FR2528734A1 - PROCESS AND MACHINE FOR THE CONTINUOUS AND DRY STRETCHING OF METALLIC WIRES - Google Patents

Abstract

THE MACHINE INCLUDES A FEEDING RACK 22 FOR WINDING THE WIRE 11 TO BE STRETCHED; MECHANICAL DEOXIDIZING MEANS FOR REMOVING THE OXIDE LAYER FROM THE SURFACE OF SAID WIRE; SURFACING TREATMENT MEANS INCLUDING A DIE FOR APPLYING UNDER PRESSURE A POWDERED LUBRICATING SURFACING AGENT 28 TO THE SURFACE OF SAID WIRE; LUBRICATION TREATMENT OF THE DRY TYPE PRECEDING THE STRETCHING; A DRAWING DIE 38 FOR STRETCHING THE WIRE WHICH HAS BEEN SUBJECTED TO LUBRICATION; A SURFACE FAULT DETECTOR 40 FOR DETECTING FAULTS IN THE SURFACE OF THE STRETCHED WIRE; AUTOMATIC REPAIR MEANS 42 FOR REMOVING THE DEFECTIVE SURFACE PARTS OF THE SAID STRETCHED WIRE; A CONTROL UNIT WHICH RESPONDS TO A SIGNAL FROM THE SAID SURFACE FAULT DETECTOR Sends A REPAIR SIGNAL TO THE SAID MEANS OF AUTOMATIC REPAIRS; AND, WINDING MEANS 44 FOR WINDING UP THE REPAIRED WIRE, ALL THE COMPONENTS OF THE SAID MACHINE, EXCEPT THE SAID CONTROL UNIT, BEING ARRANGED CONSECUTIVELY IN SERIES. APPLICATION TO THE PRODUCTION OF METAL WIRES AND STEEL BARS.

Description

The present invention relates to a method and a machine for

stretch continuously and dry

  wire or steel bars which are

  Briefly in the sequel are "threads".

  As a general example of a second machining operation of a wire intended to be cold forged to produce screws or nuts, there may be mentioned a

  method in which the wire is etched in a solution

  acidification, in order to deoxidize it, that is to say,

  get rid of its superficial layer of oxide.

  Then, the yarn thus stripped is treated with a lubricant.

  and then undergoes a preliminary stretching

  After this, the stretched wire is subjected to

  spheroidisation in order to eliminate the hardening

  Wearable Mechanics Resulting from the Stretching Process The stranded wire is stripped and then treated with a lubricant at a second stage before undergoing a secondary stretching process called a "finishing pass".

("skin pass").

  In the prior art, the treatment of

  stripping, surfacing treatment for lubricating

  The cation itself is part of a batch process in which a wire wound is suspended by means of a C-hook, so that it may be consecutively immersed and transferred inside and out of the bath containing the different treatment liquids It in

  As a result, this batch process has

  In the first place, productivity is low, which raises the cost; the elimination or disposal of the different treatment liquids entails additional costs which are high because of the need to avoid polluting the environment; the

  working conditions are not always satisfactory.

  because the treatments are of the "wet" or "wet" type; to which is added that the control of the product over the whole length is difficult. More specifically, liquid zinc phosphate is used by the prior art as a lubricating surface agent or a liquid prepared by dissolving either a powdered metal soap or a mixture of lime and metallic soap is used for this purpose. Furthermore, the wire to be cold forged is surface treated with a lubricant, i.e., with zinc phosphate which has excellent lubricating properties.

  expensive because the lubricant used for labeling

  rage affects, as it is, the necessary lubrication

  to perform cold forging.

  -15 On the other hand, given the increasingly stringent quality requirements of recent years, the detection and repair of defects, (straws, creeks, etc.) present in the drawn wire become

  increasingly restrictive Or, in an embarrassing way

  The detection and automatic repair of these defects during manufacture are extremely difficult, so that until now they have been carried out only separately. More precisely, after the drawn wire has been reeled up. , it detects its defects, during a finishing step, using a

  non-destructive or destructive detector or they are

  to the naked eye, if they are located on the surface

  For this reason, this external process of the prior art is so inefficient and expensive that it is extremely annoying, it is not possible to repair the defective part by means of a grinding wheel or the like.

  requires space for additional installations.

  and transportation work is complicated.

  On the other hand, with regard to the elimination of the surface defects mentioned above, it has been

  recently suggested that the defective part of the

  face is cut only over a predetermined length of its circumference, in order to

  is reduced by the general example of the prior art

  higher because the wire is either polluted whole length * around its circumference by means of a die or because it is cut by means of a tool

  cutter operating on the same principle as a lathe.

  Despite this proposal, the decrease in

  could not be avoided because the wire is * cut throughout its circumference, although

  only partially in the longitudinal direction.

  The Defaanderesse managed to realize the pre-

  invention by seriously repeating the experi-

  these and the researches while targeting as it was described above: a first target-consisting of

  replace the discontinuous process by a process of labeling

  continuous rage to eliminate performance problems, etc .; as a second target to achieve a "dry" type process which is advantageous because the wet process can not produce satisfactory working conditions, and raises the costs of the installations,

  so that it is not acceptable; and as third

  target me to perform the detection and

  repair of defects during stretching.

  Accordingly, it is an object of the present invention to provide a method and a machine for continuous drawing of dry type wire which provides satisfactory working conditions, while eliminating the problem of disposal of used liquids and boosting productivity to reduce cost by performing

  the wire drawing process continuously.

  Another object of the invention is to provide a method and a machine for the continuous drawing of dry type metal wires which makes it possible to perform

  at the same time as stretching, the detection operations

  repair and repair of defects.

  Another object of the present invention is to

  carry a method and a machine for continuous drawing of dry-running metal wires which allows

  to carry out a secondary drawing intended to improve

  the condition of the surface of the product. According to one of the features of the present invention, a dry type continuous metal wire drawing method comprises deoxidizing the surface of a wire to be drawn; covering the yarn thus deoxidized with a lubricant; to stretch the thread

  lying down with the lubricant in a die that is

  characterized in that the deoxidation step comprises a mechanical substep of mechanical deoxidation treatment execution; and in that the lubricant coating step comprises a sub-step of laying the deoxidized yarn with lime powder and a sub-step of coating the lime-covered yarn with a metal soap powder, these three main stages being executed dry and in

continued.

