JP7263154B2 - Humidifier and processing system for cold drawing - Google Patents

Description

The present invention relates to cold drawing of metal materials having a lubricating coating.

Cold drawing, such as cold wire drawing and cold drawing, is a technique for reducing the cross-sectional area or changing the cross-sectional shape of a long metal material such as a tube, bar, or wire through a die. Cold drawing is usually performed after lubricating the metal material in advance for the purpose of preventing the occurrence of flaws (such as seizure) on the metal material, improving the life of the die, and improving the drawing speed.

As a lubricating treatment method, in order to improve treatment efficiency, a method is known in which a metallic material is coiled, a lubricating film treatment agent is brought into contact with the metallic material, and a lubricating film is formed by drying. However, when the metal material is coiled, the lubricating film treating agent does not reach the places where the metal materials are in contact with each other, so there are areas where the lubricating film is not adhered (also referred to as "film defects"). If cold drawing is performed in a state in which the lubricating film is not adhered to the part, there is a problem that the metal material is damaged starting from the non-adhered part.

In order to suppress the occurrence of such flaws, a lubricating film treatment agent is brought into contact with the dried coiled metal material, and while the coiled metal material is fed out, the cold drawing process is continuously performed immediately before passing through the die. In addition, it is common to apply a powder lubricant to the metal material having a lubricating film.

Japanese Patent Application Laid-Open No. 62-161418 (Patent Document 1) describes that when drawing a steel wire, it is coiled in advance and is subjected to pickling → water washing → film treatment (lime soap solution treatment or phosphoric acid treatment) by an immersion method. It describes that wire drawing is performed using a powder lubricant after performing a lubrication treatment in the process of salt treatment→lime soap solution treatment)→drying.

Japanese Patent Application Laid-Open No. 2000-345361 (Patent Document 2) discloses that metal materials such as iron, steel, stainless steel, chromium steel, molybdenum steel, titanium steel or other metal wires, bars, and pipes are pickled. or mechanical descaling followed by pretreatment of phosphate, borate, oxalate or lime soap coating followed by dry lubricant, water soluble lubricant or oil based lubricant as required It is described that drawing is performed using an agent or the like.

JP-A-62-161418 JP-A-2000-345361

When handling powdered lubricants, there is a problem that dust is generated and the work environment tends to deteriorate. Moreover, when the powder lubricant adheres excessively to the metal material having the lubricating film, there is also a problem that the appearance of the metal material having the lubricating film deteriorates due to excessive entrainment. Therefore, it is desirable to be able to prevent the occurrence of flaws in metal materials having a lubricating film during cold drawing without using a powder lubricant.

In view of the above circumstances, an object of the present invention is to provide an apparatus capable of preventing flaws from occurring in a metal material having a lubricating film during cold drawing without using a powder lubricant. and

As a result of intensive studies to solve the above problems, the present inventors found that by humidifying the air that is brought into contact with the metal material having a lubricating film before cold drawing, it is possible to achieve the above without using a powder lubricant. The inventors have also found that it is possible to prevent the occurrence of flaws in a metal material having a lubricating film during cold drawing, and have completed the present invention.

The invention is exemplarily specified as follows.
[1]
1. A humidifier for cold drawing, characterized by humidifying air to be brought into contact with a metal material having a lubricating film before cold drawing.
[2]
The humidifying apparatus for cold drawing according to [1], wherein the air to be brought into contact with the metal material having the lubricating film is humidified to a humidity of 70 to 100% RH and 5 to 40°C.
[3]
[1] A processing system comprising the humidifying device for cold drawing according to [1] and a processing device for cold drawing a metal material having a lubricating film.

By using the humidifying device for cold drawing according to one embodiment of the present invention, defects such as seizure occur in the metal material having a lubricating film during cold drawing without using a powder lubricant. You will be able to prevent

It is a mimetic diagram showing an example of composition of a processing system concerning the present invention. FIG. 2 is a schematic diagram showing the arrangement of a humidifying device for cold drawing and dies used in Examples.

Embodiments of the present invention, including cold drawing humidifiers and processing systems, are described in detail below. In addition, the present invention can be arbitrarily changed within the scope including the gist thereof, and is not limited to the following embodiments.

(1. Metal material)
The material of the metal material according to the present invention is not particularly limited. metal materials.

The shape of the metal material according to the present invention is not particularly limited as long as it is a shape suitable for cold drawing, and examples thereof include elongated shapes such as tubes, bars and wires.

