JP2007160316A - Method for controlling water cooling of rolled material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for controlling a water cooling operation, which method can accurately control the temperature in a finish rolling process by suppressing the effect of the remained cooling water and the recuperation time on the surface temperature of the rolled material when an interim water cooling operation is carried out for improving the quality of material in a hot rolling process for steel bars and wires. <P>SOLUTION: When the rolled material 11 is forcedly cooled in an interim water cooling zone 3 between an interim rolling mill train 1 and a finish rolling mill train 2 of a rolling apparatus for steel bars or wires, the temperature at the exit side of the top rolling mill 2a in the finish rolling mill train 2 is used as the temperature of the rolled material after the water cooling operation or the rolling load in the top rolling mill 2a is used to control the water cooling operation. As a result, the use of the temperature of the rolled material in an unstable state, in which the difference of temperature distribution is large in the cross section in the recuperation process after rolling, is unnecessary. Further, because the value measured at the early stage after the interim water cooling operation is used for the water cooling, the temperature at the exit side of the finish rolling mill train 2 can be furthermore accurately controlled to the target finish temperature. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for controlling water cooling of a rolled material in hot continuous rolling of strips such as steel bars and wire rods.

  Strips such as steel bars and wire rods (burn-in coils) can be obtained from rough rolling in which rolling mills are arranged in multiple stages from steel slabs heated to a hot rolling temperature range in a heating furnace or directly from continuous casting equipment. By hot rolling in a plurality of rolling mill rows leading to finish rolling, the cross-sectional area is sequentially reduced to produce the required dimensions and shapes. In recent years, in order to improve the quality of rolled products, such as the quality of the surface and surface properties, an intermediate water cooling zone is installed between rolling mills to force the rolled material to water-cool and control the finishing temperature to a lower temperature than before. Rolling is taking place. In such finishing temperature control, normally, the target temperature of the rolled material on the intermediate water cooling zone outlet side is determined in advance, and the cooling water flow rate is controlled so as to be as close as possible to this target temperature. The target temperature is generally the surface temperature of the rolled material.

As a control method for such a cooling water flow rate, conventionally, feedback for controlling the cooling water flow rate based on a deviation between the actual temperature of the rolled material actually measured on the water cooling zone outlet side and a predetermined target temperature on the water cooling zone outlet side has been proposed. Control, feedforward control for controlling the cooling water flow rate based on the deviation between the temperature of the rolled material actually measured on the inlet side of the water cooling zone and the target temperature on the inlet side of the water cooling zone, and the flow rate of cooling water to the next rolling material Presets are being made. For example, in Patent Document 1, a rolling mill for steel bars equipped with a rolling mill on the upstream side and a water cooling zone on the downstream side, a rolling speed detector on the rolling mill side, and a rolling material on the entry side and the exit side of the water cooling zone Each of the temperature detectors is provided, and the position of the steel bar is tracked based on the rolling speed signal from the rolling speed detector and the steel bar information, and the temperature based on the temperature signal from the inlet temperature detector is measured for the longitudinal direction of the steel bar. Tracking is performed, and the amount of water in the water cooling zone is feedforward controlled based on this temperature, and the control amount (cooling water flow rate) at this time is corrected based on the temperature signal from the outlet side temperature detector, Steel bar rolling equipment that presets the control water amount for the steel bar or the average value of the control water amount for the most recent steel bars as the control water amount for the next steel bar when the rear end passes through the water-cooled zone Definitive water cooling control method is disclosed.
JP-A-9-239423

  However, in the conventional water cooling control method and the water cooling control method disclosed in Patent Document 1, the temperature of the rolled material is the surface temperature detected. Cooling water remains on the surface of the rolled material immediately after water cooling, and surface temperature unevenness due to water cooling occurs, making accurate temperature measurement difficult. In addition, unlike the temperature distribution of the rolled material in the normal rolling process on the water-cooled zone exit side, the temperature drop in the surface layer part is larger than the temperature drop in the center part of the rolled material due to water cooling. The difference from the center temperature is large, and even if the temperature of the rolled material is measured in the reheating process after water cooling, the appropriate temperature of the rolled material represented by the average temperature in the cross section is not measured. Since the surface temperature of the rolled material in the reheating process after water cooling is a function of the reheating time, even if the cooling water flow rate in the water cooling zone is the same, that is, the temperature drop amount of the rolled material is the same, the rolling speed is different. The time (recuperation time) until the rolled material reaches the temperature detection position from the water-cooled zone exit side is different, and the surface temperature of the rolled material measured in the reheating process is different.

