A control method for cold continuous rolling equipment
By gradually adjusting the roll gap and tension control in the cold rolling mill, the problem of unstable start-up of the cold rolling mill was solved, and stable reduction from hot-rolled thickness to finished product thickness was achieved, thus improving production stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHOUGANG ZHIXIN QIAN AN ELECTROMAGNETIC MATERIALS CO LTD
- Filing Date
- 2023-01-05
- Publication Date
- 2026-05-26
AI Technical Summary
Cold rolling mills have a high failure rate in starting up after unit maintenance or strip breakage, especially when rolling hard and brittle materials, which are affected by tension fluctuations and poor strip shape, leading to unstable starting up.
A control method is adopted to ensure that the strip tension is stable between rolling equipment by switching each rolling stand to the rolling force control mode and gradually adjusting the roll gap and tension. This includes roll gap control for the 1st, (n-1)th and nth stands until the strip reaches the coiling equipment, thus achieving stable rolling.
This enabled smooth and stable start-up of the cold rolling mill, improved production stability, and ensured the target of reducing thickness from hot-rolled thickness to finished product thickness.
Smart Images
Figure CN116078828B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of cold rolling technology, and more specifically, to a control method for cold rolling equipment. Background Technology
[0002] After maintenance or strip breakage of the cold rolling mill unit, the mill needs to be started to reduce the strip thickness from the hot-rolled thickness to the finished product thickness. When rolling hard and brittle materials, the failure rate of starting the mill when all stands of the cold rolling mill are started at the same time is extremely high due to the severe tension fluctuations and poor strip shape.
[0003] Therefore, those skilled in the art urgently need a control method for cold rolling mills that can ensure a smooth and stable start-up of the cold rolling mill. Summary of the Invention
[0004] The embodiments of this application provide a control method for a cold rolling mill, which can at least to a certain extent ensure a smooth start-up of the cold rolling mill.
[0005] 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.
[0006] According to one aspect of the embodiments of this application, a control method for a cold rolling mill is provided, the cold rolling mill comprising n sets of rolling stands, where n is an integer greater than or equal to 3, the method comprising: switching each rolling stand to a rolling force control mode, controlling each rolling stand to fully open its roll gap; for the first stand, adjusting the first roll gap of the first stand according to the corresponding first rolling force, controlling the cold rolling mill to start, and stopping the mill when the first deformation zone of the first stand reaches the exit of the cold rolling mill; for the second stand... For the (n-1) stand, adjust the (n-1) roll gap of the (n-1) stand according to the corresponding (n-1) rolling force, control the cold rolling mill to start, and stop when the first deformation zone of the first stand reaches the exit of the (n-1) stand; for the nth stand, adjust the nth roll gap of the nth stand according to the corresponding nth rolling force, control the cold rolling mill to start, and control the cold rolling mill to perform stable rolling when the first deformation zone of the first stand reaches the coiling device.
[0007] In some embodiments of this application, adjusting the first roll gap of the first stand according to the corresponding first rolling force includes: acquiring the corresponding first rolling force in real time; continuously closing the roll gap of the first stand until the first rolling force reaches the first rolling force set value.
[0008] In some embodiments of this application, after the first rolling force reaches the first rolling force set value, the method further includes: controlling the cold continuous rolling equipment to establish strip tension; if the strip tension is less than or equal to a predetermined tension value, opening the roll gap of the first stand, and then continuously closing the roll gap of the first stand until the first rolling force reaches the first rolling force set value.
[0009] In some embodiments of this application, after stopping the machine when the first deformation zone of the first stand reaches the exit of the cold rolling mill, the method further includes: obtaining the straightness of the second channel of the strip edge; if the straightness is within a preset range, then proceeding with the start-up process of the second stand; if the straightness is not within the preset range, then adjusting the bending roll force of the first stand and restarting the start-up process of the first stand.
[0010] In some embodiments of this application, the step of adjusting the bending roller force of the first frame and restarting the starting process of the first frame if the flatness is not within a preset range includes: if the flatness is greater than the upper limit of the preset range, increasing the bending roller force of the first frame by a preset value based on the original bending roller force, and restarting the starting process of the first frame; if the flatness is less than the lower limit of the preset range, decreasing the bending roller force of the first frame by the preset value based on the original bending roller force, and restarting the starting process of the first frame.
[0011] In some embodiments of this application, adjusting the (n-1) roll gap of the (n-1) stand according to the corresponding (n-1) rolling force includes: acquiring the corresponding first to (n-1) rolling forces in real time; continuously closing the roll gap of the first to (n-1) stands until the first to (n-1) rolling forces reach the set value of the first to (n-1) rolling forces.
[0012] In some embodiments of this application, after the first to (n-1) rolling forces reach the first to (n-1) rolling force set values, the method further includes: controlling the cold continuous rolling mill to establish strip tension; if the strip tension is less than or equal to a predetermined tension value, opening the roll gaps of the first to (n-1) stands, and then continuously closing the roll gaps of the first to (n-1) stands until the first to (n-1) rolling forces reach the first to (n-1) rolling force set values.
