JP2016203192A - Method and apparatus of descaling of metal wire material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus capable of removing effectively oxidized scale on the surface of a metal wire material.SOLUTION: Descaling includes injecting mixture (9) of water and hard particles from plural nozzles (8) to the surface of a metal wire material (W). The plural nozzles (8) includes plural self-cleaning type nozzles which implement injection at an injection angle (θ) not more than 90° against the metal wire material (W). The injection angle (θ) is the angle which is formed by the central axis (X) of the injection and the vector (Vt) showing the transportation direction with a crossing point (P) between the central axis (X) and the surface of the metal wire material as the starting point.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a metal wire descaling method and apparatus.

  2. Description of the Related Art A hot rolling apparatus that manufactures a metal wire such as a strip wire from a slab such as a billet is known. This hot rolling apparatus includes, for example, a heating furnace, a rough rolling mill, a finish rolling mill, a pinch roll, and a winder, which are arranged in order from the upstream side. In this apparatus, the slab is heated in the heating furnace and continuously rolled, then becomes a wire, and is wound in a coil shape by the winder. An oxide scale such as an oxide film adheres to the surface of the metal wire wound up in this way. The manufactured metal wire may be subjected to drawing using a wire drawing die for the purpose of improving dimensional accuracy and mechanical properties. In this case, it is necessary to perform descaling to remove the oxide scale before the drawing process.

  In general, pickling is widely used for descaling metal wires. Pickling is a method of descaling a metal wire wound in a coil shape by immersing it in an acid bath, which can efficiently remove various oxide scales by optimizing the type, concentration and temperature of the acid. (For example, see Patent Document 1).

  In addition to pickling, there is a blasting descaling that unwinds a coiled metal wire, stretches it in a straight line, and causes hard particles to collide with the surface of the running metal wire at high speed for descaling. is there. A representative example is shot blasting in which spherical particles are projected onto the surface of a metal wire by centrifugal force of an impeller (see, for example, Patent Document 2).

  On the other hand, Patent Document 3 discloses a wet honing apparatus that sprays a mixture (slurry) in which water and hard particles are uniformly mixed onto a workpiece by compressed air as an apparatus for polishing.

JP 2010-222602 A JP 2000-33417 A Japanese Patent Laid-Open No. 2-167664

  The descaling by pickling disclosed in Patent Document 1 is not preferable because it involves costs such as disposal of spent acid and contamination of the work environment by evaporation of the acid. In addition, the shot blast disclosed in Patent Document 2 has problems such that the oxide scale that is thinly adhered to the ground iron cannot be completely removed, and that broken particles pollute the work environment.

  An object of this invention is to provide the descaling method and apparatus which can remove an oxide scale effectively, suppressing the contamination of a working environment.

  In order to achieve the above object, the present inventors have achieved a technique similar to the technique described in Patent Document 3, that is, a technique for injecting a mixture containing water and hard particles onto the surface of a workpiece (hereinafter referred to as “wet”). It has been conceived to be applied to descaling of metal wires. This technique makes it possible to effectively remove the oxide scale on the surface of the metal wire while suppressing contamination of the work environment due to generation of dust and the like. However, this technique involves the following new problems.

  First, when the metal wire is descaled by wet blasting, scattered slurry and removed scale debris adhere to the surface of the metal wire. To remove adhering slurry and scale debris, it is effective to wash with liquid following the blasting process. However, after washing, the slurry and scale exfoliation remain, and processing such as wire drawing is performed in the subsequent process. Then, there is a risk of processing defects such as tool seizure and tool wear.

  Moreover, in order to perform sufficient washing | cleaning, since the washing | cleaning process of multiple times is required, there exists a subject that cost increases and the calculated | required space is large.

  Furthermore, even if sufficient cleaning is performed in the cleaning process, the metal wire is transported with at least the slurry and scale debris adhered between the wet blasting process and the cleaning process. When the wire comes into contact, slurry or scale debris may be pushed in.

  What is provided is a method for descaling the surface of a metal wire while suppressing the inconvenience, wherein the metal wire is transported in a transport direction along an axis thereof, and each is a mixture of water and hard particles. A plurality of nozzles capable of injecting water at a plurality of positions different from each other in the circumferential direction of the metal wire around the metal wire, and a mixture containing water and hard particles respectively from the plurality of nozzles Spraying the surface of the metal wire onto the surface of the metal wire. The plurality of nozzles include a plurality of self-cleaning nozzles. Each self-cleaning type nozzle ejects the mixture in a direction in which the injection angle θ is 90 ° or less, thereby removing foreign matters generated by the injection of the mixture and generated on the surface of the metal wire by the injection of the mixture. To do. The jetting angle θ is an angle formed by a central axis of jetting the mixture from the self-cleaning nozzle and a vector indicating the transport direction starting from an intersection of the central axis and the surface of the metal wire. .

