A method for controlling the coiling temperature in a continuous rolling process

Abstract

The embodiment of the application provides a headless rolling coiling temperature control method, relates to the technical field of hot-rolled strip production, and the method comprises the following steps: confirming the opening state of a cooling header for cooling a strip; dividing each coil of the strip into multiple sample sections in the length direction, wherein the multiple sample sections comprise a closed sample section at the front end of the strip; taking the opening state of the current cooling header as an adjustment basis, adjusting a feedforward header when a sample section of the strip passes through a finishing mill outlet pyrometer, and judging whether a speed control header needs to be adjusted based on the speed change of the sample section of the strip; if yes, determining the critical position of the speed control header and adjusting the speed control header; and obtaining the measured temperature of a coiling pyrometer after the closed sample section of the strip passes through the coiling pyrometer, and adjusting a feedback header. The method can guarantee that the coiling temperature is stably controlled in a control interval, improves the coiling temperature hit rate, and promotes the full-length performance consistency of the strip.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hot strip production, in particular to a method for controlling coiling temperature in endless rolling. BACKGROUND

[0002] The thin slab continuous casting and rolling technology has rapidly developed in China due to its technical advantages of continuity, low cost and high efficiency in thin material production. In endless rolling, the multi-mode continuous casting and rolling production line (referred to as MCCR) initiates the multi-mode continuous casting and rolling form, realizes the multi-mode casting and rolling form of single piece, semi-endless and full-endless switching, and greatly improves the production rhythm and product yield. In the thin slab continuous casting and rolling production process, the control precision of laminar cooling is closely related to the final product performance of the strip. After the strip passes through the last stand of the finishing mill, it enters the laminar cooling output roller. The laminar cooling zone includes a plurality of cooling sections, each of which is configured with a plurality of upper and lower water spray headers. The cooling header valves to be opened are calculated by a laminar cooling control model. The strip is cooled by the laminar cooling water of the cooling header, and the target coiling temperature control is realized before reaching the coiler.

[0003] In the endless rolling mode, the strip continuously rolled in the same rolling period is divided into different virtual coils according to the coiling and cutting coil, and the secondary process control model and the primary basic automatic control are performed. Unlike the traditional hot continuous rolling, there is no threading, speed-up and speed-down stage, and tail throwing stage in the rolling of each coil of strip in the endless rolling mode, and the strip is continuously rolled in the whole rolling period. In the case where the product specification does not change much, the change of the opening state of the cooling header between different virtual coils causes the fluctuation of the coiling temperature, which finally affects the performance consistency of the strip in the full length direction. In addition, in the endless rolling mode, the strip running speed is limited by the casting speed, the thickness difference between coils, and other factors, and is often accompanied by thickness fluctuation, dynamic specification change, etc. The strip running speed affects the time through the laminar cooling zone, thereby finally affecting the coiling temperature control precision. SUMMARY

[0004] The embodiment of the present application provides a method for controlling coiling temperature in endless rolling. The method inherits the opening state of the cooling header and sets the speed control header, eliminates the coiling temperature fluctuation caused by the sudden change of the opening state of the cooling header at the connection between two coils in the endless rolling mode without FGC, suppresses the problem of unstable coiling temperature caused by the fluctuation of the strip running speed, and improves the coiling temperature hit rate of the strip in the full length.

[0005] Other characteristics and advantages of the present application will become apparent from the following detailed description, or will be learned by practice of the present application.

[0006] According to a first aspect of the embodiment of the present application, a method for controlling coiling temperature in endless rolling is provided, comprising:

[0007] Confirm the opening state of the cooling header for cooling the strip steel, the cooling header comprising a feedforward header, a speed control header and a feedback header;

[0008] Divide each coil of strip steel into a plurality of sample sections in the length direction, the plurality of sample sections comprising a closed sample section at the front end of the strip steel;

[0009] Adjust the feedforward header based on the opening state of the current cooling header, and determine whether the speed control header needs to be adjusted based on the speed change of the strip sample section after the strip sample section passes through the finishing mill outlet pyrometer, and if so, determine the critical position of the speed control header and adjust the speed control header;

[0010] After the closed sample section passes through the coiling pyrometer, obtain the measured temperature of the coiling pyrometer, and adjust the feedback header.

