A method of controlling a rolling mill
By obtaining the strip specifications and shape cloud map in the 18-roll mill, the reduction rate and tension of the last pass were controlled, which solved the problem of identifying and eliminating inclined wave shape defects and improved production quality.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHOUGANG GROUP CO LTD
- Filing Date
- 2023-08-30
- Publication Date
- 2026-07-14
Smart Images
Figure CN117181821B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of cold rolling technology, and more specifically, to a control method for rolling equipment. Background Technology
[0002] The 18-roll mill, with its small work roll diameter and strong reduction capacity, has particularly significant advantages in rolling high-strength steel and precision-drawn steel. However, the 18-roll mill employs a design without bearings or bearing seats on the work rolls. In actual production, due to the complex structure of the mill's roll system, various factors lead to excessive axial forces in the roll system, frequently resulting in tilting and wavy plate shape defects. This severely affects on-site production and product quality, failing to meet user requirements. Therefore, eliminating tilting and wavy plate shape defects is a crucial challenge. Currently, there are no accurate methods for characterizing and judging tilting and wavy plate shape defects, and even more so, there is a lack of effective technical methods and means to eliminate them. Summary of the Invention
[0003] The embodiments of this application provide a control method for rolling equipment, which can at least to some extent characterize and determine inclined corrugated plate defects, and effectively eliminate inclined corrugated plate defects.
[0004] Other features and advantages of this application will become apparent from the following detailed description, or may be learned in part from practice of this application.
[0005] According to one aspect of the embodiments of this application, a control method for a rolling mill is provided, wherein the rolling mill is an 18-roll mill, the method comprising: obtaining the incoming strip specifications to determine the rolling pass scheme of the rolling mill; after rolling any pass according to the rolling pass scheme, obtaining the strip shape contour map; and controlling the reduction rate and strip tension of the last pass of the rolling mill according to the strip shape contour map corresponding to each rolling pass.
[0006] In some embodiments of this application, obtaining the incoming strip specifications to determine the rolling pass scheme of the rolling mill includes: obtaining the incoming strip specifications, determining the total reduction rate based on the incoming strip specifications, and determining the number of rolling passes based on the total reduction rate to determine the rolling pass scheme of the rolling mill.
[0007] In some embodiments of this application, based on the foregoing scheme, determining the number of rolling passes according to the total reduction rate includes: if the total reduction rate is less than 50%, determining the number of rolling passes to be 3; if the total reduction rate is greater than or equal to 50%, determining the number of rolling passes to be 5.
[0008] In some embodiments of this application, controlling the reduction rate and strip tension of the last pass of the rolling mill based on the strip shape cloud diagram corresponding to each rolling pass includes: determining whether the strip has a strip shape defect after each rolling pass is completed based on the strip shape cloud diagram corresponding to each rolling pass, and then controlling the reduction rate and strip tension of the last pass of the rolling mill based on the determination result.
[0009] In some embodiments of this application, based on the aforementioned scheme, determining whether the strip has a shape defect after completing each rolling pass according to the strip shape cloud map corresponding to each rolling pass includes: if the strip shape cloud map corresponding to the target rolling pass is in a wave pattern and has periodically distributed oblique stripes, and the strip shape meter shows a longitudinal extension distribution of alternating positive and negative tension along the width direction of the strip, it is determined that the strip has a shape defect after completing the target rolling pass; wherein, the target rolling pass is any one of the rolling passes.
[0010] In some embodiments of this application, based on the foregoing scheme, controlling the reduction rate and strip tension of the last pass of the rolling mill according to the judgment result includes: if the strip exhibits a shape defect after completing any rolling pass, adjusting the reduction rate and strip tension of the last pass of the rolling mill; if the shape defect disappears after completing any rolling pass of the strip, canceling the adjustment of the reduction rate and strip tension of the last pass of the rolling mill.
[0011] In some embodiments of this application, based on the foregoing scheme, the method further includes: if the strip steel exhibits a shape defect after completing any rolling pass, characterizing the shape defect based on the characteristics of the shape defect.
[0012] In some embodiments of this application, based on the aforementioned scheme, the step of controlling the reduction rate of the last pass of the rolling mill if the strip steel exhibits a shape defect after completing any rolling pass includes: if the strip steel exhibits a shape defect after completing any rolling pass, adjusting the reduction rate of the last pass of the rolling mill to within 3% and using a flattening rolling mode.