  According to another particularity of the invention,

  a method of continuous wire drawing of dry type

  takes a step of scrolling the

  to be stretched, which unwinds from a food carrier

  in an installation including a step of mechanical deoxidation of the moving wire; a step of coating the surface of said wire with a lubricating agent powder; a step of coating the coated wire with a sprayed lubricant; a step of drawing the coated wire with the lubricant in a drawing die, a step of detecting defects in the surface of the drawn wire; a step of locating the surface defect taking into account the speed of translation of the drawn wire and detecting the instant of the passage of this defect and eliminating said defect of

  Surface-located; and a step of re-locking

ler the stretched thread.

  The present invention also comprises a machine for the continuous drawing of a wire of the type

  which includes a feeding rack for

  the thread to be stretched; means of deoxidation

  mechanics to remove oxide from the surface

  said thread; means for surface treatment of

  method comprising a die for applying a spray lubricant to the surface of said wire under pressure; dry type lubricating treatment means prior to drawing; a die to stretch the thread

  which has been lubricated; a first detection

  to detect surface defects of the drawn wire; automatic repair means for removing the defective surface portion of said drawn wire; a control unit which in response to a signal of said

  first surface fault detector sends a message

  repairing the said self-repairing means

  matic; a second surface defect detector for detecting defects left on the surface of the repaired wire; a marker for marking the unrepaired defective portion of said wire in response to an instruction from the control unit which has received the signal from said second fault detector; and, means for winding the repaired wire, all components of said machine, except for said control unit, being arranged

serial.

  The invention also includes a dry type continuous metal wire drawing machine which includes a feed rack for feeding a wire to be drawn; mechanical deoxidation means for removing oxide from said wire; processing means comprising a die for applying

  under pressure a lubricant powder on the surface of-

  said thread; dry type lubricating treatment means prior to drawing; a first die for drawing the thread which has been lubricated;

  a first detector for detecting

  face of the stretched wire; means of automatic repair

  to remove the defective portion of the surface of said drawn wire; a control unit which in response to a signal of said surface defect detector

  sends a repair signal to said repair means

  automatic rationing; a second die for re-drawing the repaired wire and means for winding the repaired wire, all the components of

  said machine, with the exception of said

  mande being consecutively arranged in series.

  Another particularity of the present invention is also in a machine for stretching the yarns

  continuous metal of the dry type which includes a rake

  to link feed to cut the thread to be

  stretched; mechanical means of deoxidation to eliminate

  undermine the oxide of said wire; means of treatment

  carrying a die for pressurizing a lubricating powder agent to the surface of said wire; dry type lubrication means for drawing; a first die for drawing the thread which has been lubricated; a detector for detecting surface defects of the drawn wire; automatic repair means for removing defective portions of the surface of said drawn wire; a control unit which in response to a signal from said surface fault detector sends a repair signal to said automatic repair means; a second die for re-drawing the repaired wire; a second surge detector for detecting surface defects left on the repaired wire; a marker for marking the unrepaired defective portions of said wire in response to an instruction sent by said control unit in response to the signal of said second surface fault detector; and means for winding the repaired wire, all components of said machine, except

  of said control unit being arranged consecutively

in series.

  Other features and advantages of the

  come out of the description which follows in

  reference to the accompanying drawings, in which:

  FIG. 1 is a diagrammatic view representing

  both the arrangement of a machine to stretch the wires

  continuous metallics of the dry type conforming to

  the invention; Fig. 2 is a schematic cross-sectional view showing the structure of the different lubricant layers applied to the wire to be drawn in accordance with the present invention; Figure 3 is a view similar to Figure 1 but showing another embodiment of the present invention; FIGS. 4A and 4B are schematic views showing the structure of the installation downstream of the wire stretching stage and upstream of the rewinding step thereof, the first corresponds to an installation with only one step

  while the second corresponds to an inser-

  a plant comprising two drawing steps; Figure 5 is a schematic sectional view

  rep resenting a repaired wire destined to undergo a second

  rage; Figs. 6A and 6B are views similar to Figs. 4A and 4B but showing other embodiments of the present invention; FIGS. 7A and 7B, 8A and 8B, 9A and 9B and 1A and 1B are also views similar to FIGS. 4A and 4B respectively, but representing other

  embodiments of the present invention.

  Since the present invention includes a number of preferred embodiments,

  will start the description by the basic structure

  located upstream of the stretching step, then we will describe different steps downstream of this step

primary drawing.

  Referring first to FIG. 1, there is shown a wire 11 which is to be stretched which is held on a feed machine 22 of a machine for continuous wire stretching of the dry type 20 according to FIG. the present invention and which is then used to feed a drawing train This feed is carried out by guiding the front end of the wire 11, which has been formed during a previous step. The wire 11 thus unwound from the feeding rack 11 is guided so as to pass through a corrector or rectifier 24 with vertical and horizontal action (that is to say, of the VH type) and in a blasting or sanding station

  26 operating as a mechanical stripping device.

  In this blasting station 26, suitable particles

  are projected with a projection density such as oxide film and other impurities

  present on the surface of the wire It is detached.

  Then, the wire 11 is passed through a bath of surfacing lubricant 28, a bath of reinforcing lubricant 30 and a bath of drawing lubricant 32 which are arranged one behind the other, in the order indicated, and are equipped at their respective outlets with a die 34 to apply a lubricant

  surfacing, a die 36 for applying a lubricant

  These baths 28 to 32 are respectively filled with a powder of

  lime forming the surfacing lubricant, a lubricant

  reinforcing filler such as sodium stearate, and a drawing lubricant such as a mixture of stearate of

  sodium or calcium and slaked lime.

  Thread 11 goes into bath 28 after being

  cleared of its oxides, then is guided towards the

  In this passage, the wire 11 is covered with a layer of lime powder 1 l A (FIG. 2). Next, since the diameter of the hole of the die 34 has been calculated to being slightly larger than that of the wire 11, the layer of powder li A, which has just been applied, and the layer of lime powder which surrounds it are compressed between the wall of the hole and the surface of the wire 11, while this wire 11 passes through the hole of the application die 34, so that the lime powder 11 A is pressed against the surface of the wire 11 The lime powder 11 A serves as a surface for the lubricants 11 B and 11 C, as shown in Figure 2 and serves to enhance the properties of the reinforcing lubricant

  ll B and drawing ll C lubricant, which will be applied

  On the other hand, not only slaked lime but also quicklime can be used as a powder. However, slaked lime is preferable because the hydrophilic properties of quicklime often pose problems. the lime powder is not

less than 2 microns.

  Then, the thread 11 passes into the lubricant bath.

