Classifications

• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
  • C23C2/14—Removing excess of molten coatings; Controlling or regulating the coating thickness
  • C23C2/24—Removing excess of molten coatings; Controlling or regulating the coating thickness using magnetic or electric fields
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
  • C23C2/003—Apparatus
  • C23C2/0036—Crucibles
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
  • C23C2/003—Apparatus
  • C23C2/0036—Crucibles
  • C23C2/00361—Crucibles characterised by structures including means for immersing or extracting the substrate through confining wall area
  • C23C2/00362—Details related to seals, e.g. magnetic means
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
  • C23C2/34—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the shape of the material to be treated
  • C23C2/36—Elongated material
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
  • C23C2/50—Controlling or regulating the coating processes
  • C23C2/51—Computer-controlled implementation
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
  • C23C2/50—Controlling or regulating the coating processes
  • C23C2/52—Controlling or regulating the coating processes with means for measuring or sensing
  • C23C2/524—Position of the substrate

Definitions

• the invention relates to a device for hot-dip coating a metal strand, in particular a steel strip, in which the metal strand is guided vertically through a container holding the molten coating metal and through an upstream guide duct, with at least two inductors arranged on both sides of the metal strand in the region of the guide duct for generation an electromagnetic field for retaining the coating metal in the container and with at least one sensor for determining the position of the metal strand in the region of the guide channel.
• the invention further relates to a method for hot-dip coating a metal strand.
• the strips are introduced into the dip coating bath from above in an immersion nozzle. Because the coating metal in liquid Form is present and you want to use gravitation together with blow-off devices to adjust the coating thickness, but the subsequent processes prohibit contact with the strip until the coating metal has completely solidified, the strip must be deflected in the vertical direction in the coating vessel. This happens with a roller that runs in the liquid metal. Due to the liquid coating metal, this role is subject to heavy wear and is the cause of downtimes and thus failures in production.
• the position of the continuous ferromagnetic steel strip through the guide channel between two traveling field inductors is an unstable equilibrium. Only in the middle of the guide channel is the sum of the magnetic attraction forces acting on the tape zero. As soon as the steel strip is deflected from its central position, it comes closer to one of the two inductors while it moves away from the other inductor. Such deflection can be caused by simple belt flatness errors. Any type of band waves in the running direction, seen across the width of the band (centerbuckles, quarterbuckles, edge waves, fluttering, twisting, crossbow, S-shape, etc.) should be mentioned. According to an exponential function, the magnetic induction, which is responsible for the magnetic attraction, decreases in its field strength with the distance from the inductor.
• the attraction decreases with the square of the induction field strength with increasing distance from the inductor.
• DE 195 35 854 A1 and DE 100 14 867 A1 provide information on solving this problem, that is to say on the exact position control of the metal strand in the guide channel. According to the concepts disclosed there, it is provided that in addition to the coils for generating the electromagnetic traveling field, additional auxiliary coils are provided which are connected to a control system. stand and ensure that the metal strip is returned to the middle layer when it deviates from it.
• sensors are disclosed in WO 01/11101 A1, JP 10298727 and JP 10046310, without their specific structure and specific arrangement being specified there.
• the invention is therefore based on the object of specifying, for a generic device, a sensor for determining the position of the metal strand in the guide channel, which is distinguished by a high measurement accuracy, a simple structure and an inexpensive production possibility.
• the aim is to increase the efficiency of the regulation of the metal strand in the central plane of the guide channel.
• the solution to this problem by the invention is characterized in that the sensor for determining the position of the metal strand consists of two coils which - as seen in the conveying direction of the metal strand - are arranged within the vertical extent of the inductors and between the inductors and the metal strand.
• the coils and the inductors are arranged symmetrically with respect to the center plane of the guide channel.
• the coils are preferably the same and are designed as a wire winding without a core. They can have one or more turns. It is advantageously provided that the wire of the coils consists of copper. Furthermore, the turns of the coils can have a round, an oval or a rectangular shape.
• the coils are connected to a measuring device for measuring the voltage induced in the coils.
• the measuring device is designed for high-resistance measurement of the voltages induced in the coils.
• the measuring device can have a difference former, with which the difference between the two voltages induced in the coils can be determined.
• the metal strand is passed vertically through the container holding the coating metal and through the upstream guide channel.
• at least two inductors positioned on both sides of the metal strand in the region of the guide channel are arranged, the position of the metal strand in the region of the guide channel being determined by means of at least one sensor.
• the method according to the invention provides that to determine the position of the metal strand, two coils are provided, which, viewed in the direction of conveyance of the metal strand, are arranged within the vertical extent of the inductors between the inductors and the metal strand, the voltages induced in the coils being measured, the measured voltages subtracted from each other and the resulting value is used to derive an indicator for the position of the metal strand. After measuring the two induction voltages, a difference between the two values is carried out. Depending on the difference determined, the extent of the deviation of the metal strand from the central position is inferred.
