Method for manufacturing rolled or drawn metal wire

Abstract

The present invention generally relates to a method for manufacturing a drawn or a rolled metal wire. The method makes it possible to effectively clean or strip the metal wire and subsequently to draw or roll the wire, optionally followed by further adjustments, and finally to wind it up again. More particularly, the present invention provides a method for manufacturing a drawn or rolled metal wire, comprising: • (a) arranging a rod wire having a diameter of between 4.0 mm and 22.0 mm, the rod wire being provided on a roll with a cast of between 600 mm and 5,000 mm; • (b) stripping the rod wire by means of a stripping device, the stripping device comprising: • a first set of at least two rotating wheels, wherein the rotating wheels are arranged in such a way that the rod wire follows an S-shaped course, and • at least one rotor provided with at least one cleaning pad, wherein the rotor is configured to rotate about the rod wire, and wherein the at least one cleaning pad is in contact with the rod wire in order thus to brush across the outer layer of the rod wire; • (c) applying a lubricant onto the surface of the stripped rod wire and wherein the lubricant is applied to the surface of the rod wire before said rod wire is drawn or rolled, so that the wire drawing or rolling is performed on a lubricated rod wire; (d1) wire drawing said rod wire by means of at least one wire drawing device comprising the combination of a drawing die holder and a capstan, and / or (d2) wire rolling said rod wire by means of at least one rolling head, wherein a lubricant may be applied for each rolling head; • (e) passing the drawn or rolled metal wire through a return wheel and / or a wire straightener, wherein the wire straightener consists of at least three wheels; and • (f) preferably winding up the drawn or rolled metal wire onto a coil by means of a winding device, wherein a wire guide is positioned in front of the winding device.

Description

FIELD OF THE INVENTION

[0001] The present invention relates to a method for drawing or rolling metal wires. The drawn or rolled wires are used, inter alia, in the manufacture of nails, both individual nails and interconnected nails, and woven or welded wire structures, (pig) slats or architectural slats or other wire applications.BACKGROUND OF THE INVENTION

[0002] Metal wire is an important raw material in the industrial sector and the building sector. However, in order to be usable, the wires have to meet certain properties. Thus, the wires not only have to be sufficiently deformable and achieve a sufficiently high tensile stress, but for certain applications, the surface has to be sufficiently pure.

[0003] In order to obtain metal wires having these desired properties, the initial selection of the metal wire with a certain carbon content is important and the wires typically have to undergo different processing steps as part of the production process, such as cleaning, rolling or wire drawing and optionally subsequent elongation and straightening. Sometimes, it is also important to determine the equivalent carbon content, to ensure that the wire is readily weldable.

[0004] In the production process of metal wires, various means and ways are already known for cleaning or stripping the metal wire. Mechanical cleaning is highly effective and is often preferred to chemical cleaning processes because chemical cleaning processes often require the use of highly toxic agents in order to clean the metal wire. In addition, chemical cleaning is generally also more expensive. Systems for effecting a mechanical cleaning of the metal wire are also already known. These systems generally use for example steel wool, sandpaper or other abrasive means which are pushed against the metal wire at a predetermined pressure. When the metal wire moves along these abrasive parts, the oxide particles or other impurities which cover the metal wire are removed and the metal wire is cleaned effectively.

[0005] An alternative way of removing the oxide particles or other impurities covering the metal wire is the use of bending rollers. In this case, the metal wire is conducted along the bending rollers, resulting in the metal wire being bent in various locations. The bending procedure will lead to cracks in the mill scale which is composed of the oxide particles and / or other impurities, following which this broken mill scale will fall off the metal wire.

[0006] Drawing or rolling metal wire is a shaping technique in which a metal wire is elongated. Typically, there are two types of elongation. With elastic elongation, the metal wire is subjected to loads within its limit of elasticity. The elongation is cancelled when the load is removed. The value of the elastic elongation depends on the metal wire and the tensile strength, but is approximately 0.20% under normal conditions. Plastic elongation is permanent and occurs when the load exceeds the limit of elasticity. Plastic elongation of metal wire is carried out by means of generally known techniques and, for example, by guiding the metal wire across various rotating axles. It may also be achieved by drawing the wire through a drawing die and lastly it may also be achieved by means of a rolling head. In this case, the wire is drawn through a set of moulding rollers, resulting in the section of the wire changing and reducing.

[0007] The wire may have a round section or any other desired section, such as for example a triangular section. In recent years, many improvements have been made with regard to the methods and apparatuses which are used for the individual processing steps within the production process of metal wire. However, there is still a significant amount of room for improvement, in particular with regard to producing premium metal wires where the cleaning of the outer layer of the metal wire, the correct reduction of the wire diameter, and the accurate realisation of the desired strength properties form part of an efficient and high-quality production process. In particular, it is a challenge to be able meet stringent quality standards concerning wire diameter, strength and shape of the resulting wire, while simultaneously being able to use a simple production process and inexpensive grades of steel.

[0008] In view of the above, there remains a need in the field for improvements with regard to the production process for producing metal wires.SUMMARY OF THE INVENTION

[0009] The present invention generally relates to a method for manufacturing a drawn or a rolled metal wire. The method makes it possible to effectively clean or strip the metal wire and subsequently to draw or roll the wire, optionally followed by further adjustments, and finally to wind it up again.

[0010] More particularly, the present invention provides a method for manufacturing a drawn or rolled metal wire, comprising: (a) arranging a rod wire having a diameter of between 4.0 mm and 22.0 mm, the rod wire being provided on a roll with a cast of between 600 mm and 5,000 mm; (b) stripping the rod wire by means of a stripping device, the stripping device comprising: a first set of at least two rotating wheels, wherein the rotating wheels are arranged in such a way that the rod wire follows an S-shaped course, and at least one rotor provided with at least one cleaning pad, wherein the rotor is configured to rotate about the rod wire, and wherein the at least one cleaning pad is in contact with the rod wire in order thus to brush across the outer layer of the rod wire; (c) applying a lubricant onto the surface of the stripped rod wire and wherein the lubricant is applied to the surface of the rod wire before said rod wire is drawn or rolled, so that the wire drawing or rolling is performed on a lubricated rod wire; (d1) wire drawing said rod wire by means of at least one wire drawing device comprising the combination of a drawing die holder and a capstan, and / or (d2) wire rolling said rod wire by means of at least one rolling head, wherein a lubricant may be applied for each rolling head; (e) passing the drawn or rolled metal wire through a return wheel and / or a wire straightener, wherein the wire straightener consists of at least three wheels; and (f) preferably winding up the drawn or rolled metal wire onto a coil by means of a winding device, wherein a wire guide is positioned in front of the winding device.

[0011] In step (d1), the wire drawing is performed using one or more wire drawing devices, wherein a wire drawing device comprises a combination of a drawing die holder and a capstan. In this case, lubricant is preferably applied for at least one combination of drawing die holder and capstan. When several combinations of wire drawing die holder and capstan are provided, preferably no lubricant is applied for the last combination of wire drawing die holder and capstan in order to prevent an excessive amount of soap from being provided on the drawn or rolled metal wire. In order to ensure that the residual soap on the drawn or rolled metal wire is as low as possible, preferably no lubricant is applied for the last two combinations of wire drawing die holder and capstan.

[0012] The final wire diameter of the drawn or rolled metal wire is between 2.0 mm and 20.5 mm, wherein the metal wire is provided on a roll with a cast of between 400 mm and 10,000 mm and a helix of at most 200 mm.

[0013] Preferably, the rod wire is wound onto a rod wire bundle, in which case the rod wire is fitted via at least two vertical or horizontal towers, and wherein a rod wire bundle is in each case fitted to a vertical or horizontal tower, so that the end of a first rod wire bundle may be coupled to the start of a second rod wire bundle, preferably via welding the ends together, in order thus to achieve uninterrupted fitting of rod wire.

[0014] Preferably, the rod wire consists of a low-carbon steel, preferably from the types of metal SAE 1004 to SAE 1020, and wherein the silicium content in the rod wire contains at most 0.03% Si or wherein the Si content is at least 0.14%. Providing a rod wire having these silicium contents will ensure that the metal wire can be galvanized in an optimum manner.

[0015] Preferably, the diameter of the drawn or rolled metal wire is between 2.0 and 20.0 mm. More preferably, the diameter of the drawn or rolled metal wire is between 2.07 mm and 2.17 mm, preferably between 2.40 mm and 2.55 mm, between 2.70 mm and 2.90 mm and between 2.90 and 3.20 mm, between 3.25 mm and 3.50 mm, between 3.60 and 3.75 mm, between 3.90 mm and 4.15 mm, between 4.40 mm and 4.90 mm, or between 4.90 mm and 5.90 mm, or between 5.90 and 6.10 mm, or between 6.10 and 7.20 mm, or between 7.20 and 8.20 mm, or between 8.20 and 10.20 mm, or between 10.20 and 12.30 mm, or between 12.30 and 14.50 mm, or between 14.50 and 20.50 mm. The diameter has a tolerance of + / - 0.020 mm, or + / - 0.030 mm, or + / - 0.040 mm, or + / - 0.060, or + / - 0.10 mm, or + / - 0.50 mm.

[0016] Depending on the diameter, the rolled or drawn metal wire preferably has a tensile strength in accordance with the following table: Diameter (mm)Tensile strength (N / mm 2< ) lower limitTensile strength (N / mm 2< ) upper limit2.0 - 3.07009503.0 - 4.06509004.0 - 5.05508305.0 - 20.0550700

[0017] Preferably, the rod wire will heat up during the step of stripping the rod wire.

[0018] Preferably, the at least two rotating wheels are arranged so as to be movable, and wherein the positions of the rotating wheels are adjustable with respect to each other in order thus to be able to modify the S-shaped course.

[0019] Preferably, the rotating wheels are mounted on a movable background disc, wherein the background disc is configured in such a way that the position of the background disc will determine the S-shaped course. Depending on the position of the rotating wheels relative to each other, the rotating wheels can bring about a first reduction of the rod wire.

[0020] Preferably, the stripping device furthermore consists of a second set of rotating wheels, the second set of rotating wheels consists of at least three wheels, wherein the rotation axles of the wheels of the first set are essentially arranged horizontally and the rotation axles of the three wheels of the second set are essentially arranged vertically.

[0021] Preferably, the stripping device furthermore consists of at least one helical brush, wherein the at least one helical brush is preferably arranged after the at least one rotor and / or before the application of the lubricant on the surface of the stripped rod wire. Preferably, the at least one helical brush is arranged in a swinging manner and / or the at least one helical brush is capable of performing a pulsating and / or vibrating movement. Preferably, a linear motor or a pneumatic cylinder is provided which brings about the pulsating and / or vibrating movement of the at least one helical brush.

[0022] Preferably, the stripping device consists of at least two rotors, and wherein the rotors rotate in the same direction or wherein the rotors rotate in an opposite direction.

[0023] Preferably, the stripping device furthermore consists of at least one support means to support the rod wire at the location of the at least one rotor in order thus to compensate for the pushing forces of the at least one cleaning pad on the rod wire. When the at least one cleaning pad is being pushed against the rod wire in order to clean the metal wire efficiently, it is possible that the rod wire may be pushed sideways if the pushing force of the cleaning pad is excessively high. By using a support means which will form a wall as it were against which the rod wire will be displaced, the rod wire will only experience a limited displacement due to the pushing force of the cleaning pad, thus resulting in an improved cleaning action of the at least one cleaning pad. Preferably, the at least one cleaning pad is provided with a plurality of metal wires which are contained in a synthetic polymer along substantially the entire length. Furthermore, the at least one cleaning pad is preferably tubular, oval, beam-shaped or cube-shaped. Preferably, the at least one cleaning pad is provided with an indentation, preferably along the entire length of the at least one cleaning pad, wherein the rod wire is passed through the indentation, and wherein the at least one cleaning pad cleans the rod wire and supports it during cleaning. By making use of an indentation, it will be possible to pass the rod wire as it were between the metal wires which are contained in the synthetic polymer, as a result of which virtually the entire circumference of the rod wire will be cleaned by the cleaning pad.

[0024] Preferably, the lubricant provided in step (c) is an emulsion, wherein the emulsion is introduced in a tubular duct, and wherein the rod wire is passed through the tubular duct during application of the emulsion in order thus to provide the rod wire with emulsion on all sides. Preferably, the lubricant is a soap, with the active component of the soap mainly containing calcium stearate or sodium stearate, or containing a combination of calcium stearate and sodium stearate.

[0025] In addition, preferably no soap is used in the last drawing die.

[0026] Preferably, the step of wire drawing or rolling of the rod wire will produce a reduction in the diameter of the metal wire of 5.0% to 40.0% when the rod wire moves through a first wire drawing device. During optional subsequent steps, the rod wire may be reduced further, again with a reduction of 5.0% to 40.0% per step. In an alternative embodiment, an equal reduction in the diameter of the rod wire will in each case be obtained every time the rod wire moves through successive wire drawing devices during the drawing step of the rod wire. In a likewise alternative embodiment, a continuously decreasing reduction in terms of percentage of the diameter of the metal wire will in each case be obtained during the drawing step of the rod wire. In a likewise alternative embodiment, an adjusted decrease in the reduction in terms of percentage of the diameter of the rod wire will in each case be obtained during the drawing step of the rod wire, in order to ensure that the power consumption should be the same at every step.

[0027] Preferably, at least one wire drawing device consists of a rotating drawing die holder and a wire drawing die. The wire drawing die may be cooled either directly or indirectly. Preferably, the wire drawing die is cooled indirectly, with the cooling being an internal cooling in the wire drawing die, so that the rod wire is cooled by the wire drawing die while it moves. In this way, it will be possible to reduce the diameter of the rod wire, while the drawing process is preferably carried out at a temperature below the recrystallization temperature of the metal. Cold-drawing typically results in an increase in the tensile strength of the metal wire. Preferably, the at least one wire drawing device is provided with a pressure set, so that the pressure set can increase the pressure on the soap, in order thus to support the passage of the rod wire and lubricant through the wire drawing die.

[0028] Preferably, the lubricant used between every wire drawing device is the same lubricant.

[0029] In an alternative embodiment, the lubricant used between every wire drawing device is different.

[0030] Preferably, the lubricant used and applied before the first wire drawing device is a soap substantially consisting of calcium stearate, and the lubricant used between every wire drawing device is a soap substantially consisting of sodium stearate.

[0031] Preferably, the lubricant used for the last wire drawing device is an emulsion soap; or preferably no soap is used in order thus to obtain a purer surface.

[0032] Preferably, the lubricant used between every combination of wire drawing die holder and capstan is lubricant.

[0033] Preferably, the lubricant used between every combination of wire drawing die holder and capstan is different, and preferably the lubricant used and applied before the first wire drawing device is a soap substantially consisting of calcium stearate, for every intermediate wire drum (70), the lubricant used is a soap substantially consisting of sodium stearate, and for the last wire drawing device the lubricant used is an emulsion soap.

[0034] Preferably, the wire in the last drawing die step is not provided with soap.

[0035] Preferably, the wire straightener comprises at least 3 wheels. Preferably, the wire straightener comprises at most 20 wheels.

[0036] Preferably, the wire straightener consists of a first part provided with at least three wheels and a second part provided with at least three wheels. The rotation axles of the three wheels of the first part are arranged horizontally, and the rotation axles of the three wheels of the second part are arranged vertically.

[0037] Preferably, the method comprises passing the drawn or rolled metal wire through a wire straightener, wherein the wire is depressed up to a depression depth by the respective wheels of the wire straightener. For example, the wire straightener comprises one or more sets of wheels. For example, in one or more sets of wheels of the wire straightener, the depression depth of each of the wheels is at most 5 mm, for example at most 4 mm, for example at most 3 mm, for example at most 2 mm, for example at most 1 mm, so that the respective set is set as a straightener. For example, in one or more sets of wheels, the depression depth of at least one of the wheels is at least 2 mm, for example at least 3 mm, for example at least 4 mm, for example at least 5 mm, for example at least 6 mm, so that the respective set is set as a softener. For example, the depression depth of each of the wheels of the wire straightener is at most 15 mm, for example at most 10 mm.

[0038] Preferably, at least one of the wheels of the wire straightener is arranged so as to be movable, so that the depression depth of the metal wire can be varied by displacing the one or more movable wheels.

[0039] Preferably, the depression depth of the movable wheels of the wire straightener is adjusted on the basis of one or more wire parameters. For example, the one or more wire parameters are characteristic of the initial wire at the start of the production process, and / or are characteristic of the desired wire at the end of the production process. For example, the one or more wire parameters are characteristic of the desired strength or softness of the metal wire.

[0040] Preferably, the wire straightener is cooled. For example, a cooling duct is arranged in each wheel of the wire straightener, extending along the rotation axle of the wheel and adapted for passing through a cooling agent, for example water. For example, the wire straightener is surrounded by a housing, and a cooling agent, for example air, is passed through the housing.

[0041] Preferably, the residual lubricant content of the applied lubricant after winding up the drawn or rolled metal wire is at most 3.0 g / m 2< wire surface, for example at most 1.5 g / m 2< , for example at most 0.5 g / m 2< .

[0042] Preferably, the wire section of the metal wire has a round or triangular shape. Preferably, the metal wire has a round shape. Preferably, the metal wire has a triangular shape, wherein, more preferably, at least one of the 3 sides has a profiled surface.

[0043] In an additional embodiment according to the invention, a metal wire is manufactured using one of the above preferred methods.