  Also provided is an apparatus for descaling the surface of a metal wire, a transport device for transporting the metal wire in a transport direction along its axis, each spraying a mixture of water and hard particles. A plurality of nozzles, each of which is disposed at a plurality of different positions in the circumferential direction of the metal wire around the metal wire, and a mixture containing water and hard particles from each of the plurality of nozzles. And scaling the surface of the metal wire by spraying on the surface. The plurality of nozzles include a plurality of self-cleaning nozzles. Each self-cleaning type nozzle ejects the mixture in a direction in which the injection angle θ is 90 ° or less, thereby removing foreign matters generated by the injection of the mixture and generated on the surface of the metal wire by the injection of the mixture. To do. The jetting angle θ is an angle formed by a central axis of jetting the mixture from the self-cleaning nozzle and a vector indicating the transport direction starting from an intersection of the central axis and the surface of the metal wire. .

  In the method and apparatus, the oxide scale on the surface of the metal wire can be effectively removed by spraying the mixture onto the surface of the metal wire from the plurality of nozzles. Furthermore, the self-cleaning type nozzles included in the plurality of nozzles can remove deposits generated on the surface of the metal wire by the injection of the mixture by the injection of the mixture of the self-cleaning type nozzle itself. Inconveniences such as seizure due to the deposits in subsequent processing (for example, wire drawing) can be effectively suppressed.

  In the method and apparatus, it is preferable that all of the plurality of nozzles are the self-cleaning nozzles. This is because the deposits on the surface of the metal wire generated due to the injection of the mixture from the plurality of nozzles can be respectively removed by the injection of the mixture of the nozzle itself, and the inconvenience caused by the deposits. Can be suppressed more effectively.

  In this case, it is preferable that the plurality of self-cleaning nozzles are arranged at equal intervals in the circumferential direction. This arrangement allows uniform descaling in the circumferential direction.

  On the other hand, in the method and apparatus, the plurality of nozzles may include non-self-cleaning nozzles that inject the mixture in a direction in which the injection angle θ exceeds 90 °, in addition to the plurality of self-cleaning nozzles. Good. In this case, at least one self-cleaning nozzle of the plurality of self-cleaning nozzles is disposed downstream of the non-self-cleaning nozzle in the transport direction, and the non-self-cleaning nozzle with respect to the surface of the metal wire At least a portion of the injection region in the circumferential direction overlaps with the injection region in the circumferential direction with respect to the surface of the metal wire of the at least one self-cleaning nozzle disposed on the downstream side of the non-self-cleaning nozzle. It is good to be. This arrangement makes it possible to remove deposits on the surface of the metal wire produced by jetting the mixture from the non-self-cleaning nozzle by jetting the mixture from the self-cleaning nozzle located downstream thereof. .

  Specifically, for example, the plurality of nozzles are respectively arranged at five or more positions arranged at equal intervals in the circumferential direction, and the downstream side of the non-self-cleaning type nozzle in the transport direction and the non-self-cleaning type It is preferable that the nozzle and the nozzle adjacent to both sides in the circumferential direction are the self-cleaning nozzles. According to this arrangement, the deposits on the surface of the metal wire resulting from the jetting of the mixture from the non-self-cleaning nozzle are arranged on the downstream side and in the circumferential direction with respect to the non-self-cleaning nozzle. The deposits can be more reliably removed by the nozzles adjacent to both sides.

