of the width of the steel strip, it is possible to perform welding on the same line without welding different metals. A spiral steel tube can be coated with spiral titanium to produce a laminated tube.

Further, in spiral welding, welding of a steel strip precedes that of a titanium strip. Therefore, an electrode of an indirect resistance welding machine is set at the end of the formed steel pipe, and steel-steel (Fe- After the Fe) submerged arc welding is completed, titanium-titanium (Ti-Ti) indirect resistance welding can be performed. Therefore, the transformer of the resistance welding machine and the secondary cable of the power feeding roller are shortened, and the current reduction is small, and good welding can be performed.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a long welded titanium clad steel pipe is continuously manufactured as a spiral pipe in the same line by winding a corrosion resistant metal plate typified by titanium around a structural steel pipe. And steel pipes are integrated.

Fe-Fe welding for forming a steel pipe is preferably performed by using the submerged arc welding method in consideration of the welding efficiency, and welding is performed by selecting welding conditions that reduce the excess as much as possible. In the case where there is a large amount, it is preferable to remove the extra beads with a bead grinder and then perform Ti-Ti indirect resistance welding at a position deviated from the width of the steel strip. Since this resistance welding does not need to consider the formation of compounds due to Ti-Ti welding, stable and high-speed welding can be performed.

[0012] If necessary, in order to protect the steel pipe from the outside as well, in the gap formed between the surface of the steel pipe and the titanium coil, a hardenable filler such as an organic adhesive is formed by perforation provided in the steel pipe. Acrylic-based, epoxy-based, butyl-based, polyethylene-based, vinyl-based synthetic resin or the like is filled as a material to prevent corrosion and protect the gap.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view illustrating an example of a method for manufacturing a welded titanium clad steel pipe. As shown in the figure, a steel strip (coil) 1 is formed into a spiral shape, the edge 1a of the steel coil 1 and the other edge 1b of the steel coil 1 are butted, and the butted portion is subjected to submerged arc welding 4 The steel pipe 2 is manufactured. Further, in this manufacturing line, a titanium strip (coil) 3 is arranged behind the steel coil 1, and the titanium strip 3 is wound around and adhered to the surface of the formed steel pipe 2, so that one end edge of the titanium strip is formed. 3a and other edges are overlapped and titanium-titanium welding is performed by indirect resistance seam welding 5, and the formed titanium-coated pipe 6 is laminated and adhered to produce a welded titanium clad steel pipe 7. In the figure, 8 is a steel strip bending roll, 9 is a titanium strip winding roll, 10 is a boom welder for submerged arc welding, and 11 is an inner submerged arc welding machine.

FIG. 2 is a perspective view showing an example of the welded titanium clad steel pipe 7 manufactured by the apparatus of FIG. 1, FIG. 3 is a sectional view of the steel pipe 2, and 12 shows a steel pipe butt weld.
4 is a sectional view taken along the line AA of FIG. 2, and shows a welded titanium clad steel pipe 7 in which a titanium-coated pipe 6 is laminated and adhered on the surface of the steel pipe 2. Reference numeral 13 is a joint portion of the titanium plate bands.

To manufacture the welded titanium clad steel pipe 6 shown in FIG. 1, a steel strip 1 having a plate width of 1000 to 1200 mm and a thickness of 9 to 25 mm is used, and this is formed into a spiral steel pipe 2 having a diameter of 600 to 2000 mm. For forming the steel pipe 2 of the pipe, the butt surfaces (1a, 1b) of the steel strip 1 are butt-welded by submerged arc welding 4 and 11, and the outer surface is welded by selecting welding conditions in which excess is reduced as much as possible. .

The titanium strip has a thickness of 0.3 mm and a width of 1
000 to 1200 mm is used. After the steel strip 1 is subjected to submerged arc welding, it is set to a spiral shape so that the edges 3a and 3b of the titanium strip plate are overlapped with each other, and the indirect shape is set to the indirect direction. Resistance welding machine 5 welding current 7.2KA,
Lap resistance welding was performed at a pressure of 200 kg and a welding speed of 100 cm / min.

The secondary cable of the transformer and the power feeding roller was shortened, and the current reduction was small so that good welding could be performed.
At this time, the titanium strip is passed through the winding roll 9 and the steel pipe 2
Was applied while applying a tension of 10 kg / cm ² or more between them, and Ti-Ti indirect resistance seam welding was performed on the steel pipe while pressurizing the overlapping portions (titanium strip short edge portions 3a-3b). Since it is indirect resistance seam welding, Fe-Ti welding is not performed, so that compounds such as FeTi + Fe ₂ Ti, Fe ₃ Ti and TiC are not generated, and as shown in FIG. It was welding.

