Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
  • B22D11/16—Controlling or regulating processes or operations
  • B22D11/20—Controlling or regulating processes or operations for removing cast stock
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
  • B22D11/06—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21B—ROLLING OF METAL
  • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
  • B21B1/46—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting
  • B21B1/463—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting in a continuous process, i.e. the cast not being cut before rolling
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
  • B22D11/06—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars
  • B22D11/0622—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars formed by two casting wheels
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
  • B22D11/12—Accessories for subsequent treating or working cast stock in situ
  • B22D11/1206—Accessories for subsequent treating or working cast stock in situ for plastic shaping of strands
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21B—ROLLING OF METAL
  • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby

Definitions

• the invention relates to a casting and rolling system for steel strips and a control system therefor.
• the object is achieved in that individual system parts are optimized with regard to their interaction to produce a strip suitable for further processing and are operated in coordination with one another.
• the tuning is preferably optimized by a neurofuzzy system.
• Slider closure drive with pouring jet control on the tundish or forehearth runs into a pre-cooling device, possibly also into an inlet mold, and there the pouring level, e.g. by radiometric measurement, for example with a measuring device from Dr. Berthold, set to an accuracy of ⁇ 3 mm.
• This setting is independent of the cross section of the distribution and / or pre-cooling device. This can be open at the top or designed as a chamber.
• a coolant control and, if necessary, a stirring device in the form of an electrical coil are provided for the distribution and precooling device. This can be made in one or more parts.
• Pre-cooling device can be designed as an inlet mold, in particular for thicker cross sections, but it can also be designed as a distribution channel or as a box-like attachment with a cover.
• the advantageously controllable training as described in DE 40 30 683 AI, is appropriate.
• the pair of casting rolls advantageously has a coolant control as well as a power and position control and in particular a momentary shape calculation.
• the shape of the casting rolls is aligned to the requirements of the downstream rolling devices in such a way that they deliver a tolerance-compliant strip with a minimum of adjustment.
• a rectangular exit profile has been found to be particularly suitable, which advantageously has spherical edges, for example.
• Behind the casting rolls there is advantageously an electromagnetic belt tension control and corresponding belt deflection devices, which at least partially replace the previously usual rolls, which can give rise to surface defects or promote the occurrence of edge cracks, particularly in continuous operation.
• inductive strip temperature distribution setting devices and a pressure water descaling device are arranged directly in front of the first forming roller in this area.
• the casting speed is preferably approximately 6 to 10 m / min.
• Single or multi-part line inductors are used for edge temperature adjustment and plate inductors that can be individually switched on and off, if necessary, for temperature homogenization. With these measures, an adjustment of the inlet temperature of the cast strip into the first roll stand is possible even with a predetermined temperature profile across the width.
• the entry temperature of the strip into the forming rolls like the casting temperature, is essentially set according to the alloy, ie the steel quality and the final dimension to be achieved during the rolling, ie the degree of deformation by the rolls.
• Simple duo or quarto roll stands are provided as roll stands, which have at least one roll gap adjustment and a roll bending device.
• the target profile and the target cross-section are set, as far as possible, which is also influenced by the reel pulling force.
• a heat treatment zone is provided behind the last stand, one to three stands, depending on the degree of deformation required to achieve the final cross section, which has inductive devices and possibly also cooling devices. Pendulum annealing is carried out here, for example to influence the grain. Furthermore, a temperature maintenance zone in front of the reel be provided. This results in a controlled heat treatment from the rolling heat.
• Thickness and profile measuring devices are advantageously located behind the rolls in order to control the roll setting, roll bending and the pull-out force from the rolls in order to achieve a tolerance-compliant strip.
• the entry profile into the rollers is advantageously determined by calculation, the calculation can be checked by measurement. The calculation goes e.g. from the solidification data of the alloy, the calculated instantaneous shape of the casting rolls and possibly from the strip temperature profile across the width.
• the inductive devices and the casting equipment are advantageously controlled and regulated by an automation system based on Siemens "SIMATIC S5", while the casting rolls, the forming rolls and the reel advantageously control and regulation based on Siemens "Symadin D ".
• the automation devices are advantageously connected to one another and to a control unit by a bus system.
• the finished rolled strip has profile deviations below the cold rolling entry tolerance of approximately max. ⁇ 0.025 mm for a 4 mm tape.
• the individual automation and measuring devices are organized in particular in technology-related automation groups and connected to one another by a feedforward-feedback control system.
• the control system has an empirical value matrix with an influencing link in the basic form of a self-optimizing neural network with fuzzy input data and automatically generated expert knowledge. This results in a superimposed control system, the relatively simple individual units in an inexpensive design for producing a crack-free strip with tolerances within the control limits of a downstream cold rolling mill can connect and thereby automatically brings with it the experience of how the individual units will react to changed input values and procedure behavior.
• the tundish or forehead outflow control takes place in a pouring tube or the like, by means of slides with an electric drive, depending on the inlet casting level and predetermined requirements, such as the strip thickness.
• the inlet casting level or level above the casting rolls can be determined not only by radiometric, but also by optical or float measurements.
• the necessary coolant control of the inlet area, etc. takes place depending on wall thermocouples or the data of the tundish outflow control in connection with an outflow measurement.
• An empirical value matrix is also advantageously used for this, which e.g. the alloy influences are taken into account.
• the casting rolls have a speed and torque control, and the deformation energy currently required is determined very advantageously by cyclical releases of the speed and torque control.
• the greater the deformation energy currently required the higher the union zone of the two solidification shells formed on the casting rolls above the connection plane of the center lines of the casting rolls and vice versa.
• the deformation energy currently required is therefore a good control variable.
• breakthroughs on the exit side can be avoided in a very advantageous manner, as can an excessively high position of the solidification shell union zone.
• Hanging the union zone to one side can be compensated for by selective cooling.
• DE 40 21 197 AI shows more about the one-sided hanging of the union zone. The unilateral hanging of the union zone is noticeable eg based on the outlet temperature profile.
• the casting rolls are controlled in relation to their axis position (distance, offset). Their actual position and shape can be determined, for example, by continuous IR laser measurements and corrected if necessary.
• the amount of coolant is adjusted, in particular according to the specifications of the inlet area and the casting roll speed. Minor crowning corrections are possible using electrical means, such as induction heating.
• the extraction of the cast strip is regulated taking into account the small maximum tensile stress on the exit side of the casting rolls.
• This regulation can be viewed either in connection with the regulation of the roll stands, but also as the regulation of a decoupled stand with a tension regulation by electromagnetic means.
• a control to constant, maximum mass flow is optimal, depending on the maximum cooling capacity with an adaptation of the roll speed to the casting roll speed.
• a strip edge temperature and shape check is advantageously carried out. Both the strip edge temperature and the strip edge shape can be done by regulating the cooling and position of the side elements of the casting rolls.
• the side elements of the casting rolls are advantageously arranged on the circumference of the casting rolls and work advantageously in connection with an inductive heating or cooling as well as a position control, e.g. according to an empirical value matrix.
• the surfaces of the casting rolls advantageously have a structural pattern, a herringbone or zigzag pattern being particularly advantageous.
• the structure recesses can be cleaned, for example, by spraying water in connection with a brush system, it being advantageous to control the cleaning by a laser, which can possibly be reworked.
• an electromagnetically operating belt vibrating device is advantageously provided, which is supplemented if necessary by a likewise advantageous electromagnetic stage or casting roll vibrating device.
• an image and pattern recognition unit for example with infrared cameras, is advantageously located between the casting rolls and the first forming roll stand, with which the surface condition of the strip is checked.
• a profile and thickness measuring device may be located in front of the roll stands, which in particular carries out a profile and thickness trend evaluation. This information is particularly useful for the neuro-fuzzy system with its if-then rules, but it can also be evaluated conventionally by differentiation. The same applies to the other trends that are considered.
• inductive heat treatment with predetermined temperature profiles is advantageously carried out, for example, pendulum annealing at 720 ° C. and / or a subsequent holding at 500 ° C. to 550 ° C. in the case of alloy steel.
• the downstream reel has a tension control in order to achieve the predetermined final thickness of the strip on the last roll stand while maintaining a minimum and maximum tension.
• the superimposed control system which also works largely on the basis of mathematical models with adaptation on a neuro-fuzzy basis (largely during network training), is used in particular to coordinate the profile and strip condition achieved in the casting rolls with the downstream units. It is thus possible to advantageously use the casting rolls as well as the forming rolls, e.g. to operate without complex shifting devices (forming rolls) or devices for changing the crown (casting rolls). Based on the empirical value matrix, an optimal response to the existing conditions can be achieved relatively quickly for the different entry conditions into the casting rolls, whose behavior in operation can be determined by simulation and / or tests during commissioning and for the entry conditions into the roll stands.
• the running-in conditions in particular the running-in temperature, taking into account the available cooling capacity, a tolerance-compliant band can be achieved after a relatively short time with very simple units.
• estimated values of the parameters of the fuzzy sets are sufficient for the empirical value matrix, and these are improved with the aid of the self-learning neural network.
• the associated fuzzy rules for processing the fuzzy sets are verified after the previous effect simulation (in particular with regard to critical states) as part of the trial operation and are also included in the empirical value matrix, with the neural network weighting the fuzzy rules accordingly Requirements changed.
• Cooling zones 1, 11 and III individually controllable cooling zones with regard to the cooling capacity
• strip profile, strip thickness measuring devices e.g. designed as laser measuring devices, integrated edge profile measuring devices,
• Casting roll surface parts e.g. made of copper beryllium, possibly coated with tungsten carbide or other carbides