  During this passage, the reinforcing lubricant 1 1 B is pressed, in the same way as previously the lime powder l A, against the layer of lime powder l A which has already been applied. on wire 11 Sodium stearate is used as reinforcement lubricant 1 l B When the particle size of sodium stearate

  used is not greater than 2 microns, its density

  coating is reduced by the so-called tunnel effect "which results from the passage through the

  inconsistent powder, so that the lubricating effect

  cation becomes insufficient. As a result, it is preferable

  that the size of the sodium stearate should be

at least 2 microns.

  On the other hand, it is preferable to apply a reinforcing lubricant 11B, but this could be eliminated in the case of drawing a wire having a

low resistance.

  After that, the wire 11 is guided to the bath of drawing lubricant 32 This bath 32 is filled with a mixture of sodium stearate or calcium and lime constituting the lubricant 11 C, which is called to be

  pressed against the layer covering the surface of the wire 11.

  Next, wire 11 is subjected to a (primary) drawing treatment with a predetermined draw ratio, by

  the action of the drawing die 38.

  Referring now to Figure 2, we de-

  writes in more detail below the surfacing lubricant

  li, the reinforcing lubricant 11 B and the lubricant

  The surfacing lubricant li A consists of a slaked lime whose granulm sort is not less than 2 microns, octcre it was indicated above On the other hand, the lubricant reinforcement 11 B is chosen Among the so-called "metallic soaps" comprising calcium, sodium, zinc and aluminum stearate. In addition, the drawing lubricant Li C is constituted by a mixture comprising, on the one hand, a metallic soap based on sodium or calcium stearate, titanium oxide, borax, for example (Na 2 B 407, H 20 or Na B 407 5H 20) and slaked lime. stearate and the rest, that is titanium oxide, borax and slaked lime is usually between 50 and 80% by weight of the first and 20 to 50% of the second and can change the point On the other hand, the coating density is set to at least 5 g / m 2 for the surfacing lubricant. at least 1 g / m 2 for the reinforcing lubricant 1 1 B and at least 2 g / m 2 for the drawing lubricant 11 C, the total being at least log / M 2 embodiment described at this point, we have taken as examples, for the dies 34, 36 and 38, dies with holes, but it could also be

roller dies.

  The wire 1 which has been stretched is guided to a defect detector 40 which may be an eddy current type flaw detector, as shown in FIG. 1. The wire 11 'may not only have intrinsic material defects. but also handling and / or stretching defects that were caused by seizures or the like during its passage through the drawing die 38.

  defects of any kind are continuously detected in

  in the detector 40, so that the defective part

  killer may be eliminated in a device 42 in

  response to a signal emitted by the detector 40.

  The thread ', which has thus undergone a series of

  The wire 1 is then transferred to undergo a secondary drawing operation. However, the wire 11 'could also be shipped without undergoing further processing, as

  cold-forged metal wire, when it is

  peeled to be used in applications in the

  what strict quality requirements do not apply with regard to surface condition, etc.

  In the preceding embodiment, it is

  read the blasting station 26 as a mechanical device

  to remove surface layers of oxide.

  On the other hand, as shown in FIG.

  blasting 26 could be replaced by a cam-

  roller or roller 24 'The camber 24' has

  function of bending and straightening

  punched the wire 1 l 'in order to crack and take off

  the oxide layer, while straightening it.

  Length of the camber 24 'is judiciously chosen Incidentally, it is quite natural to use

  the roller camber 24 'and the gravel device

  lage 26 together for mechanical deoxidation.

  We now describe in detail one of the

  main features of the present invention,

  The device of the present invention is of the "dry" type and performs the continuous stretching treatment, which differs from the conventional batch processing system which is inefficient and cotteuse, in fact the drawing system. Continuous embodiment according to the present invention allows a translation speed of up to about

  m / min, for example, which corresponds to an improvement

  outstanding performance of the treatment.

  On the other hand, when the fault detector 40 and the fault eliminator 42 are disposed along the continuous line of treatment of the wire, treatments

  can be achieved, unlike the system

  discontinuous system of the prior art where detection and correction of defects

problems.

  The present invention adopts the "dry" system

  in the case of a stretch-continuous treatment of the wire.

  It is known in the prior art to provide a dry type drawing lubricant upstream of the drawing die so that the wire can be stretched after being covered with this lubricant.

  however, it was not known before the present invention.

  that the treatment with the surfacing lubricant and, if necessary, the treatment with the reinforcing lubricant are carried out dry. In contrast, according to the present invention, a lime powder is used.

  As a surfacing lubricant in the prior art,

  zinc phosphate, which is an excellent

  expensive, but expensive, is used as a surface lubricant However, phosphate

  zinc can not be applied in the present

  which uses dry treatment,

  Because of this, it is a liquid.

  Reads a lime powder instead of the zinc phosphate. The drawn wire, which has been prepared by a surfacing treatment with the lubricating powder

  lime and by dry type lubrication, is not always

  days, in terms of its state of over-

  face, to a stretched wire that has been prepared by a lubricant

  "wet" type which is driven by a

  Representative of the prior art com r taking a pickling step, followed by a surfacing step with zinc phosphate, itself followed by a lubrication step with the mixture of lime

  In spite of this fact, the treatment of

  primary drawing is a preliminary treatment.

  preceding a secondary stretching treatment

  and the state of the wire surface can be improved

  sibly by the secondary processing step In

  Consequently, the simplified method, in accordance with

  invention, may be sufficient to achieve the objectives

  above and is relatively rational.

  One of the main advantages that can be

  obtained with this dry system lies in the possibility of

  to shorten the length of the installation and thus reduce the cost of the installation.

  for example, if we want to

  continuously with the "wet" system, the treatment

  surface with lubricant and treatment

  lubrication require a considerable reaction time

  to develop a film having a predetermined thickness, so that a long installation is essential On the other hand, with the "dry" system

  obtain the advantages mentioned above because it requires

  at most, baths of small dimensions,

  with the corresponding channels In addition, the conditions

  In general terms, neither the sodium stearate nor the mixture of lime and calcium stearate is dissolved as in the prior art before being used for wet treatment. On the contrary, in the dry system the materials specified above can be used, as is, so that one

  gets handling conditions.

  As described above, the method of the present invention enables the drawing operations to be carried out in a remarkably economical manner, in part because these operations are carried out dry and continuously and partly because the Surface treatment is carried out with a lubricant which is in the form of inexpensive lime powder. Accordingly, the process of the present invention has the advantage that surfacing and reinforcing lubricants have excellent sleeping because they are

  compressed and applied by pressure through the dies.