A metal material according to the present invention has a lubricating film. Typically, the metal material has a portion where the lubricating film is not adhered, but the portion where the lubricating film is not adhered may not exist. Any known lubricating coating can be used as the lubricating coating, and there is no particular limitation, but lubricating coatings typically containing inorganic salts and lubricants can be mentioned. The lubricating coating may be a single layer or may have a multi-layer structure of two or more layers.

Inorganic salts include water-soluble inorganic salts such as borates, phosphates, silicates, and tungstates. These may be used alone or in combination of two or more. Salts of these water-soluble inorganic salts include, for example, alkali metal salts (sodium salt, potassium salt, lithium salt, etc.), ammonium salts and the like. Phosphates also include salts of condensed phosphoric acid such as tripolyphosphoric acid, metaphosphoric acid and pyrophosphoric acid. In this specification, the term “water-soluble” means that the solubility in water at room temperature (25° C.) {mass (g) of solute dissolved in 100 g of water} is at least 1 g, preferably 10 g or more. means.

Examples of lubricants include waxes, polytetrafluoroethylene, fatty acid soaps, fatty acid metal soaps, fatty acid amides, alkaline earth metal salts of organic acids, molybdenum disulfide, tungsten disulfide, graphite, melamine cyanurate, and layered structure amino acid compounds. and layered clay minerals. Among these, waxes, polytetrafluoroethylene, fatty acid soaps, fatty acid metal soaps, fatty acid amides, alkaline earth metal salts of organic acids, melamine cyanurate, layered structure amino acid compounds and layered clay minerals are more preferable. These may be used alone or in combination of two or more.

Specific examples of the wax include polyethylene wax, paraffin wax, microcrystalline wax, polypropylene wax, and carnauba wax. Although the melting point of the wax is not particularly limited, it is preferably 60 to 120°C, more preferably 60 to 80°C. Specific examples of fatty acid soaps include sodium myristate, potassium myristate, sodium palmitate, potassium palmitate, sodium stearate and potassium stearate. Specific examples of fatty acid metal soaps include calcium stearate, zinc stearate, barium stearate, magnesium stearate, and lithium stearate. Further, the fatty acid amide is an amide compound having two fatty acids, and specific examples include ethylenebislauric acid amide, ethylenebisstearic acid amide, ethylenebisbehenic acid amide, NN'-distearyladipic acid amide, ethylenebis Oleic acid amide, ethylene bis erucic acid amide, hexamethylene bis oleic acid amide, NN'-dioleyl adipic acid amide. Specific examples of alkaline earth metal salts of organic acids include calcium oxalate, barium oxalate, calcium malate, barium malate, calcium succinate, barium succinate, calcium glutarate, barium glutarate, citric acid, calcium acid, barium citrate, calcium tartrate, and barium tartrate. A layered structure amino acid compound is an amino acid or derivative thereof having a hydrocarbon group with 11 or more carbon atoms in its molecular structure. A specific example is N-lauroyl-L-lysine [C ₁₁ H ₂₃ CONH(CH ₂ ) ₄ CH(NH ₂ )COOH]. Layered clay minerals include natural products and synthetic products of the smectite group, vermiculite group, mica group, brittle mica group, pyrophyllite group, and kaolinite group. More detailed examples include montmorillonite, beidellite, nontronite, saponite, iron saponite, hectorite, sauconite, stevensite, and di. vermiculite, tri. vermiculite, muscovite, paragonite, illite, phlogopite, biotite, lepidolite, and lepidolite in the mica group; margarite and clintonite in the brittle mica group; pyrophyllite, talc in the pyrophyllite group; Dickite, nacrite, halloysite, chrysotile, lizardite, and antigorite. Further, these layered clay minerals may be subjected to an organic treatment to introduce an organic modifier between the layers. The organic modifier is an alkylamine or alkyl quaternary ammonium salt, and specific examples include stearyldimethylamine, distearylamine, distearyldimethylamine, stearyltrimethylammonium chloride, and distearyldimethylammonium chloride.

The lubricating coating can be formed by wet coating treatment using a lubricating coating treatment agent containing an inorganic salt and a lubricant. Moreover, in order to improve the treatment efficiency, the wet coating treatment may be performed while the metal material is coiled or bundled. The method for forming a lubricating film on the surface or surface of a metal material by wet coating treatment is not particularly limited, but includes dipping, flow coating, spraying, or a combination thereof. After performing the wet coating treatment, it is desirable to perform a drying process.