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Continuous Casting (AREA)
• Metal Rolling (AREA)
• Heat Treatment Of Sheet Steel (AREA)
• Furnace Housings, Linings, Walls, And Ceilings (AREA)
• Treatment Of Steel In Its Molten State (AREA)
• Coating With Molten Metal (AREA)
• Control Of Metal Rolling (AREA)

Applications Claiming Priority (4)

Publications (2)

Family

ID=6888675

Family Applications (1)

Country Status (12)

Cited By (1)

Families Citing this family (9)

Family Cites Families (10)

• 1993
  • 1993-12-21 WO PCT/DE1993/001228 patent/WO1995015233A1/fr active IP Right Grant
  • 1993-12-21 RU RU96115034A patent/RU2121408C1/ru active
  • 1993-12-21 EP EP94902613A patent/EP0732979B1/fr not_active Expired - Lifetime
  • 1993-12-21 CA CA002177831A patent/CA2177831C/fr not_active Expired - Lifetime
  • 1993-12-21 ES ES94902613T patent/ES2115205T3/es not_active Expired - Lifetime
  • 1993-12-21 KR KR1019960702865A patent/KR960706382A/ko not_active Application Discontinuation
  • 1993-12-21 JP JP7515321A patent/JPH09506296A/ja active Pending
  • 1993-12-21 SK SK681-96A patent/SK68196A3/sk unknown
  • 1993-12-21 AT AT94902613T patent/ATE165029T1/de active
  • 1993-12-21 DE DE59308416T patent/DE59308416D1/de not_active Expired - Lifetime
  • 1993-12-21 BR BR9307904A patent/BR9307904A/pt not_active Application Discontinuation
• 1996
  • 1996-05-31 FI FI962295A patent/FI102737B/fi not_active IP Right Cessation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events