[0044] These and further aspects and embodiments of the invention are explained in more detail in the following chapters and in the claims and are also illustrated by means of non-limiting examples.BRIEF DESCRIPTION OF THE FIGURES

[0045] Fig. 1 diagrammatically illustrates a specific embodiment of the method described herein. Fig. 2 diagrammatically shows the metal wire which is wound on a rod wire bundle and placed on vertical towers. Fig. 3 diagrammatically shows a stripping device, wherein a first set of rotating wheels is provided, so that the metal wire can be guided along the rotating wheels in an S-shaped course. Fig. 4 diagrammatically shows a second set of rotating wheels of the stripping device. Fig. 5 shows a helical brush which is arranged in a swinging way, so that it can make a pulsating and vibrating movement. Fig. 6 shows a rotor of the stripping device, in which cleaning pads are provided. Fig. 7A shows a first embodiment of the cleaning pads, Fig. 7B shows an alternative embodiment of the cleaning pads. Fig. 8 shows a first soap box provided with lubricant for applying a lubricant to the surface of the stripped metal wire and a first drawing die unit for drawing the metal wire. Fig. 9 shows a second soap reservoir and a drawing die unit, followed by a wire drum for drawing the metal wire onwards. Fig. 10 shows an emulsion reservoir for applying the emulsion on the circumference of the metal wire, before the metal wire undergoes its final elongation. Fig. 11 shows, as an alternative of the wire drawing, a rolling head. Fig. 12 shows a wire straightener and a return wheel device for straightening the drawn or rolled metal wire. Fig. 13 shows a set of wheels of a wire straightener. Fig. 14 shows a detail of the set from Fig. 13. Fig. 15 shows the set from Fig.13 and illustrates how the wire straightener has been provided with cooling ducts. Fig. 16 shows a wire guide and the coil for winding up the drawn metal wire. DETAILED DESCRIPTION OF THE INVENTION

[0046] Before describing the present method and the devices which are used in the invention, it should be understood that this invention is not limited to specific described methods, components or devices, since such methods, components and devices may obviously vary. It should also be understood that the terminology used herein is not intended to limit, since the operating area of the present invention will only be limited by the attached claims.

[0047] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is generally understood by a person skilled in the art to which this invention appertains. Although in practice or when testing the present invention, it is possible to use all methods and materials which are similar to or equivalent to those described herein, the methods and the materials which are preferred will now be described.

[0048] As used herein, the singular forms "a", "an" and "the" include both the singular and the plural of the term referred to unless the context clearly indicates otherwise.

[0049] The terms "comprising" and "comprises" as used herein are synonymous with "including", "containing" or "contains", and are inclusive or open and do not exclude any additional, unmentioned parts, elements or method steps.

[0050] The terms "comprising" and "comprises" also include the term "consisting of".

[0051] The definition of numeric ranges by means of end points comprises all numbers and fractions which fall within the respective ranges, as well as said end points.

[0052] The term "approximately" as used herein when referring to a measurable value, such as a parameter, an amount, a time period and the like, shall comprise variations of + / -10% or less, preferably + / - 5% or less, more preferably + / - 1% or less, and still more preferably + / - 0.1% or less of the specified value, in so far as such variations apply to the disclosed invention. It should be understood that the value to which the definition "approximately" refers is itself also specific and is preferably disclosed.

[0053] All documents which are cited in the present specification are hereby incorporated in their entirety.

[0054] Unless defined otherwise, all terms used in the disclosure of the invention, including technical and scientific terms, have the meaning as is generally understood by a person skilled in the art to which this invention appertains. As a further aid, definitions of the terms which are used in the description are included so as to better be able to appreciate the principles of the present invention.

[0055] In general, the present invention provides a method for manufacturing a drawn or rolled metal wire. In this case, the method will adjust, and preferably reduce, the diameter of a metal wire after the metal wire has been cleaned or stripped. After the drawn or rolled metal wire has been straightened, the metal wire will furthermore preferably be wound onto a coil, so that the drawn or rolled metal wire can be handled easily.

[0056] Wire drawing is a process in which the diameter of a thick metal wire is reduced by drawing it through one or more drawing dies. The drawing dies have a wire drawing opening which is smaller than the diameter of the metal wire, thus reducing the diameter of the metal wire by means of wire drawing.

[0057] Rolling is a shaping technique in which a metal wire is deformed by two or more rollers. Rolling a metal wire may be used to change the cross section of the wire and / or to provide a profile on the wire surface or to give the wire a special shape.

[0058] Plastic elongation is a shaping technique in which a metal wire is elongated permanently by subjecting it to a load in excess of its limit of elasticity.

[0059] More particularly, the present invention provides a method for manufacturing a drawn or rolled metal wire, comprising: (a) arranging a rod wire having a diameter of between 4.0 mm and 22.0 mm, preferably wherein the rod wire is provided on a roll with a cast of between 600 mm and 5,000 mm; (b) stripping the rod wire by means of a stripping device, the stripping device comprising: a first set of at least two rotating wheels, wherein the rotating wheels are arranged in such a way that the rod wire follows an S-shaped course, and at least one rotor provided with at least one cleaning pad, wherein the rotor is configured to rotate about the rod wire, and wherein the at least one cleaning pad is in contact with the rod wire in order thus to brush across the outer layer of the rod wire; (c) applying a lubricant onto the surface of the stripped rod wire and wherein the lubricant is applied to the surface of the rod wire before said rod wire is drawn or rolled, so that the wire drawing or rolling is performed on a lubricated rod wire; (d1) wire drawing said rod wire by means of at least one wire drawing device comprising the combination of a drawing die holder and a capstan, and / or (d2) wire rolling said rod wire by means of at least one rolling head, wherein a lubricant may be applied for each rolling head; (e) passing the drawn or rolled metal wire through a return wheel and / or a wire straightener, wherein the wire straightener consists of at least three wheels; and (f) preferably winding up the drawn or rolled metal wire onto a coil by means of a winding device, wherein a wire guide is positioned in front of the winding device.

[0060] This method will be explained in more detail below.

[0061] The method described herein is particularly suitable for drawing or rolling a metal wire in a continuous manner. In this case, the metal wire is conveyed along a predetermined route in a continuous manner, preferably at a speed in the range from approximately 10 m / min to approximately 1200 m / min, more preferably at a speed in a range from approximately 50 m / min to approximately 800 m / min, and most preferably at a speed in a range from approximately 400 m / min to approximately 700 m / min. The conveying speed of the metal wire may be, for example, approximately 100 m / min, approximately 125 m / min, approximately 150 m / min, approximately 175 m / min, approximately 200 m / min, approximately 250 m / min, approximately 300 m / min, approximately 350 m / min, approximately 400 m / min, approximately 450 m / min, approximately 500 m / min, approximately 550 m / min, approximately 600m / min, approximately 650 m / min, or approximately 700 m / min. Since the diameter of the metal wire is being reduced in the present method, there is a difference between the speed of the metal wire for the drawing process or rolling process and the speed of the metal wire after the drawing process or rolling process. In this case, the difference in speed corresponds to the degree of lengthening of the wire. Thus, an incoming speed of 60 m / min with a lengthening of the wire of between 5% and 20% will result in a respective outgoing speed of 63 m / min and 75 m / min, an incoming speed of 120 m / min with a lengthening of the wire of between 5% and 20% will result in a respective outgoing speed of 126 m / min and 150 m / min. An incoming speed of 600 m / min and a lengthening of the metal wire of between 5% and 20% will result in a respective outgoing speed of 630 m / min and 750 m / min.

[0062] In a continuous process, the conveying speed of the metal wire remains virtually constant during each step of the process. The person skilled in the art will understand that due to the lengthening of the wire, the speed at which the metal wire is being conveyed expressed in weight unit per unit time typically remains constant, whereas the speed expressed in length unit per unit time may vary between the various steps of the process.

[0063] As used herein, the term "in-line" is understood to mean that the metal wire moves through the various steps of the method in a continuous manner. In other words, the various steps are performed simultaneously or successively without a noticeable delay. An "in-line" step of the method implies that the step is a part of the continuous method.

[0064] In a first step (a) of the method according to the present invention, a rod wire is provided. The rod wire may be provided on a roll or rod wire bundle. In certain embodiments, step (a) thus comprises the unwinding of a rod wire from a rod wire bundle, in which case the supply of the rod wire takes place via at least two vertical or horizontal towers, and in which case a rod wire bundle is placed on a vertical or horizontal tower in each case, so that the end of a first rod wire bundle can be coupled to the start of a second rod wire bundle, preferably by welding the ends to each other in order thus to produce an uninterrupted supply of rod wire.

[0065] Preferably, the rod wire consists of a low-carbon steel, preferably from the types of metal SAE 1004 to SAE 1020, and wherein the silicium content in the rod wire contains at most 0.03% Si or wherein the Si content is at least 0.14%. Providing a rod wire having these silicium contents will ensure that the metal wire can be galvanized in an optimum manner.

[0066] The rod wire provided in step (a) is, for example, a hot-rolled rod wire, preferably a metal wire consisting of a low-carbon steel, such as the types of metal SAE 1004 to SAE1020, preferably SAE 1006 to SAE 1010, wherein the silicium content in the metal wire is at most 0.03% or is at least 0.14%.

[0067] Preferably, the rod wire which is provided in step (a) is a smooth rod wire.

[0068] The rod wire may have any cross section, such as a round, square, rectangular, oval or semi-oval cross section. The rod wire according to the present invention may be chosen within a wide range of diameters which is between 4.0 mm and 22.0 mm, preferably between 4.0 mm and 16.0 mm and more preferably between 4.0 mm and 6.0 mm.

[0069] For wires having a noncircular cross section and / or a profiled surface, the term "diameter" as used herein denotes an equivalent diameter, more particularly on the basis of the wire weight of a theoretical smooth wire.

[0070] The metal wire is made from one or more metal or metal alloys, in a preferred embodiment, the wire is a steel or iron wire. Steel wires may be made from steel, preferably having a low-carbon content.

[0071] The method described herein comprises, in a step (b), the (in-line) stripping of the rod wire obtained in step (a), as described above. The stripping or cleaning of the rod wire is carried out by means of a stripping device. The stripping of the rod wire may be performed by means of various substeps in order thus to obtain a surface which is cleaned or stripped in as optimal a manner as possible. The stripping is preferably performed before the wire drawing or the rolling of the rod wire. The stripping entails the removal of any mill scale from the rod wire. Mill scale is a type of oxidation which is created during the production of new hot-rolled steel. The oxidation layer usually has a thickness of between 2 to 500 micrometres, depending on the rolling conditions of the steel. The presence of mill scale on the rod wire is usually undesirable because it can adversely affect the processing of the wires. Thus, the presence of mill scale may render welding of the wires more difficult, and mill scale breaking loose during the wire drawing process may cause damage to the equipment used in the process. Removal of the mill scale and any impurities on the surface of the rod wire may be effected in a mechanical or chemical way. Mechanical means to remove the mill scale may comprise, but are not limited to deforming, brushing, and / or abrasive blasting (such as sandblasting) of the rod wire. In a preferred embodiment, the mill scale is removed by (reversible) deformation of the wire. This is known to the person skilled in the art and based on the principle that the rod wire is typically flexible, whereas the mill scale is brittle. A sufficient degree of deformation (for example bending, torsion, and / or elongation) of the rod wire thus results in the mill scale breaking, as a result of which it will fall from the rod wire. This may be done in a continuous way, for example by bending the rod wire over a coil or rotating wheel. Stripping the rod wire according to the present invention is preferably effected by means of a first set of at least two rotating wheels or coils, wherein the rotating wheels are arranged in such a way that the rod wire follows an S-shaped course. Due to the fact that the rod wire is conducted over the rotating wheels via an S-shaped course, the rod wire will be bent in various locations of the S-shaped course. Due to these bends, the mill scale will have cracks, the mill scale will break and the mill scale will, at least partly, fall off the wire. Preferably, the at least two rotating wheels or coils are arranged so as to be movable, with the position of the rotating wheels or coils with respect to each other being adjustable. If the position of the rotating wheels or coils has been adapted, the S-shaped course will follow a different trajectory, resulting in the rod wire being bent in a different way. Preferably, the rotating wheels are mounted on a movable background disc, and the background disc is configured in such a way that the position of the background disc will determine the S-shaped course. Preferably, the mutual positions of the rotating wheels of the first set of the stripping device are continuously adjustable, as a result of which the S-shaped course will have a continuously changing trajectory and the curvature of the rod wire will always change slightly. As a result thereof, the mill scale will be broken up in a more effective manner and the amount of mill scale which is removed by the first set of rotating wheels of the stripping device will increase. During the step of stripping the rod wire, and mainly by the bending operation and the movement of the rod wire about the rotating wheels or coils, the rod wire will warm up. In addition, it is possible that, due to the position of the rotating wheels or coils with respect to each other, a first reduction of the diameter of the rod wire will be achieved.

[0072] In addition, it is possible that the stripping device also consists of a second set of rotating wheels, wherein the second set of rotating wheels consists of at least three rotating wheels or coils (or again consists of such a disc with 2 rotation axles). The rotation axles of the wheels of the first set are essentially arranged horizontally, and the rotation axles of the wheels of the second set are essentially arranged vertically. Due to the fact that the rotation axles of the wheels of the second set differ from the rotation axles of the first set, the bending to which the rod wire is subjected will change and will promote breaking of the mill scale. Another arrangement of the rotation axles of both the first and the second set is also possible.

[0073] In addition, the step (b) described herein provides at least one rotor provided with at least one cleaning pad. The rotor is configured to rotate about the rod wire. In this case, the at least one cleaning pad will be brought into contact with the rod wire in order thus to brush across the outer layer of the rod wire. Preferably, several cleaning pads are provided, with each cleaning pad being provided with a plurality of metal wires, for example small steel wires which are contained in a synthetic polymer, such as rubber, along substantially their entire length. By providing a synthetic polymer, such as rubber, into which the small steel wires are cast, the rod wire will take more time in finding a way through the small steel wires and will be cleaned more thoroughly in the process. Preferably, the at least one cleaning pad is tubular, oval, beam-shaped or cube-shaped. When use is made of a cleaning pad which has an elongate shape, the rod wire will be in contact with the cleaning pad for a longer period of time. As a result thereof, the rod wire will not develop a fold as quickly, as a result of which it is easier to clean and the efficiency of the other cleaning pads is maintained. In addition, it is possible to provide the at least one cleaning pad with an indentation, preferably along the entire length of the cleaning pad, with the rod wire being passed through the indentation. In this way, the pressure force which is applied to the rod wire by the cleaning pad will be distributed more evenly and the rod wire to be cleaned will be more effectively encapsulated and supported during cleaning.

[0074] If desired, it is possible to provide the stripping device with at least two rotors. The rotors may optionally rotate in the same direction or in an opposite direction.

[0075] In specific embodiments, the stripping device may furthermore consist of at least one helical brush and with the at least one helical brush preferably being arranged after the at least one rotor and / or before the application of the lubricant to the surface of the stripped metal wire. It is likewise possible to arranged a helical brush before the at least one rotor and after the first and second set of at least two rotating wheels. The helical brushes are preferably arranged in a swinging way. Preferably, they may also make a pulsating and / or vibrating movement, optionally in combination with the swinging arrangement. Preferably, a linear motor or a pneumatic cylinder causes the pulsating and / or vibrating movement of the at least one helical brush.

[0076] In a specific embodiment, the stripping device furthermore consists of at least one support means to support the rod wire at the location of the at least one rotor and thus to compensate for the pushing forces of the at least one cleaning pad on the rod wire and to maintain the wire in position. When the at least one cleaning pad is pushed against the rod wire in order thus to clean the metal wire efficiently, it is possible that the rod wire may be pushed sideways on account of the pushing force of the cleaning pad. By using a support means which will form a guide as it were against which or inside which the rod wire will be displaced, the rod wire will only experience a limited displacement due to the pushing force of the cleaning pad, thus resulting in an improved cleaning action of the at least one cleaning pad.

[0077] The method described herein comprises, in a step (c), the (in-line) application or coating of the rod wire. More particularly, the rod wire may be provided with a lubricant. This may be used to assist the wire drawing process or the rolling process and the possible stress relief. Suitable lubricating means are well-known to the person skilled in the art. In specific embodiments, the wire is provided with a drawing soap, with the active component of the soap mainly being calcium stearate, sodium stearate, or a combination of calcium stearate and sodium stearate. Preferably, the wire is provided with a lubricant before rolling or wire drawing the rod wire. The lubricant may be applied in a continuous manner by spraying, submerging, brushing, or other techniques which are known to the person skilled in the art.

[0078] The method described herein, in a step (d), comprises the (in-line) wire drawing or rolling of the rod wire. In this case, a drawn or rolled metal wire is obtained which may optionally be treated further (see below). Wire drawing processes or rolling processes for metal wires are well-known to the person skilled in the art. An elongation process may be performed by guiding the rod wire across at least two drawing rollers, with the second drawing roller having a diameter which is slightly larger than that of the first drawing roller, as a result of which the wire is subjected to plastic elongation. The difference in diameter causes tension on the rod wire.

[0079] Sometimes, the desired deformation can be achieved more easily by drawing the wire through at least one drawing die, or by rolling the wire through a set of rollers. When more than one wire drawing device is provided, lubricant will preferably be applied between every wire drawing device. The lubricant may in each case be the same lubricant or a different lubricant may be used for each wire drawing device. Preferably, the lubricant used and applied before the first wire drawing device will be a soap substantially consisting of calcium stearate, for every intermediate wire drawing device, the lubricant used will be a soap substantially consisting of sodium stearate, and for the last wire drawing device, the lubricant used will be an emulsion soap. In the case of an emulsion soap, the emulsion will be introduced in a tubular duct. As part of the application of the emulsion, the rod wire will be passed through the tubular duct in order thus to provide the rod wire with the emulsion on all sides. Preferably, it is possible not to use any soap during the last reduction step using a drawing die.

[0080] According to a preferred embodiment, the wire drawing device consists of a rotating drawing die holder and a drawing die. The drawing die may be cooled both directly and indirectly. The drawing die is cooled indirectly by rotation of the drawing die holder, in which case the cooling will cause an internal cooling in the drawing die. As a result thereof, the rod wire is cooled while moving through the drawing die. Preferably, the at least one wire drawing device is provided with a pressure set, so that the pressure set can build up additional pressure in order thus to support passing the rod wire and lubricant through the drawing die.

[0081] In a preferred embodiment, the method described herein is a method for cold-drawing a rod wire. In this case, the elongation process is carried out at a temperature below the recrystallization temperature of the metal. More particularly, the elongation process can be carried out at room temperature. Cold-drawing typically results in an increase of the tensile strength of the rod wire. In addition, during the step (d), a reduction in the diameter of the rod wire of 5 to 40% will be achieved when the rod wire moves through a first wire drawing device. Alternatively, it is possible that during the step (d) of wire drawing the rod wire, in each case an identical reduction in the diameter of the rod wire is achieved each time the rod wire moves through successive wire drawing devices. As an additional alternative, it is possible that, during the step (d) of the wire drawing of the rod wire, in each case a continuously decreasing reduction in terms of percentage of the diameter of the rod wire is obtained in each case when the rod wire moves through successive wire drawing devices.

