US3764789A - Automatic control system for hot-strip mill and the like - Google Patents

Automatic control system for hot-strip mill and the like Download PDF

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US3764789A
US3764789A US00208634A US3764789DA US3764789A US 3764789 A US3764789 A US 3764789A US 00208634 A US00208634 A US 00208634A US 3764789D A US3764789D A US 3764789DA US 3764789 A US3764789 A US 3764789A
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A Nara
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Hitachi Ltd
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    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00—Control of temperature
    • G05D23/19—Control of temperature characterised by the use of electric means
    • G05D23/1917—Control of temperature characterised by the use of electric means using digital means

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  • ABSTRACT In a cooling process for a hot-strip mill wherein cooling water is sprinkled on a strip from a plurality of spray banks thereby to cool the strip and to control the winding temperature thereof, the temperature of the strip at the inlet of the process is detected, the initial value of a function prescribing a desired temperature falling rate is calculated from the detected value, and it is applied to a first analog shift register.
  • FIG 6 39 /4O WINDING TEMPERATURE SEE E MULTIPLIER -
  • the spray bank for pre-setting is arranged on the mill side, while the spray bank for control is arranged on the winding side, whereby approximately the necessarypooling power is obtained at the pre-setting spray spray bank, while in the case where the necessary cooling power is insufficient with only the manipulation of the presetting spray bank, the cooling power is compensated at the control spray bank.
  • large-sized ON-OFF valves are used for the pre-setting spray bank, while small-sized ON-OFF valves for the control spray bank.
  • An object of the present invention is to provide an automatic control system which, in order to eliminate such disadvantages, controls a distributed product or object with distributed, manipulated variables.
  • Another object of the present invention is to provide an automatic control system which may satisfy not only the aforesaid control of the winding temperature, but also a high level of control such as the control of a temperature falling ratio or rate.
  • Still another object of the present invention is to positively utilize the distributing character of manipulating means, to thereby enhance the quality of products and to simplify the control method thereof.
  • the present invention is characterized in that,
  • the whole distribution of manipulated variables exerted upon the product or object is considered as one pattern, the manipulated variables are distributed so as to coincide with a standard pattern of the manipulated-variable distribution as is required for a desired product quality and the standard condition of the process, to thereby be fed to the product or object, and the standard pattern is altered in response to changes in the conditions of the process, etc.
  • FIG. 1 is a block diagram showing the basic construction of the present invention
  • FIG. 2 is a, schematic diagram showing an embodiment of the present invention
  • FIGS. 3 and 4 are schematic diagrams each showing a practical embodiment of the construction of the es sential portions of the embodiment in FIG. 3;
  • FIGS. Sa-Se show curve diagrams which illustrate a variety of standard distribution patterns of manipulated variables
  • FIG. 6 is a block diagram showing the construction of a feedback control system added to the above embodiment
  • FIG. 7 is a schematic diagram showing a temperature model of a slab
  • FIGS. 8 and 9 are diagrams showing another embodiment of the present invention.
  • FIG. 10 is a schematic diagram showing a practical embodiment of the construction of the essential portions of the embodiment in FIG. 9.
  • the present invention has successfully studied the merits which the distributed manipulating means has for the aforesaid process.
  • the invention provides a feed forward control system in which the whole distribution of manipulated variables exerted upon the controlled system by such manipulating means is dealt with as one pattern, the distribution pattern of the manipulated variables is made so as to satisfy a condition of the process as enhances the product quality (for example, a standard pattern of the manipulated-variable distribution as provides the reference winding temperature and the desired temperature-falling rate), and the condition is altered in response to a change in the state of the process.
  • a control aim to control changes-versus-time of such a distributed, controlled variable.
  • a fixed period of time is required in order to cool the hot strip to a reference winding temperature and, hence, the control of the falling rate of the strip temperature may be regarded as such a control aim. Accordingly, if the temperature falling rate may be controlled so as to coincide with a function capable of enhancing the product quality, products of higher quality than in the prior art may be obtained.