  FIG. 3 shows the surface temperature (Ts), center temperature (Tc), and average temperature (Tm) in the cross section in the water cooling process in the intermediate water cooling zone installed between the rolling mill rows and in the reheating process after water cooling. ). The temperature transition of the rolled material is calculated by temperature analysis based on the measured surface temperature of the rolled material before and after water cooling. Focusing on the surface temperature (Ts) of the rolled material, Ts = 740 ° C. at the intermediate water cooling zone outlet (at the end of water cooling), and when 0.1 second has elapsed after water cooling, the heat is reheated to Ts = 781 ° C. When 2 seconds have elapsed, the heat is recovered to Ts = 798 ° C. Thus, even if the recuperation time is different by 0.1 second, a temperature difference of 17 ° C. occurs in the surface temperature of the rolled material. On the other hand, the average temperature (Tm) in the cross section of the rolled material is Tm = 973 ° C. on the intermediate water cooling zone entry side (at the start of cooling), and Tm = 892 ° C. on the intermediate water cooling zone exit side (at the end of cooling). The amount of decrease ΔTm = 81 ° C., and the average temperature (Tm) in the cross section hardly decreases during the reheating process after water cooling. The difference in the surface temperature of the rolled material of 17 ° C., which occurs only when the recuperation time, that is, the time until the temperature is detected after water cooling is 0.1 seconds, is 81 ° C., which is the amount of decrease (ΔTm) of the average temperature in the cross section (Tm). On the other hand, it corresponds to about 20%, which is a large temperature difference exceeding the allowable range of temperature measurement error.

  Therefore, the problem of the present invention is that when the rolled material is water-cooled for the purpose of improving the material quality during the hot rolling process of strips such as steel bars and wire rods, the remaining cooling water and the recuperation time after the water cooling are An object of the present invention is to provide a water cooling control method capable of controlling the finish rolling temperature with high accuracy while minimizing the influence on the surface temperature.

  In order to solve the above problems, the present invention employs the following configuration.

  The method for controlling water cooling of a rolled material according to claim 1 is characterized in that a plurality of rolling mill rows are formed by rolling mills continuously arranged in multiple stages, and a cooling water flow rate adjusting means is provided between the upstream and downstream rolling mill rows. A method of controlling water cooling of a rolled material in a steel bar or wire rod rolling facility equipped with a water cooling device having a water cooling control means comprising: a downstream rolling mill row after water cooling by the water cooling device by the water cooling control means The flow rate of the cooling water supplied to the water cooling device is controlled so that the surface temperature of the rolled material on the outlet side of the first rolling mill becomes a predetermined temperature.

  In general, when forced water cooling such as intermediate water cooling is performed to control the finishing rolling temperature for the purpose of improving the material quality in the rolling process of steel bars or wire rods, the temperature of the rolling material at the outlet side of the water cooling zone, that is, the rolling material is generally used. Water cooling control such as adjustment of the cooling water flow rate is performed so that the surface temperature becomes a predetermined temperature. However, as described above, the surface of the rolled material immediately after the exit from the water-cooled zone has residual cooling water and temperature unevenness generated during the water-cooling process, so it is difficult to accurately measure the temperature of the rolled material. In addition, when the surface temperature of the rolled material is measured during the reheating process on the water-cooled zone exit side, the difference between the average temperature in the cross section of the rolled material and the surface temperature is large, and the surface temperature of the rolled material is the average temperature in the cross section of the rolled material. That is, it cannot be said that it represents the representative temperature of the rolled material. For this reason, it is desirable to measure the surface temperature of the rolled material at the time when the recuperation is completed, but it usually takes about 1 second to complete the recuperation. A sufficient distance is required between the rolling mill row on the downstream side such as a rolling mill row. For example, if the rolling speed is 6 m / s, this distance is required to be 6 m or more. In many cases, a sufficient distance cannot be obtained due to restrictions on the length of the rolling equipment. In contrast, the rolled material on the exit side of the roll hole mold that has undergone plastic deformation in a rolling mill has a uniform surface property due to metal flow, and the heat generated by plastic deformation is also greater than the center of the rolled material. Therefore, the temperature distribution in the cross section of the rolled material becomes uniform. Therefore, since the surface temperature after rolling is closer to the average temperature in the cross section of the rolled material, that is, the representative temperature of the rolled material, compared to the surface temperature in the recuperation process, the downstream rolling mill row such as the finishing rolling mill row By measuring the surface temperature of the rolled material on the delivery side of the first rolling mill and adjusting the cooling water flow rate in the water cooling zone so that this temperature matches the target temperature, the rolling temperature such as the finish rolling temperature can be accurately controlled. High-precision water cooling control is possible. Here, the leading rolling mill outlet side means the interval from the outlet side of this rolling mill to the inlet side of the downstream next rolling mill. The same applies to the following description.