[0082] The result of the elongation of the rod wire by the at least one wire drawing device is that a drawn or rolled metal wire is obtained, wherein the diameter of the drawn or rolled metal wire is preferably between 2.07 mm and 2.17 mm, preferably between 2.4 mm and 2.55 mm, between 2.7 mm and 2.9 mm and between 2.9 and 3.20 mm, between 3.25 mm and 3.5 mm, between 3.6 and 3.75 mm, between 3.90 mm and 4.15 mm, between 4.4 mm and 4.9 mm, or between 4.9 mm and 5.9 mm, or between 5.9 and 6.1 mm or between 6.1 and 7.2 mm or between 7.2 and 8.2 mm or between 8.2 and 10.2 mm, or between 10.2 and 12.3 mm or between 12.3 and 14.5 mm or between 14.5 and 20.5 mm, with the diameter having a tolerance of + / - 0.02 mm, + / - 0.03 mm or + / - 0.04 mm or + / - 0.06 or 0.1 mm or + / - 0.5 mm. Preferably, using the method, a metal wire is obtained, with the drawn or rolled metal wire with a certain diameter having a tensile strength which falls into a certain class: Diameter (mm)Tensile strength (N / mm 2< ) lower limitTensile strength (N / mm 2< ) upper limit2.0 - 3.07009503.0 - 4.06509004.0 - 5.05508305.0 - 20.0550700

[0083] Determining or measuring the diameter is preferably performed directly after the plastic elongation. Measuring the diameter may be effected in various ways.

[0084] In specific embodiments, the diameter is determined in an optical manner. This can be effected by directing a set of one or more light sources (for example laser bundles) in one or more directions at right angles to the wire and detecting the permeated light. Such an arrangement makes it possible to not only measure the diameter, but also the ovality and / or other parameters of the shape of the wire.

[0085] Suitable arrangements for measuring the diameter of the drawn or rolled wire are commercially available and can be obtained by a person skilled in the art.

[0086] In specific embodiments, the diameter may be determined in other ways, for example by means of the speed of the metal wire before and after elongation. It is possible to determine the lengthening of the wire, and thus also the corresponding reduction in diameter, from the change in speed. The speed of the metal wire may be determined via contact or non-contact measurements, as is known to the person skilled in the art. Suitable non-contact measuring techniques may comprise, for example, Doppler laser speed measurement. Optionally, several reference measurements of the wire diameter may be performed. As a result thereof, the diameter can be determined more precisely.

[0087] In specific embodiments, an additional monitoring of the wire diameter may be carried out by means of a wire diameter monitoring system.

[0088] The method described herein comprises, in a step (e), the (in-line) passing of the drawn or rolled metal wire across a return wheel device and / or through a wire straightener. The wire straightener is preferably composed of a first part consisting of a first set of wheels and a second part consisting of a second set of wheels, wherein each set in each case consists of at least three wheels.

[0089] If both a wire straightener and a return wheel device are provided, the wire straightener and return wheel device will have been placed in two different planes, so that the cast and helix of the drawn or rolled metal wire can be adjusted while the drawn or rolled metal wire is being passed through. Preferably, the diameter of the return wheel in the return wheel device is sufficiently large, while the wheels in the wire straightener are small compared to the diameter of the return wheel.

[0090] Inside the wire straightener, the wheels are arranged in such a way that upon contact of the advancing wire with a wheel, the wire is deflected from a linear course and in this case is depressed to a depression depth. In this case, the depression depth corresponds to the distance along which the wire is depressed, compared to a neutral state in which the wire is not deflected and would follow a linear course. Within one set of wheels, the wheels are typically distributed over a first row and a second row, so that when the wire is passed through the set, the wire successively comes into contact with a wheel from the one row and subsequently with a wheel from the other row. Upon contact with a wheel from the first row, the wire is bent in one direction, for example downwards, and upon contact with a wheel from the second row, the wire is bent in the opposite direction, for example upwards. Within one set of wheels, the wire may be depressed at every wheel to the same depression depth, or the depression depth may differ for each wheel, or the depression depth of some wheels may be the same and may be different for other wheels. If within one set of wheels, the wire is depressed at each wheel to the same depression depth, then this value is deemed to be the depression depth of the respective set of wheels of the wire straightener. If the wire straightener consists of a first part and a second part, the rotation axles of the wheels of the first part are preferably arranged horizontally, and the rotation axles of the wheels of the second part are preferably arranged vertically. For example, when passing the wire through the first set, it is deflected from the bottom to the top, and when passing the wire through the second set, it is deflected from the front to the back. When passing the wire through the first and second set of wheels, the depression depth of the first and second set may be the same or different. Typically, each set comprises several wheels, for example three, two of which are situated in one row and one of which is situated in the other row. In other examples, a set comprises five or seven wheels, with three or five wheels, respectively, being placed in a first row and two or four wheels, respectively, being placed in a second row. In yet other examples, a set comprises a large number of wheels, for example up to twenty wheels, distributed over two rows.

[0091] In specific embodiments, the wire straightener is used with a view to obtaining a desired cast and pitch of the wire, which are characteristic for the curvature and the degree of curling of the wire. Such parameters are important in order to be able to roll up a produced wire in a satisfactory manner, but even more important in order to be able to unroll it in a satisfactory manner. For example, on the one hand, the wire should be prevented from curling up too much like a spiral, but on the other hand, it also has to be possible to roll up the wire easily in accordance with a desired rolling-up diameter, and has to be easy to unroll. In such a case, the wire straightener is thus used to straighten the wire, i.e. to make it sufficiently straight and flat. With a view to straightening the wire, it typically suffices to adjust the wheels of the wire straightener in such a way that the wire is deflected or depressed only to a limited degree when being passed through the wire straightener. For example, there is hardly any depression, and the wire moves essentially closely past the wheels of the wire straightener. For example, when using the wire straightener as a straightener, the wheels are arranged in such a way that the depression depth at each of the wheels is at most 5 mm, for example at most 4 mm, for example at most 3 mm, for example at most 2 mm, for example at most 1 mm. In specific embodiments, the wire straightener for each of the wires to be produced is set as the straightener, thus always applying a limited depression depth. The latter may be the same for all wires, or may be different for different wires. In other embodiments, the wire straightener is only set as the straightener for certain wires to be produced, thus applying the limited depression depth.

[0092] In certain other embodiments, the wire is deflected or depressed to a greater degree when it is passed through a set of wheels of the wire straightener than is strictly necessary based on straightening the wire and obtaining the desired rolling and unrolling behaviour. For example, the wheels of a set are arranged in such a way that the depression depth at one or more of the wheels, or at each of the wheels, is at least 2 mm, for example at least 3 mm, for example at least 4 mm, for example at least 5 mm, for example at least 6 mm. For example, a depression depth is used which has at least the abovementioned value, and is at most 15 mm.

[0093] Bringing about a greater deflection or depression using at least one of the wheels of the wire straightener has the advantage that this produces a greater degree of deformation of the wire, so that, due to the Bauschinger effect, a softer wire is obtained than when no such (strong) deformation of the wire is applied. In this case, the expression a softer wire refers to a wire whose yield point Re or 0.2% yield stress, and the tensile strength Rm are sufficiently low, so that the resulting wire is sufficiently ductile and readily deformable. This is in contrast with a steel wire which has a greater hardness and strength, but lower ductility, and is less easily deformed.

[0094] In other words, in such embodiments, the wire straightener, or a set thereof, is used as a so-called softener, in order to achieve a desired - sufficiently low - wire strength. In such cases, the wire straightener or the set then typically has two functions, namely as a straightener for bringing about the desired winding and unwinding behaviour, and as a softener in order to achieve the desired yield point and tensile strength. The use of the wire straightener as a softener has the advantage that a sufficiently deformable wire is obtained, which is important for applications in which the metal wire will be used, for example, in woven nets or wire cable ducts. In addition, it makes it possible to use less expensive types of steel, for example produced from scrap, or less expensive scrap, without having to use softer, but more expensive types of material made from iron ore or more expensive scrap.

[0095] When using the wire straightener or a set of wheels inside the wire straightener as softener, various embodiments are possible with regard to the depression depth of the respective wheels. For example, a sufficiently large depression depth may be used for each of the wheels, for example the same large depression depth for each of the wheels, or a different (large) depression depth for each of the wheels, or a (large) depression depth which is the same on some wheels and is different on some wheels. In other examples, only a limited depression or none at all is used on one or more wheels, while a sufficiently large or even a very large depression depth is used on one or more other wheels.

[0096] In certain embodiments, the wire straightener for each of the wires to be produced is set as a softener, with a sufficiently large depression depth being applied on at least one of the wheels of the wire straightener for every wire. This setting of depression depth(s) may be the same for all wires, or may be different for different wires. In other embodiments, the wire straightener is only set as a softener for certain wires to be produced.

[0097] In certain embodiments, the wire straightener comprises two sets of wheels, and each of the sets is used as a softener. For example, the depression depth of each of the wheels in the first and second set is in each case at least 2 mm, for example at least 3 mm, for example at least 4 mm, for example at least 5 mm, for example at least 6 mm. For example, a depression depth is used which has at least the abovementioned value for each of the sets, and is at most 15 mm. In this case, the same or a different setting of depression depth(s) may be used for the first and the second set. In certain other embodiments, only one of the sets is used as a softener, in which a depression depth is used on at least one of the wheels which is greater than or equal to a threshold value, while the other set is used as a straightener, in which a depression depth is used on each of the wheels which is smaller than the threshold value. For example, the threshold value is 2 mm or 3 mm or 4 mm or 5 mm or 6 mm. For example, the first set of wheels of the wire straightener is set as a straightener, having a limited depression depth, and the second set of wheels is set as a softener, having a greater depression depth. In this case, the desired strength properties and deformability are brought about when a wire is passed through the first set, and the wire is subsequently finally straightened when it is passed through the second set before being rolled up.

[0098] In specific embodiments, the depression depth on each of the wheels of the wire straightener is at most 15 mm, for example at most 10 mm. In this way, the wire straightener can be used as a softener, but this also prevents an undulating pattern from becoming visible in the resulting wire due to excessive deformation. It is thus also prevented that the wire becomes excessively hot, as excessive heating may result in the soap film from coming off and soiled patches being created on the wire.

[0099] In certain embodiments, at least one of the wheels of the wire straightener is arranged so as to be movable, so that by displacing the one or more movable wheels, the depression depth of the metal wire can be varied. For example, each of the wheels is arranged so as to be movable, so that they are individually displaceable. For example, the wheels of one set are displaced together, so that in each case the same depression depth is achieved across all wheels of the set. Moving of the wheels typically takes place according to a linear translation, in a direction substantially at right angles to the feed-through direction or moving direction of the wire. In this case, wheels of opposite rows in a set are moved towards each other or away from each other. For example, in a set, the wheels from a top row are moved down and the wheels from the bottom row are moved up, so that the mutual distance between the bottom and top row decreases and a greater depression depth of the wire is obtained. The displacement of the wheels may be brought about in a mechanical way and manually, or may be actuated by means of an actuator in a way known to the person skilled in the art.

[0100] In specific embodiments, each set of wheels of the wire straightener is used as a straightener for certain metal wires, using a limited depression depth for each of the wheels, and one or more sets of wheels of the wire straightener are used as a softener for other metal wires, using a greater depression depth on at least one of the wheels of the set. For example, with a depression depth on all wheels smaller than a threshold value, the wire straightener or the set is set as a straightener, and with a depression depth on at least one of the wheels greater than a threshold value, the wire straightener or set is set as a softener. This threshold value is, for example, 2 mm or 3 mm or 4 mm or 5 mm.

[0101] In specific embodiments, the depression depth of the respective wheels of the wire straightener is set on the basis of one or more wire parameters. In this case, it is possible to set the same depression depth for each of the wheels, or different depression depths may be set for the various wheels. The wire parameters are for example characteristic of the initial wire at the start of the production process, and / or are characteristic of the desired wire at the end of the production process. Parameters characteristic of the initial wire are, for example, the type of steel or initial wire diameter. Parameters characteristic of the desired wire are, for example, strength parameters such as the desired tensile strength, desired yield point, desired hardness, or form parameters, such as the desired wire diameter, pitch, helix or cast. In such embodiments, the wire straightener is thus adjustable, with a set value for the wheels corresponding to the desired depression depth being determined for each wheel or for each set of wheels, by selecting a set value on the basis of wire parameters. Selection of the set value may be carried out on the basis of one of said parameters, for example the desired tensile strength, or on the basis of a combination of several of said parameters. Such a selection may be performed manually or automatically. After selection of the set value(s) for the respective wheels has taken place, each of the wheels is set to the selected depression depth. In this case, it is possible that, depending on the parameters, all wheels are set to a limited depression depth, so that the wire straightener is purely used as a straightener, or - with other applicable parameters - one or more or all wheels of the wire straightener are set to a great depression depth, so that the wire straightener, or at least a set thereof, is used as a softener.

[0102] The use of the wire straightener, and the adjustment thereof, as a straightener and / or as a softener, has the advantage that it is possible to produce the desired strength properties and the desired winding behaviour and unwinding behaviour in a simple mechanical way. Performing a large deformation with a wire straightener at the end of the production process carries with it a certain risk, because deformations in the wire might remain visible or the wire might be soiled due to excessive heating of the wire and the soap coming off. However, surprisingly, it has been found that by selecting the optimum depression depths, such a risk is limited and at the same time the desired strength and winding properties are produced.

[0103] In the context of the overall production process, it was found in particular that it becomes possible, through a unique combination of subprocesses, to provide a production process which, on the one hand, enables meeting the stringent quality standards for metal wires to be produced and, on the other hand, using simple, mechanical subprocesses. This avoids, for example, steps using pickling or annealing, which contribute to meeting quality standards, but render the production process expensive and / or polluting. It was found in particular that stripping can be performed mechanically by using brushes and / or rotating wheels, in combination with a wire straightener further downstream in the production line, used to straighten and / or soften the wire. In this way, stresses which are induced during mechanical stripping and / or during wire drawing and which cause material reinforcement and insufficient deformability, are neutralized again by means of the wire straightener, due to the Bauschinger effect, so that a sufficient degree of softness and deformability is achieved. The combination of simple mechanical processes which has been discovered thus makes it possible to push the wire properties in the direction of the desired properties in a unique way and to meet stringent quality standards - which may, in addition, differ depending on the application.

[0104] In specific embodiments, the wire straightener is cooled. Typically, the wire heats up during the production process, for example up to 50°C when it reaches the winding coil. In particular when the wire straightener is set as a softener, this heating up is even greater, for example an additional heating up of approximately 15°C, to 65°C during winding up. Excessive heating up of the wire may be disadvantageous, since as a result thereof there is a risk of the soap layer breaking off and breaking away, and leads to dirty wheels. The latter possibly results in dirt accumulating on the wire, which is unacceptable. In certain embodiments, cooling ducts are provided in the wheels of the wire straightener, wherein a cooling agent, for example cooling water, is passed through the cooling ducts. There is, for example, one cooling duct in every wheel, which extends along the rotation axle of the wheel. In this case, the cooling agent may flow, for example, from the front of a wheel to the rear, thereafter to the rear of a subsequent wheel, etc. In specific embodiments, the cooling of the wire straightener is brought about by placing a housing around the first and / or second set of wheels, and passing a cooling agent, for example cooling air, through the housing. A combination of cooling measures, wherein for example a first cooling agent is passed through cooling ducts in the wheels, and a second cooling agent is passed through a housing around the wire straightener, is also possible.

[0105] As a last step (f) in the method described herein, the drawn or rolled metal wire is wound up onto a coil. To this end, a winding device is preferably provided wherein a wire guide is positioned for the winding device in order thus to guide the metal wire during winding up. Preferably, the residual lubricant content of the applied lubricant after the winding up of the drawn or rolled metal wire is at most 3.0 g / m 2< . In certain cases, the residual lubricant content is limited even more, for example to 1.5 g / m 2< or to 0.5 g / m 2< .

[0106] In specific embodiments, the method described herein may comprise a passivating step. Such a passivating step will typically take place before or after step (e). Passivating leads to the spontaneous formation of a hard non-reactive surface film which slows down further corrosion, and may be achieved by submerging the wire in one or more passivating solutions, as known to the person skilled in the art. Passivating is usually performed after plastic elongation and optionally drawing and / or stress relief of the wire.

[0107] In a specific embodiment, the present invention also provides a metal wire manufactured using an embodiment of a method as described herein.EXAMPLES

[0108] Fig. 1 shows a diagrammatic representation of a specific embodiment of the method described herein for drawing or rolling a metal wire.

[0109] The method comprises, in a first step (1001), providing a rolled-up rod wire, and the continuous unwinding of the rod wire. The wire is conveyed through the various steps of the method at a speed of approximately 7 m / s (typically between 1m / s and 15m / s). In a first step (1002), the circumference of the wire is stripped. In a next step (1003), a lubricant is applied to the surface of the stripped rod wire. Subsequently, the rod wire is drawn (1004) by passing the rod wire over at least one wire drawing device which exerts a force on the rod wire. In this case, the wire is reduced by approximately 5% to 40%. Alternatively, the wire is rolled by drawing the wire through a rolling head. In a next step (1005), the drawn or rolled metal wire is passed through a wire straightener and / or return wheel device, wherein the cast and helix of the drawn or rolled metal wire may be adjusted. In a last step (1006), the metal wire is rolled up.

[0110] Fig. 2 diagrammatically shows the rod wire 5 which has been wound onto a rod wire bundle 6 and placed on two vertical towers 7. An end of the first rod wire bundle 6a is connected to an end of the second rod wire bundle 6b. Preferably, the ends are welded to each other 8 in order thus to be able to create a continuous process and to supply the rod wire 5 in an uninterrupted manner to the stripping device. The rod wire 5 preferably consists of a low-carbon steel, such as of the types of SAE 1004 to SAE 1020 metal. To ensure good galvanization, the silicium content present in the rod wire will either be at most 0.03% or will be at least 0,14%.

