JP2008289972A - Rustproof working method for long steel material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a rustproof coated steel twisted wire by which rustproof coating is carried out without causing pin holes, the rustproof treatment is carried out simultaneously with a heat treatment of a steel wire, a steel rod and a steel twisted wire and a gap between single wires in the steel twisted wire, that is, the internal gap of the steel twisted wire, is easily and surely filled. <P>SOLUTION: The long steel material such as the steel wire or the steel rod is subjected to heat treatment such as bluing-and/or heat-stretching-treatment and after that, the long steel material in a heated state by the heat treatment is brought into contact with a powdery synthetic resin coating raw material comprising an ethylene-vinyl acetate copolymer (EVA), an ethylene-vinyl acetate copolymer saponified material (EVOH), an ethylene-methacrylate copolymer (EMAA), an ionomer resin, a thermoplastic resin having a polar group such as ethylene ethyl acrylate or the like or fluororesin, and coated with the coating raw material melted by the heat of the heat treatment of the long steel material on the outer peripheral surface and then cooled to solidify the melted and deposited coating raw material. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention has internal voids used for steel wires, steel rods, which are concrete reinforced steel materials, mainly for stress introduction of prestressed concrete (hereinafter referred to as PC), suspension materials such as cable-stayed bridges, and tension materials for tension strings. The present invention relates to a rust-proofing method for a long steel material that applies a rust-proof coating to a long steel material such as a rust-proof coated steel stranded wire filled with a synthetic resin rust-proof material.

  Conventionally, electrostatic powder coating using a thermosetting resin such as epoxy has been used as a rust-proofing treatment for reinforcing bars, steel bars, PC steel bars, etc., which are concrete reinforced steel materials.

  In addition, the rust-proof coated steel stranded wire used for tension wires for PC wires and string strings has multiple side wires made of single steel wire around the core wire made of single steel wire. , It is twisted by a twisting machine to make a steel stranded wire, or an intermediate layer consisting of a large number of single strands is twisted in one or more layers around the core wire, and it consists of a plurality of single strands on the outside The outer layer wire is twisted to form a steel stranded wire. In the production thereof, after twisting each steel wire, the steel stranded wire is heated to 300 ° C. to 350 ° C. and subjected to a blueing treatment to form a steel stranded wire. Improve the tensile strength, elastic limit, fatigue limit, etc., apply a tensile load while heating the steel stranded wire to about 300 ° C. to 350 ° C., etc., and then cool it (so-called Reduction of relaxation by heat stretching process or hot stretching process) It is.

In the rust-proof coating treatment of this steel stranded wire, the manufactured steel stranded wire is preheated to about 200 ° C. to 300 ° C., and is passed through a crosshead type synthetic resin extrusion molding machine. There is a method in which a gap between single strands is filled with a thermoplastic synthetic resin material and the outer periphery of a steel stranded wire is covered with a synthetic resin material.
JP-A-57-198211 Japanese Patent No. 2537457

  However, in the conventional technology as described above, heat treatment such as heat stretching of a long steel material and rust prevention coating process are performed in different places, so that a product, that is, a steel stranded wire, is transported between both workplaces. There is a problem that it is expensive and causes an increase in the cost of the product. In addition, there is a problem that the steel stranded wire must be subjected to a descale (rust removal) treatment when working.

  In addition, electrostatic powder coating using a thermosetting resin has a problem in that there are many cases where pinholes are large and rust prevention treatment is not sufficient.

  In addition, in the rust prevention treatment of steel stranded wire, since the work of filling the rust prevention material in the gaps between the single strands after twisting, advanced technology is required to obtain a sufficient filling state. In short, there is a problem that the yield of finished products deteriorates and the cost is inevitably high.

  In view of such a conventional problem, the present invention has a rust-proof coating without a pinhole made of a thermoplastic resin, and can be rust-proofed simultaneously with the heat treatment of a steel wire, a steel rod and a steel stranded wire, For stranded wires, the space between single strands, that is, the internal space in the steel stranded wire, can be filled easily and reliably, and the production of rust-proof coated steel stranded wire with good yield and low cost It was made for the purpose of providing a method.