  The method for controlling water cooling of a rolled material according to claim 2 is characterized in that a plurality of rolling mill rows are formed by rolling mills arranged continuously in multiple stages, and a cooling water flow rate adjusting means is provided between the upstream and downstream rolling mill rows. A water cooling control method for a rolled material in a steel bar or wire rod rolling facility equipped with a water cooling device having a water cooling control means comprising a water cooling control means comprising: Based on the deviation between the surface temperature of the rolled material on the outlet side of the first rolling mill in the rolling mill row and the preset target surface temperature, the flow rate of the cooling water supplied to the water cooling device and / or the rolling speed of the next rolled material The setting value is adjusted.

  Thus, if the set value (preset flow rate and preset rolling speed) of the cooling water supply flow rate and / or rolling speed of the next rolled material is adjusted based on the water cooling control result for the rolled material, the one rolled material described above Combined with the adjustment of the flow rate of the cooling water inside, it is possible to perform highly accurate water cooling control that can control the rolling temperature with higher accuracy from the front end side of the next rolled material.

  The method for controlling water cooling of a rolled material according to claim 3 is characterized in that a plurality of rolling mill rows are formed by rolling mills continuously arranged in multiple stages, and a cooling water flow rate adjusting means is provided between the upstream and downstream rolling mill rows. A water cooling control method for a rolled material in a steel bar or wire rod rolling facility equipped with a water cooling device having a water cooling control means comprising a water cooling control means comprising: The cooling water supply flow rate to the water cooling device is controlled so that the rolling load at the rolling mill at the head of the rolling mill row becomes a predetermined rolling load.

  If the rolling steel type, rolling speed and cross-section reduction rate are the same, the rolling load is proportional to the average temperature in the cross section of the rolled material, so the rolling load generally expressed in terms of rolling load or rolling power and the average in the cross section of the rolled material If the relationship with temperature is calculated | required, measuring a rolling load will become equivalent to measuring the average temperature in the cross section of a rolling material. Therefore, by measuring the rolling load at the first rolling mill in the finish rolling mill row, and adjusting the cooling water flow rate and / or rolling speed of the water cooling zone so that this rolling load matches the target rolling load. In addition, high-precision water cooling control capable of accurately controlling the rolling temperature such as the finish rolling temperature becomes possible.

  According to a fourth aspect of the present invention, there is provided a water cooling control method for a rolled material, in which a plurality of rolling mill rows are formed by rolling mills continuously arranged in multiple stages, and a cooling water flow rate adjusting means is provided between the upstream and downstream rolling mill rows. A water cooling control method for a rolled material in a steel bar or wire rod rolling facility equipped with a water cooling device having a water cooling control means comprising a water cooling control means comprising: Based on the deviation between the rolling load of the first rolling mill in the rolling mill row and the preset target rolling load, the set value of the cooling water supply flow rate and / or rolling speed to the water cooling device is adjusted for the next rolled material. It is characterized by that.

  As described above, if the cooling water supply flow rate and / or the set value of the rolling speed (preset flow rate and preset rolling speed) of the next rolled material are adjusted based on the water cooling control result for the rolled material, the rolled material is used as a control parameter. Even when a rolling load is used instead of the surface temperature, it is possible to control the rolling temperature more accurately from the front end side of the next rolled material in combination with the adjustment of the cooling water flow rate in one rolled material. Water cooling control is possible.