[0111] Fig. 3 shows a stripping device 10, wherein a first set of rotating wheels 11, 12, 13, 14, 15 is provided, so that the rod wire 5 can be guided along the rotating wheels 11-15 in an S-shaped course. The rotation axles of the rotating wheels 11-15 are positioned horizontally. The rotating wheels 11, 12 and 15 are arranged so as to be movable and can be raised and / or lowered by means of a controllable mechanism 16 in order thus to modify the course of the rod wire 5, but this is not imperative. The rotating wheels 13 and 14 are fitted on a movable disc 17, wherein the movable disc or background disc 17 may be rotated about its centre point. Rotating the movable disc 17 results in the course, for example the S-shaped course which is situated between the rotating wheel 12 and the rotating wheel 15, being changed. Changing the course means that the rod wire 5 will be bent in a different way, as a result of which the outer mill scale will crack and / or break off in a different way. In addition, due to the position of the various rotating wheels 11,12,13,14,15 with respect to each other, a first reduction of the diameter of the rod wire 5 can already be obtained.

[0112] Fig. 4 shows a second set of rotating wheels 21, 22, 23 of the stripping device 10 and thus forms a second part of the stripping device 10. (the entirety may also be arranged in one machine). The rod wire 5 coming from the rotating wheel 15 of the first set will then be bent further by means of the second set of rotating wheels 21-23 in order to break the mill scale further and to remove it. The rotation axles of the rotating wheels 21-23 are essentially arranged vertically, typically resulting in a different bend than is the case when bending about the first set of rotating wheels 11-15 which are essentially arranged horizontally. In an alternative arrangement, the rotating wheels may also be arranged at an angle of, for example, 45° and -45°, as a result of which the mill scale can be removed from the arrangement more easily.

[0113] Fig. 5 shows a helical brush 25 which is arranged in a swinging manner, so that it can perform a pulsating and vibrating movement. Such a helical brush 25 is a brush provided with a plurality of small metal wires, wherein the brush is configured in a helical shape through which the rod wire 5 will be passed. The helical brush 25 is arranged in a swinging manner, with the helical brush 25 making a reciprocating or pulsating movement. Preferably, the helical brush 25 will thus perform a vibrating movement. A linear motor or a pneumatic cylinder (not shown) which cause the movements of the helical brush 25 may be provided. Due to this vibrating and pulsating movement, the helical brush 25 will brush the surface of the rod wire 5 efficiently and is self-cleaning. The helical brush 25 may be arranged at any desired position along the course through the stripping device 10. Preferably, a first helical brush 25 is provided after the second set of rotating wheels 21-23 and a second helical brush 25 is provided before the first soap reservoir 40 (see Fig. 8). By using such helical brushes 25, the surface of the rod wire 5 will be cleaned in an optimum manner and any partly detached mill scale particles or other impurities will be removed before lubricant is applied to the surface of the rod wire 5.

[0114] Fig. 6 shows a rotor device 30 which forms part of the stripping device 10, in which cleaning pads 32, 34 may be provided. The rod wire 5 is inserted in the rotor device 30 on a first side, is then passed through the rotor device 30, after which the rod wire 5 will exit the rotor device 30 again on a second side, opposite the first side. The rotor device 30 may consist of one or more rotors which rotate about the rod wire. Cleaning pads are fitted in the rotor device 30, with the cleaning pads being arranged in such a way that the rod wire 5 is in contact with the cleaning pads. The cleaning pads are pushed against the rod wire 5 with a certain force in order to ensure satisfactory action. To prevent the rod wire 5 from following an undulating course as a result of the force exerted on of the cleaning pads, the rotor device 30 may be provided with one or more support means, along which the rod wire 5 will move. Using such support means at regular intervals within the rotor device 30 makes it possible to prevent the undulating movement of the rod wire 5 caused by the cleaning pads 32, 34 being pushed from being such that optimum cleaning by the cleaning pads 32, 34 is no longer possible.

[0115] Fig. 7A shows a first embodiment of the cleaning pads 32, Fig. 7B shows an alternative embodiment of the cleaning pads 34. The cleaning pad 32 as illustrated in Fig. 7A is a mainly cylindrical tube, in which a plurality of small metal wires are contained in a synthetic polymer along substantially their entire length. Preferably, the front of the cleaning pad 32, being the side which will be brought into contact with the moving rod wire 5, is provided with a groove 33. While it is being operated, the rod wire 5 will move in the groove 33 and, due to the shape of the groove, a larger surface of the rod wire 5 can be brought into contact with the small metal wires and polymer surface of the cleaning pad 32.

[0116] Fig.7B illustrates an alternative embodiment of a cleaning pad 34, in which the contact surface of the cleaning pad 34 which will be brought into contact with the advancing rod wire 5 is longer compared to the contact surface of the cleaning pad 32, as illustrated in Fig. 7A. The cleaning pad 34 is likewise provided with a groove 35, so that the rod wire 5 can again be cleaned in an optimum manner when the rod wire 5 is passed through the groove 35 of the cleaning pad 34. The use of an elongate shape, such as the cleaning pad 34, versus a round shape, such as the cleaning pad 32, ensures that less material is required for constructing the cleaning pad 34. The fact is that only the zone of the grooves 33, 35 will come into contact with the rod wire 5.

[0117] Normally, the zones above and below the grooves 33, 35 will not be brought into contact with the rod wire 5 and will consequently not contribute to cleaning of the rod wire 5, as a result of which the life of the cleaning pad is significantly increased.

[0118] Fig. 7B also shows a holder 36 for the cleaning pad 34. The holder 36 has a shape which is similar to the shape of the cleaning pad 34, so that the cleaning pad 34 can be introduced into the holder 36 and can be held there when the rod wire 5 runs in the groove 35. The holder 36 is provided with two supports 37 which are arranged around pivot axle 38. A bracket 39 to which the pivot axle 38 is attached, is mountable to the rotor device 30. Depending on the diameter of the rod wire 5, it may be necessary to position the cleaning pad 34 closer to or further away from the rod wire 5, and the holder 36 and the supports 37 may be repositioned by pivoting the supports 37 about the pivot axle 38.

[0119] During stripping, the rod wire 5 may heat up, due to bending of the metal wire 5 around the rotating wheels 11-15 and 21-23 and / or due to friction of the cleaning pads 32, 34 and / or the helical brushes 25.

[0120] Fig. 8 shows a first soap reservoir 40 provided with lubricant for applying the lubricant to the surface of the stripped rod wire 5 and a first drawing die holder 50 for drawing the rod wire 5. The lubricant provided in the first soap reservoir 40 is preferably a soap whose active component consists mainly of calcium stearate or a calcium / sodium stearate mixture. The rod wire 5 is first passed through the first soap reservoir 40, after which the rod wire is supplied to the inlet side of the drawing die holder 50. When the stripped rod wire 5 is passed through the inlet side of the drawing die holder 50, the diameter of the rod wire will decrease and ultimately the drawn metal wire 5' will have the diameter of the outlet side of the drawing die 54.

[0121] As has already been indicated, the temperature of the rod wire 5 will increase during the wire drawing. In order to lower this temperature, the drawing die holder 50 is cooled directly or indirectly. As a result thereof, the drawing die holder 50 is cooled internally.

[0122] Fig. 9 shows a second soap reservoir 60 and a second rotating capstan 70 for drawing the drawn metal wire 5' further. Before the drawn metal wire 5' undergoes an additional reduction as a result of the second reduction step, the drawn metal wire 5' will again be passed through a second soap reservoir 60. The lubricant provided in the second soap reservoir 60 is preferably a soap whose active component consists mainly of sodium stearate. The second capstan 70 is a cylinder around which the drawn metal wire 5' runs. The cylinder is arranged at an angle of inclination and the drawn metal wire 5' will be supplied to the cylinder at the bottom, run at least 1x around the cylinder and leave the cylinder surface again, for example, halfway along the cylinder. By running around this cylinder and simultaneously drawing on the drawn metal wire 5', the diameter of the drawn metal wire 5' will decrease further before it is passed through the second soap reservoir 60 and drawing die. It is possible to provide several soap reservoirs and rotating drums in order thus to achieve the desired diameter of the drawn metal wire 5'. In that case, the lubricant in the additional soap reservoirs is preferably a soap whose active component mainly consists of sodium stearate.

[0123] Fig. 10 shows an example of emulsion reservoir 80 for applying the emulsion to the circumference or surface of the drawn metal wire 5', before the drawn metal wire 5' undergoes its final reduction.

[0124] The emulsion reservoir 80 is provided with a tubular duct 82 through which the rod wire will be passed. A supply line 84 provides an emulsion to the tubular duct 82 in order thus to provide the tubular duct 82 with sufficient lubricating emulsion.

[0125] Consequently, the drawn metal wire 5' will be passed through the tubular duct 82 while the emulsion is being applied in order thus to provide the drawn rod wire 5' with the emulsion on all sides.

[0126] Fig. 11 shows an alternative for a reduction using a drawing die, namely a roller block: the wire is surrounded by at least 2 rollers. The inlet diameter of the incoming wire is greater than the passage opening which is formed by the opening between the rollers. As a result thereof, the wire is reduced, and a longer, thinner wire is produced. The rollers may or may not be cooled, by means of, for example, cooling ducts in the shafts of the rollers. Use may be made of one set of reducing rollers, or successive sets of reducing rollers. The passage opening of the rollers, defines the shape of the section of the wire. This may be, for example, round, but also triangular.

[0127] Fig. 12 shows a wire straightener 90,92 and a return wheel device 94 for straightening the drawn or rolled metal wire 5'. The wire straightener is composed of a first part 92 consisting of a first set of wheels and a second part 90 consisting of a second set of wheels, wherein each set in each case consists of at least three wheels, for example five or seven wheels. The rotation axles of the five or seven wheels of the first part 92 are, for example, arranged horizontally, whereas the rotation axles of the seven wheels of the second part 90 are arranged vertically. The wire straightener 90, 92 and return wheel device 94 are arranged in two different planes, so that the cast and helix of the metal wire 5' can be adjusted while the drawn or rolled metal wire 5' is being passed through. Preferably, the diameter of the return wheel in the return wheel device 94 is sufficiently large, whereas the wheels in the wire straightener 90, 92 are small in comparison to the diameter of the return wheel 94, this in combination with the tensile strength of the wire. As a result thereof, the internal stresses are redistributed and the cast and pitch can be adjusted.

[0128] Fig. 13 to 15 show an alternative embodiment of a wire straightener, in which the figures show a first set of wheels 98. The first set consists of seven wheels, arranged in two rows of four and three wheels, respectively. The wire straightener furthermore also comprises a second set consisting of seven wheels. Fig. 14 shows a detail, which makes it clear that the metal wire is deflected as a result of contact with the wheels and is depressed as far as a depression depth 102. In this case, the depression depth 102 corresponds to the distance of the point at which the wire is deflected the most, to a reference line 101, wherein the reference line corresponds to a neutral state in which the wire is not deflected and follows a linear course. Fig. 13 shows that the wire straightener 98 is adjustable, wherein the wheels of the set can be displaced along a direction 100, substantially at right angles to the linear supply course 99 of the wire. By displacing the wheels, the depression depth brought about by means of the wire straightener 98 can be changed. In this way, the wire straightener may be set as a straightener, with a limited depression depth of the wire, or as a softener, with a larger depression depth of the wire. In addition, Fig. 15 illustrates that the wheels of the wire straightener 98 are provided with cooling ducts 103. In this case, each wheel comprises a cooling duct which extends along its rotation axle. As is illustrated by means of the arrows 104, a cooling agent, for example water, is successively passed through the ducts of successive rollers in the same row.

[0129] By means of an arrangement comprising a wire straightener as shown in Fig. 13, a number of tests were performed in order to verify the effect of the depression depth on the obtained yield point and tensile strength. From these, it was inferred that, for an inexpensive type of steel, such as SAE-1008, and a regular initial wire diameter of 5.50 mm, a yield point and tensile strength are obtained which are 70 to 80 MPa lower if the first set of wheels is set as a softener, with a depression depth of 2 to 3 mm, compared to a situation in which the two sets of wheels are set as a straightener. By additionally setting the second set as a softener, with a depression depth of 2 to 3 mm being used in both sets of wheels, an additional reduction of approximately 20 MP in yield point and tensile strength was obtained compared to the situation in which only the first set was set as a softener.

[0130] Fig. 13 shows a wire guide 95 and the coil 96 for winding up of the final produced and drawn or rolled metal wire 5'. The wire guide 95 is positioned for the winding device 97 in order thus to guide the metal wire 5'while it is being wound up around the coil 96.

[0131] The separate components as illustrated in Figs. 2 to 13 may be placed in line as follows, resulting in a continuous process for manufacturing the drawn or rolled metal wire 5': the rolls of metal wire which are wound onto a rod wire bundle 6 and have been placed on vertical towers 7, as illustrated in Fig. 2; the first set of rotating wheels 11-15 of the stripping device 10, as illustrated in Fig. 3; the second set of rotating wheels 21-23 of the stripping device 10, as illustrated in Fig. 4; a first helical brush 25, as illustrated in Fig. 5; a rotor 30 of the stripping device as illustrated in Fig. 6, in which cleaning pads 34 as illustrated in Fig.7B have been arranged; a first soap reservoir 40 and a first drawing die holder 50, as illustrated in Fig. 8; a second soap reservoir 60 and a second drawing die holder 50 and a capstan 70, as illustrated in Fig. 9; a third soap reservoir 60 and a third drawing die holder 50 and a third capstan 70; an emulsion reservoir 80, as illustrated in Fig. 10 a return wheel device 94 and a wire straightener 90, 92, as illustrated in Fig. 12 a wire guide 95 and coil 96, as illustrated in Fig. 13.

[0132] As an alternative to a first soap reservoir with a drawing die holder and / or a second soap reservoir with a drawing die holder, roller blocks may be used.

Examples

examples

EXAMPLES

[0108]Fig. 1 shows a diagrammatic representation of a specific embodiment of the method described herein for drawing or rolling a metal wire.

[0109]The method comprises, in a first step (1001), providing a rolled-up rod wire, and the continuous unwinding of the rod wire. The wire is conveyed through the various steps of the method at a speed of approximately 7 m / s (typically between 1m / s and 15m / s). In a first step (1002), the circumference of the wire is stripped. In a next step (1003), a lubricant is applied to the surface of the stripped rod wire. Subsequently, the rod wire is drawn (1004) by passing the rod wire over at least one wire drawing device which exerts a force on the rod wire. In this case, the wire is reduced by approximately 5% to 40%. Alternatively, the wire is rolled by drawing the wire through a rolling head. In a next step (1005), the drawn or rolled metal wire is passed through a wire straightener and / or return wheel device, wherein the cast and helix of ...

first embodiment

[0115]Fig. 7A shows the cleaning pads 32, Fig. 7B shows an alternative embodiment of the cleaning pads 34. The cleaning pad 32 as illustrated in Fig. 7A is a mainly cylindrical tube, in which a plurality of small metal wires are contained in a synthetic polymer along substantially their entire length. Preferably, the front of the cleaning pad 32, being the side which will be brought into contact with the moving rod wire 5, is provided with a groove 33. While it is being operated, the rod wire 5 will move in the groove 33 and, due to the shape of the groove, a larger surface of the rod wire 5 can be brought into contact with the small metal wires and polymer surface of the cleaning pad 32.

[0116]Fig.7B illustrates an alternative embodiment of a cleaning pad 34, in which the contact surface of the cleaning pad 34 which will be brought into contact with the advancing rod wire 5 is longer compared to the contact surface of the cleaning pad 32, as illustrated in Fig. 7A. The cleaning pad ...

FIELD OF THE INVENTION

[0001] The present invention relates to a method for drawing or rolling metal wires. The drawn or rolled wires are used, inter alia, in the manufacture of nails, both individual nails and interconnected nails, and woven or welded wire structures, (pig) slats or architectural slats or other wire applications.BACKGROUND OF THE INVENTION

[0002] Metal wire is an important raw material in the industrial sector and the building sector. However, in order to be usable, the wires have to meet certain properties. Thus, the wires not only have to be sufficiently deformable and achieve a sufficiently high tensile stress, but for certain applications, the surface has to be sufficiently pure.

[0003] In order to obtain metal wires having these desired properties, the initial selection of the metal wire with a certain carbon content is important and the wires typically have to undergo different processing steps as part of the production process, such as cleaning, rolling or wire drawing and optionally subsequent elongation and straightening. Sometimes, it is also important to determine the equivalent carbon content, to ensure that the wire is readily weldable.

[0004] In the production process of metal wires, various means and ways are already known for cleaning or stripping the metal wire. Mechanical cleaning is highly effective and is often preferred to chemical cleaning processes because chemical cleaning processes often require the use of highly toxic agents in order to clean the metal wire. In addition, chemical cleaning is generally also more expensive. Systems for effecting a mechanical cleaning of the metal wire are also already known. These systems generally use for example steel wool, sandpaper or other abrasive means which are pushed against the metal wire at a predetermined pressure. When the metal wire moves along these abrasive parts, the oxide particles or other impurities which cover the metal wire are removed and the metal wire is cleaned effectively.

[0005] An alternative way of removing the oxide particles or other impurities covering the metal wire is the use of bending rollers. In this case, the metal wire is conducted along the bending rollers, resulting in the metal wire being bent in various locations. The bending procedure will lead to cracks in the mill scale which is composed of the oxide particles and / or other impurities, following which this broken mill scale will fall off the metal wire.

[0006] Drawing or rolling metal wire is a shaping technique in which a metal wire is elongated. Typically, there are two types of elongation. With elastic elongation, the metal wire is subjected to loads within its limit of elasticity. The elongation is cancelled when the load is removed. The value of the elastic elongation depends on the metal wire and the tensile strength, but is approximately 0.20% under normal conditions. Plastic elongation is permanent and occurs when the load exceeds the limit of elasticity. Plastic elongation of metal wire is carried out by means of generally known techniques and, for example, by guiding the metal wire across various rotating axles. It may also be achieved by drawing the wire through a drawing die and lastly it may also be achieved by means of a rolling head. In this case, the wire is drawn through a set of moulding rollers, resulting in the section of the wire changing and reducing.