As a result of a tensile test of the titanium seam welded portion, the tensile strength was 150 to 200 kgf / mm ² , and the bonding strength was sufficiently secured. The space between the surface of the steel pipe 2 of the welded clad steel pipe 7 and the titanium-coated pipe 6 was filled with a polyethylene-based synthetic resin as an organic adhesive, among the hardening fillers.

[0019]

As described above, according to the method for producing a welded titanium clad steel pipe of the present invention, the steel pipe can be reliably and continuously coated with the corrosion-resistant metal plate, which greatly contributes to the production efficiency of the metal-coated steel pipe. is there.

[Brief description of the drawings]

1A is an explanatory view of a method for manufacturing a welded titanium clad steel pipe obtained by the present invention, FIG. 1B is a side view of a submerged arc weld, and FIG. 1C is a side view of an indirect resistance seam weld. Is.

FIG. 2 is an explanatory view of a welded titanium clad steel pipe obtained by the present invention.

FIG. 3 is a sectional view of a steel pipe of a welded titanium clad steel pipe obtained by the present invention.

FIG. 4 is a sectional view taken along the line AA of FIG. 2;

FIG. 5 is a sectional view taken along line BB of FIG. 2;

[Explanation of Codes] 1: Steel coil 1a, 1b: Steel coil end 2: Steel pipe 3: Titanium coil 3a, 3b: Titanium coil end 4: Submerged arc welder 5: Indirect resistance seam welder 6: Titanium coating Tube 7: Welded titanium clad steel tube 8: Rotating roll 9: Winding roll 9a, 9b: Winding roll 10: Boom welder 11: Inner surface submerged arc welder 12: Steel pipe butt weld 13: Titanium plate seam weld 14: Chile

Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical indication location // B23K 103: 14 103: 16 (72) Inventor Tadami Adachi 3-5-4 Tsukiji, Chuo-ku, Tokyo Date (72) Inventor Shinji Fukano 3-5-4 Tsukiji, Chuo-ku, Tokyo Inside Nippon Steel Welding Industry Co., Ltd. (72) Inventor Kazumi Matsuoka 20-1 Shintomi Shintomi, Futtsu, Chiba Prefecture (72) Inventor Nobuhiro Goto 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Co., Ltd. Technology Development Division (72) Inventor Hisashi Kanai 2-6-Otemachi, Chiyoda-ku, Tokyo 3 Nippon Steel Corporation (72) Inventor Masayoshi Akasaka 2-6-3 Otemachi, Chiyoda-ku, Tokyo 2-6-3 Nippon Steel Corporation (72) Inventor Yasuo Takahashi 2-6-Otemachi, Chiyoda-ku, Tokyo 3 Nippon Steel Corporation (72) Inventor Kazuhiro Kinoshita 2-6-3 Otemachi, Chiyoda-ku, Tokyo Inside Nippon Steel Corporation

Claims (2)

[Claims] 1. In the production of an anticorrosion steel pipe pile in which a titanium plate is wrapped around a steel pipe to cover the steel pipe, the steel strip is supplied in a spiral shape, the ends in the width direction of the steel strip are abutted, and submerged arc welding is performed to form a spiral steel pipe. Formed, at a position deviated from the steel strip width on the surface of the steel pipe, a titanium strip is spirally wound and set so that the end portions in the strip width direction overlap, and resistance welding of this overlapping portion is performed. A method for manufacturing a welded titanium clad steel pipe pile for corrosion protection. 2. A spiral steel pipe is manufactured by supplying a steel strip in a spiral shape, butt-joining the ends in the width direction of the steel strip and performing submerged arc welding in the production of an anticorrosion steel pipe pile in which a titanium plate is wound around a steel pipe to cover the steel pipe. Formed and wound in a spiral shape while applying a tension of 10 kgf / cm ² or more to a titanium strip at a position that is approximately half the steel strip width on the surface of the steel pipe formed on the same line A method for producing a welded titanium clad steel pipe pile for corrosion protection, characterized in that the piled portions are set so that the end portions in the same direction are overlapped, and the overlapped portions are resistance welded.