[0011] In some embodiments of the present application, based on the foregoing scheme, the confirmation of the opening state of the cooling header for cooling the strip steel comprises:

[0012] Determine whether the two adjacent coils of strip steel are the same grade of strip steel based on the grade, thickness and target coiling temperature of the strip steel, and if so, the opening state of the cooling header of the previous strip steel is used for the subsequent strip steel, otherwise the opening state of the cooling header of the subsequent strip steel is reconfirmed.

[0013] In some embodiments of the present application, based on the foregoing scheme, the adjustment of the feedforward header comprises:

[0014] The finishing mill outlet pyrometer measures the measured temperature of the current strip sample section;

[0015] Based on the measured temperature measured by the finishing mill outlet pyrometer, adjust the opening state of the feedforward header based on the opening state of the current cooling header.

[0016] In some embodiments of the present application, based on the foregoing scheme, the method further comprises: after the strip sample section passes through the finishing mill outlet pyrometer, correcting the current TVD curve according to the measured speed of the strip sample section.

[0017] In some embodiments of the present application, based on the foregoing scheme, the determination of whether the speed control header needs to be adjusted based on the speed change of the strip sample section comprises:

[0018] Call a speed change determination function to determine the speed change of the current strip sample section, comprising:

[0019] Calculate the speed V1 of the current strip sample section when it reaches the speed control header;

[0020] Compare the speed V1 with the predicted speed V2 of the strip sample section after passing through the finishing mill outlet pyrometer, and if adjusting an open state of the speed control header, wherein C is a configurable constant.

[0021] In some embodiments of the present application, based on the foregoing scheme, the determining the critical position of the speed control header comprises:

[0022] calculating a delay distance of the speed control header based on the speed of the current strip sample section and a water valve delay response time of the speed control header;

[0023] determining the critical position of the speed control header based on the delay distance and a position of the speed control header.

[0024] In some embodiments of the present application, based on the foregoing scheme, the adjusting the speed control header comprises:

[0025] predicting a temperature distribution of the strip between the speed control header and the coiling pyrometer to obtain a speed control predicted coiling temperature of the current strip sample section;

[0026] adjusting the open state of the speed control header based on a temperature difference between the speed control predicted coiling temperature and a target coiling temperature on the basis of the current open state of the speed control header.

[0027] In some embodiments of the present application, based on the foregoing scheme, the adjusting the feedback header comprises:

[0028] obtaining a first feedback predicted coiling temperature of the current strip sample section and a second feedback predicted coiling temperature of the strip sample section reaching the coiling pyrometer at this time;

[0029] adjusting the open state of the feedback header based on a temperature difference between a measured temperature of the coiling pyrometer and the target coiling temperature and a temperature difference between the first feedback predicted coiling temperature and the second feedback predicted coiling temperature on the basis of the current open state of the feedback header.

[0030] In some embodiments of the present application, based on the foregoing scheme, the finishing outlet pyrometer is an optical pyrometer or a radiation pyrometer.

[0031] In some embodiments of the present application, based on the foregoing scheme, the coiling pyrometer is an optical pyrometer or a radiation pyrometer.

[0032] The technical scheme of the present application provides a coiling temperature control method for the thin slab continuous casting and rolling endless rolling mode, guarantees the coiling temperature to be stably in a control interval, improves the coiling temperature hit rate, and promotes the full-length performance consistency of the strip.

[0033] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF DRAWINGS

[0034] The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate embodiments consistent with the present application and, together with the description, further serve to explain the principles of the application. It is to be understood that the drawings are designed solely for purposes of illustration to be used in conjunction with the description in

[0035] Figure 1 Fig. 1 shows a flow diagram of a method for controlling the coiling temperature of a headless rolling according to an embodiment of the present application;

[0036] Figure 2 Fig. 2 shows a diagram of the change in the coiling temperature of a 1# strip and a 2# strip according to an embodiment of the present application with the opening state of the cooling header;

[0037] Figure 3 Fig. 3 shows a diagram of the change in the coiling temperature of a 3# strip and a 4# strip according to an embodiment of the present application with the opening state of the cooling header;