• the proposed sensor for determining the position of the metal strand in the guide channel is characterized by a simple and therefore inexpensive Construction from. It also enables the position of the strand to be recorded very precisely.
• FIG. 2 shows a perspective view of an inductor with a measuring coil arranged in front of it.
• the hot-dip coating device has a container 3 which is filled with molten coating metal 2.
• molten coating metal 2 can be zinc or aluminum, for example.
• the metal strand 1 to be coated in the form of a steel strip passes the container 3 vertically upwards in the conveying direction R. It should be noted at this point that it is fundamentally also possible for the metal strand 1 to pass the container 3 from top to bottom. For the passage of the metal strand 1 through the container 3, it is open in the bottom area; here is an exaggeratedly large or wide guide channel 4.
• the inductors 5 are two alternating field or traveling field inductors arranged opposite one another, which operate in the frequency range from 2 Hz to 10 kHz are operated and build up a transverse electromagnetic field perpendicular to the conveying direction R.
• the preferred frequency range for single-phase systems (AC field inductors) is between 2 kHz and 10 kHz, that for multi-phase systems (e.g. traveling field inductors) between 2 Hz and 2 kHz.
• the aim is to hold the metal strand 1 located in the guide channel 4 in such a way that it is as defined as possible in a position, preferably in the center plane 7 of the guide channel 4.
• the metal strand 1 located between the two opposing inductors 5 is generally attracted to the closer inductor when an electromagnetic field is applied between the inductors 5, the attraction growing with the approach of an inductor, which leads to a highly unstable band center position. This results in the problem during operation of the device that the metal strand 1 cannot run freely and centrally through the guide channel 4 between the activated inductors due to the attraction of the inductors 5.
• a control circuit (not shown) is therefore provided, in which the metal strand 1 is acted on, preferably via additional electromagnetic coils (also not shown).
• additional electromagnetic coils also not shown.
• the superimposition of the magnetic fields of the inductors 5 and the additional coils (not shown) ensures that the metal strand 1 maintains a defined, preferably central, position.
• the magnetic field of the inductors 5 can be strengthened or weakened depending on the control (superposition principle) by means of the additional coils.
• the two inductors 5 are arranged essentially mirrored to the center plane 7 of the guide channel 4 and are at a distance Y from one another.
• the height Ho of the inductors - viewed in the direction of conveyance R of the metal strand 1 - is the same for both inductors 5.
• the position measuring sensors (coils) 6 and 6 ' are used, which are designed as wire windings without a core. They are arranged in front of the respective inductors 5 in the electromagnetic field and are used to measure a voltage U ⁇ n d induced in the coils 6, 6 '. and U
• the voltage induced in the coils 6, 6 ' is measured without current (high-resistance) in order not to influence the field of the inductors 5 (and possibly the additional coils).
• the coils 6, 6 ' are those which have one or more turns of a conductive wire metal (e.g. copper wire).
• the wire material is wound round, oval, rectangular or in a similar form around a center.
• the coils 6, 6 'of an associated pair are each arranged between inductor 5 and steel strip 1; with respect to the center plane 7 of the guide channel 4, they are arranged in a mirrored manner, ie the height H of the coil 6, 6 ', the width L of the coils 6, 6' (see FIG. 2) and the distance Xi or X 2 of the coils 6, 6 'from the inductor 5 are the same. It should be noted that the equality of the distances Xi and X 2 is not a necessary requirement.
• the measured induced voltage in the coils 6, 6' changes depending on the position s of the metal strand 1. This is due to the feedback of the metal strand 1 in the magnetic field.
• the proposed concept is based on the combination of inductor arrangement and measuring coil position within the magnetic field, the effect of the interaction of the metal strand 1 with the magnetic field of the electromagnetic seal being used.
• A surface of the coil perpendicular to the magnetic field
• B magnetic field strength
• the induced voltage Uin d in the coil 6, 6 ' is thus proportional to the field strength at the location of the coil.
• the position of the coils 6, 6' results between the coils in the electromagnetic field of the inductors 5 without a metal strand 1 arranged between the coils 6, 6 '. correspond- the difference signal, ie a voltage difference U ⁇ nd .
• the voltage difference is U
• this difference signal Uin d of the coils 6, 6' changes when the coils 6, 6 'are in a fixed position.
• the metal strand 1 now occupies different positions s between the inductors 5 and the upstream coils 6, 6 ', different differential signals of the coils 6, 6' result depending on the position s.
• the position s of the metal strand 1 results from the difference between the locally fixed coils 6, 6 'and their arrangement in accordance with the parameters height position H of the coils 6, 6', width position B of the coils 6, 6 'and distance Xi and X2 of the coils 6 , 6 'from inductor 5.
• Uind 2 induced voltage in the coil 6 ', nt .: number of turns of the coil 6, n 2 : number of turns of the coil 6', fi: factor for the coil 6 as a function of the position of the
• the voltage induced in the coils 6, 6 ′ is measured in part of the measuring device 8.
• the part of the measuring device 8 in which this measurement is carried out is followed by a difference generator 9 in which the voltage difference
• Uin d is determined, i.e. the difference between the induced voltage
• Difference former 9 is arranged downstream of the measuring device 8, in which, based on the voltage difference U ⁇ nc ⁇ , the position s of the metal strand 1 can be calculated back relative to the center plane 7 of the guide channel 4.
• the function curve for the position s of the metal strand stored here depends on the voltage difference U ⁇ n d