  The present invention is now described in

look at the examples that follow.

Example 1

  The drawing operation is carried out using an installation having a structure similar to that of FIG. 1. The yarn used is a 545 C mild rolled steel wire having a diameter of 14 mm. This wire was stretched under the following conditions: (a) Deoxidation step

  Deoxidation was carried out by a grenail-

  with the steel balls having an average diameter of 0.3 mm and with a shot peening density of about 300 kg / m (b) Lubrication conditions The operation of surfacing with a lubricant was carried out using a powder of lime having an average particle size of 15 microns The reinforcement lubrication was carried out using sodium stearate

  having an average particle size of 12.5 microns. The lubricant

2528734 before stretching was carried out using

  a mixture of lime and calcium stearate.

  (c) Stretching conditions A stretched wire having a diameter of 11.6 mm was prepared at a translational or traveling speed of 41 m / min and operated with a reduction of 26.2% using a spinneret. drawing having a

angle of 2 a = 200.

  (d) Failure detection conditions-

  The defects were detected at a phase angle of

  1300 and at a frequency of 64 kHz using a

  current-type rotary probe fault tester

of Foucault.

  The comparison between the stretching system of the

  present invention and a reference where only one

  pre-stretching has been carried out, shown in Table 1 In this table, the length of the die indicates elongation of the wire until the die seizes, and is a measure of the quality of the wire. stretched because the absence of galling indicates the excellent lubrication of the wire.

TABLE 1

  Lubrication of Duration of the die conditions Ref 1 Only C 1,000 3,000 kg Test 1 A + B 30,000 45,000 kg Test 2 A + B + C 50,000 70,000 kg

  o A denotes the lubricating surfacing treatment

  fication (with lime) B: indicates reinforcement lubrication treatment (with sodium stearate) C: indicates drawing lubrication treatment. Examination of Table 1 above leads to the conclusion that a high quality drawn yarn can be produced in accordance with the present invention.

* Example 2

  The drawing operation is performed using a

  similar to Figure 3

  Positive bending used included five rollers or rollers with a diameter of 90 mm arranged vertically

  and horizontally The elongation of the thread in this cam-

  the other hand, the drawing die

  used was a roller or roller type.

  States are shown in Table 2 below.

TABLE 2

  Lubrication of Duration of the die conditions Ref 2 Only C 1 500 3 000 kg Test 3 A + B 40 000 60 000 kg Test 4 A + B + C 55 000 70 000 kg o A, B and C have the same meaning as in the

table 1.

  Considering the results above, we find that

  the duration of the sector has been improved, compared

  This improvement is due to the counter-tension produced by the bending operation. More precisely, by this operation, a tension oriented opposite the direction of translation has been exerted. on the wire 11 As a result, the pressure exerted on the surface of the die 38 has been reduced, which has

  translated by an increase in its duration.

Example 3

  The structure of the installation is similar to that of Example 2, but the elongation of the yarn by the camber 24 'was 32% and the drawing and deoxidation steps were conducted simultaneously. In the operation, a yarn having a diameter of 14 mm was stretched to a diameter of 12.2 mm by a reduction in its area of 24%. Then, during a second stretching step using a spinneret. hole, the area of the wire was reduced again by about 10%, so that a wire with a diameter of 12.2 mm was obtained a stretched wire of 11.6 mm These úésulcats are presented in Table 3 and reveal that the duration of the die has been remarkably improved thanks to this new increase of the counter-tension.

TABLE 3

  Lubrication of Duration of the die conditions Ref 3 Only C 5,000 10 000 kg Test 5 A + B 70 000 90 000 kg Test 6 A + B + C 100 000 -120 000 kg o A, B and C have the same meaning as in the

Tables 1 and 2.

  On the other hand, the wire thus stretched not only has its intrinsic defects, but also handling and / or drawing defects caused by seizing or otherwise, when passing through the drawing die. material,

  internal faults can not be corrected.

  In addition, some surface defects can not be corrected or repaired, and are not suitable for

handling.

  The drawn yarn was processed in an identical installation by operating as follows, in accordance with the

present invention.

  Figure 4 A represents another embodiment of

  According to the present invention, a speedometer 46 is provided for measuring the speed of translation of the wire 11 'which has been stretched. The signal of the speedometer 46 is applied to a control unit 48 so that it can be used for adjustment of the speed by means of a reel which will be described later Downstream of the speedometer 46 is disposed a surface fault detector 50 which is of the eddy current type or other The signal of this surface defect detector 50 is also

  applied to the control unit 48, so that a repair

  Automatic controller 52 disposed downstream of detector 50 can intervene to eliminate the defective part of the surface in accordance with the instruction of the control unit 48 The wire thus repaired is wound on the reel 54 Then the wire 11 'thus wound is transferred to undergo a secondary drawing operation, as will be described with respect to FIG. 4B As shown in FIG. 4B, the repaired wire 11 'is subjected to a secondary drawing treatment intended to improve its state of surface by means of a secondary drawing die 56 before being wound on the reel 54 Alternatively, the wire 11 'which has been stretched once can be delivered, as it is, when it is intended for use which does not require

  not a very high surface quality.

  Here, the counter 46 measures the speed of travel or translation of the wire 11 'which has undergone primary stretching The position adopted for the speedometer 46 can, in principle, as shown in FIGS. 4A and 4B, be located downstream of the drawing die 38 (shown in FIGS. 1 and 3) or downstream of the surface defect detector 50 Alternatively, the speed of translation of the wire 11 'can be measured based on the number of revolutions per minute The speed of translation of the wire can be chosen arbitrarily, but must be between 60 and 80 m / min for a wire having a diameter of 20 rqm, or between 10 and 15 m / min for a wire. whose

  the diameter is between 20 and 25 mm, for example.

  The surface defect detector 50 could, for example, be an ultrasound device, but it is preferable to use an eddy current detector because of its detection power and its stability. locates the fault, detects the circumferential angular position and the longitudinal position thereof and, in addition,

  measure the depth at which it is located.

  of the defect is judged by the control unit 48 based on the signal from the

speedometer 46.

  The detected surface defect is

  automatically repaired by the automatic repairer 52 in response to an instruction from the control unit 48 In the automatic repairer 52, a suitable tool, such as a grinding stone, a sander or a tool for cutting, peeling or shaving, or, preferably, an internal abrasive stone 52, as shown, rotates around the drawn wire 111 so as to be rapidly applied against the surface of said wire 11 ', as soon as the defective part of its surface reaches the position of the abrasive stone 52 In the case where the repair tool is circumferentially offset from the defect position of the

2528734

  wire surface, the repair operation starts

  after the tool has been rotated to the desired position.