  In this invention, in the rolling process of steel bars or wire rods, when performing forced water cooling of the rolled material in a water cooling zone provided between the rolling mill rows for the purpose of controlling the finishing temperature, it is difficult to accurately measure the temperature as in the prior art. It is not based on the surface temperature of the rolled material on the water-cooled zone outlet side, so that the surface temperature of the rolled material on the outlet side of the leading rolling mill in the downstream rolling mill row of the water-cooled zone becomes a predetermined temperature, or in the leading rolling mill Since the cooling water supply flow rate and / or the rolling speed is controlled so that the rolling load coincides with the target rolling load, finish rolling is performed based on the representative temperature (average temperature in the cross section) of the rolled material. High-precision water cooling control that can accurately control the rolling temperature such as temperature can be realized.

  Embodiments of the present invention will be described below with reference to the accompanying FIGS.

   FIG. 1 shows an essential part of a steel bar or wire rod rolling facility, and an upstream intermediate rolling mill row 1 composed of rolling mills 1a to 1f and rolling mill rows 2a to 2f arranged in multiple stages continuously. An intermediate water cooling zone 3 is arranged between the finishing mill row 2 on the downstream side. In this embodiment, an inlet-side thermometer (an inlet-side temperature detector) 4 is provided on the inlet side of the intermediate water-cooling zone 3, and the outlet side of the leading rolling mill 2 a in the finish rolling mill row 2 on the downstream side of the intermediate water-cooling zone 3. Each is provided with an exit side thermometer (outside temperature detector) 5. Further, in each of the rolling mills 1a to 1f and 2a to 2f of the intermediate rolling mill row 1 and the finishing rolling mill row 2, metal-in detectors 6 and 7 for detecting the biting of the rolled material and lines for detecting the rolling speed are provided. Speed detectors 8 and 9 are provided, respectively. In FIG. 1, the metal-in detectors 6, 7 and the linear velocity detectors 8, 9 are arranged at the most downstream side of the rolling mill 1 f of the intermediate rolling mill row 1 and the most upstream, that is, the leading rolling mill of the finishing rolling mill row 2. Only 2a is described, and the other rolling mills are not shown. The biting signal, the linear velocity detection signal, and the temperature detection signal from each of the detectors are taken into the water cooling control device 10, respectively.

  From the point of time when the rolled material 11 reaches the intermediate rolling mill row 1, the water cooling control device 10 performs detailed tracking of the rolled material 11. Whether or not the rolled material 11 has reached the last rolling mill 1f of the intermediate rolling mill row 1 is detected by the metal-in detector 6. And, from the predetermined pass schedule of the rolled material, the rolling speed detected by the linear velocity detector 8, and the temperature measurement value of the rolled material by the entry side thermometer (entrance side temperature detector) 4, an intermediate A portion in the longitudinal direction of the rolled material, the temperature, and the rolling speed when passing through the water cooling zone 3 are associated with each other, and these values are linked and taken into the water cooling control device 10. When it is detected by the metal detector 6 that the leading end of the rolled material has reached the last rolling mill 1f of the intermediate rolling mill row 1, the water cooling control device 10 changes the leading end of the rolled material to the intermediate water cooling zone from this detection time. Time is calculated until it reaches, and from this arrival time, the temperature T1 in the longitudinal direction of the rolled material on the entry side of the intermediate water cooling zone 3 is measured by the entry side thermometer 4 at predetermined time intervals. And this temperature measurement value T1 is matched with the site | part of the longitudinal direction of a rolling material, and it is taken in into the water cooling control apparatus 10 as mentioned above. Next, when it is detected by the metal detector 7 that the leading end of the rolled material has reached the leading rolling mill 2a of the finish rolling mill row 2, the command from the water cooling control device 10 outputs the leading rolling mill 2a. The temperature T2 in the longitudinal direction of the rolled material measured at the predetermined time interval, that is, the temperature T2 in the longitudinal direction of the rolled material is measured by the side thermometer 5 at a predetermined time interval. Is done. In accordance with the difference ΔT2 between the detected temperature T2 and the target temperature T2a at the position of the leading rolling mill 2a outlet thermometer 5 set in advance, that is, the temperature T2 of the rolled material is matched with the target temperature T2a. Feedback control is performed on the flow rate of the cooling water in the intermediate water cooling zone 3 for the rolled material. For the next rolled material, the set amount of the cooling water flow rate and / or the rolling speed is controlled.