[0013] In some embodiments of this application, based on the foregoing scheme, the step of controlling the strip tension of the last pass of the rolling mill if the strip has a shape defect after completing any rolling pass includes: if the strip has a shape defect after completing any rolling pass, adjusting the strip tension of the last pass of the rolling mill to increase by 20%-30% on the original basis.
[0014] Based on the above solution, this application has at least the following advantages or advancements:
[0015] In some embodiments of this application, the technical solutions provided include obtaining the strip shape cloud map after any rolling pass, and then controlling the reduction rate and strip tension of the last pass of the rolling equipment according to the strip shape cloud map corresponding to each rolling pass. This allows for the identification and judgment of strip shape defects. By adjusting the reduction rate and strip tension of the last pass, strip shape defects can be effectively eliminated.
[0016] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description
[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.
[0018] Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0019] In the attached diagram:
[0020] Figure 1 A simplified schematic diagram of a rolling apparatus according to one embodiment of this application is shown;
[0021] Figure 2 A schematic diagram of an inclined wave-shaped defect according to an embodiment of this application is shown;
[0022] Figure 3 A flowchart of a control method for a rolling mill according to an embodiment of this application is shown;
[0023] Figure 4 A flowchart of a control method for a rolling mill according to an embodiment of this application is shown;
[0024] Figure 5 A contour plot of a tilted wave-shaped defect is shown in one embodiment of this application;
[0025] Figure 6 A simplified diagram showing the display results of a plate shape meter for inclined wave plate defects according to one embodiment of this application is shown;
[0026] Figure 7 A flowchart of a control method for a rolling mill according to an embodiment of this application is shown;
[0027] Figure 8 A schematic diagram of the measurement of inclined wave-shaped defects according to one embodiment of this application is shown. Detailed Implementation
[0028] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.
[0029] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.
[0030] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.
[0031] The implementation details of the technical solutions in the embodiments of this application are described in detail below:
[0032] Please see Figure 1 .
[0033] Figure 1 A simplified schematic diagram of a rolling apparatus according to an embodiment of this application is shown, as follows: Figure 1 As shown, the 18-roll mill, with its small work roll diameter and strong pressing capacity, has a particularly significant advantage in rolling high-strength steel and precision-stamped steel. However, the 18-roll mill adopts a design with no bearings and no bearing seats for the work rolls. In actual production, due to the relatively complex structure of the mill's roll system, many factors lead to excessive axial force in the roll system, resulting in frequent tilting and complex plate shape defects.
[0034] Please see Figure 2 .
[0035] Figure 2 A schematic diagram of an inclined wave-shaped defect according to an embodiment of this application is shown, as follows: Figure 2 As shown, the appearance of inclined corrugated plates will seriously affect on-site production and product quality, and will fail to meet user requirements.
[0036] Please see Figure 3 .
[0037] Figure 3A flowchart illustrating a control method for a rolling mill according to an embodiment of this application is shown, wherein the rolling mill is an 18-roll mill, as... Figure 3 As shown, the method may include steps S301-S303:
[0038] Step S301: Obtain the incoming strip specifications to determine the rolling pass scheme of the rolling equipment.
[0039] Step S302: After rolling any pass according to the rolling pass scheme, obtain the strip shape cloud map.
[0040] Step S303: Based on the strip shape cloud diagram corresponding to each rolling pass, control the reduction rate and strip tension of the last pass of the rolling equipment.
[0041] In this application, by obtaining the strip shape cloud map after any rolling pass, and then controlling the reduction rate and strip tension of the last pass of the rolling equipment according to the strip shape cloud map corresponding to each rolling pass, strip shape defects can be identified and judged. By adjusting the reduction rate and strip tension of the last pass, strip shape defects can be effectively eliminated.
[0042] Please see Figure 4 .
[0043] Figure 4 A flowchart of a control method for a rolling mill according to an embodiment of this application is shown. In step S301, the method of obtaining the incoming strip specifications to determine the rolling pass scheme of the rolling mill may include steps S401-S402:
[0044] Step S401: Obtain the incoming strip specifications and determine the total reduction rate based on the incoming strip specifications.
[0045] Step S402: Determine the number of rolling passes based on the total reduction rate, so as to determine the rolling pass scheme of the rolling equipment.