[0038] Figure 4 Fig. 5 shows a diagram of the change in the speed of a 5# strip according to an embodiment of the present application;

[0039] Figure 5 Fig. 6 shows a diagram of the change in the coiling temperature of a 5# strip according to an embodiment of the present application with the opening state of the cooling header;

[0040] Figure 6 Fig. 7 shows a diagram of the relationship between the speed of a 6# strip and the number of open control headers according to an embodiment of the present application;

[0041] Figure 7 Fig. 8 shows a diagram of the change in the coiling temperature of a 6# strip according to an embodiment of the present application with the opening state of the cooling header. DETAILED DESCRIPTION

[0042] Example implementations will now be described more fully with reference to the accompanying drawings. Example implementations may, however, be implemented in many different forms and should not be construed as limited to the implementations set forth herein; rather, these implementations are provided so that this disclosure will be thorough and complete, and will fully convey the scope of example implementations to those skilled in the art. Like reference numerals refer to like elements throughout.

[0043] Moreover, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the application. One skilled in the relevant art will recognize, however, that the application can be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, devices, implementations, and operations have not been shown or described in detail to avoid obscuring aspects of the application.

[0044] The flowcharts shown in the drawings are only illustrative, and do not necessarily include all contents and operations / steps, nor are they necessarily executed in the order described. For example, some operations / steps can be further decomposed, and some operations / steps can be combined or partially combined, so the actual execution order can be changed according to actual conditions.

[0045] It should be noted that "a plurality of" as referred to herein means two or more.

[0046] To make the objectives, technical solutions, and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0047] Some embodiments of the present application will be described in detail below with reference to the drawings. The following embodiments and features in the embodiments can be combined with each other without conflict.

[0048] Referring to Figure 1 , a flowchart of a method for controlling the temperature of a continuous rolling and coiling according to an embodiment of the present application is shown.

[0049] As shown in Figure 1 , the present embodiment provides a method for controlling the temperature of a continuous rolling and coiling, which specifically includes steps S100 to S600.

[0050] Step S100: Confirm the opening state of a cooling header for cooling the strip, the cooling header including a feedforward header, a speed control header, and a feedback header.

[0051] It should be noted that the opening state of the cooling header is different for different incoming material states and different coiling temperatures, so in the present embodiment, the opening state of the cooling header corresponding to each coil of strip needs to be confirmed.

[0052] It can be understood that the cooling header in the embodiment refers to a header for outputting cooling water when the strip steel passes through the finishing mill train after rolling and enters the laminar cooling area. The cooling header includes a feedforward header, a speed control header, and a feedback header, which are in the order of feedforward header-speed control header-feedback header according to the cooling sequence of the strip steel.

[0053] For example, the cooling header has X groups in total, wherein the feedforward header has m groups, the speed control header has n groups, and the feedback header has y groups, and X = m + n + y; when the strip steel enters the laminar cooling area, it first passes through the feedforward header, then passes through the speed control header, and finally passes through the feedback header.

[0054] In some possible embodiments, the confirmation of the opening state of the cooling header for cooling the strip steel specifically includes:

[0055] Based on the steel grade, thickness, and target coiling temperature of the strip steel, it is determined whether the two adjacent coiled strip steels are strip steels of the same layer, if they are strip steels of the same layer, the opening state of the cooling header of the previous strip steel is used for the subsequent strip steel, otherwise, the opening state of the cooling header of the subsequent strip steel is reconfirmed.

[0056] By using the cooling header, the problem of coiling temperature fluctuation at the joint of the two adjacent coiled strip steels caused by the change of the opening state of the cooling header can be well solved.

[0057] It can be understood that in the embodiment, the steel grade, thickness, and target coiling temperature of the strip steel need to be compared to determine whether the two adjacent coiled strip steels are of the same layer.

[0058] It should be noted that the target coiling temperature is a temperature value set for the coiling temperature of all sample sections of each coiled strip steel.