  If necessary, several repair tools could be arranged around the stretched wire 11 'In addition, the range of repairs could be chosen slightly larger than the length, the depth and the width of the surface defect considered. However, from the point of view of performance, it is appropriate that the repair is not carried out over the whole length and over the whole turn, but only, in the circumferential direction,

  on the defective part of the surface.

  In this operation, it should be considered the case in which the repairer 52 can not follow the speed of translation of the wire 11 'In this case, when a surface defect is detected, the reel 54 slows or stops on a speed control circuit command of the motor fitted to the winder 54, in response to an instruction from the control unit 48, at the instant when the defective part reaches the repairer 52, so that the translation of the wire can be slowed or interrupted to facilitate repair After this repair, the speed of translation of the wire

returns to its previous value.

  Referring now to FIG. 5, it should be noted that since on the surface of the wire 11 'a portion a has been removed which extends to a depth of about 0.1 to 0.5 mm it remains on the surface a scratch ll'a which, if not treated, is not satisfactory, given the application for which the product is intended To eliminate this repair scratch 11 'a, so that the wire has a diameter This secondary stretching die 56 has a structure similar to that of the primary die 38 and may be uniformly shaped around its circumference and subjected to secondary drawing by means of a secondary drawing die 56. Hole or roller type Prior to this secondary drawing step, the wire 11 'could be subjected, if necessary, to a treatment with a lubricant This secondary drawing die 56

  is arranged downstream of the automatic repairer 52.

  In the case where the internal defects must be

  detected and marked, as in the modes of

  As described later in the present invention, or in the case where the surface defects detected by the detector 50 which can not be automatically repaired should be marked, it is necessary that the secondary drawing die 56 be placed before the marking step, that is to say, it is arranged upstream of the marker indicating internal defects or unrepaired defects. The reason is that there is a risk that the mark will be erased by the stretching operation, in the event that the marking is carried out

before this operation.

  Figure 6 A shows another way of

  In the case where the present invention

  defective part of the surface detected by the detection

  50 is greater than about 0.2 mm or the number of defects present in the same

  part exceeds the possibilities or capacity of the repair

  52, these defects are either repaired as deeply as possible or are left unrepaired and are marked by the marker 58 in response to an instruction from the control unit 48. The defects that are not repaired are outside of

  the installation, beyond which wire 11 'has been wound.

  In this case, it is advantageous for the unrepaired defect marker 58 to rotate around the stretched wire 11 'so as to cover its entire circumference. Alternatively, a number of independent markers are circumferentially arranged, so that the defect (s) can be marked by the marker (s) occupying the corresponding positions The marking operation can be executed in such a way that one can

  distinguish the nature of the defects by different colors

  or the importance of the marks, depending on the

their depth or their nature.

  In the modification shown in FIG. 6B, the secondary drawing die 56 is interposed between the automatic repairer 52 and the

  marker of unrepaired defects 58.

  Now considering Figure 7A,

  sees another embodiment of the present invention.

  invention in which an immersed type ultrasonic flaw detector is arranged downstream of the automatic repairer 52, thereby to detect internal defects, which can not be repaired, so that the part with this internal flaw can be marked by a marker 62 arranged for this purpose downstream of the ultrasonic detector 60, which marker has a structure similar to that of the unrepaired defect marker 58 and which is actuated by an instruction of the control unit 48 The part containing the defect internally detected is discarded or unused after stretched wire

has been rolled up.

  Figure 7B shows the modification of the

  embodiment of Figure 7A In this modification

  fication, the secondary drawing die 56 is disposed downstream of the automatic repairer 52 and an ultrasonic flaw detector 60, of the submerged type,

  is disposed downstream of the secondary die 56.

  In the case of the modification above, the secondary die 56 could, alternatively, be interposed between the ultrasonic detector 60 and the

  marker 62, unlike the provision

  7B In this particular case, the defective part detected by the detector 60 can be stored by the control unit 48 and the elongation of the drawn wire by the secondary die 56 must be calculated so that the part of the surface of the wire 11 'which corresponds to the part detected above

can be marked.

  Figure 8 A shows another way of

  embodiment of the present invention, which differs from the installation of FIG. 7A, in that the unrepaired defects marker 58 is interposed between the

  automatic repairer 52 and the ultrasonic detector 60.

  FIG. 8B shows a modification of the embodiment of FIG. 8A where the non-repaired fault marker 58 is interposed between the secondary die 56 and the ultrasonic detector 60, unlike the installation of FIG. 7B As an alternative to the arrangements shown, the unrepaired defect marker 58 could be disposed downstream of the ultrasonic detector 60, while the secondary draw die 56 could be interposed between the auto repairer 52 and the ultrasonic defect detector 60 The elongation of the wire 11 'must be taken into consideration during the marking operation by the marker 58 in the first case and during the marking operations by the unrepaired defect marker 58 and the defect marker

internal 62 in the second case.

  FIG. 9A shows another embodiment of the present invention in which a second surface flaw detector 50 'is disposed downstream of the automatic repairer 52, so as to be able to detect if there is not a part of the surface that has been left unrepaired by the auto repairer 52 If this were to be the case, the part left unrepaired is indicated by the non-repaired defect marker.

repaired 58.

  Figure 9B shows a modification of

  embodiment of FIG. 9A or the second detection

  The surface defect unit 50 'is disposed downstream of the automatic repairer 52 and the secondary die 56, so that it can detect whether any defect has been forgotten by the automatic repairer 52 and so as to enable, in the case where such an unrepaired defect would be found, that it can be indicated by

  the unrepaired defect marker 58.

  Figure 1 OA shows another embodiment of the present invention, in which the ultrasonic flaw detector 60 and the internal flaw tag 62 have been added, downstream of the unrepaired flaw tag 58 to an installation.

  structure similar to that of the mode of

  FIG. 1B shows a modification where the secondary drawing operation is carried out as in the embodiment of FIG. 1A In the variant of FIG. 1BB, the ultrasonic flaw detector 60 and the internal fault marker 62 have been added, downstream of the unrepaired defect marker 58, to an installation having a structure

  similar to that of Figure 9 B as in Figure 10A.

  In the modifications of the embodiments of FIGS. 9A and 10A, the secondary drawing die 56 could also be arranged in an arbitrary position, as in the other embodiments,

  when placed downstream of the automatic repairer

  tick 52 and upstream of the markers 58 and 62.