The lubricating film treatment agent can be produced by appropriately mixing an inorganic salt, a lubricant, and other ingredients with water, which is a liquid medium. Mixing is performed by general methods such as propeller stirring and homogenizer. Other components that can be added to the lubricating film treating agent include, for example, resin components, water-soluble rust inhibitors, viscosity modifiers, inhibitors, and pH modifiers.

The resin component can be added for the purpose of acting as a binder, improving the adhesion between the metal material and the film, imparting leveling properties by thickening action, stabilizing the dispersed components, and improving barrier properties. The resin component used here is not particularly limited as long as it has a film-forming property, and is generally supplied in a state dissolved or dispersed in water. Specific examples of resin components include vinyl resins, acrylic resins, epoxy resins, urethane resins, phenol resins, cellulose derivatives, polymaleic acid, polyolefins, and polyesters. These may be used alone or in combination of two or more.

A viscosity modifier can be added for the purpose of imparting leveling properties and thixotropy. Specific examples of viscosity modifiers include smectite clay minerals such as montmorillonite, sauconite, beidellite, hectorite, nontronite, saponite, iron saponite, and stevensite, and inorganic thickeners such as finely divided silica, bentonite, and kaolin. is mentioned. These may be used alone or in combination of two or more.

Water-soluble rust inhibitors and inhibitors can be added for the purpose of improving corrosion resistance. Specific examples of water-soluble rust inhibitors and inhibitors include various organic acids such as oleic acid, dimer acid, tartaric acid, and citric acid; various chelating agents such as EDTA, NTA, HEDTA, and DTPA; alkanolamines such as triethanolamine; Amine salts of -t-butylbenzoic acid, carboxylic acid amine salts, dibasic acid amine bases, combined use of alkenylsuccinic acid and its water-soluble salts with aminotetrazole and its water-soluble salts, and the like. These may be used alone or in combination of two or more.

A pH adjuster can be added to enhance the stability of the liquid. Specific examples include lithium hydroxide, sodium hydroxide, and potassium hydroxide. These may be used alone or in combination of two or more.

It is preferable to perform cleaning treatment for the purpose of removing oxide scale grown by annealing and various contaminants (such as oil) before wet coating treatment is applied to the metal material. Specifically, it is preferable to perform at least one cleaning treatment selected from the group consisting of shot blasting, sand blasting, wet blasting, peeling, degreasing and pickling. Only one kind of cleaning treatment may be performed, or two or more kinds of cleaning treatments may be combined and sequentially performed. After each cleaning treatment, a water washing treatment step may be performed. Moreover, after the cleaning treatment, a drying step may be performed before performing the wet coating treatment.

The degreasing step can be performed, for example, by bringing a known acid degreasing agent or alkaline degreasing agent into contact with the surface or surface of the metal material by a conventional method. Pickling can be performed, for example, by bringing a known nitric acid detergent or sulfuric acid detergent into contact with the surface or surface of the metal material by a conventional method.

Another layer may exist between the metal material and the lubricating coating. Another layer is, for example, a metal oxide layer. Further, a known base film may be present between the metal material and the lubricating film for the purpose of improving workability and corrosion resistance.

(2. Humidifier for cold drawing)
In one embodiment, a humidifying apparatus for cold drawing according to the present invention is configured to humidify air that is brought into contact with a metal material having a lubricating coating prior to cold drawing. The humidifier for cold drawing is not particularly limited as long as it is configured to humidify the air to be brought into contact with the metal material having the lubricating film before cold drawing.

The air to be brought into contact with the metal material having the lubricating film is preferably humidified to a humidity of 70% RH or higher, more preferably 80% RH or higher. Moreover, it is preferable that water droplets do not adhere to the surface of the metal material having the lubricating film (condensation-free conditions). Therefore, the air to be brought into contact with the metal material having the lubricating film is preferably humidified to a humidity of 100% RH or less, more preferably 95% RH or less.

The temperature of the air to be brought into contact with the metal material having the lubricating film is not particularly limited, but normal temperature (5 to 40° C.) that does not particularly require heating or cooling is preferable from the viewpoint of cost. Moreover, from the viewpoint of preventing dew condensation, it is more preferable that the temperature is 25 to 40° C., at which the amount of saturated water vapor increases.

Therefore, in a preferred embodiment, the air to be brought into contact with the metal material having the lubricating film is humidified by a humidifier for cold drawing to a humidity of 70 to 100% RH (relative humidity) and 5 to 40°C. be.

The contact time between the air humidified by the cold drawing humidifier and the metal material having the lubricating film is preferably 0.2 seconds or longer, more preferably 0.4 seconds or longer. Although the upper limit of this contact time is not particularly set, from the viewpoint of production efficiency, it is preferably 4 seconds or less, more preferably 2 seconds or less, and even more preferably 1 second or less.