  In order to solve the conventional problems as described above and achieve the initial object, the feature of the invention described in claim 1 is that a long steel material such as a steel wire or a steel bar is subjected to a blueing treatment and / or a heat stretching treatment. After the heat treatment such as the above, the long steel material heated by the heat treatment is subjected to ethylene vinyl acetate copolymer (EVA), ethylene vinyl acetate copolymer saponified product (EVOH), ethylene-methacrylic acid copolymer ( EMAA), ionomer resin, powder synthetic resin coating raw material made of a thermoplastic resin having a polar group such as ethylene ethyl acrylate or fluorine resin, and the coating raw material is heated during the heat treatment of the long steel material. In this case, the coating raw material is solidified after being melted and deposited on the long steel material by being melted and deposited on the outer peripheral surface.

  The feature of the invention described in claim 2 is that, in addition to the configuration of claim 1, the long steel material is a PC steel material.

  The feature of the invention described in claim 3 is that, in addition to the structure of claim 1, the long steel material is a deformed steel bar.

  According to a fourth aspect of the present invention, in addition to the configuration of any one of the first to third aspects, the contact of the powdered synthetic resin coating raw material with the long steel material is performed by a powdered coating raw material by air. The long steel material is continuously passed through the powder coating raw material floating tank in which the material is suspended.

  According to a fifth aspect of the present invention, in addition to the structure of any one of the first to third aspects, the contact of the powdered synthetic resin coating raw material with the long steel material is caused by grounding the long steel material. In addition, it is performed by spraying a powdery coating material charged with static electricity to the surface by electrostatic attraction.

  The invention according to claim 6 is characterized in that a side wire is wound around the outer periphery of the core wire, or one or more layers are twisted around the outer periphery of the core wire, and an outer layer wire is applied outside the middle layer wire to form a steel stranded wire. The steel stranded wire is processed and subjected to a heat treatment such as a blueing treatment and / or a heat stretching treatment, and a gap between each single strand constituting the steel stranded wire is filled with a rust preventive material. In addition, in the rust-proofing method for a long steel material in which the outer periphery of the steel stranded wire is coated with a rust-proofing material, a rust-proofing material comprising a thermoplastic synthetic resin heated and melted at the twisting position at the time of the twisting is supplied. Then, the space between the single strands of the steel stranded wire is filled with the rust preventive material, and then the steel stranded wire is heated by the heat treatment after being subjected to the heat treatment. Ethylene vinyl acetate copolymer (EVA), ethylene vinyl acetate copolymer By contacting a powdered synthetic resin coating raw material made of a thermoplastic resin or a fluororesin having a polar group such as a cyanide (EVOH), an ethylene-methacrylic acid copolymer (EMAA), an ionomer resin, or ethylene ethyl acrylate, The coating raw material is melted by the heat of the long steel material and deposited on the outer peripheral surface, and then cooled to solidify the coating raw material after being melted and deposited on the long steel material.

  As described above, in the present invention, the long steel material such as a steel wire and a steel rod is subjected to heat treatment such as brewing treatment and / or heat stretching treatment, and then the long steel material in a heated state by the heat treatment is used. Thermoplastics having polar groups such as ethylene vinyl acetate copolymer (EVA), saponified ethylene vinyl acetate copolymer (EVOH), ethylene-methacrylic acid copolymer (EMAA), ionomer resin, ethylene ethyl acrylate, etc. By bringing a powdered synthetic resin coating raw material made of resin or fluorine resin into contact, the coating raw material is melted by the heat during the heat treatment of the long steel material and deposited on the outer peripheral surface, and then cooled by the cooling Because the coating raw material is solidified after being melted and deposited on a long steel material, the heat of heat treatment during the manufacture of the steel material is used. Rust-proof coating with resin can be performed without rust removal treatment, and the coating raw material is melted and deposited to the thickness required for rust prevention even when installed on the outer periphery of long steel as bending or PC steel Therefore, a more complete rust prevention treatment can be performed with a high yield.

  Further, the contact of the powdered synthetic resin coating raw material with the long steel material is performed by continuously passing the long steel material through a powder coating raw material floating tank in which the powdered coating raw material is suspended by air. Thus, the resin layer can be efficiently applied to the long steel material after the heat treatment that is continuously fed.