[0046] In this application, the number of rolling passes and the required reduction rate for each rolling pass can be determined based on the incoming strip specifications and finished product specifications. Specifically, if the total reduction rate is less than 50%, the number of rolling passes is determined to be 3; if the total reduction rate is greater than or equal to 50%, the number of rolling passes is determined to be 5. The reduction rate for each rolling pass can be evenly distributed or set according to requirements; this application does not impose specific limitations.
[0047] In this application, the method for controlling the reduction rate and strip tension of the last pass of the rolling mill based on the strip shape cloud diagram corresponding to each rolling pass may include: determining whether the strip has a strip shape defect after each rolling pass is completed based on the strip shape cloud diagram corresponding to each rolling pass, and then controlling the reduction rate and strip tension of the last pass of the rolling mill based on the determination result.
[0048] In this application, if the strip shape cloud map corresponding to the target rolling pass is in a wave pattern and has oblique stripes with periodic distribution, and the strip shape meter shows a longitudinal extension distribution of alternating positive and negative tension along the width direction of the strip, it is determined that the strip has a strip shape defect after the target rolling pass is completed; wherein, the target rolling pass is any one of the rolling passes.
[0049] For example, please see Figure 5 and Figure 6 , Figure 5 A contour plot of a tilted wave-shaped defect according to one embodiment of this application is shown. Figure 6 A simplified diagram showing the display results of a plate shape meter for inclined wave-shaped defects according to one embodiment of this application is illustrated. Figure 5 and Figure 6 As shown, in this embodiment, the strip shape cloud map shows a medium wave pattern and has oblique stripes with periodic distribution. When the strip shape meter shows a longitudinal extension distribution of alternating positive and negative fluctuations along the width direction, it is determined that there is an oblique wave shape defect.
[0050] In this application, the method for controlling the reduction rate and strip tension of the last pass of the rolling mill based on the judgment result may include: if the strip exhibits a shape defect after completing any rolling pass, adjusting the reduction rate and strip tension of the last pass of the rolling mill; if the shape defect disappears after completing any rolling pass of the strip, canceling the adjustment of the reduction rate and strip tension of the last pass of the rolling mill.
[0051] In this application, if the strip steel exhibits shape defects after completing any rolling pass, the reduction rate of the last pass of the rolling equipment can be adjusted to within 3%, and a leveling rolling mode can be adopted.
[0052] In this application, if the strip steel develops a shape defect after completing any rolling pass, the strip steel tension in the last pass of the rolling equipment can be increased by 20%-30% based on the original tension.
[0053] To enable those skilled in the art to gain a deeper understanding of this application, please refer to the following: Figure 7 , Figure 7 A flowchart illustrating a control method for a rolling mill according to an embodiment of this application is shown, as follows: Figure 7As shown, the detailed process may include:
[0054] S1 determines the rolling pass based on the specifications of the incoming strip steel.
[0055] S2 determines the reduction rate for each pass;
[0056] S3 determines the tension for each pass;
[0057] S4 performs the first rolling pass;
[0058] S5 online system uses plate shape cloud diagrams to determine whether there are tilted wave plate shape defects;
[0059] If there is no inclined corrugated plate defect in S6, proceed to the next pass normally; if there is an inclined corrugated plate defect, the last pass adopts the "high tension + low reduction rate" mode, adjust the reduction rate and tension of the remaining passes, and proceed to the next pass.
[0060] S7 repeats steps 5 to 6 above until the rolling process ends.
[0061] In this application, if the strip steel exhibits shape defects after completing any rolling pass, the shape defects can be characterized based on their characteristics.
[0062] For example, Figure 8 A schematic diagram of the measurement of inclined corrugated plate defects according to one embodiment of this application is shown. Figure 8 As shown, to facilitate the measurement of inclined wave plate defects, the inclined wave plate defects are characterized according to their characteristics. The specific parameters are as follows: the spacing of the inclined waves in the inclined direction is a; the spacing of the inclined waves in the rolling direction is b; the width of the inclined wave occurrence area is c; the height of the inclined waves is d; and the inclination angle of the inclined waves is θ.
[0063] To enable those skilled in the art to gain a deeper understanding of this application, the following detailed description will be provided through specific embodiments.