FIG. 1 shows a configuration example of a humidifying device 150 for cold drawing. The cold drawing humidifier 150 includes a humidifier 151 , a pipe 152 and a humidifier box 153 . The humidifier 151 is not particularly limited, but is preferably a humidifier with a humidity control device. The air humidified by the humidifier 151 can flow into the humidification box 153 through the pipe 152 . In addition, the humidification box 153 has an inlet 154 and an outlet 155 for the metal material 120 with the lubricating film, and is configured so that the metal material 120 with the lubricating film can pass through the interior of the humidification box 153. ing. Therefore, while the metal material 120 having the lubricating film passes through the humidification box 153, the metal material 120 having the lubricating film comes into contact with the humidified air.

(3. Machining system)
FIG. 1 shows a configuration example of a processing system 100 according to the present invention. The processing system 100 includes a cold drawing humidifying device 150 and a processing device 140 for cold drawing a metal material having a lubricating film in contact with the air humidified by the cold drawing humidifying device 150 . The description of the humidifier 150 for cold drawing is as described above. A processing device 140 for cold drawing a lubricating film-coated metal material has a lubricating film-coated metal material supply device 141 , a die 142 , and a lubricating film-coated metal material winding device 143 . The supply device 141 can unwind the metal material 110 having a lubricating coating wound in a coil shape and send it toward the die 142 . On the other hand, the winding device 143 can wind the metal material 120 having the lubricating film that has passed through the die 142 into a coil at a desired speed. The processing device 140 may include pinch rolls and straightening rolls for linearly straightening the metal material 120 having a lubricating film fed from the supply device 141 and then sending it to the die 142 . In one embodiment, processing system 100 does not have a cooling device for cooling the metal material with the lubricating coating. In another embodiment, processing system 100 does not have a heating device for heating a metallic material having a lubricating coating. In yet another embodiment, the processing system 100 does not have a cooling device for cooling the metallic material having the lubricating coating and a heating device for heating the metallic material having the lubricating coating.

In the processing system 100 shown in FIG. 1, the die 142 is installed outside the humidification box 153 . It is preferable to prevent the metal material 120 having the lubricating film from drying after the metal material 120 having the lubricating film in contact with the humidified air leaves the humidification box 153 and before passing through the die 142 . Therefore, after the metal material 120 with the lubricating film in contact with the humidified air leaves the humidification box 153, it is preferable that the metal material 120 with the lubricating film starts passing through the die 142 within 1 second, and 0.4 More preferably, it begins passing through the die 142 within seconds.

The die 142 may be installed inside the humidification box 153 . By installing the die 142 inside the humidification box 153, the metal material 120 having the lubricating film in contact with the humidified air leaves the humidifying box 153 and passes through the die 142. It has a lubricating film. It is possible to prevent the metal material from drying out.

An embodiment of a wire drawing system to which the present invention is applied is shown below. However, the present invention is not limited by this embodiment.

(test material)
As a test material, a linear straightening material of chromium molybdenum steel (SCM435) specified by JIS G 4053:2016 with a wire diameter of 13.0 mm and a length of 1.2 m was used. In addition, the tip of the straightening material was processed into a wire diameter of 11.0 mm and a length of 20 cm using a roller die so as to be introduced into the die.

(Accelerated seizure test)
For the purpose of promoting seizure, a 2.5 mm wide × 50 mm long heat-resistant tape (manufactured by 3M Japan, polyimide electrical insulating tape) is attached to the rear end of the above test material, and a lubricating film is formed with the tape attached. The treatment for this was carried out in the steps shown below. Since the lubricating film does not adhere to the taped area, seizure is likely to occur. This test is a test method assuming a film defect in the interline portion (where metal materials are in contact with each other) when a metal material having a lubricating film is coiled and treated.