  • manipulated variables exerted upon the product or object may be distributed so as to make the distribution pattern a predetermined one.
  • a distributed manipulating means is used in the present invention.
  • the distributed, manipulated variables in accordance with the desired pattern may be imparted to the object or product.
  • the present invention may be defined as a system effecting a pattern-like control with the distributed manipulating means.
  • the distributed, manipulated variable density (manipulated variable per unit length) fed from the re spective positions of the distributed manipulating means is changed in conformity with the lapse of time corresponding to the movement of the product or object, and is thereby controlled so that the distribution pattern of the manipulated variable may coincide with a function representing the desired pattern. That is to say, the manipulated variables imparted to the product or object with its movement according to a specific state are determined by changes-versus-time in the distributed manipulated-variable densities given at the respective positions of' the distributed manipulating means. In this manner, the patterndike control with the distributed manipulating means is suited to the feed forward control of the process having the distributed product or object.
  • FIG. 1 shows the basic construction of the aforesaid system of the present invention.
  • numeral 1 designates a process
  • 2 a distributed product or object which moves between the input and output of the process
  • 3 an initial-value detector for a controlled variable
  • 4 a function generator which generates a function prescribing changes-versus-time in the controlled variable
  • 5 and 6 analog shift registers
  • 7 and 8 sampling devices for taking out outputs from the respective memory components constituting the registers
  • 9 a calculating device for the density of manipulated variables
  • 10 a distributor 11 an analog memory for storing the manipulated-variable density distributed by the distributor, 12 a driving device, and 13 a manipulating means distributed and arranged along the process 1 and consisting of a plurality of manipulators.
  • the analog shift register has a plurality of analog storage elements, e.g., analog core elements, connected in series, and has the function of successively shifting an input analog quantity to the next element by means of shift pulses SP simultaneously applied to the respective elements.
  • Analog shift registers per se are well known.
  • the shift pulses are produced by a timer 14 every time the object or product 2 is moved by a unit distance (the disposed interval between each manipulator). To the timer 14, there is applied an output signal V(t) from a speed detector 15 of the product or object 2. Further, at every movement of the product or object 2 by the unit distance, the timer 14 applies simultaneously to the respective analog storage elements of the analog register 6 a timing signal which represents the moving time T of the controlled system.
  • the functions prescribing the changes-versus-time in the controlled variable are previously evaluated experimentally and theoretically, and are preset in the function generator 4.
  • the function generator 4 generates a functional output in response to the initial value of the controlled variable detected by the detector 3, and applies it to the first element of the analog shift register 5.
  • the calculating device 9 calculates a required manipulated-variable density from the functional output and the moving time of the product or object 2.
  • the manipulated-variable density is used to cause the change-versus-time in the controlled variable to coincide with a desired pattern as has been previously stated, it should be distributed in correspondance with the respective spatial positions of the product or object 2.
  • the functional output and the moving time are shifted into the analog shift registers 5 and 6 by the shift pulses SP, and they are taken out from the respective elements of the respective registers by the sampling devices 7 and 8.
  • the distributor l0 distributes the mainpulated-variable density, calculated by the calculating device 9, to the respective manipulators of the manipulating means 13 through the analog memory 11 and the driving device 12 in synchronism with the sampling devices.
  • the operating speeds of the sampling devices and the distributor are made sufficiently high in comparison with the shift period in the registers (the moving speed of the product or object 2), so that all the sampling and distributing operations may be completed before the contents of the registers are shifted.
  • the manipulated-variable densities required at the respective spatial positions of the product or object 2 may be obtained, and they are successively fed from the respective manipulators with the movement of the product or object 2.
  • the manipulated variables are fed to the product or object 2 in such a manner as to realize a predetermined standard pattern in conformity with the movement of the product or object and, hence, the changes-versus-time in the controlled variable may be controlled so as to coincide with the pattern. While the standard pattern is determined dependent upon the pattern of the changesversus-time in the controlled variable as is required to enhance the quality of a product and on the standard condition of the process, it may of course be suitably altered.