  In the control of the cooling water flow rate for the rolled material, the cooling water flow rate Wa in the water cooling zone is corrected by the cooling water flow rate ΔWa necessary for eliminating the temperature deviation ΔT2 with respect to the difference ΔT2 from the target temperature T2a. The measured temperature T2 on the outlet side of the leading rolling mill 2a that compares the temperature deviation with the target temperature T2a is an average value obtained by averaging a plurality of measured temperatures in the longitudinal direction of the rolled material in consideration of variations in temperature measurement ( T2av.). Therefore, ΔT2 = ABS (T2a−T2) = ABS (T2a−T2av.). ABS is a symbol representing an absolute value. Similarly, an average value (T1av.) Of a plurality of measured temperatures in the longitudinal direction of the rolled material is used as the temperature T1 in the longitudinal direction of the rolled material on the intermediate water cooling zone 3 entrance side. The averaging of the measured temperatures on the outlet side of the leading rolling mill 2a and the inlet side of the intermediate water cooling zone 3 is repeated for the temperature measurement region group along the longitudinal direction of the rolled material. And from the average temperature T1av on the entry side of the intermediate water cooling zone 3, the average temperature T2av on the exit side of the leading rolling mill 2a, the temperature drop (T1av.-T2av), and the target temperature T2a on the exit side of the leading rolling mill 2a Temperature deviation ΔT 2, cooling water flow rate Wa (average flow rate) when the measurement part where the average temperature is calculated passes through the intermediate water cooling zone 3, correction flow rate ΔWa (average flow rate) based on the temperature deviation ΔT 2, and the rolling material The target temperature T1a, the target temperature drop amount (T1a-T2a), the rolling speed, the product size (finished wire diameter) of the rolled material, and the steel type of the intermediate water cooling zone 3 with respect to the storage section (not shown) ). And, including the next rolled material of the same lot, the initial set flow rate Wp and the target temperature of the intermediate water cooling zone 3 based on the stored water cooling control results for the rolled material of the same steel type or the same steel type group and the same product size. The correction flow rate ΔWu per 1 ° C. deviation from T2a is corrected to improve the water cooling control accuracy. The initial set flow rate Wp of the cooling water is a water cooling control performance value for rolling conditions such as steel grade, product dimensions, rolling speed, etc. with respect to the target temperature drop (T1a-T2a) in the intermediate water cooling zone 3. It can be determined based on the cooling water flow rate obtained in advance from the above. Further, the corrected flow rate ΔWu per 1 ° C. from the target temperature T2a is based on the deviation between the average value ΔWam of the corrected flow rate ΔWa for the rolled material and the average temperature T2m of T2 for the rolled material and the target temperature T2a. It is possible to calculate.

  The temperature of the rolled material usually varies over the entire length of the front and rear end portions and the intermediate portion in one rolled material due to the heating state in the heating furnace and the like, and also varies between the rolled materials. For this reason, in order to operate the cooling water flow rate adjusting valve accurately and in a timely manner by the control command from the water cooling control device 10 based on the deviation from the target temperature, the operation of the flow rate adjusting valve is delayed. In consideration of the above, the correction flow rate ΔWa of the cooling water with respect to the temperature deviation ΔT2 from the target temperature T2a is set at an early timing relative to the next rolling material, that is, the leading end of the next rolling material reaches the intermediate water cooling zone 3. At the time, it is desirable to give an operation instruction of the valve opening degree so that the opening degree of the flow rate control valve becomes the valve opening degree of the initial setting flow rate (= Wp + ΔWp (= ΔWa)) incorporating the correction flow rate ΔWa.

  FIG. 2 shows the main part of the steel bar or wire rod rolling facility as in the case of FIG. 1. In this embodiment, the first rolling mill 2a of the finishing rolling mill row 2 downstream of the intermediate water cooling zone 3 is shown in FIG. Instead of providing the thermometer 5 on the delivery side (see FIG. 1), a rolling load detector is attached to the leading rolling mill 2a as the rolling load detector 12, and the other equipment configuration is the same as in FIG. Since it is the same, description is abbreviate | omitted.