[0059] For example, the strip steel A and the strip steel B are two adjacent coiled strip steels, the steel grade of the strip steel A is Q195 steel, the thickness is α, and the corresponding thickness layer is a (the corresponding thickness range is [g i ,g i+1 ), and the target coiling temperature is β, and the corresponding temperature layer is b (the corresponding temperature range is [T j ,T j+1 ]); when determining whether the strip steel B is a strip steel of the same layer as the strip steel A, it is necessary to determine whether the strip steel B is Q195 steel, whether the thickness of the strip steel B is within the range of [g i ,g i+1 ], and whether the temperature is within the range of [T j ,T j+1 ]; only when the strip steel B is Q195 steel, the thickness layer of the strip steel B is a, and the temperature layer is b, the strip steel B belongs to the same layer as the strip steel A.

[0060] It should be noted that the two adjacent strip coils in the embodiment refer to two strip coils entering the laminar cooling area in sequence according to the order after being rolled by the finishing rolling mill.

[0061] With reference to the foregoing Figure 1 , step S200, each strip coil is divided into a plurality of sample sections in the length direction, and the plurality of sample sections include a closed sample section at the front end of the strip coil.

[0062] It should be noted that when the closed sample section at the front end of the strip coil passes through the feedback header, the feedback header is not adjusted, and the closed sample section at the front end of the strip coil is mainly used to measure the actual temperature of the winding pyrometer, and when the sample section behind the closed sample section passes through the feedback header, the feedback header can be adjusted according to the actual temperature obtained by the winding pyrometer.

[0063] With reference to the foregoing Figure 1 , step S300, based on the opening state of the current cooling header, the feedforward header is adjusted when the sample section of the strip coil passes through the finishing rolling mill outlet pyrometer.

[0064] It can be understood that when new strip steel enters the laminar cooling area from the finishing rolling mill outlet, the feedforward header needs to be used for cooling, and the current cooling header (including the feedforward header, the speed control header, and the feedback header) maintains the opening state when the previous strip coil is cooled. Therefore, in this step, the opening state of the feedforward header needs to be adjusted based on the opening state of the current cooling header to adapt to the current strip coil.

[0065] It should be noted that the opening state of the cooling header in the embodiment includes the opening state of the feedforward header, the opening state of the speed control header, and the opening state of the feedback header. In the subsequent steps, the feedforward header, the speed control header, and the feedback header are adjusted based on the opening state of the current feedforward header, the opening state of the speed control header, and the opening state of the feedback header. The opening state in the embodiment specifically refers to the number of open valves of the cooling header. Therefore, the adjustment of the feedforward header in the embodiment specifically refers to the adjustment of the number of open valves of the feedforward header.

[0066] In some possible embodiments, the adjustment of the feedforward header specifically includes steps S310 to S320.

[0067] Step S310, the finishing rolling mill outlet pyrometer measures the actual temperature of the current sample section of the strip coil.

[0068] Step S320, based on the opening state of the current cooling header, the opening state of the feedforward header is adjusted according to the actual temperature measured by the finishing rolling mill outlet pyrometer.

[0069] It can be understood that when the measured temperature detected by the finishing outlet pyrometer is higher than the preset value, some of the feedforward header valves are opened; if it is lower, some of the feedforward header valves are closed accordingly. The specific temperature preset value is determined according to the actual situation on site.

[0070] In some possible embodiments, the finishing outlet pyrometer is an optical pyrometer or a radiation pyrometer.

[0071] The optical pyrometer is a non-contact high-temperature measuring instrument. When the measured temperature is higher than the range that can be used by a thermocouple, and a thermocouple cannot be installed or is not suitable to be installed, the optical pyrometer can generally meet the requirement. It is widely used to measure the temperature in smelting, casting, rolling, glass melting, forging, heat treatment, etc., and is one of the indispensable temperature measuring instruments in the production processes of metallurgy, chemical industry and machinery.

[0072] The radiation pyrometer is designed and manufactured according to the functional relationship between the radiation energy of an object in the entire wavelength range and the temperature thereof. It uses a radiation temperature sensor as a primary instrument and an electronic potential difference meter as a secondary instrument. It belongs to a lens focusing type temperature sensor, has an aluminum alloy shell, the front part is an objective lens, the shell body is provided with a thermocouple compensation light barrier, and there is a tuning plate on the field light barrier close to the thermocouple. The function of the tuning plate is to adjust the radiation energy irradiated to the thermocouple, so that the product has a unified graduation value. The detachable rear cover plate is provided with an eyepiece, so as to observe the image of the measured object.