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Computer Hardware Design (AREA)
• Coating With Molten Metal (AREA)

Applications Claiming Priority (3)

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• 2002
  • 2002-11-30 DE DE10255995A patent/DE10255995A1/de not_active Withdrawn
• 2003
  • 2003-11-11 TW TW092131446A patent/TWI319444B/zh not_active IP Right Cessation
  • 2003-11-15 AU AU2003282097A patent/AU2003282097B8/en not_active Ceased
  • 2003-11-15 WO PCT/EP2003/012791 patent/WO2004050941A1/de active Application Filing
  • 2003-11-15 BR BR0316809-3A patent/BR0316809A/pt not_active Application Discontinuation
  • 2003-11-15 US US10/536,871 patent/US8304029B2/en not_active Expired - Fee Related
  • 2003-11-15 CN CN200380104586A patent/CN100580131C/zh not_active Expired - Fee Related
  • 2003-11-15 PL PL375349A patent/PL213013B1/pl not_active IP Right Cessation
  • 2003-11-15 EP EP03773714A patent/EP1567686A1/de not_active Withdrawn
  • 2003-11-15 KR KR1020057009603A patent/KR101005894B1/ko not_active IP Right Cessation
  • 2003-11-15 RU RU2005120688/02A patent/RU2338003C2/ru not_active IP Right Cessation
  • 2003-11-15 MX MXPA05005310A patent/MXPA05005310A/es active IP Right Grant
  • 2003-11-15 CA CA2507345A patent/CA2507345C/en not_active Expired - Fee Related
  • 2003-11-15 JP JP2004556144A patent/JP4431049B2/ja not_active Expired - Fee Related
  • 2003-11-28 MY MYPI20034563A patent/MY138270A/en unknown

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