[0007] The wire may have a round section or any other desired section, such as for example a triangular section. In recent years, many improvements have been made with regard to the methods and apparatuses which are used for the individual processing steps within the production process of metal wire. However, there is still a significant amount of room for improvement, in particular with regard to producing premium metal wires where the cleaning of the outer layer of the metal wire, the correct reduction of the wire diameter, and the accurate realisation of the desired strength properties form part of an efficient and high-quality production process. In particular, it is a challenge to be able meet stringent quality standards concerning wire diameter, strength and shape of the resulting wire, while simultaneously being able to use a simple production process and inexpensive grades of steel.

[0008] In view of the above, there remains a need in the field for improvements with regard to the production process for producing metal wires.SUMMARY OF THE INVENTION

[0009] The present invention generally relates to a method for manufacturing a drawn or a rolled metal wire. The method makes it possible to effectively clean or strip the metal wire and subsequently to draw or roll the wire, optionally followed by further adjustments, and finally to wind it up again.

[0010] More particularly, the present invention provides a method for manufacturing a drawn or rolled metal wire, comprising: (a) arranging a rod wire having a diameter of between 4.0 mm and 22.0 mm, the rod wire being provided on a roll with a cast of between 600 mm and 5,000 mm; (b) stripping the rod wire by means of a stripping device, the stripping device comprising: a first set of at least two rotating wheels, wherein the rotating wheels are arranged in such a way that the rod wire follows an S-shaped course, and at least one rotor provided with at least one cleaning pad, wherein the rotor is configured to rotate about the rod wire, and wherein the at least one cleaning pad is in contact with the rod wire in order thus to brush across the outer layer of the rod wire; (c) applying a lubricant onto the surface of the stripped rod wire and wherein the lubricant is applied to the surface of the rod wire before said rod wire is drawn or rolled, so that the wire drawing or rolling is performed on a lubricated rod wire; (d1) wire drawing said rod wire by means of at least one wire drawing device comprising the combination of a drawing die holder and a capstan, and / or (d2) wire rolling said rod wire by means of at least one rolling head, wherein a lubricant may be applied for each rolling head; (e) passing the drawn or rolled metal wire through a return wheel and / or a wire straightener, wherein the wire straightener consists of at least three wheels; and (f) preferably winding up the drawn or rolled metal wire onto a coil by means of a winding device, wherein a wire guide is positioned in front of the winding device.

[0011] In step (d1), the wire drawing is performed using one or more wire drawing devices, wherein a wire drawing device comprises a combination of a drawing die holder and a capstan. In this case, lubricant is preferably applied for at least one combination of drawing die holder and capstan. When several combinations of wire drawing die holder and capstan are provided, preferably no lubricant is applied for the last combination of wire drawing die holder and capstan in order to prevent an excessive amount of soap from being provided on the drawn or rolled metal wire. In order to ensure that the residual soap on the drawn or rolled metal wire is as low as possible, preferably no lubricant is applied for the last two combinations of wire drawing die holder and capstan.

[0012] The final wire diameter of the drawn or rolled metal wire is between 2.0 mm and 20.5 mm, wherein the metal wire is provided on a roll with a cast of between 400 mm and 10,000 mm and a helix of at most 200 mm.

[0013] Preferably, the rod wire is wound onto a rod wire bundle, in which case the rod wire is fitted via at least two vertical or horizontal towers, and wherein a rod wire bundle is in each case fitted to a vertical or horizontal tower, so that the end of a first rod wire bundle may be coupled to the start of a second rod wire bundle, preferably via welding the ends together, in order thus to achieve uninterrupted fitting of rod wire.

[0014] Preferably, the rod wire consists of a low-carbon steel, preferably from the types of metal SAE 1004 to SAE 1020, and wherein the silicium content in the rod wire contains at most 0.03% Si or wherein the Si content is at least 0.14%. Providing a rod wire having these silicium contents will ensure that the metal wire can be galvanized in an optimum manner.

[0015] Preferably, the diameter of the drawn or rolled metal wire is between 2.0 and 20.0 mm. More preferably, the diameter of the drawn or rolled metal wire is between 2.07 mm and 2.17 mm, preferably between 2.40 mm and 2.55 mm, between 2.70 mm and 2.90 mm and between 2.90 and 3.20 mm, between 3.25 mm and 3.50 mm, between 3.60 and 3.75 mm, between 3.90 mm and 4.15 mm, between 4.40 mm and 4.90 mm, or between 4.90 mm and 5.90 mm, or between 5.90 and 6.10 mm, or between 6.10 and 7.20 mm, or between 7.20 and 8.20 mm, or between 8.20 and 10.20 mm, or between 10.20 and 12.30 mm, or between 12.30 and 14.50 mm, or between 14.50 and 20.50 mm. The diameter has a tolerance of + / - 0.020 mm, or + / - 0.030 mm, or + / - 0.040 mm, or + / - 0.060, or + / - 0.10 mm, or + / - 0.50 mm.

[0016] Depending on the diameter, the rolled or drawn metal wire preferably has a tensile strength in accordance with the following table: Diameter (mm)Tensile strength (N / mm 2< ) lower limitTensile strength (N / mm 2< ) upper limit2.0 - 3.07009503.0 - 4.06509004.0 - 5.05508305.0 - 20.0550700

[0017] Preferably, the rod wire will heat up during the step of stripping the rod wire.

[0018] Preferably, the at least two rotating wheels are arranged so as to be movable, and wherein the positions of the rotating wheels are adjustable with respect to each other in order thus to be able to modify the S-shaped course.

[0019] Preferably, the rotating wheels are mounted on a movable background disc, wherein the background disc is configured in such a way that the position of the background disc will determine the S-shaped course. Depending on the position of the rotating wheels relative to each other, the rotating wheels can bring about a first reduction of the rod wire.

[0020] Preferably, the stripping device furthermore consists of a second set of rotating wheels, the second set of rotating wheels consists of at least three wheels, wherein the rotation axles of the wheels of the first set are essentially arranged horizontally and the rotation axles of the three wheels of the second set are essentially arranged vertically.

[0021] Preferably, the stripping device furthermore consists of at least one helical brush, wherein the at least one helical brush is preferably arranged after the at least one rotor and / or before the application of the lubricant on the surface of the stripped rod wire. Preferably, the at least one helical brush is arranged in a swinging manner and / or the at least one helical brush is capable of performing a pulsating and / or vibrating movement. Preferably, a linear motor or a pneumatic cylinder is provided which brings about the pulsating and / or vibrating movement of the at least one helical brush.

[0022] Preferably, the stripping device consists of at least two rotors, and wherein the rotors rotate in the same direction or wherein the rotors rotate in an opposite direction.

[0023] Preferably, the stripping device furthermore consists of at least one support means to support the rod wire at the location of the at least one rotor in order thus to compensate for the pushing forces of the at least one cleaning pad on the rod wire. When the at least one cleaning pad is being pushed against the rod wire in order to clean the metal wire efficiently, it is possible that the rod wire may be pushed sideways if the pushing force of the cleaning pad is excessively high. By using a support means which will form a wall as it were against which the rod wire will be displaced, the rod wire will only experience a limited displacement due to the pushing force of the cleaning pad, thus resulting in an improved cleaning action of the at least one cleaning pad. Preferably, the at least one cleaning pad is provided with a plurality of metal wires which are contained in a synthetic polymer along substantially the entire length. Furthermore, the at least one cleaning pad is preferably tubular, oval, beam-shaped or cube-shaped. Preferably, the at least one cleaning pad is provided with an indentation, preferably along the entire length of the at least one cleaning pad, wherein the rod wire is passed through the indentation, and wherein the at least one cleaning pad cleans the rod wire and supports it during cleaning. By making use of an indentation, it will be possible to pass the rod wire as it were between the metal wires which are contained in the synthetic polymer, as a result of which virtually the entire circumference of the rod wire will be cleaned by the cleaning pad.

[0024] Preferably, the lubricant provided in step (c) is an emulsion, wherein the emulsion is introduced in a tubular duct, and wherein the rod wire is passed through the tubular duct during application of the emulsion in order thus to provide the rod wire with emulsion on all sides. Preferably, the lubricant is a soap, with the active component of the soap mainly containing calcium stearate or sodium stearate, or containing a combination of calcium stearate and sodium stearate.

[0025] In addition, preferably no soap is used in the last drawing die.

[0026] Preferably, the step of wire drawing or rolling of the rod wire will produce a reduction in the diameter of the metal wire of 5.0% to 40.0% when the rod wire moves through a first wire drawing device. During optional subsequent steps, the rod wire may be reduced further, again with a reduction of 5.0% to 40.0% per step. In an alternative embodiment, an equal reduction in the diameter of the rod wire will in each case be obtained every time the rod wire moves through successive wire drawing devices during the drawing step of the rod wire. In a likewise alternative embodiment, a continuously decreasing reduction in terms of percentage of the diameter of the metal wire will in each case be obtained during the drawing step of the rod wire. In a likewise alternative embodiment, an adjusted decrease in the reduction in terms of percentage of the diameter of the rod wire will in each case be obtained during the drawing step of the rod wire, in order to ensure that the power consumption should be the same at every step.

[0027] Preferably, at least one wire drawing device consists of a rotating drawing die holder and a wire drawing die. The wire drawing die may be cooled either directly or indirectly. Preferably, the wire drawing die is cooled indirectly, with the cooling being an internal cooling in the wire drawing die, so that the rod wire is cooled by the wire drawing die while it moves. In this way, it will be possible to reduce the diameter of the rod wire, while the drawing process is preferably carried out at a temperature below the recrystallization temperature of the metal. Cold-drawing typically results in an increase in the tensile strength of the metal wire. Preferably, the at least one wire drawing device is provided with a pressure set, so that the pressure set can increase the pressure on the soap, in order thus to support the passage of the rod wire and lubricant through the wire drawing die.

[0028] Preferably, the lubricant used between every wire drawing device is the same lubricant.

[0029] In an alternative embodiment, the lubricant used between every wire drawing device is different.

[0030] Preferably, the lubricant used and applied before the first wire drawing device is a soap substantially consisting of calcium stearate, and the lubricant used between every wire drawing device is a soap substantially consisting of sodium stearate.

[0031] Preferably, the lubricant used for the last wire drawing device is an emulsion soap; or preferably no soap is used in order thus to obtain a purer surface.

[0032] Preferably, the lubricant used between every combination of wire drawing die holder and capstan is lubricant.

[0033] Preferably, the lubricant used between every combination of wire drawing die holder and capstan is different, and preferably the lubricant used and applied before the first wire drawing device is a soap substantially consisting of calcium stearate, for every intermediate wire drum (70), the lubricant used is a soap substantially consisting of sodium stearate, and for the last wire drawing device the lubricant used is an emulsion soap.

[0034] Preferably, the wire in the last drawing die step is not provided with soap.

[0035] Preferably, the wire straightener comprises at least 3 wheels. Preferably, the wire straightener comprises at most 20 wheels.

[0036] Preferably, the wire straightener consists of a first part provided with at least three wheels and a second part provided with at least three wheels. The rotation axles of the three wheels of the first part are arranged horizontally, and the rotation axles of the three wheels of the second part are arranged vertically.

[0037] Preferably, the method comprises passing the drawn or rolled metal wire through a wire straightener, wherein the wire is depressed up to a depression depth by the respective wheels of the wire straightener. For example, the wire straightener comprises one or more sets of wheels. For example, in one or more sets of wheels of the wire straightener, the depression depth of each of the wheels is at most 5 mm, for example at most 4 mm, for example at most 3 mm, for example at most 2 mm, for example at most 1 mm, so that the respective set is set as a straightener. For example, in one or more sets of wheels, the depression depth of at least one of the wheels is at least 2 mm, for example at least 3 mm, for example at least 4 mm, for example at least 5 mm, for example at least 6 mm, so that the respective set is set as a softener. For example, the depression depth of each of the wheels of the wire straightener is at most 15 mm, for example at most 10 mm.

[0038] Preferably, at least one of the wheels of the wire straightener is arranged so as to be movable, so that the depression depth of the metal wire can be varied by displacing the one or more movable wheels.

[0039] Preferably, the depression depth of the movable wheels of the wire straightener is adjusted on the basis of one or more wire parameters. For example, the one or more wire parameters are characteristic of the initial wire at the start of the production process, and / or are characteristic of the desired wire at the end of the production process. For example, the one or more wire parameters are characteristic of the desired strength or softness of the metal wire.

[0040] Preferably, the wire straightener is cooled. For example, a cooling duct is arranged in each wheel of the wire straightener, extending along the rotation axle of the wheel and adapted for passing through a cooling agent, for example water. For example, the wire straightener is surrounded by a housing, and a cooling agent, for example air, is passed through the housing.

[0041] Preferably, the residual lubricant content of the applied lubricant after winding up the drawn or rolled metal wire is at most 3.0 g / m 2< wire surface, for example at most 1.5 g / m 2< , for example at most 0.5 g / m 2< .

[0042] Preferably, the wire section of the metal wire has a round or triangular shape. Preferably, the metal wire has a round shape. Preferably, the metal wire has a triangular shape, wherein, more preferably, at least one of the 3 sides has a profiled surface.

[0043] In an additional embodiment according to the invention, a metal wire is manufactured using one of the above preferred methods.

[0044] These and further aspects and embodiments of the invention are explained in more detail in the following chapters and in the claims and are also illustrated by means of non-limiting examples.BRIEF DESCRIPTION OF THE FIGURES

[0045] Fig. 1 diagrammatically illustrates a specific embodiment of the method described herein. Fig. 2 diagrammatically shows the metal wire which is wound on a rod wire bundle and placed on vertical towers. Fig. 3 diagrammatically shows a stripping device, wherein a first set of rotating wheels is provided, so that the metal wire can be guided along the rotating wheels in an S-shaped course. Fig. 4 diagrammatically shows a second set of rotating wheels of the stripping device. Fig. 5 shows a helical brush which is arranged in a swinging way, so that it can make a pulsating and vibrating movement. Fig. 6 shows a rotor of the stripping device, in which cleaning pads are provided. Fig. 7A shows a first embodiment of the cleaning pads, Fig. 7B shows an alternative embodiment of the cleaning pads. Fig. 8 shows a first soap box provided with lubricant for applying a lubricant to the surface of the stripped metal wire and a first drawing die unit for drawing the metal wire. Fig. 9 shows a second soap reservoir and a drawing die unit, followed by a wire drum for drawing the metal wire onwards. Fig. 10 shows an emulsion reservoir for applying the emulsion on the circumference of the metal wire, before the metal wire undergoes its final elongation. Fig. 11 shows, as an alternative of the wire drawing, a rolling head. Fig. 12 shows a wire straightener and a return wheel device for straightening the drawn or rolled metal wire. Fig. 13 shows a set of wheels of a wire straightener. Fig. 14 shows a detail of the set from Fig. 13. Fig. 15 shows the set from Fig.13 and illustrates how the wire straightener has been provided with cooling ducts. Fig. 16 shows a wire guide and the coil for winding up the drawn metal wire. DETAILED DESCRIPTION OF THE INVENTION

[0046] Before describing the present method and the devices which are used in the invention, it should be understood that this invention is not limited to specific described methods, components or devices, since such methods, components and devices may obviously vary. It should also be understood that the terminology used herein is not intended to limit, since the operating area of the present invention will only be limited by the attached claims.

[0047] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is generally understood by a person skilled in the art to which this invention appertains. Although in practice or when testing the present invention, it is possible to use all methods and materials which are similar to or equivalent to those described herein, the methods and the materials which are preferred will now be described.

[0048] As used herein, the singular forms "a", "an" and "the" include both the singular and the plural of the term referred to unless the context clearly indicates otherwise.

[0049] The terms "comprising" and "comprises" as used herein are synonymous with "including", "containing" or "contains", and are inclusive or open and do not exclude any additional, unmentioned parts, elements or method steps.

[0050] The terms "comprising" and "comprises" also include the term "consisting of".

[0051] The definition of numeric ranges by means of end points comprises all numbers and fractions which fall within the respective ranges, as well as said end points.

[0052] The term "approximately" as used herein when referring to a measurable value, such as a parameter, an amount, a time period and the like, shall comprise variations of + / -10% or less, preferably + / - 5% or less, more preferably + / - 1% or less, and still more preferably + / - 0.1% or less of the specified value, in so far as such variations apply to the disclosed invention. It should be understood that the value to which the definition "approximately" refers is itself also specific and is preferably disclosed.

[0053] All documents which are cited in the present specification are hereby incorporated in their entirety.

[0054] Unless defined otherwise, all terms used in the disclosure of the invention, including technical and scientific terms, have the meaning as is generally understood by a person skilled in the art to which this invention appertains. As a further aid, definitions of the terms which are used in the description are included so as to better be able to appreciate the principles of the present invention.

[0055] In general, the present invention provides a method for manufacturing a drawn or rolled metal wire. In this case, the method will adjust, and preferably reduce, the diameter of a metal wire after the metal wire has been cleaned or stripped. After the drawn or rolled metal wire has been straightened, the metal wire will furthermore preferably be wound onto a coil, so that the drawn or rolled metal wire can be handled easily.

[0056] Wire drawing is a process in which the diameter of a thick metal wire is reduced by drawing it through one or more drawing dies. The drawing dies have a wire drawing opening which is smaller than the diameter of the metal wire, thus reducing the diameter of the metal wire by means of wire drawing.

[0057] Rolling is a shaping technique in which a metal wire is deformed by two or more rollers. Rolling a metal wire may be used to change the cross section of the wire and / or to provide a profile on the wire surface or to give the wire a special shape.

[0058] Plastic elongation is a shaping technique in which a metal wire is elongated permanently by subjecting it to a load in excess of its limit of elasticity.