[0013] In some embodiments of this application, adjusting the nth roll gap of the nth stand according to the corresponding nth rolling force includes: acquiring the corresponding first to nth rolling forces in real time; continuously closing the roll gaps of the first to nth stands until the first to nth rolling forces reach the set values of the first to nth rolling forces.
[0014] In some embodiments of this application, after the first to n rolling forces reach the first to n rolling force set values, the method further includes: controlling the cold continuous rolling equipment to establish strip tension; if the strip tension is less than or equal to a predetermined tension value, opening the roll gaps of the first to n stands, and then continuously closing the roll gaps of the first to n stands until the first to n rolling forces reach the first to n rolling force set values.
[0015] In some embodiments of this application, when the first deformation zone of the first stand reaches the coiling device, the cold continuous rolling equipment is controlled to perform stable rolling: the speed is increased to above the shearing speed to achieve cold continuous rolling.
[0016] Based on the above solution, the technical solution provided in this application has at least the following advantages and advancements:
[0017] In this application, by performing corresponding start-stop control at the start-up state, the first stand thinning, the i-th stand thinning (i = 2 to n-1), and the n-th stand thinning (n is the last stand), the strip tension is stably formed between the rolling equipment, thereby achieving the goal of reducing the thickness from hot-rolled thickness to finished product thickness, realizing smooth start-up rolling of the cold continuous rolling mill, and improving production stability.
[0018] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this application. Attached Figure Description
[0019] 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. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:
[0020] Figure 1 A simplified flowchart of a control method for a cold rolling mill according to an embodiment of this application is shown;
[0021] Figure 2 A simplified flowchart of a control method for a cold rolling mill according to an embodiment of this application is shown;
[0022] Figure 3 A simplified flowchart of a control method for a cold rolling mill according to an embodiment of this application is shown;
[0023] Figure 4 A simplified flowchart of a control method for a cold rolling mill according to an embodiment of this application is shown;
[0024] Figure 5A simplified flowchart of a control method for a cold rolling mill according to an embodiment of this application is shown. Detailed Implementation
[0025] 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.
[0026] Please see Figure 1 .
[0027] Figure 1 A simplified flowchart of a control method for a cold rolling mill according to an embodiment of this application is shown. The cold rolling mill includes n sets of rolling stands, where n is an integer greater than or equal to 3. The method may include steps S101-S104:
[0028] Step S101: Switch each rolling mill stand to rolling force control mode and control each rolling mill stand to fully open the roll gap.
[0029] Step S102: For the first stand, adjust the first roll gap of the first stand according to the corresponding first rolling force, control the cold rolling mill to start, and stop when the first deformation zone of the first stand reaches the exit of the cold rolling mill.
[0030] Step S103: For the (n-1)th stand, adjust the (n-1)th roll gap of the (n-1)th stand according to the corresponding (n-1)th rolling force, control the cold continuous rolling equipment to start, and stop when the first deformation zone of the first stand reaches the exit of the (n-1)th stand;
[0031] Step S104: For the nth stand, adjust the nth roll gap of the nth stand according to the corresponding nth rolling force, control the cold continuous rolling equipment to start, and control the cold continuous rolling equipment to perform stable rolling when the first deformation zone of the first stand reaches the coiling equipment.
[0032] In this application, by performing corresponding start-stop control at the start-up state, the first stand thinning, the i-th stand thinning (i = 2 to n-1), and the n-th stand thinning (n is the last stand), the strip tension is stably formed between the rolling equipment, thereby achieving the goal of reducing the thickness from hot-rolled thickness to finished product thickness, realizing smooth start-up rolling of the cold continuous rolling mill, and improving production stability.
[0033] Please see Figure 2 .
[0034] Figure 2A simplified flowchart of a control method for a cold rolling mill according to an embodiment of this application is shown. The method for adjusting the first roll gap of the first stand according to the corresponding first rolling force may include steps S201-S202:
[0035] Step S201: Obtain the corresponding first rolling force in real time;
[0036] Step S202: Continuously close the roll gap of the first stand until the first rolling force reaches the first rolling force set value.
[0037] In this application, after the first rolling force reaches the first rolling force set value, the method may further include: controlling the cold continuous rolling equipment to establish strip tension; if the strip tension is less than or equal to a predetermined tension value, opening the roll gap of the first stand, and then continuously closing the roll gap of the first stand until the first rolling force reaches the first rolling force set value.
[0038] Please see Figure 3 .
[0039] Figure 3 A simplified flowchart of a control method for a cold rolling mill according to an embodiment of this application is shown. After stopping the mill when the first deformation zone of the first stand reaches the exit of the cold rolling mill, the method may further include steps S301-S302:
[0040] Step S301: Obtain the straightness of the second channel of the strip edge. If the straightness is within the preset range, proceed with the starting process of the second frame.
[0041] Step S302: If the flatness is not within the preset range, adjust the bending roller force of the first frame and restart the starting process of the first frame.