It is the figure which showed the relationship between a metal wire and a non-self-cleaning nozzle. It is the figure which showed the relationship between a metal wire and the self-cleaning type nozzle whose injection angle (theta) is 90 degrees. It is the figure which showed the relationship between a metal wire and the self-cleaning type nozzle whose injection angle (theta) is less than 90 degrees. It is the side view which showed the example by which the some nozzle was arrange | positioned helically with respect to the metal wire along a conveyance direction. It is the figure which showed the example by which the some nozzle was arrange | positioned with respect to the metal wire along a conveyance direction in zigzag form. It is the figure which showed the example by which the several nozzle was arrange | positioned with respect to the metal wire along a conveyance direction in the said conveyance direction. It is the cross-sectional front view which showed the example of arrangement | positioning of the some nozzle with respect to the metal wire about the circumferential direction. It is the figure which showed the relationship between the injection angle (theta) of the nozzle with respect to a metal wire, and the hard particle residual amount on the surface of the said metal wire. It is a cross-sectional front view which shows the example of arrangement | positioning of the some nozzle with respect to the metal wire about the circumferential direction. It is a cross-sectional front view which shows the example of arrangement | positioning of the some nozzle with respect to the metal wire about the circumferential direction. It is a cross-sectional front view which shows the example of arrangement | positioning of the some nozzle with respect to the metal wire about the circumferential direction. It is a cross-sectional front view which shows the example of arrangement | positioning of the some nozzle with respect to the metal wire about the circumferential direction. It is a cross-sectional front view which shows the example of arrangement | positioning of the some nozzle with respect to the metal wire about the circumferential direction. It is a cross-sectional front view which shows the example of arrangement | positioning of the some nozzle with respect to the metal wire about the circumferential direction. It is a cross-sectional front view which shows the example of arrangement | positioning of the some nozzle with respect to the metal wire about the circumferential direction. It is a cross-sectional front view which shows the example of arrangement | positioning of the some nozzle with respect to the metal wire about the circumferential direction. It is a cross-sectional front view which shows the example of arrangement | positioning of the some nozzle with respect to the metal wire about the circumferential direction. It is a cross-sectional front view which shows the example of arrangement | positioning of the some nozzle with respect to the metal wire about the circumferential direction. It is the figure which showed the outline of the equipment for performing the surface treatment including descaling with respect to a metal wire.

  Hereinafter, a descaling method and apparatus for a metal wire W according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 19 schematically shows a surface treatment facility 2 to which the descaling method and apparatus are applied.

  The metal wire W supplied to the surface treatment facility 2 is produced from a raw material such as a billet by using a hot rolling apparatus (not shown). The hot rolling apparatus includes, for example, a heating furnace, a rough rolling mill, a finish rolling mill, a pinch roll, and a winder, which are arranged in order from the upstream side in the transport direction of the metal wire W. The slab is heated in the heating furnace and continuously rolled in the rolling mills, then becomes a metal wire W, and is wound in a coil shape by the winder. The metal wire W wound in a coil shape in this way is supplied to the surface treatment facility 2. In the surface treatment facility 2, an appropriate treatment is performed on the metal wire W, and this treatment includes descaling for removing oxide scale on the surface.

  As shown in FIG. 19, the surface treatment facility 2 includes a supply stand 3 on which a coil material before wire drawing is disposed, and a descaling unit 1 that performs descaling on a metal wire W unwound from the supply stand 3. And a winding device 5 that winds up the metal wire W from which the oxide scale has been removed by the descaling unit 1. The winding device 5 constitutes a conveying device that conveys the metal wire W in the conveying direction along its axis, and the conveying device and the descaling unit 1 constitute a descaling device. Between the descaling apparatus 1 and the supply stand 3, for example, as shown in FIG. 19, a straightening straightener 6 that straightens the metal wire W may be provided. Further, between the descaling device 1 and the winding device 5, for example, as shown in FIG. 10, a coating device 7 for coating the surface of the metal wire W, or the metal wire W is drawn to a desired wire diameter. A wire drawing die 4 or the like may be provided.

  The descaling unit 1 includes a plurality of nozzles 8. The plurality of nozzles 8 are arranged around the metal wire W transported in the transport direction. Specifically, the plurality of nozzles 8 are respectively disposed at a plurality of different positions in the circumferential direction of the metal wire W. Each nozzle 8 sprays slurry 9, which is a mixture of water and hard particles, onto the surface of the metal wire W, thereby performing descaling to remove oxide scale on the surface of the metal wire W.

  In this embodiment, the nozzles 8 are arranged so as to be aligned along the conveying direction along the axis of the metal wire W, and are equally spaced in the circumferential direction around the axis of the metal wire W, that is, at an equal angle. Is placed.

  There are various examples of the arrangement. In the example shown in FIG. 4, the nozzles 8 are spirally arranged along the transport direction. As used herein, the term “spiral arrangement” means that when the number of the plurality of nozzles 8 is 4 or more, for example, as shown in FIGS. 11 to 15, from the transport direction along the axis of the metal wire W. The arrangement is such that the positions of the nozzles 8 arranged in order from the upstream side proceed along the circumferential direction.