[0059] More particularly, the present invention provides a method for manufacturing a drawn or rolled metal wire, comprising: (a) arranging a rod wire having a diameter of between 4.0 mm and 22.0 mm, preferably wherein the rod wire is provided on a roll with a cast of between 600 mm and 5,000 mm; (b) stripping the rod wire by means of a stripping device, the stripping device comprising: a first set of at least two rotating wheels, wherein the rotating wheels are arranged in such a way that the rod wire follows an S-shaped course, and at least one rotor provided with at least one cleaning pad, wherein the rotor is configured to rotate about the rod wire, and wherein the at least one cleaning pad is in contact with the rod wire in order thus to brush across the outer layer of the rod wire; (c) applying a lubricant onto the surface of the stripped rod wire and wherein the lubricant is applied to the surface of the rod wire before said rod wire is drawn or rolled, so that the wire drawing or rolling is performed on a lubricated rod wire; (d1) wire drawing said rod wire by means of at least one wire drawing device comprising the combination of a drawing die holder and a capstan, and / or (d2) wire rolling said rod wire by means of at least one rolling head, wherein a lubricant may be applied for each rolling head; (e) passing the drawn or rolled metal wire through a return wheel and / or a wire straightener, wherein the wire straightener consists of at least three wheels; and (f) preferably winding up the drawn or rolled metal wire onto a coil by means of a winding device, wherein a wire guide is positioned in front of the winding device.

[0060] This method will be explained in more detail below.

[0061] The method described herein is particularly suitable for drawing or rolling a metal wire in a continuous manner. In this case, the metal wire is conveyed along a predetermined route in a continuous manner, preferably at a speed in the range from approximately 10 m / min to approximately 1200 m / min, more preferably at a speed in a range from approximately 50 m / min to approximately 800 m / min, and most preferably at a speed in a range from approximately 400 m / min to approximately 700 m / min. The conveying speed of the metal wire may be, for example, approximately 100 m / min, approximately 125 m / min, approximately 150 m / min, approximately 175 m / min, approximately 200 m / min, approximately 250 m / min, approximately 300 m / min, approximately 350 m / min, approximately 400 m / min, approximately 450 m / min, approximately 500 m / min, approximately 550 m / min, approximately 600m / min, approximately 650 m / min, or approximately 700 m / min. Since the diameter of the metal wire is being reduced in the present method, there is a difference between the speed of the metal wire for the drawing process or rolling process and the speed of the metal wire after the drawing process or rolling process. In this case, the difference in speed corresponds to the degree of lengthening of the wire. Thus, an incoming speed of 60 m / min with a lengthening of the wire of between 5% and 20% will result in a respective outgoing speed of 63 m / min and 75 m / min, an incoming speed of 120 m / min with a lengthening of the wire of between 5% and 20% will result in a respective outgoing speed of 126 m / min and 150 m / min. An incoming speed of 600 m / min and a lengthening of the metal wire of between 5% and 20% will result in a respective outgoing speed of 630 m / min and 750 m / min.

[0062] In a continuous process, the conveying speed of the metal wire remains virtually constant during each step of the process. The person skilled in the art will understand that due to the lengthening of the wire, the speed at which the metal wire is being conveyed expressed in weight unit per unit time typically remains constant, whereas the speed expressed in length unit per unit time may vary between the various steps of the process.

[0063] As used herein, the term "in-line" is understood to mean that the metal wire moves through the various steps of the method in a continuous manner. In other words, the various steps are performed simultaneously or successively without a noticeable delay. An "in-line" step of the method implies that the step is a part of the continuous method.

[0064] In a first step (a) of the method according to the present invention, a rod wire is provided. The rod wire may be provided on a roll or rod wire bundle. In certain embodiments, step (a) thus comprises the unwinding of a rod wire from a rod wire bundle, in which case the supply of the rod wire takes place via at least two vertical or horizontal towers, and in which case a rod wire bundle is placed on a vertical or horizontal tower in each case, so that the end of a first rod wire bundle can be coupled to the start of a second rod wire bundle, preferably by welding the ends to each other in order thus to produce an uninterrupted supply of rod wire.

[0065] Preferably, the rod wire consists of a low-carbon steel, preferably from the types of metal SAE 1004 to SAE 1020, and wherein the silicium content in the rod wire contains at most 0.03% Si or wherein the Si content is at least 0.14%. Providing a rod wire having these silicium contents will ensure that the metal wire can be galvanized in an optimum manner.

[0066] The rod wire provided in step (a) is, for example, a hot-rolled rod wire, preferably a metal wire consisting of a low-carbon steel, such as the types of metal SAE 1004 to SAE1020, preferably SAE 1006 to SAE 1010, wherein the silicium content in the metal wire is at most 0.03% or is at least 0.14%.

[0067] Preferably, the rod wire which is provided in step (a) is a smooth rod wire.

[0068] The rod wire may have any cross section, such as a round, square, rectangular, oval or semi-oval cross section. The rod wire according to the present invention may be chosen within a wide range of diameters which is between 4.0 mm and 22.0 mm, preferably between 4.0 mm and 16.0 mm and more preferably between 4.0 mm and 6.0 mm.

[0069] For wires having a noncircular cross section and / or a profiled surface, the term "diameter" as used herein denotes an equivalent diameter, more particularly on the basis of the wire weight of a theoretical smooth wire.

[0070] The metal wire is made from one or more metal or metal alloys, in a preferred embodiment, the wire is a steel or iron wire. Steel wires may be made from steel, preferably having a low-carbon content.

[0071] The method described herein comprises, in a step (b), the (in-line) stripping of the rod wire obtained in step (a), as described above. The stripping or cleaning of the rod wire is carried out by means of a stripping device. The stripping of the rod wire may be performed by means of various substeps in order thus to obtain a surface which is cleaned or stripped in as optimal a manner as possible. The stripping is preferably performed before the wire drawing or the rolling of the rod wire. The stripping entails the removal of any mill scale from the rod wire. Mill scale is a type of oxidation which is created during the production of new hot-rolled steel. The oxidation layer usually has a thickness of between 2 to 500 micrometres, depending on the rolling conditions of the steel. The presence of mill scale on the rod wire is usually undesirable because it can adversely affect the processing of the wires. Thus, the presence of mill scale may render welding of the wires more difficult, and mill scale breaking loose during the wire drawing process may cause damage to the equipment used in the process. Removal of the mill scale and any impurities on the surface of the rod wire may be effected in a mechanical or chemical way. Mechanical means to remove the mill scale may comprise, but are not limited to deforming, brushing, and / or abrasive blasting (such as sandblasting) of the rod wire. In a preferred embodiment, the mill scale is removed by (reversible) deformation of the wire. This is known to the person skilled in the art and based on the principle that the rod wire is typically flexible, whereas the mill scale is brittle. A sufficient degree of deformation (for example bending, torsion, and / or elongation) of the rod wire thus results in the mill scale breaking, as a result of which it will fall from the rod wire. This may be done in a continuous way, for example by bending the rod wire over a coil or rotating wheel. Stripping the rod wire according to the present invention is preferably effected by means of a first set of at least two rotating wheels or coils, wherein the rotating wheels are arranged in such a way that the rod wire follows an S-shaped course. Due to the fact that the rod wire is conducted over the rotating wheels via an S-shaped course, the rod wire will be bent in various locations of the S-shaped course. Due to these bends, the mill scale will have cracks, the mill scale will break and the mill scale will, at least partly, fall off the wire. Preferably, the at least two rotating wheels or coils are arranged so as to be movable, with the position of the rotating wheels or coils with respect to each other being adjustable. If the position of the rotating wheels or coils has been adapted, the S-shaped course will follow a different trajectory, resulting in the rod wire being bent in a different way. Preferably, the rotating wheels are mounted on a movable background disc, and the background disc is configured in such a way that the position of the background disc will determine the S-shaped course. Preferably, the mutual positions of the rotating wheels of the first set of the stripping device are continuously adjustable, as a result of which the S-shaped course will have a continuously changing trajectory and the curvature of the rod wire will always change slightly. As a result thereof, the mill scale will be broken up in a more effective manner and the amount of mill scale which is removed by the first set of rotating wheels of the stripping device will increase. During the step of stripping the rod wire, and mainly by the bending operation and the movement of the rod wire about the rotating wheels or coils, the rod wire will warm up. In addition, it is possible that, due to the position of the rotating wheels or coils with respect to each other, a first reduction of the diameter of the rod wire will be achieved.

[0072] In addition, it is possible that the stripping device also consists of a second set of rotating wheels, wherein the second set of rotating wheels consists of at least three rotating wheels or coils (or again consists of such a disc with 2 rotation axles). The rotation axles of the wheels of the first set are essentially arranged horizontally, and the rotation axles of the wheels of the second set are essentially arranged vertically. Due to the fact that the rotation axles of the wheels of the second set differ from the rotation axles of the first set, the bending to which the rod wire is subjected will change and will promote breaking of the mill scale. Another arrangement of the rotation axles of both the first and the second set is also possible.

[0073] In addition, the step (b) described herein provides at least one rotor provided with at least one cleaning pad. The rotor is configured to rotate about the rod wire. In this case, the at least one cleaning pad will be brought into contact with the rod wire in order thus to brush across the outer layer of the rod wire. Preferably, several cleaning pads are provided, with each cleaning pad being provided with a plurality of metal wires, for example small steel wires which are contained in a synthetic polymer, such as rubber, along substantially their entire length. By providing a synthetic polymer, such as rubber, into which the small steel wires are cast, the rod wire will take more time in finding a way through the small steel wires and will be cleaned more thoroughly in the process. Preferably, the at least one cleaning pad is tubular, oval, beam-shaped or cube-shaped. When use is made of a cleaning pad which has an elongate shape, the rod wire will be in contact with the cleaning pad for a longer period of time. As a result thereof, the rod wire will not develop a fold as quickly, as a result of which it is easier to clean and the efficiency of the other cleaning pads is maintained. In addition, it is possible to provide the at least one cleaning pad with an indentation, preferably along the entire length of the cleaning pad, with the rod wire being passed through the indentation. In this way, the pressure force which is applied to the rod wire by the cleaning pad will be distributed more evenly and the rod wire to be cleaned will be more effectively encapsulated and supported during cleaning.

[0074] If desired, it is possible to provide the stripping device with at least two rotors. The rotors may optionally rotate in the same direction or in an opposite direction.

[0075] In specific embodiments, the stripping device may furthermore consist of at least one helical brush and with the at least one helical brush preferably being arranged after the at least one rotor and / or before the application of the lubricant to the surface of the stripped metal wire. It is likewise possible to arranged a helical brush before the at least one rotor and after the first and second set of at least two rotating wheels. The helical brushes are preferably arranged in a swinging way. Preferably, they may also make a pulsating and / or vibrating movement, optionally in combination with the swinging arrangement. Preferably, a linear motor or a pneumatic cylinder causes the pulsating and / or vibrating movement of the at least one helical brush.

[0076] In a specific embodiment, the stripping device furthermore consists of at least one support means to support the rod wire at the location of the at least one rotor and thus to compensate for the pushing forces of the at least one cleaning pad on the rod wire and to maintain the wire in position. When the at least one cleaning pad is pushed against the rod wire in order thus to clean the metal wire efficiently, it is possible that the rod wire may be pushed sideways on account of the pushing force of the cleaning pad. By using a support means which will form a guide as it were against which or inside which the rod wire will be displaced, the rod wire will only experience a limited displacement due to the pushing force of the cleaning pad, thus resulting in an improved cleaning action of the at least one cleaning pad.

[0077] The method described herein comprises, in a step (c), the (in-line) application or coating of the rod wire. More particularly, the rod wire may be provided with a lubricant. This may be used to assist the wire drawing process or the rolling process and the possible stress relief. Suitable lubricating means are well-known to the person skilled in the art. In specific embodiments, the wire is provided with a drawing soap, with the active component of the soap mainly being calcium stearate, sodium stearate, or a combination of calcium stearate and sodium stearate. Preferably, the wire is provided with a lubricant before rolling or wire drawing the rod wire. The lubricant may be applied in a continuous manner by spraying, submerging, brushing, or other techniques which are known to the person skilled in the art.

[0078] The method described herein, in a step (d), comprises the (in-line) wire drawing or rolling of the rod wire. In this case, a drawn or rolled metal wire is obtained which may optionally be treated further (see below). Wire drawing processes or rolling processes for metal wires are well-known to the person skilled in the art. An elongation process may be performed by guiding the rod wire across at least two drawing rollers, with the second drawing roller having a diameter which is slightly larger than that of the first drawing roller, as a result of which the wire is subjected to plastic elongation. The difference in diameter causes tension on the rod wire.

[0079] Sometimes, the desired deformation can be achieved more easily by drawing the wire through at least one drawing die, or by rolling the wire through a set of rollers. When more than one wire drawing device is provided, lubricant will preferably be applied between every wire drawing device. The lubricant may in each case be the same lubricant or a different lubricant may be used for each wire drawing device. Preferably, the lubricant used and applied before the first wire drawing device will be a soap substantially consisting of calcium stearate, for every intermediate wire drawing device, the lubricant used will be a soap substantially consisting of sodium stearate, and for the last wire drawing device, the lubricant used will be an emulsion soap. In the case of an emulsion soap, the emulsion will be introduced in a tubular duct. As part of the application of the emulsion, the rod wire will be passed through the tubular duct in order thus to provide the rod wire with the emulsion on all sides. Preferably, it is possible not to use any soap during the last reduction step using a drawing die.

[0080] According to a preferred embodiment, the wire drawing device consists of a rotating drawing die holder and a drawing die. The drawing die may be cooled both directly and indirectly. The drawing die is cooled indirectly by rotation of the drawing die holder, in which case the cooling will cause an internal cooling in the drawing die. As a result thereof, the rod wire is cooled while moving through the drawing die. Preferably, the at least one wire drawing device is provided with a pressure set, so that the pressure set can build up additional pressure in order thus to support passing the rod wire and lubricant through the drawing die.

[0081] In a preferred embodiment, the method described herein is a method for cold-drawing a rod wire. In this case, the elongation process is carried out at a temperature below the recrystallization temperature of the metal. More particularly, the elongation process can be carried out at room temperature. Cold-drawing typically results in an increase of the tensile strength of the rod wire. In addition, during the step (d), a reduction in the diameter of the rod wire of 5 to 40% will be achieved when the rod wire moves through a first wire drawing device. Alternatively, it is possible that during the step (d) of wire drawing the rod wire, in each case an identical reduction in the diameter of the rod wire is achieved each time the rod wire moves through successive wire drawing devices. As an additional alternative, it is possible that, during the step (d) of the wire drawing of the rod wire, in each case a continuously decreasing reduction in terms of percentage of the diameter of the rod wire is obtained in each case when the rod wire moves through successive wire drawing devices.

[0082] The result of the elongation of the rod wire by the at least one wire drawing device is that a drawn or rolled metal wire is obtained, wherein the diameter of the drawn or rolled metal wire is preferably between 2.07 mm and 2.17 mm, preferably between 2.4 mm and 2.55 mm, between 2.7 mm and 2.9 mm and between 2.9 and 3.20 mm, between 3.25 mm and 3.5 mm, between 3.6 and 3.75 mm, between 3.90 mm and 4.15 mm, between 4.4 mm and 4.9 mm, or between 4.9 mm and 5.9 mm, or between 5.9 and 6.1 mm or between 6.1 and 7.2 mm or between 7.2 and 8.2 mm or between 8.2 and 10.2 mm, or between 10.2 and 12.3 mm or between 12.3 and 14.5 mm or between 14.5 and 20.5 mm, with the diameter having a tolerance of + / - 0.02 mm, + / - 0.03 mm or + / - 0.04 mm or + / - 0.06 or 0.1 mm or + / - 0.5 mm. Preferably, using the method, a metal wire is obtained, with the drawn or rolled metal wire with a certain diameter having a tensile strength which falls into a certain class: Diameter (mm)Tensile strength (N / mm 2< ) lower limitTensile strength (N / mm 2< ) upper limit2.0 - 3.07009503.0 - 4.06509004.0 - 5.05508305.0 - 20.0550700

[0083] Determining or measuring the diameter is preferably performed directly after the plastic elongation. Measuring the diameter may be effected in various ways.

[0084] In specific embodiments, the diameter is determined in an optical manner. This can be effected by directing a set of one or more light sources (for example laser bundles) in one or more directions at right angles to the wire and detecting the permeated light. Such an arrangement makes it possible to not only measure the diameter, but also the ovality and / or other parameters of the shape of the wire.

[0085] Suitable arrangements for measuring the diameter of the drawn or rolled wire are commercially available and can be obtained by a person skilled in the art.

[0086] In specific embodiments, the diameter may be determined in other ways, for example by means of the speed of the metal wire before and after elongation. It is possible to determine the lengthening of the wire, and thus also the corresponding reduction in diameter, from the change in speed. The speed of the metal wire may be determined via contact or non-contact measurements, as is known to the person skilled in the art. Suitable non-contact measuring techniques may comprise, for example, Doppler laser speed measurement. Optionally, several reference measurements of the wire diameter may be performed. As a result thereof, the diameter can be determined more precisely.

[0087] In specific embodiments, an additional monitoring of the wire diameter may be carried out by means of a wire diameter monitoring system.

[0088] The method described herein comprises, in a step (e), the (in-line) passing of the drawn or rolled metal wire across a return wheel device and / or through a wire straightener. The wire straightener is preferably composed of a first part consisting of a first set of wheels and a second part consisting of a second set of wheels, wherein each set in each case consists of at least three wheels.

[0089] If both a wire straightener and a return wheel device are provided, the wire straightener and return wheel device will have been placed in two different planes, so that the cast and helix of the drawn or rolled metal wire can be adjusted while the drawn or rolled metal wire is being passed through. Preferably, the diameter of the return wheel in the return wheel device is sufficiently large, while the wheels in the wire straightener are small compared to the diameter of the return wheel.