  The embodiments of FIGS. 10A and 10B are the most suitable, since they cover all the operating steps, but those of FIGS. 7A and 7B are the most practical, if one

  takes into consideration the cost of the facilities.

  In the embodiments described in

  this point, it is desirable that the different

  However, it is possible, for example, to detect surface defects after the internal faults have been detected or to change the position of the marker (s). It is also possible to detect internal defects and surface defects This can be achieved by

  example, by a process that uses discrimi-

  nation the shape or pace of the signals of a

ultrasonic detector.

  Thus, in accordance with the present invention, since fault detection and repair

  Automatic stretching of the wire is carried out without

  on-line, it is possible not only to reduce the number of repair steps, to save space for installation and to eliminate transport work, but also to high speed, so that a flawless wire can be delivered with a remarkably

effective.

  The present invention will now be described in more detail with regard to Examples 4 to 6 below, which relates to an installation comprising only one

primary drawing stage.

Example 4

  The drawing process is carried out using an installation having the structure similar to that of FIGS. 1 and 7A. The wire used is a standard rolled steel of 545 C mild steel having a diameter of 14 mm. following conditions (a) Deoxidation conditions Shot peening with steel balls having an average diameter of 0.3 mm was carried out

  with a shot peening density of about 300 kg / m 2.

  (b) Lubrication Conditions The operation of surfacing with a lubricant was carried out using lime powder

  having an average particle size of 15 microns The lubricant

  Reinforcement was carried out using sodium stearate having an average particle size of 12.5 microns. The lubrication preceding the drawing was carried out using a mixture of lime and

calcium stearate.

  (c) Stretching conditions A stretched wire having a diameter of 11.6 mm was prepared at a running speed of 41 m / min and a reduction of the area of 26.2% using a spinneret. drawing with an angle of 2 "= 20 and a span of 0.5 d (where the letter d denotes

the diameter of the die).

  (d) Fault Detection Conditions Surface defects were detected at a phase angle of 1300 and operating at a frequency of 64 kHz using a rotary probe type Fault Detector. In addition, internal faults were detected by operating at a frequency of 20 M Hz and using a

ultrasound of the immersed type.

  (e) Automatic Gold Repair Terms

  Automatic repairs were carried out

  killed by dividing the circumference of the wire into thirty-six sections and repairing only the local section in which the surface defect is detected, with the inner wall of a rotating abrasive stone having

a cylindrical shape.

  A comparison between the drawing system of the present invention and a reference to the

  prior art o only a pre-lubrication

  In this table, the duration of the die corresponds to the elongation of the wire until a seizure of the die occurs, and this duration is a measure to evaluate the yielding. the quality of the thread stretched because the absence of galling corresponds to an excellent

lubrication of the wire.

TABLE 4

  Lubrication of Conditions Prior Art Invention Invention Only C A + B

A + B + C

Duration of the sector

1,000 -

2,000 kg

5,000 -

6.000 kg

10,000 -

  12.000 kg Power of detection of faults

(1) (2)

  / 100m 0.2mm / 100mm 0.2mm o: (1) indicates the lower limit of depth of detectable surface defects; and,

  (2) indicates the detectable internal defects.

  o: A, B and C have the same meaning as in the

table 1.

  Incidentally, the results for research on the sodium stearate coating density as a function of average particle size are shown in Table 5. Sodium stearate particles having an average diameter of less than 2 microns were affected by what is the "tunnel effect", so that they were unable to coat the wire with a satisfactory density,

  thus not fulfilling the practical objective.

TABLE 5

  Average Particle Diameter Coating Density 2 to 3 microns 0.8 g / m 2 to 7 microns 4.1 g / m 2 Based on Table 4 above, the conclusion is that a high quality drawn wire can be

  produced in accordance with the present invention.

Example 5

  The drawing operation is carried out using an installation having a structure similar to that of FIGS. 2 and 7A. The bending unit used comprised five rollers or rollers having a diameter of mm arranged vertically and horizontally. The degree of elongation of the yarn by this camber was% On the other hand, the drawing die used was pebble type The results are shown

in Table 6 below.

TABLE 6

  Lubrication conditions Hole die Time dies with roller die power of (1) fault detection (2)

rech anter.

  Invention 1 only C A + C 1 500 3 000 kg 7 500 9 000 kg 000 000 kg 000 000 kg Invention 2

A + B + C

000 000 kg 000 000 kg

  o A, B and C have the same meaning as in Table 1.

  r%) "J co - 4/100 mm 0.2 mm / 100 mm 0.2 mm% O The results above show that the length of the die has been prolonged, compared to the blasting system of the example 4 This improvement was acquired thanks to the counter-tension developed by the operation of bending or bending More precisely, by this action a tension in the opposite direction

  to the translation direction has been applied to wire 11.

  As a result, the surface pressure exerted on the die was reduced, which resulted in

  lengthening of its useful life.

Example 6

  The installation used is similar to that of Example 5, but the elongation of the wire by the roller camber is 32% and the drawing step is carried out at the same time as the step of eliminating Surface oxides In operation, a wire having a diameter of 14 mm was stretched to 12.2 mm by a reduction in area or section of 24%. As a result, in a second drawing step, using a hole die (identical to that of Example 4) the yarn area was reduced by about 10%, i.e., a yarn having a diameter of 11 was obtained, 6 mm The results of this test are presented in Table 7 and reveal

  the duration of the sector has been remarkably improved

  thanks to a further increase in the counter-

pressure. -

  Conditions de 1 Duration 1 power of decay

1 1 defects

  ltbrificatior die of defects (1) j (2)

only 10000 -

1A 5 o 20 000 kg

Inven 50,000 -

  1 5/100 mm 0.2 mm tion + 1 day 60 300 kg

inven A + B + 100,000 -

  Ition 2 + C 120 000 kg / 100 mm 0.2 mm

31 2528734

  We will now proceed to a description

  Detailed description of the present invention with reference to Example 7 below which relates to an installation comprising both a primary and secondary stretching step

Example 7

  The drawing operation is carried out using an installation having a structure similar to that of FIGS. 1 and 6 B. The wire used is a 545 C mild steel standard rolled wire having a diameter of 16 mm. This wire has been drawn into the following conditions (a) Deoxidation conditions Shot peening was carried out with steel balls having an average diameter of 0.3 mm operating at a shot peening density of approximately

300 kg / m 2.