  The numbers in the circles shown in FIGS. 9 to 18 indicate the order of the nozzles 8 counted from the upstream side in the transport direction.

  In the example shown in FIG. 5, the plurality of nozzles 8 are arranged in a staggered manner along the transport direction. As used herein, the “staggered arrangement” means that, when the number of the plurality of nozzles 8 is four or more, for example, as shown in FIGS. 11 to 15, from the transport direction along the axis of the metal wire W. The arrangement is such that the positions of the nozzles 8 arranged in order from the upstream side as viewed are alternately distributed to the left and right.

  In FIG. 6, the plurality of nozzles 8 are arranged at equal angles in the circumferential direction of the metal wire W at the same position in the transport direction of the metal wire W.

  As a feature of the descaling unit 1, the plurality of nozzles 8 include a plurality of self-cleaning nozzles. Each self-cleaning nozzle, like the nozzle 8 shown in FIGS. 2 and 3, oxidizes the surface of the metal wire W by injecting the mixture in an orientation in which the injection angle θ is 90 ° or less than 90 °. In addition to removing the scale, it has a function of removing foreign matters generated on the surface of the metal wire W by jetting the mixture by jetting the mixture. Here, the injection angle θ is a vector indicating the transport direction starting from the central axis X of the injection of the mixture from the self-cleaning nozzle and the intersection P between the central axis X and the surface of the metal wire W. The angle formed by Vt.

  All of the plurality of nozzles 8 are preferably self-cleaning nozzles. Furthermore, if these self-cleaning nozzles are arranged at equal intervals in the circumferential direction of the metal wire W, more uniform descaling can be performed.

  On the other hand, the plurality of nozzles 8 are not self-cleaning nozzles represented by the nozzles 8 shown in FIGS. 2 and 3, but are non-self-cleaning nozzles, that is, the nozzles 8 shown in FIG. , A nozzle for injecting the mixture at an injection angle θ exceeding 90 ° with respect to the metal wire W may be included. In this case, at least one of the plurality of self-cleaning nozzles is disposed downstream of the non-self-cleaning nozzle, and the circumferential direction of the non-self-cleaning nozzle with respect to the surface of the metal wire W At least a part, preferably all, of the injection region with respect to the circumferential direction of the at least one self-cleaning nozzle disposed on the downstream side of the non-self-cleaning nozzle with respect to the surface of the metal wire. It is preferable that they overlap. This is because the foreign matter adhering to the surface of the metal wire W due to the injection of the mixture from the non-self-cleaning nozzle is caused by the mixture from the self-cleaning nozzle located downstream of the non-self-cleaning nozzle. It is possible to remove by jetting.

  Also in this case, it is preferable that the plurality of nozzles are arranged at equal intervals in the circumferential direction. Further, in such an arrangement, the plurality of nozzles 8 are respectively arranged at five or more positions arranged in the circumferential direction, and the downstream side of the non-self-cleaning nozzle and the non-self-cleaning nozzle in the transport direction. It is preferable that all the nozzles adjacent in the circumferential direction are the self-cleaning nozzles.

  The reason why the arrangement shown above is preferable is as follows, and this point is a matter that the present inventors have found through intensive studies.

  In the descaling apparatus 1, the mixture, that is, the slurry 9 sprayed from the respective nozzles 8 collides with the surface of the metal wire W transported in the transport direction, and at least a part of the mixture repels and scatters. At this time, the present inventors have the behavior of the rebound and scattering of the slurry 9 by the injection angle θ, that is, the angle θ formed by the central axis X of the injection from the nozzle 8 and the vector Vt indicating the transport direction. In contrast, it has been found that the adhesion / remaining state of the hard particles or scale strips on the metal wire W is different.

  For example, as shown in FIG. 1, when the nozzle 8 injects the slurry 9 at an injection angle θ exceeding 90 °, the slurry 9 scatters as it is in the transport direction of the metal wire W after colliding with the surface of the metal wire W. Therefore, the metal wire W is sent to a subsequent process while the hard particles contained in the slurry 9 and the peeled scale pieces remain attached to the surface of the metal wire W as the deposit 10.