  From the point of time when the rolled material 11 reaches the intermediate rolling mill row 1, the water cooling control device 10 performs detailed tracking of the rolled material 11. Whether or not the rolled material 11 has reached the last rolling mill 1f of the intermediate rolling mill row 1 is detected by the metal-in detector 6. And, from the predetermined pass schedule of the rolled material, the rolling speed detected by the linear velocity detector 8, and the temperature measurement value of the rolled material by the entry side thermometer (entrance side temperature detector) 4, an intermediate A portion in the longitudinal direction of the rolled material, the temperature, and the rolling speed when passing through the water cooling zone 3 are associated with each other, and these values are linked and taken into the water cooling control device 10. When it is detected by the metal detector 6 that the leading end of the rolled material has reached the last rolling mill 1f of the intermediate rolling mill row 1, the water cooling control device 10 causes the leading end of the rolled material 11 to move to the intermediate water cooling zone from this detection time. Time is calculated until it reaches 3, and from this arrival time, the temperature T1 in the longitudinal direction of the rolling material on the inlet side of the intermediate water cooling zone 3 is measured by the inlet side thermometer 4 at predetermined time intervals. And this temperature measurement value T1 is taken into the water-cooling control apparatus 10 corresponding to the site | part of the longitudinal direction of a rolling material as mentioned above. Next, when it is detected by the metal detector 7 that the leading end of the rolled material 11 has reached the leading rolling mill 2a of the finish rolling mill row 2, the rolling load detector is detected by a command from the water cooling control device 10. 12, the rolling load F of the rolling load is measured at a predetermined time interval in the longitudinal direction of the rolled material, that is, at a portion corresponding to the longitudinal portion of the rolled material 11 measured at the entrance side of the intermediate water cooling zone 3. . Depending on the difference ΔF between the measured rolling load F and a preset target rolling load Fa, that is, for the rolled material, the cooling water in the intermediate water cooling zone 3 is used so that the measured load matches the target load. Feedback control of the flow rate. For the next rolled material, the set value (preset value) of the cooling water flow rate and / or the rolling speed is adjusted.

  The control of the cooling water flow rate for the rolled material corrects the cooling water flow rate Wa in the water cooling zone by the cooling water flow rate ΔWa corresponding to ΔF with respect to the difference ΔF from the target rolling load Fa. The rolling load F of the leading mill 2a for comparing the difference with the target rolling load Fa is an average value (Fav.) Of a plurality of measured rolling loads in the longitudinal direction of the rolled material in consideration of variations in the measured rolling load. It is. Therefore, ΔF = ABS (Fa−F) = ABS (Fa−Fav.). Similarly, an average value (T1av.) Of a plurality of measured temperatures in the longitudinal direction of the rolling material corresponding to the rolling load measurement site of the leading rolling mill 2a is used as the temperature T1 in the longitudinal direction of the rolled material on the entry side of the intermediate cooling zone 1. It is done. The averaging of the measured rolling load F of the first rolling mill 2a and the measured temperature T1 on the entry side of the intermediate rolling mill row 1 is repeated for the rolling load and temperature measurement part group along the longitudinal direction of the rolled material. And the average temperature T1av. The average rolling load Fav. Of the leading rolling mill 2a, the load deviation ΔF from the target rolling load Fa, the average temperature T1av. The measured water flow rate Wa (average flow rate), correction flow rate ΔWa (average flow rate), and rolling speed, product dimensions (finished wire diameter) of the rolled material, and steel type It is stored in a storage unit (not shown) of the water cooling control device 10. And, including the next rolled material of the same lot, the initial set flow rate Wp and the target of the intermediate water cooling zone 3 based on the stored water cooling control result for the rolled material of the same steel type or the same steel type group and the same product size. The correction flow rate ΔWu per unit rolling load deviating from the rolling load Fa is corrected to improve the water cooling control accuracy. In addition, the initial setting flow rate Wp of the cooling water is determined with respect to the inlet side temperature T1av. Of the intermediate water cooling zone 3 and the target rolling load Fa of the leading rolling mill 2a for each rolling condition such as a steel type, a product size, and a rolling speed. Further, it can be determined based on the cooling water flow rate obtained in advance from the water cooling control result value or the like. Further, the correction flow rate ΔWu per deviation unit rolling load from the target temperature is a deviation between the average value ΔWam of the correction flow rate ΔWa for the rolled material, and the target rolling load Fa and the average load Fm of the rolling load F for the rolling material. It is possible to calculate based on

  Similar to the above-described embodiment in which the temperature of the rolling material on the outlet side of the leading rolling mill 2a is measured, the deviation from the target rolling load also occurs in the above-described embodiment in which the rolling load of the leading rolling mill 2a is measured. Based on the control command from the water cooling control device 10, based on the target rolling load F2a in consideration of the fact that the operation of the flow rate adjusting valve is delayed in order to operate the cooling water flow rate adjusting valve accurately and in a timely manner. The correction flow rate ΔWa of the cooling water with respect to the load deviation ΔF of the next rolling material is opened at an early timing, that is, when the leading end of the next rolling material reaches the intermediate water cooling zone 3, the flow control valve is opened. It is desirable to give an operation instruction of the valve opening so that the degree becomes the valve opening of the initial set flow (= Wp + ΔWp (= ΔWa)) incorporating the correction flow ΔWa.