  • T(t) represents the temperature of one point on the strip
  • t a lapsing period of time of the strip movement from the inlet of the process to this point
  • f [T(t)] a function prescribing the pattern of the temperature falling rate at the above-mentioned point, which is previously evaluated from experimental and theoretical studies. Accordingly, the temperature T(t) as the controlled variable should be so controlled as to become:
  • T(()) represents the strip temperature at the inlet (the initial value).
  • equation (3) may be made equal to equation (1), the relation between the strip temperature and the spray cooling power to be manipulated is evaluated as the following expression:
  • FIG. 2 shows an embodiment of the cooling and winding process according to the system of the present invention.
  • the detector 3 detects the initial temperature T(O), and transmits it to the function generator 4.
  • the function f [T(t)] is kept set in the function generator 4, and the functional output f [T(O)] thereof is applied to the first element of the analog shift register 5.
  • the timer 14 transmits the shift pulses SP to the analog shift registers 5 and 6 in synchronism with the movement of the strip 2, and therewith, it applies the timing signal T to the respective elements of the register 6 at each movement of the strip 2 by the unit distance (the spray interval Ax).
  • t represents the lapsing time having been accumulatedin the element immediately before the n-th I one, while ida? the moving time T for the unit distance.
  • FIG. 3 shows a practical embodiment of the timer 14.
  • numerals l6 and 17 designate integrators, 18 a comparator, 19 an OFF delay element, 20 an ON delay element, and 21 and 22 switches.
  • a speed detection signal V(t) is applied from the speed detector 15 for the strip.
  • a voltage corresponding to the unit distance Ax is applied to one of the inputs of the comparator 18, while an output signal of the integrator 16 is applied to the other input.
  • an output signal is produced from the comparator 18, it is transmitted to the analog shift registers. Simultaneously therewith, it is applied through the OFF delay element 19 and the ON delay element 20 to the reset switches 21 and 22, to turn them ON to ground the integrators 16 and 17.
  • the OFF delay element 19 has the function of delaying an of operation by a certain period of time 1'
  • the ON delay element 20 has the function of delaying an on operation by a certain period of time 1'.
  • a variety of types of these elements are commercially available.
  • the shift pulse SP having a width r is produced'as the output signal of the comparator 18 for every movement of the strip 2 by a unit distance Ax, while the integrator 17 is grounded each time. Accordingly, if a certain fixed voltage E, isapplied to the input of the integrator 17, a voltage E proportional to the moving time T for the unit distance Ax is obtained at the output thereof.
  • the voltages B are accumulated in the respective elements of theanalog shift register 6.
  • FIG. 4 illustrates a practical embodiment of the calculating device 9.
  • numeral 23 indicates an exponential-function generator, 24 and 25 multipliers, 26 the same function generator as function generator 4, 27 an operational amplifier, 29 a comparator, and 30 a switch opened and closed by the outputs of the comparator 29.
  • the exponential-function generator 23 produces an exponential function e"" in response to the time lapse 1,, taken from the analog shift register 6 by the sampling device 8.
  • the aforesaid functional output f [T(O)] stored in the element of the analog shift register 5 is taken out by the sampling device 7, to be applied to one of the inputs of the multiplier 24, while the output of the exponential generator is applied to the hQ Li Bfl -A a r921!
  • the multiplying signal is applied to one of the inputs of the multiplier 25, while a thickness output from a detector 32 shown in FIG. 2, for the thickness h of the strip 2 is applied to the other input.
  • the inverse-function output T( t,,) is also applied to one of the inputs of the comparator 29, and is compared with the reference winding temperature T applied to the other terminal 31.
  • the switch 30 contacts the input terminal 33, and hence, the spray cooling power m(x, t,,) is distributed to a predetermined element of the analog memory 11 by means of the distributor 10.
  • T( 1,.) T the switch 30 contacts grounded terminal 34, and hence, m(x, t,,) becomes zero.