  On the other hand, as shown in FIG. 2, when the nozzle 8 injects the slurry 9 at an injection angle θ equal to 90 °, the metal wire W does not rebound in the transport direction and in the direction opposite to the transport direction, Almost no scattering of hard particles or flakes of the slurry 9 occurs. Even if the scattering occurs, the hard particles and the flakes of the slurry 9 are relatively likely to be washed away by the subsequent slurry 9 that is further sprayed to the position. Therefore, the remaining amount of the deposit 10 when θ = 90 ° is smaller than when θ> 90 °. Furthermore, as shown in FIG. 3, when the nozzle 8 injects the slurry 9 at an injection angle θ of less than 90 °, that is, when injecting the metal wire W in the direction opposite to the conveying direction, the hard particles and scale debris are conveyed. Since the hard particles and the scale strips adhere to the surface of the metal wire W as the deposit 10 because the particles are scattered in the opposite direction, the slurry 9 is sprayed as the metal wire W is transported thereafter. Since it is moved to the position, it is easily washed away by the injection of the slurry 9. In this way, the remaining deposit 10 is sufficiently suppressed.

  FIG. 8 shows the result of measuring the relationship between the injection angle θ of one nozzle 8 and the remaining amount WR of the hard particles and scale debris on the surface of the metal wire W. As shown in FIG. 8, the remaining amount WR of the deposit 10 is large in the region of θ ≧ 95 °, whereas the remaining amount WR is significantly reduced in the vicinity of θ = 90 °. Furthermore, there is almost no remaining in the region of 30 ° ≦ θ ≦ 85 °. This is because the injection angle θ, that is, the vector Vt indicating the transport direction of the metal wire W starting from the intersection axis P of the center axis X of the nozzle 8 and the center axis X and the surface of the metal wire W, By making the angle θ formed by, 90 ° or less, preferably 85 ° or less, it is possible to reduce the amount of hard particles and scale flakes that remain attached to the surface of the metal wire W and adversely affect the subsequent process. It is taught that it can be suppressed.

  As for the lower limit of the injection angle θ, it is necessary that θ> 0 ° in order for the slurry 9 injected from the nozzle 8 to collide with the metal wire W. Further, θ ≧ 30 ° is preferable for the slurry 9 to exert a descaling effect.

  When the plurality of nozzles 8 include a non-self-cleaning nozzle, the self-cleaning nozzle on the downstream side removes the deposit 10 generated by the injection of the slurry 9 of the non-self-cleaning nozzle. The spray region of the cleaning nozzle needs to overlap at least a part, preferably all, of the spray region of the non-self-cleaning nozzle. Therefore, when the number of nozzles 8 is small and the circumferential interval between the nozzles 8 is large, it is preferable that all of the nozzles 8 are self-cleaning nozzles. Specifically, although depending on the size of the injection region of each nozzle 8, generally, when four or less nozzles 8 are arranged at equal intervals in the circumferential direction around the metal wire W, all the nozzles 8 are It is preferable that the nozzles are self-cleaning nozzles, that is, it is preferable that the injection angles θ of all the nozzles 8 satisfy θ ≦ 90 °, and more preferably θ ≦ 85 °.

  On the other hand, when the number of nozzles 8 is large and the circumferential interval between the nozzles 8 is small, at least a part of the deposit 10 generated by the non-self-cleaning nozzle is removed by the downstream self-cleaning nozzle. It is possible. Although it depends on the width of the injection region in the circumferential direction of each nozzle 8, generally, it is a case where five or more nozzles 8 are arranged at equal intervals in the circumferential direction. When a non-self-cleaning type nozzle is included, it is on the downstream side of the non-self-cleaning type nozzle in the transport direction (the side close to the winding device 5 in FIG. 10) and is adjacent to the non-self-cleaning type nozzle in the circumferential direction. If the nozzle 8 is a self-cleaning nozzle, it is possible to remove the deposit 10 resulting from the ejection of the non-self-cleaning nozzle by the slurry 9 ejected by the self-cleaning nozzle.

  As a specific example, when the number of nozzles 8 is 5 or more and one nozzle 8 is a non-self-cleaning type nozzle, that is, when the injection angle θ exceeds 90 °, the non-self-cleaning type nozzle Even if hard particles and scale debris contained in the slurry 9 sprayed from above are scattered in the conveying direction of the metal wire W and adhere to the surface of the metal wire W to form the deposit 10, the non-self-cleaning nozzle On the other hand, if the downstream nozzles 8 adjacent to both sides in the circumferential direction are self-cleaning nozzles, that is, the injection angle θ of the nozzles 8 satisfies θ ≦ 90 ° (preferably θ ≦ 85 °). If present, both the deposit 10 generated due to the injection of the slurry 9 from the non-self-cleaning nozzle, and further the deposit 10 generated due to the slurry 9 sprayed by the self-cleaning nozzle itself are included. The self-washing It can be washed away by the jet of the slurry 9 from the mold nozzle.