[0064] Example 1:
[0065] SLMF1 fine-drawing steel was produced using an 18-roll mill, with a specification of 2.3mm*1000mm rolled into 1.1*1000mm strip. A 5-pass rolling process was employed, with the final pass using a "low tension + high reduction rate" mode. The final pass reduction rate was 6.0%, the final pass inlet tension was 96.3MPa, and the final pass outlet tension was 148.8MPa. The exit strip exhibited a tilted, corrugated shape defect.
[0066] Using the characterization method for inclined wave-shaped defects provided in this application, the inclined wave-shaped defects of the sampled steel plate were measured, including the spacing of the inclined waves in the inclined direction as a; the spacing of the inclined waves in the rolling direction as b; the width of the inclined wave occurrence area as c; the height of the inclined waves as d; and the inclination angle of the inclined waves as θ. The results are shown in Table 1.
[0067]
[0068] Table 1 Measurement Results
[0069] Example 2:
[0070] SLMF1 fine-blanking steel, 2.3mm*1000mm, is produced using an 18-roll mill.
[0071] 1.1*1000mm. It adopts a 5-pass rolling process, with the last pass using a "high tension + low reduction rate" mode. The reduction rate of the last pass is 2.8%, the inlet tension of the last pass is 118.0MPa, the outlet tension of the last pass is 194.7MPa, and the strip shape at the outlet is good.
[0072] In summary, the technical solution provided in this application can identify and determine strip shape defects by obtaining the strip shape cloud map after any rolling pass, and then controlling the reduction rate and strip tension of the last pass of the rolling equipment according to the strip shape cloud map corresponding to each rolling pass. By adjusting the reduction rate and strip tension of the last pass, strip shape defects can be effectively eliminated.
[0073] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the embodiments disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.
[0074] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.
Claims
1. A control method for rolling mill equipment, characterized in that, The rolling equipment is an 18-roll mill, and the method includes: Obtain the incoming strip specifications to determine the rolling pass scheme of the rolling equipment; According to the rolling pass scheme, after any rolling pass, the strip shape cloud map is obtained; If the strip shape cloud diagram corresponding to the target rolling pass is in a wave pattern and has periodically distributed oblique stripes, and the strip shape meter shows a longitudinal extension distribution of alternating positive and negative tension along the width direction of the strip, it is determined that the strip has a strip shape defect after the target rolling pass is completed; wherein, the target rolling pass is any one of the rolling passes; The reduction rate and strip tension of the last pass of the rolling mill are controlled based on the judgment result. The step of controlling the reduction rate and strip tension of the final pass of the rolling mill based on the judgment result includes: If the strip exhibits shape defects after any rolling pass, the reduction rate of the last pass of the rolling mill is adjusted, and the strip tension of the last pass of the rolling mill is increased by 20%-30% from the original value. If the strip exhibits shape defects after completing any rolling pass, adjusting the reduction rate of the final pass of the rolling mill includes: If the strip exhibits shape defects after any rolling pass, the reduction rate of the last pass of the rolling equipment shall be adjusted to within 3%.
2. The method according to claim 1, characterized in that, The process of obtaining the incoming strip specifications to determine the rolling pass scheme of the rolling equipment includes: Obtain the incoming strip specifications and determine the total reduction rate based on the incoming strip specifications; Based on the total reduction rate, the number of rolling passes is determined to determine the rolling pass scheme of the rolling equipment.
3. The method according to claim 2, characterized in that, The step of determining the number of rolling passes based on the total reduction rate includes: If the total reduction rate is less than 50%, the number of rolling passes is determined to be 3. If the total reduction rate is greater than or equal to 50%, the number of rolling passes is determined to be 5.
4. The method according to claim 1, characterized in that, The method of controlling the reduction rate and strip tension of the final pass of the rolling mill based on the judgment result also includes: If the strip shape defects disappear after any rolling pass, then the adjustment of the reduction rate and strip tension of the last pass of the rolling equipment is cancelled.
5. The method according to claim 1, characterized in that, The method further includes: If the strip exhibits shape defects after completing any rolling pass, the shape defects are characterized based on their features.
6. The method according to claim 1, characterized in that, The method of adjusting the reduction rate of the last pass of the rolling mill if a strip steel develops a shape defect after completing any rolling pass further includes: If the strip exhibits shape defects after completing any rolling pass, a leveling rolling mode shall be adopted.