[0073] With reference back to Figure 1 , in step S400, when the strip sample section passes through the finishing outlet pyrometer, the current TVD curve is corrected according to the measured speed of the strip sample section.

[0074] It can be understood that the TVD curve in the embodiment refers to a time-velocity-distance curve, and the measured speed of the strip sample section can be measured by a special speed measuring instrument such as a speed measuring instrument.

[0075] With reference back to Figure 1 , in step S500, it is judged whether the speed control header needs to be adjusted based on the speed change of the strip sample section. If yes, the critical position of the speed control header is determined, and the speed control header is adjusted.

[0076] In some possible embodiments, the judgment of whether the speed control header needs to be adjusted based on the speed change of the strip sample section specifically includes step S510.

[0077] In step S510, a speed change judgment function is called to judge the speed change of the current strip sample section, including:

[0078] The speed V1 of the current strip sample section when it reaches the speed control header is calculated.

[0079] Comparing the speed V1 with a predicted speed V2 of the strip sample section after the exit high-temperature gauge of the finishing mill, if adjusting the opening state of the speed control header, wherein C is a configurable constant.

[0080] It can be understood that the constant C is determined according to specific conditions, and in general, the value range of C is 0-0.4.

[0081] It should be noted that in the embodiment, the predicted speed V2 is calculated according to the TVD curve.

[0082] In some possible embodiments, the determining the critical position of the speed control header specifically includes steps S520 to S530.

[0083] In step S520, a delay distance of the speed control header is calculated based on the speed of the current strip sample section and the water valve delay response time of the speed control header, specifically: delay distance = strip sample section speed * water valve delay response time.

[0084] In step S530, the critical position of the speed control header is determined based on the delay distance and the position of the speed control header, specifically: critical position of the speed control header = position of the speed control header + delay distance.

[0085] It can be understood that the position of the speed control header refers to the position of the speed control header in the cooling header. For example, referring to the foregoing example, the position of the speed control header refers to the position of the first speed control header in the X group of cooling headers.

[0086] In some possible embodiments, the adjusting the speed control header specifically includes steps S540 to S550.

[0087] In step S540, the temperature distribution of the strip between the speed control header and the coiling high-temperature gauge is predicted, and a speed control predicted coiling temperature of the current strip sample section is obtained.

[0088] It should be noted that the speed control predicted coiling temperature in the embodiment refers to the predicted temperature obtained by predicting the temperature distribution of the strip between the speed control header and the coiling high-temperature gauge when the strip sample section reaches the speed control header.

[0089] It can be understood that when the speed control predicted coiling temperature is obtained, the current strip sample section is at the speed control header, and therefore, the temperature distribution of the strip between the speed control header and the coiling high-temperature gauge needs to be predicted.

[0090] In step S550, based on the opening state of the current speed control header, the opening state of the speed control header is adjusted according to the temperature difference between the speed control predicted coiling temperature and the target coiling temperature.

[0091] It can be understood that, in the embodiment, the speed control header valve is opened or closed according to the size of the temperature difference, so as to adjust the temperature and ensure that the temperature difference meets the set value. The specific adjustment is determined according to the actual situation.

[0092] In some possible embodiments, the coiling pyrometer is an optical pyrometer or a radiation pyrometer.

[0093] The optical pyrometer and the radiation pyrometer are common pyrometers, and both are very suitable for measuring the temperature of the strip steel.

[0094] Continuing to refer to Figure 1 , step S600, after the closed sample section of the strip steel passes through the coiling pyrometer, the measured temperature of the coiling pyrometer is obtained, and the feedback header is adjusted.

[0095] It should be noted that the closed sample section of the strip steel passes through the feedback header first, and then passes through the coiling pyrometer. The feedback header is not adjusted when each closed sample section of the strip steel passes through the feedback header, because the feedback header needs to be adjusted after the measured temperature of the coiling pyrometer is obtained, and since the closed sample section is at the front end of the strip steel, when it passes through the feedback header, the strip steel sample section has not reached the coiling pyrometer.