  Furthermore, a rust preventive material made of a thermoplastic synthetic resin heated and melted at a twisting position at the time of twisting of the steel stranded wire is supplied, and the space between the single strands of the steel stranded wire is filled with the rust preventive material. Then, after the heat treatment is applied to the steel stranded wire, the outer periphery of the steel stranded wire is covered with a rust preventive material made of a thermoplastic synthetic resin, thereby processing the steel stranded wire. At the same time, the rust-proofing can be performed, and the gaps between the single strands, that is, the internal gaps in the steel stranded wires can be filled easily and reliably, and the yield can be improved and the production can be performed at low cost.

  Further, each single strand is provided by surrounding the outer periphery of the twisted position of the single strands in the twisting process with a container to which a thermoplastic resin is supplied, and supplying the thermoplastic resin heated and melted in the container. By filling the gap between them with a rust preventive material made of thermoplastic synthetic resin that is heated and melted during the twisting process of the steel stranded wire, the space inside the steel stranded wire can be filled with the rust preventive material easily and accurately. .

  Further, after the heat treatment, while the heated state of the steel stranded wire by the treatment is maintained, the steel stranded wire is passed through a crosshead type synthetic resin extrusion molding machine and the outer periphery thereof is made of a thermoplastic synthetic resin. By coating with a rust material, the heating work as a pretreatment of the conventional coating process becomes unnecessary, and the cost is reduced.

  In addition, after the heat treatment, while the heated state of the steel stranded wire by the heat treatment is maintained, the steel stranded wire is passed through the thermoplastic synthetic resin powder layer to cover the powder around the steel stranded wire. By coating the outer periphery of the steel stranded wire by the powder coating method to be applied, the apparatus for coating is simplified.

  Furthermore, polar groups such as ethylene vinyl acetate copolymer (EVA), ethylene vinyl acetate copolymer saponified product (EVOH), ethylene-methacrylic acid copolymer (EMAA), ionomer resin, ethylene ethyl acrylate and the like as rust preventive materials. By using a powder synthetic resin coating raw material made of a thermoplastic resin or a fluororesin having a good resistance to deformation of the steel stranded wire after solidification of the rust preventive material, it becomes difficult to peel off and work in use Good durability and improved durability.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a schematic configuration of a first embodiment of the present invention, and more specifically, a steel twist in which side wires 2 which are also single strands are aligned around a core wire 1 which is a single strand by a single arrangement. As shown in FIG. 7, a space between the single strands of the steel stranded wire 3 (hereinafter referred to as an internal space) 4 is internally filled and prevented with respect to the wire 3, for example, a seven-stranded steel stranded wire 3 not subjected to normal rust prevention. An overall schematic configuration for producing a rust-proof coated steel stranded wire 7 that is filled with a rust material 5 and whose outer periphery is coated with an external coating rust-proof material 6 is shown.

  The rust preventive material used in this example is an ethylene vinyl acetate copolymer (EVA), an ethylene vinyl acetate copolymer saponified product (EVOH), an ethylene-methacrylic acid copolymer (EMAA) as an outer coating rust preventive material, A powder synthetic resin coating raw material made of a thermoplastic resin having a polar group such as an ionomer resin or ethylene ethyl acrylate or a fluorine resin is used. In addition, polyethylene or the like can also be used as the internal filling anticorrosive material 5.

  In FIG. 1, the code | symbol 10 is a steel wire twist processing machine. This processing machine has a rotating disk 13 that is driven to rotate about a horizontal support shaft 12 of a machine base 11, and a stranded wire reel 14 corresponding to the number of twists is provided on the front surface of the rotating disk 13. The side wire 2 is wound beforehand. Further, a through hole is opened at the center of the rotating disk 13, and the core wire 1 is passed through the central portion thereof. The core wire 1 is wound around a core wire reel 15 in advance. Then, the side wire 2 is spirally twisted around the outer periphery of the core wire 1 by turning the rotating disk 13 while moving the core wire 1 as a center line.

  A heater 17 is fixed to the machine base 11 to heat the center line made of the core wire 1. In addition, this heater 17 should just exist in the position where this core wire is pre-heated in the rear part of the feeding position from the reel 15 of the core wire 11. This preheating is for bonding the internally filled anticorrosive material 5 to each single strand, and is heated to about 200 ° C. As the heater 17, a high-frequency induction heater can be used in addition to a heating wire heater.