  (b) The lubricant surfacing operation was carried out using a lime powder having an average particle size of 15 microns. The reinforcing lubrication was performed using sodium stearate having an average particle size of 12.5 microns. Lubrication before stretching was carried out with a mixture of lime and stearate

of calcium.

  (c) Stretch conditions Stretched wire having a diameter of 13.5 mm was produced at a translation speed of 41 m / min and operating with a reduction of the section or

  area of 28.9% using

  mayors and secondaries with an angle of 2 a = 200 and a span of 0.5 d (where d is the common diameter of the two dies). In addition, the distribution of the area primary and secondary materials was fixed at 16 mm to 15 mm (ie at a 12% reduction percentage) and 15 mm at 13.5 mm (ie at a percentage reduction of 19%), in diameter. (d) Fault Detection Conditions Surface defects were detected at a phase angle of 1300 and at a frequency of 64 kHz using a rotary probe type eddy current fault detector. internal defects were detected at a frequency of 20 M Hz using an ultrasonic detector of

submerged type.

  (e) Automatic Repair Conditions

  Automatic repairs were carried out

  killed by dividing the circumference of the wire into thirty-six sections and automatically repairing only the local section in which the surface defect exists, using the inner wall of a stone

  abrasive abrasive having a cylindrical shape. A comparison between the drawing system of the present invention and a

reference of the

  prior art in which only a lubricant

  before drawing is carried out, is pre-

  Table 8 In this table, the length of the die indicates the elongation of the wire until die seizure occurs and is a measure of the quality of the drawn wire because

  the absence of seizure indicates an excellent lubricant

fication of the wire.

TABLE 8

  conditions of duration power of detec 1 lubrication die tion of faults

1 (1) 1 (2)

  Inven AA + C 5/100 mm 0.2 mm _ 30,000 kg

A + B + C

, 000 -

, 000 kg / 100 mm 0, 2 mm o A, B,

board

  C have the same meaning as in 1. In view of Table 8 above, the conmusion is that a high quality drawn wire can be

  produced in accordance with the present invention.

  In addition, research results

  the effect of eliminating scratches due to repairs

  rations by the secondary drawing stage are indicated

in Table 9 below.

TABLE 9

  o (3) indicates depth of repair (a) of defects (4) indicates reduction of area or section

by 1 secondary stretching.

  It is clear from Table 9 above that the second drawing operation sufficiently remedies the scratches resulting from the repairs and that scratches * .g

inventors

  2 to a depth of up to 0.5 mm could be completely eliminated when the reduction of the section in the drawing operation

secondary education exceeds 19%.

  Thanks to the secondary stretching operation, the reduction of the area or section in each drawing die could be reduced sufficiently for

  that the duration of it is remarkably prolonged.

  At the same time, the skin condition of the stretched wire could be remarkably improved, compared to the system

  comprising a primary stretching operation

  the distribution of the reduction of the section or area between the primary and secondary drawing operations must be carefully chosen in accordance with the material used, while taking into account the thinning of the finished wire (which is due to to the influence of the reduction of the section or area of the primary drawing operation acting as a counter-tension

  on the secondary stretching operation).

Claims (28)