  For example, when the nozzles 8A, 8B and 8C are arranged at intervals of about 60 ° in the circumferential direction of the metal wire W as shown in FIG. 7, the central nozzle 8B is a non-self-cleaning nozzle (the injection angle θ is Even if the nozzle is θ> 90 °, the nozzle 8A and the nozzle 8C adjacent to the nozzle 8B on both sides in the circumferential direction are self-cleaning nozzles (the injection angle θ is θ ≦ 90 °, preferably nozzles satisfying θ ≦ 85 °) and disposed on the downstream side of the nozzle 8B, such as hard particles or scale debris attached to the surface of the wire due to the injection of the slurry 9 of the nozzle 8B. The deposit 10 can be washed away by the slurry 9 ejected by the nozzles 8A and 8C on the downstream side. This is because the region where the slurry 9 sprayed by each nozzle 8 collides with the metal wire W, that is, the spray region on the surface of the metal wire W has a width in the circumferential direction, and therefore the circumferential interval between the nozzles 8 is small. For example, when the number of the nozzles 8 is 5 or more, the spray area of the nozzles 8A and 8C overlaps with the spray area of the nozzle 8B, and hard particles and scale debris adhered to the surface of the wire due to the nozzle 8B This is because the entire range is washed away.

  The plurality of nozzles 8 are arranged so that the injection regions of the plurality of nozzles 8 cooperate to occupy the entire 360 ° circumferential direction of the metal wire W so that the surface of the metal wire W can be uniformly descaled. But good. For example, when the six nozzles 8 are arranged at equal intervals, that is, when the six nozzles 8 are arranged at an interval of 60 ° in the circumferential direction, each nozzle 8 sprays on the surface of the metal wire W. If the region is 60 ° or more as the central angle around the axis of the metal wire W, the slurry 9 can be sprayed onto the surface of the metal wire W over the entire range of 360 °. Further, the equally spaced arrangement improves the uniformity of the surface treatment of the metal wire W.

  As described above, FIGS. 4 and 5 illustrate a spiral arrangement and a staggered arrangement for the arrangement of the nozzles 8 that also relate to the position in the transport direction. This does not impair the nozzle removal effect of the nozzle. However, as shown in FIG. 6, when all the nozzles 8 are arranged at the same position in the transport direction, that is, when there is no relative position shift between the nozzles 8 in the transport direction, the number of nozzles 8 is set. Regardless, it is preferable that all the nozzles 8 are self-cleaning nozzles, that is, the injection angle θ of all the nozzles 8 is θ ≦ 90 ° (more preferably θ ≦ 85 °).

  The hardness of the hard particles contained in the slurry 9 which is a mixture is not particularly limited, but the use of particles having a hardness higher than the hardness of the metal wire W to be processed makes it possible to improve descaling efficiency. Further, the shape and size of the hard particles are not particularly limited. However, since the surface properties of the metal wire W after the treatment are affected, it is necessary to select appropriately according to the target surface properties. The hardness, shape, and size of these hard particles do not impair the effects of the present invention and can be freely selected.

  The type of water contained in the slurry is not limited. As the water, for example, tap water and industrial water used in general industrial applications can be used. Alternatively, a rust inhibitor or the like may be added to water in order to suppress corrosion of the metal wire W.

  Further, the concentration of the slurry, in other words, the ratio of water and hard particles can be appropriately selected depending on the purpose of the treatment.

  The driving force for injecting the slurry 9 is not limited. For the injection, for example, compressed water (water jet) or compressed air can be used.

  The material of the metal wire W to be processed is not limited. The conveying speed of the metal wire is not limited. However, if the conveying speed is excessively high with respect to the number of nozzles 8, there is a possibility that a sufficient descaling effect cannot be obtained. Therefore, it is preferable that the conveyance speed is appropriately set according to the number of the plurality of nozzles 8, the ratio of the number of self-cleaning nozzles included therein, the arrangement, the jetting ability of each nozzle 8, and the like.

  The results shown in FIG. 8 are obtained by the following experiment.