  The internally filled anticorrosive material 5 is supplied to the twisting position of the side wire 2 with respect to the core wire 1, and the internal voids in the steel twisted wire are filled with the anticorrosive material 5 simultaneously with the twisting process. That is, the container 20 for supplying a rust preventive material is disposed around the twisting position, and the inner filled rust preventive material 5 heated and melted in the container 20 is pressurized and injected to the twisting position. A rust preventive material is filled, and this is wound into the steel stranded wire 3 when the single strands are twisted together to fill the internal gap.

  As shown in FIG. 2, the container 20 has an inner peripheral surface 21 formed in a taper shape in accordance with the feeding angle of the side line 2, and is heated by resin from a rust preventive material supply port 22 opened on the inner peripheral surface. The rust preventive material 5 heated and melted from the melt extruder 23 is pressurized and injected into the container 20. The container 20 is entirely maintained at a predetermined melting temperature of the resin by the electric heater 29.

  The back surface of the container 20 is closed by a rotating lid body 24, and the lid body 24 has opening ports 25 and 26 through which the core wire 1 and the side wire 2 pass, and at the tapered tapered end portion. A stranded wire passage hole 27 through which the twisted steel stranded wire passes is opened. A die 28 corresponding to the outer peripheral shape of the steel stranded wire 3 is rotatably fitted in the passage hole 27, and most of the internally filled rust preventive material 5 attached to the outer periphery of the steel stranded wire 3 is removed. It is like that.

  As shown in FIG. 6, the steel stranded wire 3 twisted in a state in which the internal space is filled with the rust preventive material 5 is then passed through a brewing furnace 30 which is a heat treatment for removing the processing strain. The residual stress due to twisting is removed. An induction heating furnace can be used as the brewing furnace 30. Although not shown in detail in the drawing, an inductor for passing a high-frequency current is provided therein, and the steel stranded wire 3 passes through the center of the inductor. ing.

  The stranded steel wire 3 that has passed through the brewing furnace 30 is then sent to a heat stretching device 31 that is a heat treatment for reducing relaxation. The heat stretching device 31 includes, as an example, a heating furnace 32 and feed mechanisms 33a and 33b that are provided before and after the heating furnace 32 and apply a predetermined tension to the steel stranded wire 3. The relaxation performance is improved by performing the cooling process.

  The steel stranded wire 3 that has been subjected to the heat stretching treatment is subjected to rust removal on the surface by applying to the descaling device 34 as necessary, and then the steel stranded wire temperature is a temperature required for resin deposition (for example, about 250 ° C.) Before becoming lower, a rust-proof coating is applied to the outer periphery of the steel stranded wire 3. This rust-proof coating treatment is to apply a synthetic resin coating to the outer peripheral surface of the steel stranded wire 3 by using the heating by the heating furnace 32 in the heat stretching treatment. As an example, as shown in FIG. A powder coating device 35 is used.

  This powder coating apparatus 35 has a raw material floating tank 37 for floating a powder synthetic resin coating raw material 36 by air. The raw material floating tank 37 has a bottom plate 38 having a large number of fumaroles on the bottom surface, an air introduction chamber 39 under the bottom plate, and air is introduced from the blower 40 into the air introduction chamber 39.

  In this raw material floating tank 37, long steel material insertion holes 41a and 41b are opened so that the steel stranded wire 3 can be continuously passed through the wall surfaces facing each other at the intermediate height position. In addition, a hopper 37 a for supplying the coating raw material 36 is provided in the upper part of the raw material floating tank 37.

  In the raw material floating tank 37, ethylene vinyl acetate copolymer (EVA), ethylene vinyl acetate copolymer saponified product (EVOH), ethylene-methacrylic acid copolymer (EMAA), ionomer resin, ethylene ethyl acrylate, etc. A coating raw material 36 made of a powdered synthetic resin made of a thermoplastic resin or a fluorine resin having a polar group is accommodated, and the coating raw material 36 is lifted by ejecting air from the air holes of the bottom plate 38. In this state, the steel stranded wire 3 heated by the heat treatment described above is passed through the long steel material insertion holes 41a and 41b. As a result, the floating coating raw material 36 comes into contact with the steel stranded wire 3 and is melted by the heat of the steel stranded wire 3 to adhere to the surface.