[0090] Inside the wire straightener, the wheels are arranged in such a way that upon contact of the advancing wire with a wheel, the wire is deflected from a linear course and in this case is depressed to a depression depth. In this case, the depression depth corresponds to the distance along which the wire is depressed, compared to a neutral state in which the wire is not deflected and would follow a linear course. Within one set of wheels, the wheels are typically distributed over a first row and a second row, so that when the wire is passed through the set, the wire successively comes into contact with a wheel from the one row and subsequently with a wheel from the other row. Upon contact with a wheel from the first row, the wire is bent in one direction, for example downwards, and upon contact with a wheel from the second row, the wire is bent in the opposite direction, for example upwards. Within one set of wheels, the wire may be depressed at every wheel to the same depression depth, or the depression depth may differ for each wheel, or the depression depth of some wheels may be the same and may be different for other wheels. If within one set of wheels, the wire is depressed at each wheel to the same depression depth, then this value is deemed to be the depression depth of the respective set of wheels of the wire straightener. If the wire straightener consists of a first part and a second part, the rotation axles of the wheels of the first part are preferably arranged horizontally, and the rotation axles of the wheels of the second part are preferably arranged vertically. For example, when passing the wire through the first set, it is deflected from the bottom to the top, and when passing the wire through the second set, it is deflected from the front to the back. When passing the wire through the first and second set of wheels, the depression depth of the first and second set may be the same or different. Typically, each set comprises several wheels, for example three, two of which are situated in one row and one of which is situated in the other row. In other examples, a set comprises five or seven wheels, with three or five wheels, respectively, being placed in a first row and two or four wheels, respectively, being placed in a second row. In yet other examples, a set comprises a large number of wheels, for example up to twenty wheels, distributed over two rows.

[0091] In specific embodiments, the wire straightener is used with a view to obtaining a desired cast and pitch of the wire, which are characteristic for the curvature and the degree of curling of the wire. Such parameters are important in order to be able to roll up a produced wire in a satisfactory manner, but even more important in order to be able to unroll it in a satisfactory manner. For example, on the one hand, the wire should be prevented from curling up too much like a spiral, but on the other hand, it also has to be possible to roll up the wire easily in accordance with a desired rolling-up diameter, and has to be easy to unroll. In such a case, the wire straightener is thus used to straighten the wire, i.e. to make it sufficiently straight and flat. With a view to straightening the wire, it typically suffices to adjust the wheels of the wire straightener in such a way that the wire is deflected or depressed only to a limited degree when being passed through the wire straightener. For example, there is hardly any depression, and the wire moves essentially closely past the wheels of the wire straightener. For example, when using the wire straightener as a straightener, the wheels are arranged in such a way that the depression depth at each of the wheels is at most 5 mm, for example at most 4 mm, for example at most 3 mm, for example at most 2 mm, for example at most 1 mm. In specific embodiments, the wire straightener for each of the wires to be produced is set as the straightener, thus always applying a limited depression depth. The latter may be the same for all wires, or may be different for different wires. In other embodiments, the wire straightener is only set as the straightener for certain wires to be produced, thus applying the limited depression depth.

[0092] In certain other embodiments, the wire is deflected or depressed to a greater degree when it is passed through a set of wheels of the wire straightener than is strictly necessary based on straightening the wire and obtaining the desired rolling and unrolling behaviour. For example, the wheels of a set are arranged in such a way that the depression depth at one or more of the wheels, or at each of the wheels, is at least 2 mm, for example at least 3 mm, for example at least 4 mm, for example at least 5 mm, for example at least 6 mm. For example, a depression depth is used which has at least the abovementioned value, and is at most 15 mm.

[0093] Bringing about a greater deflection or depression using at least one of the wheels of the wire straightener has the advantage that this produces a greater degree of deformation of the wire, so that, due to the Bauschinger effect, a softer wire is obtained than when no such (strong) deformation of the wire is applied. In this case, the expression a softer wire refers to a wire whose yield point Re or 0.2% yield stress, and the tensile strength Rm are sufficiently low, so that the resulting wire is sufficiently ductile and readily deformable. This is in contrast with a steel wire which has a greater hardness and strength, but lower ductility, and is less easily deformed.

[0094] In other words, in such embodiments, the wire straightener, or a set thereof, is used as a so-called softener, in order to achieve a desired - sufficiently low - wire strength. In such cases, the wire straightener or the set then typically has two functions, namely as a straightener for bringing about the desired winding and unwinding behaviour, and as a softener in order to achieve the desired yield point and tensile strength. The use of the wire straightener as a softener has the advantage that a sufficiently deformable wire is obtained, which is important for applications in which the metal wire will be used, for example, in woven nets or wire cable ducts. In addition, it makes it possible to use less expensive types of steel, for example produced from scrap, or less expensive scrap, without having to use softer, but more expensive types of material made from iron ore or more expensive scrap.

[0095] When using the wire straightener or a set of wheels inside the wire straightener as softener, various embodiments are possible with regard to the depression depth of the respective wheels. For example, a sufficiently large depression depth may be used for each of the wheels, for example the same large depression depth for each of the wheels, or a different (large) depression depth for each of the wheels, or a (large) depression depth which is the same on some wheels and is different on some wheels. In other examples, only a limited depression or none at all is used on one or more wheels, while a sufficiently large or even a very large depression depth is used on one or more other wheels.

[0096] In certain embodiments, the wire straightener for each of the wires to be produced is set as a softener, with a sufficiently large depression depth being applied on at least one of the wheels of the wire straightener for every wire. This setting of depression depth(s) may be the same for all wires, or may be different for different wires. In other embodiments, the wire straightener is only set as a softener for certain wires to be produced.

[0097] In certain embodiments, the wire straightener comprises two sets of wheels, and each of the sets is used as a softener. For example, the depression depth of each of the wheels in the first and second set is in each case at least 2 mm, for example at least 3 mm, for example at least 4 mm, for example at least 5 mm, for example at least 6 mm. For example, a depression depth is used which has at least the abovementioned value for each of the sets, and is at most 15 mm. In this case, the same or a different setting of depression depth(s) may be used for the first and the second set. In certain other embodiments, only one of the sets is used as a softener, in which a depression depth is used on at least one of the wheels which is greater than or equal to a threshold value, while the other set is used as a straightener, in which a depression depth is used on each of the wheels which is smaller than the threshold value. For example, the threshold value is 2 mm or 3 mm or 4 mm or 5 mm or 6 mm. For example, the first set of wheels of the wire straightener is set as a straightener, having a limited depression depth, and the second set of wheels is set as a softener, having a greater depression depth. In this case, the desired strength properties and deformability are brought about when a wire is passed through the first set, and the wire is subsequently finally straightened when it is passed through the second set before being rolled up.

[0098] In specific embodiments, the depression depth on each of the wheels of the wire straightener is at most 15 mm, for example at most 10 mm. In this way, the wire straightener can be used as a softener, but this also prevents an undulating pattern from becoming visible in the resulting wire due to excessive deformation. It is thus also prevented that the wire becomes excessively hot, as excessive heating may result in the soap film from coming off and soiled patches being created on the wire.

[0099] In certain embodiments, at least one of the wheels of the wire straightener is arranged so as to be movable, so that by displacing the one or more movable wheels, the depression depth of the metal wire can be varied. For example, each of the wheels is arranged so as to be movable, so that they are individually displaceable. For example, the wheels of one set are displaced together, so that in each case the same depression depth is achieved across all wheels of the set. Moving of the wheels typically takes place according to a linear translation, in a direction substantially at right angles to the feed-through direction or moving direction of the wire. In this case, wheels of opposite rows in a set are moved towards each other or away from each other. For example, in a set, the wheels from a top row are moved down and the wheels from the bottom row are moved up, so that the mutual distance between the bottom and top row decreases and a greater depression depth of the wire is obtained. The displacement of the wheels may be brought about in a mechanical way and manually, or may be actuated by means of an actuator in a way known to the person skilled in the art.

[0100] In specific embodiments, each set of wheels of the wire straightener is used as a straightener for certain metal wires, using a limited depression depth for each of the wheels, and one or more sets of wheels of the wire straightener are used as a softener for other metal wires, using a greater depression depth on at least one of the wheels of the set. For example, with a depression depth on all wheels smaller than a threshold value, the wire straightener or the set is set as a straightener, and with a depression depth on at least one of the wheels greater than a threshold value, the wire straightener or set is set as a softener. This threshold value is, for example, 2 mm or 3 mm or 4 mm or 5 mm.

[0101] In specific embodiments, the depression depth of the respective wheels of the wire straightener is set on the basis of one or more wire parameters. In this case, it is possible to set the same depression depth for each of the wheels, or different depression depths may be set for the various wheels. The wire parameters are for example characteristic of the initial wire at the start of the production process, and / or are characteristic of the desired wire at the end of the production process. Parameters characteristic of the initial wire are, for example, the type of steel or initial wire diameter. Parameters characteristic of the desired wire are, for example, strength parameters such as the desired tensile strength, desired yield point, desired hardness, or form parameters, such as the desired wire diameter, pitch, helix or cast. In such embodiments, the wire straightener is thus adjustable, with a set value for the wheels corresponding to the desired depression depth being determined for each wheel or for each set of wheels, by selecting a set value on the basis of wire parameters. Selection of the set value may be carried out on the basis of one of said parameters, for example the desired tensile strength, or on the basis of a combination of several of said parameters. Such a selection may be performed manually or automatically. After selection of the set value(s) for the respective wheels has taken place, each of the wheels is set to the selected depression depth. In this case, it is possible that, depending on the parameters, all wheels are set to a limited depression depth, so that the wire straightener is purely used as a straightener, or - with other applicable parameters - one or more or all wheels of the wire straightener are set to a great depression depth, so that the wire straightener, or at least a set thereof, is used as a softener.

[0102] The use of the wire straightener, and the adjustment thereof, as a straightener and / or as a softener, has the advantage that it is possible to produce the desired strength properties and the desired winding behaviour and unwinding behaviour in a simple mechanical way. Performing a large deformation with a wire straightener at the end of the production process carries with it a certain risk, because deformations in the wire might remain visible or the wire might be soiled due to excessive heating of the wire and the soap coming off. However, surprisingly, it has been found that by selecting the optimum depression depths, such a risk is limited and at the same time the desired strength and winding properties are produced.

[0103] In the context of the overall production process, it was found in particular that it becomes possible, through a unique combination of subprocesses, to provide a production process which, on the one hand, enables meeting the stringent quality standards for metal wires to be produced and, on the other hand, using simple, mechanical subprocesses. This avoids, for example, steps using pickling or annealing, which contribute to meeting quality standards, but render the production process expensive and / or polluting. It was found in particular that stripping can be performed mechanically by using brushes and / or rotating wheels, in combination with a wire straightener further downstream in the production line, used to straighten and / or soften the wire. In this way, stresses which are induced during mechanical stripping and / or during wire drawing and which cause material reinforcement and insufficient deformability, are neutralized again by means of the wire straightener, due to the Bauschinger effect, so that a sufficient degree of softness and deformability is achieved. The combination of simple mechanical processes which has been discovered thus makes it possible to push the wire properties in the direction of the desired properties in a unique way and to meet stringent quality standards - which may, in addition, differ depending on the application.

[0104] In specific embodiments, the wire straightener is cooled. Typically, the wire heats up during the production process, for example up to 50°C when it reaches the winding coil. In particular when the wire straightener is set as a softener, this heating up is even greater, for example an additional heating up of approximately 15°C, to 65°C during winding up. Excessive heating up of the wire may be disadvantageous, since as a result thereof there is a risk of the soap layer breaking off and breaking away, and leads to dirty wheels. The latter possibly results in dirt accumulating on the wire, which is unacceptable. In certain embodiments, cooling ducts are provided in the wheels of the wire straightener, wherein a cooling agent, for example cooling water, is passed through the cooling ducts. There is, for example, one cooling duct in every wheel, which extends along the rotation axle of the wheel. In this case, the cooling agent may flow, for example, from the front of a wheel to the rear, thereafter to the rear of a subsequent wheel, etc. In specific embodiments, the cooling of the wire straightener is brought about by placing a housing around the first and / or second set of wheels, and passing a cooling agent, for example cooling air, through the housing. A combination of cooling measures, wherein for example a first cooling agent is passed through cooling ducts in the wheels, and a second cooling agent is passed through a housing around the wire straightener, is also possible.

[0105] As a last step (f) in the method described herein, the drawn or rolled metal wire is wound up onto a coil. To this end, a winding device is preferably provided wherein a wire guide is positioned for the winding device in order thus to guide the metal wire during winding up. Preferably, the residual lubricant content of the applied lubricant after the winding up of the drawn or rolled metal wire is at most 3.0 g / m 2< . In certain cases, the residual lubricant content is limited even more, for example to 1.5 g / m 2< or to 0.5 g / m 2< .

[0106] In specific embodiments, the method described herein may comprise a passivating step. Such a passivating step will typically take place before or after step (e). Passivating leads to the spontaneous formation of a hard non-reactive surface film which slows down further corrosion, and may be achieved by submerging the wire in one or more passivating solutions, as known to the person skilled in the art. Passivating is usually performed after plastic elongation and optionally drawing and / or stress relief of the wire.

[0107] In a specific embodiment, the present invention also provides a metal wire manufactured using an embodiment of a method as described herein.EXAMPLES

[0108] Fig. 1 shows a diagrammatic representation of a specific embodiment of the method described herein for drawing or rolling a metal wire.

[0109] The method comprises, in a first step (1001), providing a rolled-up rod wire, and the continuous unwinding of the rod wire. The wire is conveyed through the various steps of the method at a speed of approximately 7 m / s (typically between 1m / s and 15m / s). In a first step (1002), the circumference of the wire is stripped. In a next step (1003), a lubricant is applied to the surface of the stripped rod wire. Subsequently, the rod wire is drawn (1004) by passing the rod wire over at least one wire drawing device which exerts a force on the rod wire. In this case, the wire is reduced by approximately 5% to 40%. Alternatively, the wire is rolled by drawing the wire through a rolling head. In a next step (1005), the drawn or rolled metal wire is passed through a wire straightener and / or return wheel device, wherein the cast and helix of the drawn or rolled metal wire may be adjusted. In a last step (1006), the metal wire is rolled up.

[0110] Fig. 2 diagrammatically shows the rod wire 5 which has been wound onto a rod wire bundle 6 and placed on two vertical towers 7. An end of the first rod wire bundle 6a is connected to an end of the second rod wire bundle 6b. Preferably, the ends are welded to each other 8 in order thus to be able to create a continuous process and to supply the rod wire 5 in an uninterrupted manner to the stripping device. The rod wire 5 preferably consists of a low-carbon steel, such as of the types of SAE 1004 to SAE 1020 metal. To ensure good galvanization, the silicium content present in the rod wire will either be at most 0.03% or will be at least 0,14%.

[0111] Fig. 3 shows a stripping device 10, wherein a first set of rotating wheels 11, 12, 13, 14, 15 is provided, so that the rod wire 5 can be guided along the rotating wheels 11-15 in an S-shaped course. The rotation axles of the rotating wheels 11-15 are positioned horizontally. The rotating wheels 11, 12 and 15 are arranged so as to be movable and can be raised and / or lowered by means of a controllable mechanism 16 in order thus to modify the course of the rod wire 5, but this is not imperative. The rotating wheels 13 and 14 are fitted on a movable disc 17, wherein the movable disc or background disc 17 may be rotated about its centre point. Rotating the movable disc 17 results in the course, for example the S-shaped course which is situated between the rotating wheel 12 and the rotating wheel 15, being changed. Changing the course means that the rod wire 5 will be bent in a different way, as a result of which the outer mill scale will crack and / or break off in a different way. In addition, due to the position of the various rotating wheels 11,12,13,14,15 with respect to each other, a first reduction of the diameter of the rod wire 5 can already be obtained.

[0112] Fig. 4 shows a second set of rotating wheels 21, 22, 23 of the stripping device 10 and thus forms a second part of the stripping device 10. (the entirety may also be arranged in one machine). The rod wire 5 coming from the rotating wheel 15 of the first set will then be bent further by means of the second set of rotating wheels 21-23 in order to break the mill scale further and to remove it. The rotation axles of the rotating wheels 21-23 are essentially arranged vertically, typically resulting in a different bend than is the case when bending about the first set of rotating wheels 11-15 which are essentially arranged horizontally. In an alternative arrangement, the rotating wheels may also be arranged at an angle of, for example, 45° and -45°, as a result of which the mill scale can be removed from the arrangement more easily.

[0113] Fig. 5 shows a helical brush 25 which is arranged in a swinging manner, so that it can perform a pulsating and vibrating movement. Such a helical brush 25 is a brush provided with a plurality of small metal wires, wherein the brush is configured in a helical shape through which the rod wire 5 will be passed. The helical brush 25 is arranged in a swinging manner, with the helical brush 25 making a reciprocating or pulsating movement. Preferably, the helical brush 25 will thus perform a vibrating movement. A linear motor or a pneumatic cylinder (not shown) which cause the movements of the helical brush 25 may be provided. Due to this vibrating and pulsating movement, the helical brush 25 will brush the surface of the rod wire 5 efficiently and is self-cleaning. The helical brush 25 may be arranged at any desired position along the course through the stripping device 10. Preferably, a first helical brush 25 is provided after the second set of rotating wheels 21-23 and a second helical brush 25 is provided before the first soap reservoir 40 (see Fig. 8). By using such helical brushes 25, the surface of the rod wire 5 will be cleaned in an optimum manner and any partly detached mill scale particles or other impurities will be removed before lubricant is applied to the surface of the rod wire 5.

[0114] Fig. 6 shows a rotor device 30 which forms part of the stripping device 10, in which cleaning pads 32, 34 may be provided. The rod wire 5 is inserted in the rotor device 30 on a first side, is then passed through the rotor device 30, after which the rod wire 5 will exit the rotor device 30 again on a second side, opposite the first side. The rotor device 30 may consist of one or more rotors which rotate about the rod wire. Cleaning pads are fitted in the rotor device 30, with the cleaning pads being arranged in such a way that the rod wire 5 is in contact with the cleaning pads. The cleaning pads are pushed against the rod wire 5 with a certain force in order to ensure satisfactory action. To prevent the rod wire 5 from following an undulating course as a result of the force exerted on of the cleaning pads, the rotor device 30 may be provided with one or more support means, along which the rod wire 5 will move. Using such support means at regular intervals within the rotor device 30 makes it possible to prevent the undulating movement of the rod wire 5 caused by the cleaning pads 32, 34 being pushed from being such that optimum cleaning by the cleaning pads 32, 34 is no longer possible.