  The metal wire W used in this experiment is a steel (SCM435) φ10.0 mm wire. The metal wire W is hot-rolled (→ transported), and then processed and descaled in the order of straightening, wet blasting, and water washing while being transported at a speed of 10 m / min. The blasting machine used for descaling is a general-purpose wet blasting machine manufactured by Macau Corporation. This blast machine is provided with one nozzle 8 for experiment, and this nozzle 8 can inject a slurry 9 in which abrasive grains are suspended at a compressed air pressure of 5 kgf / cm 2. The slurry 9 contains tap water and alumina # 80 abrasive grains and is suspended by mixing them. The nozzle 8 performs descaling by injecting the slurry 9 toward the metal wire W.

The residual amount of the hard particles and scale strips remaining on the metal wire W that has been descaled in this manner was measured by a measurement method including the following (1) to (4).
(1) The surface of the steel wire after the treatment is wiped with a clean waste cloth.
(2) The waste of the above (1) is ultrasonically washed in distilled water to wash away hard particles adhering to the waste.
(3) The distilled water of (2) above is filtered, the filtrate is dried, and the weight is measured.
(4) Divide the weight measured in (3) above by the surface area of the metal wire W wiped with waste cloth to obtain the residual amount per unit surface area.

  FIG. 8 shows the measurement results of the residual amount of hard particles and scale flakes measured by such a measuring method. As described above, according to FIG. 8, the center axis X of the injection of the slurry 9 from the nozzle 8 and the vector Vt indicating the transport direction starting from the intersection P between the center axis X and the surface of the metal wire W , That is, the injection angle θ is set to 90 ° or less, the hard particle residual amount WR can be reduced as much as possible, and the metal wire W can be descaled without adversely affecting the subsequent process. I understand that there is.

  Next, Example 1 according to the present invention will be described. In the first embodiment, as the metal wire W, a steel (SCM435) φ10.0 mm wire is used. This metal wire W is hot-rolled and then processed in the order of straight line straightening → wet blasting while being transported at a transport speed of 4-30 m / min determined according to the number of nozzles 8 described later. Descaled.

  A dedicated wet blasting device is used for the descaling. This dedicated wet blasting device is provided with a plurality of nozzles 8 capable of injecting slurry 9 with a compression air pressure of 5 kgf / cm 2 onto the surface of the metal wire W, and these nozzles 8 are arranged at equal intervals in the circumferential direction. The The slurry 9 contains alumina # 80 abrasive grains and tap water, and is suspended by mixing them. The plurality of nozzles 8 are arranged in a spiral shape or a zigzag shape as shown in Table 1, and are arranged so as to surround the wire over the entire circumference of 360 °.

  Drawing is performed on the metal wire W thus descaled. In this wire drawing, about 100 kg of the metal wire W, in the presence of a wire drawing powder (a combination of Kyoeisha Chemical Cosin SH-450 and a crimping roll), the wire drawing speed is 35 m / min, and the wire drawing area reduction rate is 5.9. % (Φ10.0 mm → φ9.7 mm).

  Table 1 shows the results. Legends of the wire drawing results in Table 1 are ◎, ○: drawing completed, x: burn-in occurrence. The value of the amount of die wear shown in Table 1 is a difference between values obtained by measuring the inner diameter of the drawing die with a laser measuring instrument before and after drawing, and is a relative value compared with Example 01 as 100. In particular, those with good die wear (50 or less) were marked with ◎, and others with ◯. The occurrence of seizure was determined by observing the surface of the wire after drawing with the naked eye, a magnifying glass, or palpation, and whether the surface was rough or not.

  The results shown in Table 1 show that, under the above conditions, it is possible that at least one of the plurality of nozzles 8 is a self-cleaning nozzle, which can contribute to good wire drawing, and 1) at equal intervals in the circumferential direction All the 2 to 4 nozzles 8 to be arranged are self-cleaning nozzles (that is, the injection angle θ of all the nozzles 8 is 90 ° or less), or 2) they are arranged at equal intervals in the circumferential direction. Among the five or more nozzles 8, the nozzle 8 that injects the slurry 9 at least downstream of the non-self-cleaning nozzle and adjacent to the non-self-cleaning nozzle in the circumferential direction has an injection angle θ of 90 ° or less. It is extremely effective to reduce the amount of residual hard particles remaining on the metal wire W and to implement the descaling of the metal wire W that does not adversely affect the subsequent process. It shows that there is.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. In particular, in the embodiment disclosed this time, matters that are not explicitly disclosed, for example, operating conditions and operating conditions, various parameters, dimensions, weights, volumes, and the like of a component deviate from a range that a person skilled in the art normally performs. Instead, values that can be easily assumed by those skilled in the art are employed.