  • the respective elements of the analog memory 1 l are connected to the driving device 12 comprising a servoamplifier, etc., continuous manipulating valves 35 are continuously manipulated by said device, and cooling water supplied from a pump 36 is sprayed onto the strip by a plurality of sprays 37.
  • the quantity of the cooling water sprayed in the strip corresponds to the cooling power m(x, t Moreover, as previously stated, the cooling water is sprayed from the sprays corresponding to the respective spatial positions of the strip, with the movement of the strip.
  • the respective parts of the strip are cooled to the reference winding temperature at a temperature falling rate conform ing to a desired pattern.
  • FIGS. a-5e illustrate standard distribution patterns of the aforesaid spray cooling power.
  • the quantity of the cooling water sprayed from the respective sprays 37 distributed and arranged from the inlet to the outlet, is controlled in the manner above described and so as to conform to one of the patterns.
  • the standard distribution pattern is represented as in FIG. 5a for, e.g., h, V(t), T(O) and T
  • FIG. 5b depicts for 2h, V(t), T(O) and T
  • FIG. 5b depicts that for h, l.5V(t), T(O) and T as in FIG. 50
  • FIG. 50 that for h, V(t), T(O) AT (AT 0) and T as in FIG.
  • a winding-temperature detector 38, a correcting device 39 and a multiplier 40 are employed as shown, by way of example, in FIG. 6.
  • the correcting device 39 generates a correcting signal E in response to an error or deviation e between a wind ing temperature T, detected by the detector 38 (the final controlled variable) and the reference temperature T
  • the correcting signal E is expressed by E l B(e), where B(e) is a function representing the correcting ratio of the cooling power as is required for the error e and being previously set, and 8(0) 0.
  • the correcting signal E and the cooling power m(.x, t,,) calculated by the calculating device 9 are subject to multiplication in the multiplier 40, and a resulting corrected cooling power is fed to the distributor 10.
  • the spray cooling process for a slab in the continuous casting has similar characteristics to those in the hot strip.
  • the product or object in the former case is the temperature distribution of three dimensions within the slab, and is not so simple as that for temperature control at points in the strip. More specifically, for the hot strip, since the temperature difference between the edge parts and the inner part of the cross section of a strip is negligible, the surface temperature may be regarded as the controlled variable.
  • the temperature distribution pattern in the cross section of the slab should be considered as the controlled variable.
  • a temperature model representing such pattern there may be considered a set of rectangular parallelepipeds each having, as shown in FIG.
  • t represents a time lapse with respect to the time at which the i-th slab cross section has passed through a mold outlet
  • A the heat conductivity of the inner part of the slab
  • T the heat conductivity of the inner part of the slab
  • T the heat conductivity of the inner part of the slab
  • T the heat conductivity of the inner part of the slab
  • T the heat conductivity of the inner part of the slab
  • g1 one of indices indicating directions, which are determined as l, 2, 6, respectively, for the upward, downward, leftward, rightward, frontward and backward directions.
  • X takes the value of 0 at the surface of the slab and the value of l at the inner part of the slab, with respect to the m direction of the j-th cube at the i-th slab cross section.
  • X,,,, takes the inversed value of X,,,,,.
  • C represents the specific heat of the slab, while p the density of the slab.
  • the symbol k,, (L,) represents the cooling power density of the spray as is exerted, when the i-th slab cross section has arrived at L, from the mold outlet along the slab, upon the slab at said cross section from the m direction.
  • V(t,) indicates a speed when the i-th cross section of the slab has experienced the lapse of the above-mentioned period of time t,.
  • control conditions given by equation (8) may not be independently selected as is possible in the previous equation (2), and should be selected from among those which may be realized by the formulae (6) and (7).
  • Eqaution (6) is solved by putting thereinto V(t) and the initial value 'n',( At), At 0 of 1r,(t,) and replacing k,,,(L,) with k,,,,(t,), and thus, k,,,,(t,) with which the most preferably relation between 1r,(t,) and d1r,(t,)/dt, is obtained is previously evaluated.