  A method for drawing a continuous dry type wire which comprises: (1) a step of removing the wire to be drawn from its oxide layer, (2) the step of covering the deoxidized wire a lubricant, and (3) the step of stretching the coated wire with the lubricant in a die, characterized in that the deoxidation step (1) comprises a mechanical sub-step of performing the treatment of mechanical deoxidation, and in that the coating step (2) with the lubricant comprises a substep of covering the deoxidized yarn with a lime powder, and a substep of covering the lime-covered yarn of a metallic soap powder, all the steps (1) to   (3) being carried out dry and continuously.   2 stretching method according to claim 1, characterized in that the mechanical step of deoxidation (1) further comprises a substep of & shot blasting   of the surface of the wire to be stretched.   3 stretching method according to claim 1, characterized in that the mechanical step of deoxidation (1) comprises a substep of bending, bending   or folding the wire to be stretched.   A drawing method according to claim 1, characterized in that said lime powder has a   mean particle size equal to or less than 50 microns.   A drawing method according to claim 1, characterized in that the sub-step of applying the lime powder is carried out by passing the yarn to be drawn into a bath containing lime. 36 2528734   6 stretching method according to claim 5, characterized in that performs the sub-step of applying the lime powder by means of a die mounted at the outlet of said bath to allow the wire to circulate and which has an inside diameter 0.1 to 0.2 mm greater than the diameter of the wire to be stretched, so that the sub-step of applying lime can be ensured by passing said wire in said coating die.   7 stretching method according to claim 1, characterized in that the density of the layer of lime applied to the surface of the wire to be stretched is equal to or greater than 5 g / m 2.   8 stretching method according to claim 1,   characterized in that the sub-step of applying   cation of the metallic soap by passing the wire carrying the layer of lime into a bath containing a metallic soap.   Stretching method according to claim 8,   characterized in that the sub-step of applying   cation of the metallic soap and the wire drawing sub-step in a single step by mounting said drawing die in the outlet of a bath containing a metal soap to allow it to pass therethrough.   and being drawn into said drawing die.   A drawing method according to claim 1, characterized in that the density of the metal soap coating on the surface of the wire to be stretched is equal to or greater than 2 g / m. 11 A drawing method according to claim 1, characterized in that that the lubricant application step (2) further comprises a substep of applying to the wire carrying the lime layer a sodium stearate powder before the substep application of metallic soap.   12 stretching method according to claim 11, characterized in that the sodium stearate powder has an average particle size equal to or greater than 2 microns.   Stretching method according to claim 11,   characterized in that the sub-step of applying   cation of the sodium stearate by passing the wire carrying the layer of lime into a bath containing sodium stearate.   14 stretching method according to claim 13, characterized in that executes the substep of application of sodium stearate by means of a   die mounted at the outlet of said bath so as to allow   to pass through it and which has an inner diameter 0.1 to 0.2 mm greater than that of the wire carrying the lime layer, so that the sub-step of applying sodium stearate can be assured by passing the thread carrying the layer   lime in said coating die.   A drawing method according to claim 11, characterized in that the density of the sodium stearate layer on the surface of said lime-covered wire is equal to or greater than 2 g / m   16 Process for continuously drawing a metal wire   a dry type that includes: (1) a step in which the thread is passed in front of   to be stretched, which is rewound from a food rack   in an installation, (2) a step of metal deoxidation of the moving wire, (3) a step of coating the surface of said wire with a powder lubrication surfacing agent, (4) a wire coating step carrying the surfacing layer with a powdered lubricant, (5) a step of drawing the coated wire with the lubricant in a die, (6) a step of detecting defects present in the surface of the drawn wire, ( 7) a step of locating the surface defects as a function of the translation speed of the stretched wire and the time of detection of the surface defect, and to eliminate the surface defect thus localized, and   (8) a step of rewinding the drawn wire.   Drawing method according to claim 16, characterized in that it also comprises:   (9) a step of marking surface defects detected   during step (6), who can not be eliminated in step (7).   A drawing method according to claim 16, characterized in that it further comprises: (10) a step of detecting internal defects of the son stretched by ultrasound, and   (11) a step of marking the internal defects detected.   The drawing method as claimed in claim 16, characterized in that it also comprises: (12) a step of adjusting the winding speed in accordance with an internal fault detection signal of said step (16), so as to to ensure   eliminating the fault in said step (7).   A drawing method according to claim 16, characterized in that it further comprises (13) a step of again detecting the presence of a surface defect after said step (7) and marking the defective portion thus detected.   Stretching method according to claim 16,   characterized in that the elimination operation is carried out   ground surface defects of said step (7) by passing said drawn wire through the central hole of an annular abrasive stone so that said wire can be brought into contact with the inner wall   of said stone and can thus undergo abrasion.   Machine for continuous wire stretching of the dry type which comprises: a feed rack (22) for unwinding the wire (11) to be stretched, mechanical deoxidation means for removing the oxide layer from the surface of said thread   surfacing treatment means comprising   both a die to apply under pressure an agent   lubricating surfacing surface (28) to the overlying   facing said yarn, dry type lubricating treatment means prior to drawing, a drawing die (38) for drawing the yarn which has been lubricated, a surface defect detector (40) for detecting defects of the drawn wire, automatic repair means (42) for removing the defective surface portions of said drawn wire, a control unit which in response to a signal of said surface fault detector sends a repair signal to said repair means automatic, and winding means (44) for winding the repaired wire, all components of said machine, except for said control unit, being   arranged consecutively in series.   A stretching machine according to claim 22, characterized in that it further comprises: a marker for marking detected surface defects which can not be automatically repaired in response to an instruction from said control unit. A stretching machine according to claim 22, characterized in that it further comprises: an ultrasonic flaw detector for detecting the presence of an internal defect in the repaired yarn, and a marker for marking the surface of said yarn which corresponds to the part having an internal fault, in response to an instruction from said control unit responding to the signal triggered by a fault   internal of said ultrasonic detector.   Stretching machine according to claim   cation 24, characterized in that it further comprises means comprising a die for applying   under pressure a reinforcing lubricant on said lubricant   surfacing machine, and a speedometer for measuring the translation speed of said wire, said winding means being at variable speed and being able to be slowed during the repair of a defect in response to the signal said speedometer.   26 Machine to continuously stretch a metal wire-   dry type machine which comprises: a feed rack for feeding a wire to be stretched, mechanical means for removing the oxide layer of said wire, processing means comprising a die for applying under pressure a surfacing agent powder lubrication on the surface of said wire, dry type lubricating treatment means preceding the die, a drawing die for drawing the thread which has been lubricated, a first surface defect detector for detecting defects of the stretched wire surface, automatic repair means for removing the defective portion of the surface of said drawn wire, a control unit which in response to a signal of said first surface fault detector sends a repair signal to said automatic repair means a second detector for detecting surface defects left in the repaired wire,   a marker to mark the defective parts   its unrepaired of said thread in response to an instruction   issued by the control unit following receipt of   signaling the second surface fault detector, and means for winding the repaired wire, all the components of said machine, except for the control unit, being arranged uniformly serial.   Machine according to claim 26, characterized   in that it further comprises an ultrasonic detector for detecting the presence of an internal defect in the repaired wire, and a marker for marking the surface of said wire which corresponds to the defective inner part, in response to an instruction issued by said control unit in response to a signal indicating a defect   internal of said ultrasonic detector.   Dry type continuous wire stretching machine which comprises a feed rack for feeding the wire to be drawn, mechanical deoxidation means for removing the oxide layer of said wire, processing means comprising a die for applying pressurizing a powder lubrication surfacing agent on the surface of said wire, dry type lubrication treating means prior to the die, a first drawing die for drawing the wire which has been lubricated, a sensor for detecting the surface defects of the drawn wire, automatic repair means for removing the defective portion of the surface of said drawn wire, a control unit which in response to a signal of said surface fault detector sends a repair signal to said means of automatic repairs, a second die for re-drawing the wire repaired, and means for winding the wire trimmed, all components of said machine, except for the control unit being arranged consecutively serial.   Machine according to claim 28, characterized   in that it further comprises a marker for marking unrepaired faults of said wire in response to an instruction issued by the control unit in response to the signal of the second defect detector of surface.   Machine according to claim 28, characterized   it also includes an ultrasonic detector for detecting the presence of an internal defect in the repaired wire, and a marker for marking the surface of said wire which corresponds to the portion having an internal defect, in response to an instruction transmitted by said control unit in response to the signal of said internal ultrasonic flaw detector.   Machine according to claim 30, characterized   characterized in that it further comprises: processing means comprising a die for pressurizing a reinforcing lubricant to said surfacing lubricant, and a speedometer for measuring the speed of said wire, the speed of said means for winding being variable, so that they can be slowed down during the repair of a defect in response to the signal of said speedometer.   32 Machine for stretching a wire in   continuous dry type that includes a food rack   a method for debiting the wire to be drawn, mechanical deoxidation means for removing the oxide layer from said wire,   surfacing treatment means comprising   a die for pressurizing a powder lubrication surfacing agent to the surface of said wire, dry type lubricating treatment means preceding the die, a first die for drawing the wire which has been subjected to the lubrication treatment, a detector to detect the defects of stretched wire surface ,.   automatic repair means for removing the defective portion of the surface of said drawn wire, * 44 2528734   a control unit which in response to a signal from said surface fault detector sends a repair signal to said automatic repair means, a second die to further stretch the repaired wire, a second surface fault detector to detect defects left behind on the surface of the repaired wire, a marker for marking the unrepaired defective portion of said wire in response to an instruction issued by the control unit in response to the signal of the second surface fault detector, and means for winding the repaired wire , all the components of said machine, except for the control unit being arranged consecutively serial.   Machine according to claim 32, characterized   in that it further comprises a marker for marking the surface of said wire which corresponds to the portion having an internal defect in response to an instruction issued by said control unit in response to the signal from said defect detector ultrasound.