Claims (10)

A method of descaling the surface of a metal wire,
Conveying the metal wire in the conveying direction along its axis;
A plurality of nozzles each capable of injecting a mixture of water and hard particles are disposed at a plurality of positions different from each other in the circumferential direction of the metal wire around the metal wire,
Scaling the surface of the metal wire by injecting a mixture of water and hard particles from the plurality of nozzles onto the surface of the metal wire, respectively,
The plurality of nozzles include a plurality of self-cleaning nozzles, and each self-cleaning nozzle sprays the mixture in a direction in which an injection angle θ is 90 ° or less, thereby generating the metal by injecting the mixture. Foreign matter generated on the surface is removed by jetting the mixture, and the jet angle θ is the center axis of the jet of the mixture from the self-cleaning nozzle and the intersection of the central axis and the surface of the metal wire. A method for descaling a metal wire, which is an angle formed by a vector indicating the transport direction as a starting point.   The metal wire descaling method according to claim 1, wherein all of the plurality of nozzles are the self-cleaning nozzles.   The metal wire descaling method according to claim 2, wherein the plurality of self-cleaning nozzles are arranged at equal intervals in the circumferential direction.   2. The metal wire descaling method according to claim 1, wherein the plurality of nozzles are a plurality of self-cleaning nozzles and a non-self-cleaning type in which the mixture is injected in a direction in which the injection angle θ exceeds 90 °. And at least one self-cleaning nozzle of the plurality of self-cleaning nozzles is disposed downstream of the non-self-cleaning nozzle in the transport direction, and the non-self with respect to the surface of the metal wire An injection region in the circumferential direction with respect to the surface of the metal wire of the at least one self-cleaning nozzle disposed at least a part of the injection region in the circumferential direction of the cleaning nozzle in the downstream side of the non-self-cleaning nozzle Descaling method of metal wire that overlaps with   5. The metal wire descaling method according to claim 4, wherein the plurality of nozzles are respectively arranged at five or more positions arranged at equal intervals in the circumferential direction, and downstream of the non-self-cleaning nozzle in the transport direction. The metal wire rod descaling method in which the non-self-cleaning nozzle and the nozzles adjacent to both sides in the circumferential direction are the self-cleaning nozzles. An apparatus for descaling the surface of a metal wire,
A transport device for transporting the metal wire in the transport direction along the axis;
Each of which is a plurality of nozzles capable of injecting a mixture of water and hard particles, and is arranged at a plurality of positions different from each other in the circumferential direction of the metal wire around the metal wire. Each of which scales the surface of the metal wire by injecting a mixture of water and hard particles onto the surface of the metal wire,
The plurality of nozzles include a plurality of self-cleaning nozzles, and each self-cleaning nozzle sprays the mixture in a direction in which an injection angle θ is 90 ° or less, thereby generating the metal by injecting the mixture. Foreign matter generated on the surface is removed by jetting the mixture, and the jet angle θ is the center axis of the jet of the mixture from the self-cleaning nozzle and the intersection of the central axis and the surface of the metal wire. A metal wire descaling apparatus having an angle formed by a vector indicating the transport direction as a starting point.   The metal wire descaling apparatus according to claim 6, wherein all of the plurality of nozzles are the self-cleaning nozzles.   The metal wire descaling apparatus according to claim 7, wherein the plurality of self-cleaning nozzles are arranged at equal intervals in the circumferential direction.   The metal wire descaling apparatus according to claim 6, wherein the plurality of nozzles are a plurality of self-cleaning nozzles and a non-self-cleaning type that injects the mixture in a direction in which the injection angle θ exceeds 90 °. At least one self-cleaning nozzle of the plurality of self-cleaning nozzles is disposed downstream of the non-self-cleaning nozzle in the transport direction with respect to the transport direction, and the non-self-cleaning type with respect to the surface of the metal wire At least a part of the injection region in the circumferential direction of the nozzle overlaps with the injection region in the circumferential direction of the at least one self-cleaning nozzle disposed on the downstream side of the non-self-cleaning nozzle with respect to the surface of the metal wire. A metal wire descaling device.   The metal wire descaling apparatus according to claim 9, wherein the plurality of nozzles are respectively arranged at five or more positions arranged at equal intervals in the circumferential direction, and are downstream of the non-self-cleaning nozzle in the transport direction. And a non-self-cleaning nozzle and a nozzle adjacent to both sides in the circumferential direction are the self-cleaning nozzles.