  • k,,,,(t,) shall be re-evaluated for different materials and/or configurations of the slab, and it shall be equal to 0 after T,,,,(t,) has coincided with a reference temperature T,,,,,.
  • the initial value is not 1r,(0) but 1r,( Al)
  • the desired manipulated-variable distribution k,,,(L,) may be evaluated from the above-mentioned k,,,,(t,) in expression (1 l
  • T,,,,(t,) is T,,,,(t,) which is evaluated by substituting k,,,,(t,) into k,,,(L,) in equation (6).
  • T,,,,(t,) indicates the temperature of a specified surface part among T,,(t,) at point of the slab, while T,,,,(0) represents the detected temperature value of the surface part at t, 0.
  • k,,,(L,) should be evaluated on various points of the slab within the range L, 0-L,, (the distance from the mold outlet to the temperature detecting point of the cooling process). Whether or not L, falls within the range is discriminated by the above-mentioned expression (7).
  • FIGS. 8 and 9 illustrate an embodiment of a spray cooling process for a slab in a continuous casting process which adopts the aforesaid feed forward control system.
  • a mold device 41 has the function of injecting smelted steel into a mold, subsequently water-cooling the mold to solidify the contact area between it and the smelted steel, and continuously drawing out a slab.
  • the slab drawn out is introduced into a cooling process similar to that in the case of the strip.
  • a temperature detector 42 detects the surface temperature T,,,,(0) of the specified part of the slab, and feeds it to a function generator 43.
  • the function generator 43 has previously set therein a function based on expression (10), and generates At', corresponding to the temperature T,,,,(0).
  • Analog shift registers 44 and 45, a timer 46 and a speed detector 61 have the same functions as in the case of the embodiment in. FIG. 4.
  • a calculating device 47 serves to calculate the manipulated-variable distribution k,,,(L,) on the basis of expression (1 l and an example of construction thereof is shown in FIG. 10.
  • numeral designates an adder, while 51 is a function generator; Ar, and t, taken out from the analog shift registers 44 and 45 by means of sampling devices 48 and 49 are fed to the adder 50, and therewith, an added output t, Al, is applied to a function generator 51.
  • the function generator 51 has previously set therein a function based on expression (ll), and generates the manipulated variable k,,,(L,) corresponding to the added output.
  • Cooling water responsive to the manipulated variables is subsequently sprayed onto the slab, and means therefor relies on a construction similar to that in the embodiment in FIG. 4.
  • numeral 52 represents a comparator, 53 a switch opened and closed by the comparator, 54 a distributor, 55 an analog memory, 56 a driving device, 57 a pump, 58 a continuous manipulation valve, 59 a spray, and 60 a pinch roll.
  • a construction similar to that in the case shown in FIG. 6 may be employed.
  • a rational and effective feed forward control capable of satisfying even a high level of control such as a temperature falling rate may be realized, e.g., in a cooling process for a hot-strip mill having a distributed product or object.
  • a high level of control such as a temperature falling rate
  • An automatic control system for a distributed, controlled object which moves between an input and an output of a process, comprising:
  • an initial-value detector for a controlled variable of the controlled object for a controlled variable of the controlled object; a function generator to which the initial-value of the controlled variable from said detector is applied for generating a function prescribing changes-versus-time in said controlled variable;
  • a first analog shift register for storing a functional output of said function generator
  • a second analog shift register for accumulating a moving period of time of said controlled system at every movement thereof by a unit distance
  • a timer for generating at every movement of said controlled system a shift signal for successively shifting the contents of each analog storage element of both said registers to the adjoining element and a signal representing said moving period of time;
  • sampling devices for taking out the contents of said each element of both said registers
  • manipulating means for successively supplying said manipulated-variable density from said memory to said controlled object, said manipulating means having a plurality of manipulators which are arranged in a manner to be distributed along said controlled object.