  After the outer periphery of the steel stranded wire 3 is thus covered with the externally coated anticorrosive material 6, it is passed through a cooler 42, the whole is cooled with cold air, and the anticorrosive materials 5 and 6 are solidified to prevent rustproof coated steel Take up the winding reel 43.

  In the above-described embodiment, the manufacture of the rust-proof coated steel stranded wire made of the steel stranded wire 3 in which one side wire 2 is twisted around the outer periphery of the core wire 1 as shown in FIG. 6 has been described. In this way, the middle layer wire 51 is twisted on the outer side of the core wire 50 and the outer layer wire 52 is twisted on the outer periphery thereof to form a multilayer steel twisted wire. As shown in FIG. 9, a rust-proof coated steel stranded wire 7 that is filled and coated with an outer-coated rust-proofing material 6 can be manufactured. As shown in FIG. The multi-layer steel twisting is performed by sequentially passing through the steel wire twisting machines 60 and 61 for twisting the outer layer wires 52, respectively, and twisting each layer and filling the internal voids in the same manner as described above. A rust-proof coated steel stranded wire made of wire can be molded. In the drawings showing the embodiments, the same or equivalent parts are denoted by the same reference numerals, and redundant description is omitted.

  In addition to this, although not shown in the drawing, for the multilayer steel stranded wire in which the core wire 50 and the middle layer wire 51 of the outer layer wire 52 are divided into a plurality of layers, the internal voids are similarly formed during the twisting process for each layer. A multi-layer rust-proof coated steel stranded wire can be manufactured by filling with an internally filled rust-proof material.

  In this case, the steel wire twisting machine 60 has the same structure as that of FIG. 2 described above, and the steel wire twisting machine 61 has an intermediate layer wire on the outer periphery of the twisted steel twisted wire 3 as shown in FIG. 51 and / or the outer layer wire 52 are twisted together, and the structure is the same as that of the twisting machine 60. The twisting machine 61 uses a steel stranded wire 3 in which the middle layer wire 50 is twisted around the outer periphery of the core wire 50, which is a single strand, as the center line, and more closely matches the outer layer wire 52 around the outer periphery. The heater 17 immediately before the alignment position preheats the steel stranded wire 3 composed of the core wire and the middle layer wire.

  Next, a case where the present invention is applied to a long steel material such as a single steel bar such as a modified steel bar and a single steel wire (not a stranded wire) will be described. In this case, as shown in FIG. 10, after passing through the long steel material heat stretching device 31, it passes through the descaling device 34, and then passes through the raw material floating tank 37 and passes through the cooler 42. Since each device is the same as described above, a duplicate description is omitted.

  If the long steel material is a steel bar that does not easily bend, use a steel bar that has been cut to a predetermined length. If the steel wire can be wound by a reel, it is wound on a reel (not shown) ) Are sequentially stretched and supplied, and after the coating is cooled, it is wound on a reel.

  In each of the above-described embodiments, the case where the heat stretching process, which is also a heat treatment, is performed after the blueing process, which is a heat treatment, is shown. Heating by a bluing furnace is used, and after the heating, when the temperature drops to a temperature required for resin deposition on the steel wire, coating with an external coating rust preventive material is performed. In addition to the above, the heat treatment includes various heat treatments for processing the steel wire and developing desired quality such as heat treatment for improving the uniform elongation.

  Further, the rust removal by the descaler 34 is performed when necessary and is not always necessary. In addition to the above, this descaling device may be sandblasting or shot peening.

  In the above-described embodiment, the long steel material is continuously passed through the powder coating raw material floating tank in which the powdered coating raw material is suspended by air in contact with the long steel material of the powder synthetic resin coating raw material. In addition to this, the so-called fluidized dipping method is used, but in addition to this, a long steel material is grounded, and a powdery coating material charged with static electricity is sprayed on the long steel material, so that it is attached by electrostatic attraction. An electroadsorption method may be used.