  In addition, in said embodiment, although the form which uses the rolling load F as a rolling load was shown, the load current I of the electric motor which drives a rolling roll can be used as a rolling load. In addition, even when either a rolling load or a load current is used as the rolling load, if the rolling speed is changed, the rolling load changes even if the temperature of the rolled material is the same. Therefore, the target rolling load Fa or the target load current is changed. It is desirable that Ia can be corrected by the rolling speed. Further, the measured temperature on the outlet side of the leading rolling mill 2a and the measured rolling load of the leading rolling mill 2a are subjected to feedforward control based on the deviation between the rolling material temperature on the inlet side of the intermediate water cooling zone 3 and the target temperature. It can also be used when performing.

It is explanatory drawing which shows the principal part of the layout of the steel bar / wire rod rolling equipment which performs water cooling control of embodiment. It is explanatory drawing which shows the principal part of the layout of the steel bar / wire rod rolling equipment which performs water cooling control of other embodiment. It is explanatory drawing which shows the temperature transition of the rolling material in an intermediate | middle water cooling process and a recuperation process.

Explanation of symbols

1: Intermediate rolling mill row 1a to 1f: Rolling mill 2: Finish rolling mill row 2a to 2f: Rolling mill 3: Intermediate water cooling zone 4: Incoming thermometer 5: Outgoing thermometer 6, 7: Metal-in (biting in) ) Detectors 8 and 9: Linear velocity detector 10: Water cooling controller 11: Rolled material 12: Rolling load detector 13: Finishing thermometer

Claims (4)

  A plurality of rolling mill rows are formed by rolling mills arranged in multiple stages continuously, and a water cooling device having a water cooling control means having a cooling water flow rate adjusting means is arranged between the upstream and downstream rolling mill rows. A method for controlling water cooling of a rolled material in a steel bar or wire rolling facility, wherein after the water cooling by the water cooling control means, the surface temperature of the rolled material on the outlet side of the first rolling mill in the downstream rolling mill row A method for controlling water cooling of a rolled material, wherein the flow rate of cooling water supplied to the water cooling device is controlled so that the temperature becomes a predetermined temperature.   A plurality of rolling mill rows are formed by rolling mills arranged in multiple stages continuously, and a water cooling device having a water cooling control means having a cooling water flow rate adjusting means is arranged between the upstream and downstream rolling mill rows. A method of controlling water cooling of a rolled material in a steel bar or wire rod rolling facility, wherein the water cooling control means performs water cooling of the rolled material with the water cooling device and then rolling on the outlet side of the first rolling mill in the downstream rolling mill row Based on the deviation between the material surface temperature and the preset target surface temperature, the set value of the cooling water supply flow rate and / or rolling speed to the water cooling device is adjusted for the next rolled material. Water cooling control method.   A plurality of rolling mill rows are formed by rolling mills arranged in multiple stages continuously, and a water cooling device having a water cooling control means having a cooling water flow rate adjusting means is arranged between the upstream and downstream rolling mill rows. A method for controlling water cooling of a rolled material in a steel bar or wire rod rolling facility, wherein after the water cooled by the water cooling device by the water cooling control means, the rolling load in the first rolling mill in the downstream rolling mill row is reduced. A method for controlling water cooling of a rolled material, wherein the flow rate of cooling water supplied to the water cooling device is controlled so as to achieve a predetermined rolling load.   A plurality of rolling mill rows are formed by rolling mills arranged in multiple stages continuously, and a water cooling device having a water cooling control means having a cooling water flow rate adjusting means is arranged between the upstream and downstream rolling mill rows. A method for controlling water cooling of a rolled material in a steel bar or wire rolling facility, wherein after the water cooled by the water cooling device by the water cooling control means, the rolling load of the first rolling mill in the downstream rolling mill row and A rolling material water cooling control method, comprising: adjusting a cooling water supply flow rate to the water cooling device and / or a setting value of a rolling speed for a next rolled material based on a deviation from a set target rolling load.

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