  • An automatic control system further comprising a detector for detecting a final value of said controlled variable
  • An automatic control system for controlling the characteristics of an object during a process performed on said object, through which said object passes through a processing means comprising:
  • first means coupled to said object at its input to said processing means, for detecting a first parameter to be employed as a control variable for controlling said characteristics
  • second means responsive to said first means, for gencrating a function of said control variable with respect to time and producing a signal representative of said function
  • third means responsive to the rate of the entry of said object into said processing means, for generating a first timing signal representative of each increment of movement of said object into said processing means and a second timing signal representative of the time period which has elapsed from the initial entry of said object into said processing means;
  • fourth means responsive to said function representative signal and said first timing signal, for sequentially storing portions of said function signal as they are produced and as said object moves through said processing means;
  • fifth means resonsive to said first and second timing I signals, for storing said second timing signals and for generating a signal representative of a lapse of time from the initial movement of said object into said processing means;
  • sixth means responsive to the output of said fourth and fifth means, for sampling the outputs thereof for each of said increments of movement of said object through said processing means;
  • eighth means responsive to the characteristic control signal output of said seventh means, for applying at least one input to said object passing through said processing means, so as to control the characteristics of said object in accordance with said characteristic control signal.
  • said eighth means comprises an anlog memory to which the output of said seventh means is coupled, a plurality of distributors for receiving the output of said memory and generating a plurality of manipulating signals;
  • a plurality of manipulating means for receiving said manipulating signals and controlling the characteristics of said object in response thereto.
  • said fourth and fifth means each comprises a shift register for shifting the inputs thereto in response to saidfirst timing signal.
  • said seventh means comprises a predetermined function generator, receiving the output of said fifth means, for generating a function of the output thereof, a first multiplier for multiplying the output of said predetermined function generator by the output of said fourth means, a second multiplier, for multiplying the output of said first multiplier by a signal representative of a prescribed parameter of said object passing through said processing means, an operational amplifier connected to the output of said first multiplier and a function generator for feeding back the output of said operational amplifier to the input thereof, a divider circuit for dividing the output of said second multiplier by the output of said operational amplifier, a comparator circuit, for comparing the output of said operational amplifier with a threshold level, and a switching circuit, for supplying the output of said divider circuit to said eighth means in response to the output of said comparator circuit.
  • said third means comprises a first integrator circuit for integrating a signal representative of the rate of entry of said object into said processing means, a comparator circuit for comparing the output of said first integrator with a preset rate level and generating said first timing signal as a result of said comparison, a series delay circuit for delaying said first timing signal, a second integrator, responsive to an input voltage, for integrating said voltage in accordance with the output of series delay circuit.
  • said seventh means comprises a predetermined function generator, receiving the output of said fifth means, for generating a function of the output thereof, a first multiplier for multiplying the output of said predetermined function generator by the output of said fourth means, a second multiplier, for multiplying the output of said first multiplier by a signal representative of a prescribed parameter of said object passing through said processing means, an operational amplifier connected to the output of said first multiplier and a function generator for feeding back the output of said operational amplifier to the input thereof, a divider circuit for dividing the output of said second mulitplier by the output of said operational amplifier, a comparator circuit, for comparing the output of said operational amplifier with a threshold level, and a switching circuit, for supplying the output of said divider circuit to said eighth means in response to the output of said comparator circuit.
  • a system according to claim 9, further including ninth means, coupled to said object, for detecting a second parameter to be employed as a correcting variable, and responsive to the output of said seventh means, for correcting the output thereof with respect to said second parameter and coupling said corrected output to said eighth means.
  • said fourth and fifth means each comprises a shift register for shifting the inputs thereto in response to said first timing signal and wherein said object comprises a slab to be cooled during a continuous casting process carried out by said processing means on said slab, said first parameter corresponds to the temperature of said slab, said prescribed parameter corresponds to the thickness of said slab, said threshold level corresponds to a threshold temperature level, said predetermined function-comprises an exponential function, and said manipulating means comprises a plurality of cooling elements for cooling said slab.