(Method for forming lubricating film)
The treatment for forming the lubricating film was performed in the following steps.
(1) Degreasing: Commercially available degreasing agent (Fine Cleaner E6400, manufactured by Nihon Parkerizing Co., Ltd., concentration 20 g/L, temperature 60°C, immersion for 15 minutes)
(2) Water washing: tap water, temperature about 20°C, shower for 30 seconds (3) Pickling: 17.5% hydrochloric acid, temperature about 20°C, immersion for 20 minutes (4) Water washing: tap water, temperature about 20°C, shower 1 minute (5) Neutralization: Commercially available neutralizing agent (Preparen 27, manufactured by Nihon Parkerizing Co., Ltd., concentration 1 g/L, temperature about 20°C, immersion for 1 minute)
(6) Lubricating film treatment: commercially available water-based lubricating film treating agent (lubricating film treating agent shown in Table 1, temperature 60 ° C., immersion for 1 minute, film amount: 7 g / m ² )
(7) Drying: jet heater, 100°C, 20 minutes

(Wire drawing test)
After removing the tape from the test material with a wire diameter of 13.0 mm and a length of 1.2 m on which the lubricating film was formed by the above method, a wire drawing test was performed on the test material at about 20 ° C. under the conditions shown in Table 1. carried out. In addition, the wire drawing test was carried out five times for each condition. In Examples 1 to 9, a humidifier was used to humidify the air to the humidity shown in Table 1, and the wire was drawn immediately after passing the test material through the humidification box into which the humidified air flowed. In addition, the atmospheric temperature in the humidification box was set to about 20°C. FIG. 2 shows the configuration of the used humidifier for cold drawing. As the humidifier 151, a hybrid humidifier KJ-373HE-WH manufactured by CCP was used. The humidifying box 153 had a rectangular parallelepiped shape of 76 mm×76 mm×180 mm, and was installed so that the plane of 76 mm×76 mm was parallel to the wire drawing direction. The distance from the exit of humidification box 153 to the entrance of die 142 was 40 mm. On the other hand, in Comparative Examples 1 to 5, wire drawing was carried out without the humidifying process before wire drawing. The drawing speed was about 10 m/min in both the examples and the comparative examples.

(Evaluation method)
The presence or absence of appearance defects such as seizure in the lubricating film uncoated portion of the test material subjected to the wire drawing test was visually evaluated according to the following evaluation criteria. Table 1 shows the evaluation results.

(Evaluation criteria for the presence or absence of appearance defects such as seizure)
◎: 0 occurrences of seizure, etc. ○: 1 to 4 occurrences of seizure, etc. ×: 5 occurrences of seizure, etc.

(使用ダイス)
減面率7.5%で使用したダイス…ダイス内径：12.50mm, チップ径：35mm, チップ高さ：25mm, ベアリング長：3.9mm, ケース径：85mm, ケース高さ：40mm, ダイス両角：17°
減面率16.9%で使用したダイス…ダイス内径：11.85mm, チップ径：35mm, チップ高さ：25mm, ベアリング長：3.9mm, ケース径：85mm, ケース高さ：40mm, ダイス両角：17°
（潤滑皮膜処理剤）
ＦＬ－Ｅ２０００：日本パーカライジング（株）製
ＦＬ－Ｅ２２００：日本パーカライジング（株）製
ＦＬ－Ｅ７４０Ｃ：日本パーカライジング（株）製
ＦＬ－Ｅ７７１Ａ：日本パーカライジング（株）製

(Dice used)
Die used with a reduction rate of 7.5%... Die inner diameter: 12.50mm, Tip diameter: 35mm, Tip height: 25mm, Bearing length: 3.9mm, Case diameter: 85mm, Case height: 40mm, Die angle: 17°
Die used with a reduction rate of 16.9%...Die inner diameter: 11.85mm, tip diameter: 35mm, tip height: 25mm, bearing length: 3.9mm, case diameter: 85mm, case height: 40mm, both sides of the die: 17°
(Lubricating film treatment agent)
FL-E2000: manufactured by Nihon Parkerizing Co., Ltd. FL-E2200: manufactured by Nihon Parkerizing Co., Ltd. FL-E740C: manufactured by Nihon Parkerizing Co., Ltd. FL-E771A: manufactured by Nihon Parkerizing Co., Ltd.

100 processing system 110 coiled metal material with lubricating film 120 metal material with lubricating film 140 processing device for cold drawing metal material with lubricating film 141 supplying device 142 for metal material with lubricating film dies 143 Winding device for metal material having lubricating film 150 Humidifying device for cold drawing 151 Humidifier 152 Piping 153 Humidifying box 154 Inlet 155 Outlet

Claims (2)

A humidifier for cold drawing that humidifies the air that is brought into contact with the metal material having the lubricating film before cold drawing and brings the metal material that has the lubricating film into contact with the humidified air, and at the end of the contact. a processing device that initiates cold drawing of a metallic material having a lubricating coating within 1 second from . The processing according to claim 1 , wherein the humidifying device for cold drawing humidifies the air to be brought into contact with the metal material having a lubricating film so that the humidity is 70 to 100% RH and the temperature is 5 to 40 ° C. system .

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