It is a processing-process figure of the 1st Example of this invention. It is sectional drawing which shows the twist processing machine part in the process of FIG. It is sectional drawing which shows an example of the same antirust coating apparatus of an outer peripheral surface. It is a processing-process figure of the 2nd Example of this invention. It is sectional drawing which shows an example of the twist processing apparatus of an intermediate | middle layer wire or an outer layer wire same as the above. It is a cut end view which shows the steel twisted wire of the state which filled the internal space | gap in the example shown in FIG. 1 with the antirust material. It is a cut end view showing an example of a rust-proof coated steel stranded wire after the same outer peripheral surface rust-proof coating step. It is a cut end view of the steel twisted wire of the state which twisted the middle layer wire and the outer layer wire in the second example of the present invention. It is a cut end view showing an example of a rust-proof coated steel stranded wire after the same outer peripheral surface rust-proof coating step. It is a processing-process figure which shows the 3rd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Core wire 2 Side wire 3 Steel twisted wire 5 Internal filling antirust material 6 Outer covering antirust material 7 Anticorrosion coated steel twisted wire 10 Steel wire twisting machine 11 Machine stand 12 Horizontal support shaft 13 Turntable 14 Reel 15 for twisted wire Core wire reel 17 Heater 20 Container 21 Inner peripheral surface 22 Anticorrosive material supply port 23 Resin heating melt extruder 24 Lid 25.26 Inlet 27 Twisted wire passage hole 28 Die 29 Electric heater 30 Brewing furnace 31 Heat stretch Heating furnace 33a, 33b Feeding mechanism 34 Descale device 35 Powder coating device 36 Powder synthetic resin coating raw material 37 Raw material floating tank 38 Bottom plate 39 Air introduction chamber 40 Blower 41a, 41b Long steel material insertion hole 42 Cooler 43 winding Reel 50 Core wire 51 Middle layer wire 52 Outer layer wire 60, 61 Steel wire twisting machine

Claims (6)

  After subjecting long steel materials such as steel wires and steel bars to heat treatment such as bluing treatment and / or heat stretching treatment, ethylene vinyl acetate copolymer (EVA) is applied to the long steel materials heated by the heat treatment. , Saponified ethylene vinyl acetate copolymer (EVOH), ethylene-methacrylic acid copolymer (EMAA), ionomer resin, powdered synthetic resin coating made of thermoplastic resin or fluorine resin having polar group such as ethylene ethyl acrylate When the raw material is brought into contact, the coating raw material is melted by the heat during the heat treatment of the long steel material, and is applied to the outer peripheral surface, and then is cooled and applied to the long steel material by being cooled. A rust-proofing method for a long steel material characterized by solidifying a raw material.   The rust-proofing method for a long steel material according to claim 1, wherein the long steel material is a PC steel material.   The rust-proofing method for a long steel material according to claim 1, wherein the long steel material is a modified steel bar.   The contact of the powdered synthetic resin coating raw material with the long steel material is performed by continuously passing the long steel material through a powder coating raw material floating tank in which the powdery coating raw material is floated by air. The antirust processing method with respect to the long steel materials of any one of -3.   The contact of the powdered synthetic resin coating raw material with the long steel material is performed by allowing the long steel material to be grounded, and by adhering the powdered coating raw material charged with static electricity to the steel material by electrostatic attraction. The rust prevention processing method with respect to the long steel material of any one of claim | item 1-3. Twist processing to make a steel stranded wire by laying one side or multiple layers on the outer periphery of the core wire or twisting the outer layer wire on the outer side of the middle layer wire to the outer periphery of the core wire, While performing heat treatment such as blueing treatment and / or heat stretching treatment, the space between each single strand constituting the steel stranded wire is filled with a rust-proofing material, and the outer periphery of the steel stranded wire is rust-proof In the rust prevention processing method for long steel materials covered with the material,
Supplying a rust preventive material composed of a thermoplastic synthetic resin heated and melted at the twisting position at the time of the twist processing to fill the gaps between the single strands of the steel stranded wire with the rust preventive material, and then The steel stranded wire is subjected to the heat treatment, and then the steel stranded wire heated by the heat treatment is subjected to ethylene vinyl acetate copolymer (EVA), ethylene vinyl acetate copolymer saponified product (EVOH), ethylene- By contacting a powdered synthetic resin coating raw material made of a thermoplastic resin having a polar group such as a methacrylic acid copolymer (EMAA), an ionomer resin, ethylene ethyl acrylate, or a fluorine resin, the coating raw material is made of a long steel material. For a long steel material characterized in that it is melted by heat and deposited on the outer peripheral surface, and then cooled, and then the coating raw material is solidified when melted and deposited on the long steel material. Rust processing method.

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