[0115] Fig. 7A shows a first embodiment of the cleaning pads 32, Fig. 7B shows an alternative embodiment of the cleaning pads 34. The cleaning pad 32 as illustrated in Fig. 7A is a mainly cylindrical tube, in which a plurality of small metal wires are contained in a synthetic polymer along substantially their entire length. Preferably, the front of the cleaning pad 32, being the side which will be brought into contact with the moving rod wire 5, is provided with a groove 33. While it is being operated, the rod wire 5 will move in the groove 33 and, due to the shape of the groove, a larger surface of the rod wire 5 can be brought into contact with the small metal wires and polymer surface of the cleaning pad 32.

[0116] Fig.7B illustrates an alternative embodiment of a cleaning pad 34, in which the contact surface of the cleaning pad 34 which will be brought into contact with the advancing rod wire 5 is longer compared to the contact surface of the cleaning pad 32, as illustrated in Fig. 7A. The cleaning pad 34 is likewise provided with a groove 35, so that the rod wire 5 can again be cleaned in an optimum manner when the rod wire 5 is passed through the groove 35 of the cleaning pad 34. The use of an elongate shape, such as the cleaning pad 34, versus a round shape, such as the cleaning pad 32, ensures that less material is required for constructing the cleaning pad 34. The fact is that only the zone of the grooves 33, 35 will come into contact with the rod wire 5.

[0117] Normally, the zones above and below the grooves 33, 35 will not be brought into contact with the rod wire 5 and will consequently not contribute to cleaning of the rod wire 5, as a result of which the life of the cleaning pad is significantly increased.

[0118] Fig. 7B also shows a holder 36 for the cleaning pad 34. The holder 36 has a shape which is similar to the shape of the cleaning pad 34, so that the cleaning pad 34 can be introduced into the holder 36 and can be held there when the rod wire 5 runs in the groove 35. The holder 36 is provided with two supports 37 which are arranged around pivot axle 38. A bracket 39 to which the pivot axle 38 is attached, is mountable to the rotor device 30. Depending on the diameter of the rod wire 5, it may be necessary to position the cleaning pad 34 closer to or further away from the rod wire 5, and the holder 36 and the supports 37 may be repositioned by pivoting the supports 37 about the pivot axle 38.

[0119] During stripping, the rod wire 5 may heat up, due to bending of the metal wire 5 around the rotating wheels 11-15 and 21-23 and / or due to friction of the cleaning pads 32, 34 and / or the helical brushes 25.

[0120] Fig. 8 shows a first soap reservoir 40 provided with lubricant for applying the lubricant to the surface of the stripped rod wire 5 and a first drawing die holder 50 for drawing the rod wire 5. The lubricant provided in the first soap reservoir 40 is preferably a soap whose active component consists mainly of calcium stearate or a calcium / sodium stearate mixture. The rod wire 5 is first passed through the first soap reservoir 40, after which the rod wire is supplied to the inlet side of the drawing die holder 50. When the stripped rod wire 5 is passed through the inlet side of the drawing die holder 50, the diameter of the rod wire will decrease and ultimately the drawn metal wire 5' will have the diameter of the outlet side of the drawing die 54.

[0121] As has already been indicated, the temperature of the rod wire 5 will increase during the wire drawing. In order to lower this temperature, the drawing die holder 50 is cooled directly or indirectly. As a result thereof, the drawing die holder 50 is cooled internally.

[0122] Fig. 9 shows a second soap reservoir 60 and a second rotating capstan 70 for drawing the drawn metal wire 5' further. Before the drawn metal wire 5' undergoes an additional reduction as a result of the second reduction step, the drawn metal wire 5' will again be passed through a second soap reservoir 60. The lubricant provided in the second soap reservoir 60 is preferably a soap whose active component consists mainly of sodium stearate. The second capstan 70 is a cylinder around which the drawn metal wire 5' runs. The cylinder is arranged at an angle of inclination and the drawn metal wire 5' will be supplied to the cylinder at the bottom, run at least 1x around the cylinder and leave the cylinder surface again, for example, halfway along the cylinder. By running around this cylinder and simultaneously drawing on the drawn metal wire 5', the diameter of the drawn metal wire 5' will decrease further before it is passed through the second soap reservoir 60 and drawing die. It is possible to provide several soap reservoirs and rotating drums in order thus to achieve the desired diameter of the drawn metal wire 5'. In that case, the lubricant in the additional soap reservoirs is preferably a soap whose active component mainly consists of sodium stearate.

[0123] Fig. 10 shows an example of emulsion reservoir 80 for applying the emulsion to the circumference or surface of the drawn metal wire 5', before the drawn metal wire 5' undergoes its final reduction.

[0124] The emulsion reservoir 80 is provided with a tubular duct 82 through which the rod wire will be passed. A supply line 84 provides an emulsion to the tubular duct 82 in order thus to provide the tubular duct 82 with sufficient lubricating emulsion.

[0125] Consequently, the drawn metal wire 5' will be passed through the tubular duct 82 while the emulsion is being applied in order thus to provide the drawn rod wire 5' with the emulsion on all sides.

[0126] Fig. 11 shows an alternative for a reduction using a drawing die, namely a roller block: the wire is surrounded by at least 2 rollers. The inlet diameter of the incoming wire is greater than the passage opening which is formed by the opening between the rollers. As a result thereof, the wire is reduced, and a longer, thinner wire is produced. The rollers may or may not be cooled, by means of, for example, cooling ducts in the shafts of the rollers. Use may be made of one set of reducing rollers, or successive sets of reducing rollers. The passage opening of the rollers, defines the shape of the section of the wire. This may be, for example, round, but also triangular.

[0127] Fig. 12 shows a wire straightener 90,92 and a return wheel device 94 for straightening the drawn or rolled metal wire 5'. The wire straightener is composed of a first part 92 consisting of a first set of wheels and a second part 90 consisting of a second set of wheels, wherein each set in each case consists of at least three wheels, for example five or seven wheels. The rotation axles of the five or seven wheels of the first part 92 are, for example, arranged horizontally, whereas the rotation axles of the seven wheels of the second part 90 are arranged vertically. The wire straightener 90, 92 and return wheel device 94 are arranged in two different planes, so that the cast and helix of the metal wire 5' can be adjusted while the drawn or rolled metal wire 5' is being passed through. Preferably, the diameter of the return wheel in the return wheel device 94 is sufficiently large, whereas the wheels in the wire straightener 90, 92 are small in comparison to the diameter of the return wheel 94, this in combination with the tensile strength of the wire. As a result thereof, the internal stresses are redistributed and the cast and pitch can be adjusted.

[0128] Fig. 13 to 15 show an alternative embodiment of a wire straightener, in which the figures show a first set of wheels 98. The first set consists of seven wheels, arranged in two rows of four and three wheels, respectively. The wire straightener furthermore also comprises a second set consisting of seven wheels. Fig. 14 shows a detail, which makes it clear that the metal wire is deflected as a result of contact with the wheels and is depressed as far as a depression depth 102. In this case, the depression depth 102 corresponds to the distance of the point at which the wire is deflected the most, to a reference line 101, wherein the reference line corresponds to a neutral state in which the wire is not deflected and follows a linear course. Fig. 13 shows that the wire straightener 98 is adjustable, wherein the wheels of the set can be displaced along a direction 100, substantially at right angles to the linear supply course 99 of the wire. By displacing the wheels, the depression depth brought about by means of the wire straightener 98 can be changed. In this way, the wire straightener may be set as a straightener, with a limited depression depth of the wire, or as a softener, with a larger depression depth of the wire. In addition, Fig. 15 illustrates that the wheels of the wire straightener 98 are provided with cooling ducts 103. In this case, each wheel comprises a cooling duct which extends along its rotation axle. As is illustrated by means of the arrows 104, a cooling agent, for example water, is successively passed through the ducts of successive rollers in the same row.

[0129] By means of an arrangement comprising a wire straightener as shown in Fig. 13, a number of tests were performed in order to verify the effect of the depression depth on the obtained yield point and tensile strength. From these, it was inferred that, for an inexpensive type of steel, such as SAE-1008, and a regular initial wire diameter of 5.50 mm, a yield point and tensile strength are obtained which are 70 to 80 MPa lower if the first set of wheels is set as a softener, with a depression depth of 2 to 3 mm, compared to a situation in which the two sets of wheels are set as a straightener. By additionally setting the second set as a softener, with a depression depth of 2 to 3 mm being used in both sets of wheels, an additional reduction of approximately 20 MP in yield point and tensile strength was obtained compared to the situation in which only the first set was set as a softener.

[0130] Fig. 13 shows a wire guide 95 and the coil 96 for winding up of the final produced and drawn or rolled metal wire 5'. The wire guide 95 is positioned for the winding device 97 in order thus to guide the metal wire 5'while it is being wound up around the coil 96.

[0131] The separate components as illustrated in Figs. 2 to 13 may be placed in line as follows, resulting in a continuous process for manufacturing the drawn or rolled metal wire 5': the rolls of metal wire which are wound onto a rod wire bundle 6 and have been placed on vertical towers 7, as illustrated in Fig. 2; the first set of rotating wheels 11-15 of the stripping device 10, as illustrated in Fig. 3; the second set of rotating wheels 21-23 of the stripping device 10, as illustrated in Fig. 4; a first helical brush 25, as illustrated in Fig. 5; a rotor 30 of the stripping device as illustrated in Fig. 6, in which cleaning pads 34 as illustrated in Fig.7B have been arranged; a first soap reservoir 40 and a first drawing die holder 50, as illustrated in Fig. 8; a second soap reservoir 60 and a second drawing die holder 50 and a capstan 70, as illustrated in Fig. 9; a third soap reservoir 60 and a third drawing die holder 50 and a third capstan 70; an emulsion reservoir 80, as illustrated in Fig. 10 a return wheel device 94 and a wire straightener 90, 92, as illustrated in Fig. 12 a wire guide 95 and coil 96, as illustrated in Fig. 13.

[0132] As an alternative to a first soap reservoir with a drawing die holder and / or a second soap reservoir with a drawing die holder, roller blocks may be used.

Examples

examples

EXAMPLES

[0108]Fig. 1 shows a diagrammatic representation of a specific embodiment of the method described herein for drawing or rolling a metal wire.

[0109]The method comprises, in a first step (1001), providing a rolled-up rod wire, and the continuous unwinding of the rod wire. The wire is conveyed through the various steps of the method at a speed of approximately 7 m / s (typically between 1m / s and 15m / s). In a first step (1002), the circumference of the wire is stripped. In a next step (1003), a lubricant is applied to the surface of the stripped rod wire. Subsequently, the rod wire is drawn (1004) by passing the rod wire over at least one wire drawing device which exerts a force on the rod wire. In this case, the wire is reduced by approximately 5% to 40%. Alternatively, the wire is rolled by drawing the wire through a rolling head. In a next step (1005), the drawn or rolled metal wire is passed through a wire straightener and / or return wheel device, wherein the cast and helix of ...

first embodiment

[0115]Fig. 7A shows the cleaning pads 32, Fig. 7B shows an alternative embodiment of the cleaning pads 34. The cleaning pad 32 as illustrated in Fig. 7A is a mainly cylindrical tube, in which a plurality of small metal wires are contained in a synthetic polymer along substantially their entire length. Preferably, the front of the cleaning pad 32, being the side which will be brought into contact with the moving rod wire 5, is provided with a groove 33. While it is being operated, the rod wire 5 will move in the groove 33 and, due to the shape of the groove, a larger surface of the rod wire 5 can be brought into contact with the small metal wires and polymer surface of the cleaning pad 32.

[0116]Fig.7B illustrates an alternative embodiment of a cleaning pad 34, in which the contact surface of the cleaning pad 34 which will be brought into contact with the advancing rod wire 5 is longer compared to the contact surface of the cleaning pad 32, as illustrated in Fig. 7A. The cleaning pad ...

Claims

1. Method for manufacturing a drawn or rolled metal wire, comprising the next steps: (a) arranging a rod wire (5) having a diameter of between 4 mm and 22 mm, the rod wire (5) being provided on a roll (6) with a cast of between 600 mm and 5,000 mm; (b) stripping the rod wire (5) by means of a stripping device (10), the stripping device (10) comprising: • a first set of at least two rotating wheels (11, 12, 13, 14, 15), wherein the rotating wheels (11-15) are arranged in such a way that the rod wire (5) follows an S-shaped course, and • at least one rotor (30) provided with at least one cleaning pad (32, 34), wherein the rotor (30) is configured to rotate about the rod wire (5), and wherein the at least one cleaning pad (32, 34) is in contact with the rod wire (5) in order thus to brush across the outer layer of the rod wire (5); (c) applying a lubricant onto the surface of the stripped rod wire (5) and wherein the lubricant is applied to the surface of the rod wire before said rod wire (5) is drawn or rolled, so that the wire drawing and / or the rolling is performed on a lubricated rod wire (5); (d1) wire drawing said rod wire (5) by means of at least one wire drawing device comprising the combination of a drawing die holder and a capstan (50, 70), and / or (d2) wire rolling said rod wire (5) by means of at least one rolling head, wherein a lubricant may be applied for each rolling head; (e) passing the drawn or rolled metal wire through a return wheel (94) and / or a wire straightener (90, 92), wherein the wire straightener (90, 92) consists of at least three wheels; and (f) preferably winding up the drawn or rolled metal wire onto a coil (96) by means of a winding device (97), wherein a wire guide (95) is positioned in front of the winding device (97).

2. Method according to one of the preceding claims, wherein the rod wire (5) consists of a low-carbon steel, preferably from the types of metal SAE 1004 to SAE 1020, and wherein the silicium content in the rod wire (5) contains at most 0.03% Si or wherein the Si content is at least 0.14%, and wherein the rolled or drawn metal wire, depending on the diameter, has a tensile strength in accordance with the following table: Diameter (mm)Tensile strength (N / mm2) lower limitTensile strength (N / mm2) upper limit2.0 - 3.07009503.0 - 4.06509004.0 - 5.05508305.0 - 20.05507003. Method according to one of the preceding claims, wherein the at least two rotating wheels (11-15) are arranged so as to be movable, and wherein the positions of the rotating wheels (11-15) are adjustable with respect to each other in order thus to be able to modify the S-shaped course, and wherein the rotating wheels (13, 14) are mounted on a movable background disc (17), and wherein the background disc (17) is configured in such a way that the position of the background disc (17) will determine the S-shaped course.

4. Method according to one of the preceding claims, wherein the at least two rotating wheels (11-15) are arranged so as to be movable, and wherein, depending on the position of the rotating wheels (11-15) relative to each other, the rotating wheels (11-15) can bring about a reduction of the diameter of the rod wire (5).

5. Method according to one of the preceding claims, wherein the stripping device (10) furthermore consists of a second set of rotating wheels (21, 22, 23), the second set of rotating wheels (21-23) consists of at least three wheels, wherein the rotation axles of the wheels (11-15) of the first set are essentially arranged horizontally and the rotation axles of the three wheels (21-23) of the second set are essentially arranged vertically.

6. Method according to one of the preceding claims, wherein the stripping device (10) furthermore consists of at least one helical brush (25), and wherein the at least one helical brush (25) is preferably arranged after the at least one rotor (30) and / or before the application of the lubricant on the surface of the stripped rod wire (5), and wherein the helical brush (25) is arranged in a swinging manner and / or is capable of performing a pulsating and / or vibrating movement.

7. Method according to one of the preceding claims, wherein the stripping device (10) consists of at least two rotors (30), and wherein the rotors rotate in the same direction or wherein the rotors rotate in an opposite direction, and wherein the stripping device (10) furthermore consists of at least one support means to support the rod wire (5) at the location of the at least one rotor (30) in order thus to compensate for the pushing forces of the at least one cleaning pad (32, 34) on the rod wire (5).

8. Method according to one of the preceding claims, wherein the at least one cleaning pad (32, 34) is provided with a plurality of metal wires which are contained in a synthetic polymer along substantially the entire length, and wherein the at least one cleaning pad (32, 34) is provided with an indentation, preferably along the entire length of the at least one cleaning pad, wherein the rod wire is passed through the indentation (33, 35), and wherein the at least one cleaning pad (32, 34) cleans the rod wire (5) and supports it during cleaning.

9. Method according to one of the preceding claims, wherein the method comprises passing the drawn or rolled metal wire through a wire straightener (90, 92), and the wire straightener (90, 92) consists of a first part (90) provided with a first set of at least three wheels and a second part (92) provided with a second set of at least three wheels, wherein the rotation axles of the three wheels of the first part (92) are arranged horizontally, and wherein the rotation axles of the three wheels of the second part (94) are arranged vertically.

10. Method according to one of the preceding claims, wherein the method comprises passing the drawn or rolled metal wire through a wire straightener (90, 92), wherein the wire is depressed up to a depression depth by the respective wheels of the wire straightener, and wherein, in one or more sets of wheels of the wire straightener, the depression depth of each of the wheels is at most 5 mm, for example at most 4 mm, for example at most 3 mm, for example at most 2 mm, for example at most 1 mm, so that the respective set of wheels is set as a straightener.

11. Method according to one of the preceding claims, wherein the method comprises passing the drawn or rolled metal wire through a wire straightener (90, 92), wherein the wire is depressed up to a depression depth by the respective wheels of the wire straightener, and wherein, in one or more sets of wheels, the depression depth of at least one of the wheels is at least 2 mm, for example at least 3 mm, for example at least 4 mm, for example at least 5 mm, for example at least 6 mm, so that the respective set is set as a softener.

12. Method according to one of preceding claims, wherein at least one of the wheels of the wire straightener is arranged so as to be movable, so that the depression depth of the metal wire can be varied by displacing the one or more movable wheels.

13. Method according to Claim 12, wherein the depression depth of the movable wheels of the wire straightener is adjusted on the basis of one or more wire parameters, for example characteristic of the desired strength or softness of the metal wire.

14. Method according to one of preceding claims, wherein the wire straightener is cooled.

15. Method according to one of the preceding claims, wherein the residual lubricant content of the applied lubricant after winding up the drawn metal wire is at most 3.0 g / m2.

Images