  • said ninth means comprises a winding temperature detector, for generating a signal representative of the winding temperature for said slab, a correcting device responsive to the winding temperature signal and to said threshold temperature for generating an error signal representative of the difference therebetween, and a multiplier for multiplying said error signal by the output of said seventh means so as to provide a corrected characteristic control signal to said manipulating means.
  • cooling means comprises a plurality of spray nozzles distributed along said object in accordance with spaces of incremental movement thereof through said processing means.
  • said fourth and fifth means comprise a plurality of parallelarranged shift registers, corresponding to the number of surfaces of said object to be manipulated
  • said seventh means comprises an adder circuit for adding the incremental outputs of said shift registers and a function generator for generating a control output in response to the sum of said incremental outputs of said shift registers in accordance with a prescribed function, a comparator circuit for comparing the output of said function generator with a threshold level, and a switching circuit for supplying the output of said function generator to said eighth means in response to the output of said comparator.
  • said third means comprises a first integrator circuit for integrating a signal representative of the rate of entry of said object into said processing means, a comparator circuit for comparing the output of said first integrator with a preset rate level and generating said first timing signal as a result of said comparison, a series delay circuit for delaying said first timing signal, a second integrator, responsive to an input voltage, for integrating said voltage in accordance with the output of series delay circuit.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Feedback Control In General (AREA)
  • Control Of Temperature (AREA)
  • Continuous Casting (AREA)
  • Control Of Metal Rolling (AREA)
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Cited By (3)

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FR2488423A1 (fr) * 1980-08-06 1982-02-12 Saint Gobain Vitrage Procede et dispositif pour la regulation de la temperature d'une feuille de verre dans un four a plusieurs cellules
US4569023A (en) * 1982-01-19 1986-02-04 Mitsubishi Denki Kabushiki Kaisha Apparatus for controlling the temperature of rods in a continuous rolling mill
WO2019060717A1 (en) * 2017-09-22 2019-03-28 Nucor Corporation ITERATIVE LEARNING CONTROL FOR PERIODIC DISTURBANCES IN A TWO CYLINDER TAPE CASTING WITH DELAY IN MEASUREMENT

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Publication number Priority date Publication date Assignee Title
JPS5284880U (enrdf_load_stackoverflow) * 1975-12-20 1977-06-24

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US3039687A (en) * 1959-07-17 1962-06-19 Ind Nuclconics Corp Automatic process control
US3478808A (en) * 1964-10-08 1969-11-18 Bunker Ramo Method of continuously casting steel

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US3039687A (en) * 1959-07-17 1962-06-19 Ind Nuclconics Corp Automatic process control
US3478808A (en) * 1964-10-08 1969-11-18 Bunker Ramo Method of continuously casting steel

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Controlling a Complete Hot Strip Mill by Brower, Control Engineering, pp. 57 63, Oct. 1963. *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2488423A1 (fr) * 1980-08-06 1982-02-12 Saint Gobain Vitrage Procede et dispositif pour la regulation de la temperature d'une feuille de verre dans un four a plusieurs cellules
EP0047682A1 (fr) * 1980-08-06 1982-03-17 Saint Gobain Vitrage International Procédé et dispositif pour la régulation de la température d'une feuille de verre dans un four à plusieurs cellules
US4569023A (en) * 1982-01-19 1986-02-04 Mitsubishi Denki Kabushiki Kaisha Apparatus for controlling the temperature of rods in a continuous rolling mill
WO2019060717A1 (en) * 2017-09-22 2019-03-28 Nucor Corporation ITERATIVE LEARNING CONTROL FOR PERIODIC DISTURBANCES IN A TWO CYLINDER TAPE CASTING WITH DELAY IN MEASUREMENT
US10449603B2 (en) 2017-09-22 2019-10-22 Nucor Corporation Iterative learning control for periodic disturbances in twin-roll strip casting with measurement delay
US11135647B2 (en) 2017-09-22 2021-10-05 Nucor Corporation Iterative learning control for periodic disturbances in twin-roll strip casting with measurement delay

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