[0096] For example, the closed sample section is n, when the strip steel sample section n+1 passes through the feedback header, the coiling pyrometer has strip steel passing through, the measured temperature is measured, and then the feedback header can be adjusted according to the measured temperature. For the first n sample sections, when they pass through the feedback header, the current strip steel may not have reached the coiling pyrometer, and there is no measured coiling temperature, so no feedback adjustment is performed.

[0097] In some possible embodiments, the adjusting the feedback header specifically includes steps S610 to S620.

[0098] Step S610, obtaining a first feedback predicted coiling temperature of the current strip steel sample section, and a second feedback predicted coiling temperature of the strip steel sample section that reaches the coiling pyrometer at this time.

[0099] It should be noted that the process of obtaining the feedback predicted coiling temperature is as follows:

[0100] When the strip steel sample section reaches the feedback header, the temperature distribution of the strip steel between the feedback header and the coiling pyrometer at this time is predicted, and the feedback predicted coiling temperature of the strip steel sample section is obtained.

[0101] It should be noted that the feedback predicted coiling temperature in the embodiment refers to the predicted temperature obtained by predicting the temperature distribution of the strip steel between the feedback header and the coiling pyrometer at this time when the strip steel sample section reaches the feedback header.

[0102] For example, at the same moment, the strip sample segment n is at the feedback manifold, and the strip sample segment m is at the coiling pyrometer; the strip sample segment m is cooled before the strip sample segment n, and when the strip sample segment m arrives at the feedback manifold, the temperature distribution of the strip between the feedback manifold and the coiling pyrometer is predicted to obtain the second predicted coiling temperature; when the strip sample segment n arrives at the feedback manifold, the temperature distribution of the strip between the feedback manifold and the coiling pyrometer is predicted to obtain the first predicted coiling temperature.

[0103] Step S620: Based on the current feedback manifold opening state, the feedback manifold opening state is adjusted according to the temperature difference between the actual temperature measured by the coiling pyrometer and the target coiling temperature, and the temperature difference between the first feedback predicted coiling temperature and the second feedback predicted coiling temperature.

[0104] It should be noted that the coiling temperature actually measured by the current coiling pyrometer refers to the temperature of the strip sample section measured by the current coiling pyrometer. The strip sample section measured at this time is the sample section that has passed through the speed control manifold and the feedback manifold. It may belong to the same strip as the current strip sample section, or it may belong to the previous strip. If the coiling temperature is not measured on the coiling pyrometer, the feedback manifold will not be adjusted at this time.

[0105] It can be understood that, in this embodiment, the feedback header valve is opened or closed according to the size of the temperature difference, and the specific adjustment is determined according to actual needs.

[0106] Below, a specific implementation example is provided.

[0107] Taking the rolling of a certain steel grade SMZG as an example, the finished strip thickness in the headless rolling mode is in the range of 1.0-3.5mm, and the coiling target temperature is 550-580℃. Starting from the second coil of headless rolling, the opening state of the cooling manifold is determined when the strip head reaches the F1 stand with load; after reaching the pyrometer at the finishing rolling exit, the feedforward manifold valve is adjusted according to the measured temperature at the pyrometer at the finishing rolling exit. At the same time, a function is called to determine the speed fluctuation to meet the requirements. The speed control manifold is adjusted when conditions permit, and the critical position for opening the speed control manifold is calculated. When the closed sample section reaches the coiling pyrometer, the feedback manifold adjustment is triggered. Based on the predicted coiling temperature of the previous sample section under the feedforward + speed control manifold cooling and the current coiling temperature measured by the coiling pyrometer, combined with the number of feedback manifold valve openings in the previous sample section, the feedback manifold valve of the current sample section is adjusted.

[0108] Before the optimization method is adopted, the change of coiling temperature of two adjacent strips (1# and 2#) with the opening state of the cooling header is as follows: Figure 2Fig. 4 shows the change of the coiling temperature of the adjacent two strips (3# and 4#) with the opening state of the cooling header after the optimization of the method; Figure 3 As shown in Fig. 4, the opening state of the cooling header of the strip head sample section is inherited from the opening state of the cooling header of the strip tail sample section, and the coiling temperature of the adjacent strips at the transition is kept stable.

[0109] Referring to Fig. 5, Figures 4 to 7 As shown in Fig. 5, the 5# strip is not provided with a speed control header, and the 6# strip is provided with a speed control header. It can be seen from the figure that by setting the speed control header, the fluctuation of the coiling temperature with the change of the speed is inhibited.

[0110] Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments disclosed herein. Variations and modifications of the embodiments disclosed herein can be made based on the description set forth herein, without departing from the scope and spirit of the application. Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.

Claims

1. A method of controlling the temperature of a headless roll, characterized by, The application relates to a method for adjusting the opening state of cooling headers for cooling a strip steel, and belongs to the technical field of strip steel cooling. The method comprises the following steps: confirming the opening state of the cooling headers for cooling the strip steel, wherein the cooling headers sequentially comprise a feedforward header, a speed control header and a feedback header; dividing each coil of the strip steel into multiple sample sections in the length direction, wherein the multiple sample sections comprise a closed sample section at the front end of the strip steel; adjusting the feedforward header based on the opening state of the current cooling header, when the strip steel sample section passes through a finishing mill outlet pyrometer, and judging whether the speed control header needs to be adjusted based on the speed change of the strip steel sample section, if yes, determining the critical position of the speed control header, and adjusting the speed control header; after the closed sample section of the strip steel passes through a coiling pyrometer, obtaining the measured temperature of the coiling pyrometer, and adjusting the feedback header; the step of judging whether the speed control header needs to be adjusted based on the speed change of the strip steel sample section comprises: calling a speed change judgment function to judge the speed change of the current strip steel sample section, which comprises: Comparing the speed V1 with a predicted speed V2 of the sample section of the strip after the high-temperature gauge at the exit of the finishing mill, if then the opening state of the speed control header is adjusted, wherein C is a configurable constant; calculating the speed V1 of the current strip steel sample section when reaching the speed control header; the step of determining the critical position of the speed control header comprises: calculating the delay distance of the speed control header based on the speed of the current strip steel sample section and the water valve delay response time of the speed control header; determining the critical position of the speed control header based on the delay distance and the position of the speed control header; the step of adjusting the speed control header comprises: predicting the temperature distribution of the strip steel between the speed control header and the coiling pyrometer to obtain the speed control predicted coiling temperature of the current strip steel sample section; adjusting the opening state of the speed control header based on the temperature difference between the speed control predicted coiling temperature and the target coiling temperature on the basis of the current opening state of the speed control header; the step of adjusting the feedback header comprises: obtaining the first feedback predicted coiling temperature of the current strip steel sample section and the second feedback predicted coiling temperature of the strip steel sample section reaching the coiling pyrometer at the moment; 2. The method of claim 1, wherein, adjusting the opening state of the feedback header based on the temperature difference between the measured temperature of the coiling pyrometer and the target coiling temperature and the temperature difference between the first feedback predicted coiling temperature and the second feedback predicted coiling temperature on the basis of the current opening state of the feedback header. The step of confirming the opening state of the cooling headers for cooling the strip steel comprises:

3. The method of claim 1, wherein, judging whether the two adjacent coils of the strip steel are the strip steels of the same layer based on the steel grade, thickness and target coiling temperature of the strip steel, if yes, the opening state of the cooling headers of the subsequent strip steel is used for the previous strip steel, otherwise, the opening state of the cooling headers of the subsequent strip steel is reconfirmed. The step of adjusting the feedforward header comprises: measuring the measured temperature of the current strip steel sample section by the finishing mill outlet pyrometer; 4. The method of claim 3, wherein, adjusting the opening state of the feedforward header based on the measured temperature measured by the finishing mill outlet pyrometer on the basis of the current opening state of the feedforward header. The method further comprises:

5. The method of claim 1, wherein, correcting the current TVD curve according to the measured speed of the strip steel sample section after the strip steel sample section passes through the finishing mill outlet pyrometer.

6. The method of claim 1, wherein, The finishing mill outlet pyrometer is an optical pyrometer or a radiation pyrometer. The coiling pyrometer is an optical pyrometer or a radiation pyrometer.

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