[0042] In this application, if the flatness is not within a preset range, the method of adjusting the bending roller force of the first frame and restarting the starting process of the first frame may include: if the flatness is greater than the upper limit of the preset range, increasing the bending roller force of the first frame by a preset value based on the original bending roller force, and restarting the starting process of the first frame; if the flatness is less than the lower limit of the preset range, decreasing the bending roller force of the first frame by the preset value based on the original bending roller force, and restarting the starting process of the first frame.
[0043] Therefore, in this application, the thinning operation for the first rack can be performed in the following order:
[0044] (1) Close the roll gap of the first stand until the first rolling force reaches a times the set value, where a = 0.8 to 1.3;
[0045] (2) Establish tension at the inlet and outlet of the cold rolling mill. The actual tension is >e tons and e > 0.5. If the actual tension is ≤e, open the roll gap of the first stand and then close the roll gap of the first stand to the required rolling force value.
[0046] (3) Start the emulsion injection of the first stand and the air purging of the rolling mill section;
[0047] (4) Press the start button and stop the machine when the deformation zone of the first stand passes the plate shaper at the exit of the cold rolling mill.
[0048] (5) If the strip shaper shows that the straightness of the second channel of the strip edge is within ±10I-Unit, proceed to the second stand start-up process; if the strip shaper shows that the straightness of the second channel of the strip edge is >10I-Unit, increase the bending roller force f tons of the first stand and start the first stand again; if the strip shaper shows that the straightness of the second channel of the strip edge is <-10I-Unit, decrease the bending roller force f tons of the first stand and start the first stand again.
[0049] Please see Figure 4 .
[0050] Figure 4 A simplified flowchart of a control method for a cold rolling mill according to an embodiment of this application is shown. The method for adjusting the (n-1)th roll gap of the (n-1)th stand according to the corresponding (n-1)th rolling force may include steps S401-S402:
[0051] Step S401: Obtain the corresponding rolling forces from the 1st to (n-1)th in real time;
[0052] Step S402: Continuously close the roll gaps of the first to (n-1) stands until the rolling forces of the first to (n-1) stands reach the set values of the rolling forces of the first to (n-1) stands.
[0053] In this application, after the rolling forces of the first to (n-1)th rolling forces reach the set values of the first to (n-1)th rolling forces, the method may further include: controlling the cold continuous rolling mill to establish strip tension; if the strip tension is less than or equal to a predetermined tension value, opening the roll gaps of the first to (n-1)th stands, and then continuously closing the roll gaps of the first to (n-1)th stands until the rolling forces of the first to (n-1)th rolling forces reach the set values of the first to (n-1)th rolling forces.
[0054] Therefore, in this application, the thinning operation for the (n-1)th rack can be performed in the following order:
[0055] (1) Close the roll gap of the first stand until the rolling force reaches a times the set value, and close the roll gap of the second to i stands until the rolling force reaches b times the set value, where b = 0.8 to 1.3;
[0056] (2) Establish tension at the inlet and outlet of the cold rolling mill. The actual tension is >e tons and e > 0.5. If the actual tension is ≤e, open the roll gap of the first to (n-1) stands and then close the roll gap of the first to (n-1) stands to the required rolling force value.
[0057] (3) Start the emulsion injection of the first to (n-1) stands and the air purging of the rolling mill section;
[0058] (4) Press the start button and stop the machine when the deformation zone of the first frame reaches the exit of the first to (n-1) frames.
[0059] Please see Figure 5 .
[0060] Figure 5 A simplified flowchart of a control method for a cold rolling mill according to an embodiment of this application is shown. The method for adjusting the nth roll gap of the nth stand according to the corresponding nth rolling force may include steps S501-S502:
[0061] Step S501: Obtain the corresponding rolling forces from the 1st to the nth in real time;
[0062] Step S502: Continuously close the roll gaps of stands 1 to n until the rolling forces of stands 1 to n reach the set values of rolling forces of stands 1 to n.
[0063] In this application, after the rolling forces of the first to nth stands reach the set values of the first to nth rolling forces, the method may further include: controlling the cold continuous rolling mill to establish strip tension; if the strip tension is less than or equal to a predetermined tension value, opening the roll gaps of the first to nth stands, and then continuously closing the roll gaps of the first to nth stands until the rolling forces of the first to nth stands reach the set values of the first to nth rolling forces.
[0064] Therefore, in this application, the thinning operation for the nth rack can be performed in the following order:
[0065] (1) Close the roll gap of the first stand until the rolling force reaches a times the set value, close the roll gap of the second to (n-1) stands until the rolling force reaches b times the set value, b = 0.8 to 1.3, close the roll gap of the nth stand until the rolling force reaches c times the set value, c = 0.8 to 1.3;
[0066] (2) Establish tension at the mill inlet and outlet. The actual tension is >e tons, e > 0.5. If the actual tension is ≤e, open the roll gap of the first to nth stands and then close the roll gap of the first to nth stands to the required rolling force value.
[0067] (3) Start the emulsion spraying of all stands and the air purging of the rolling mill section;
[0068] (4) Press the start button. Wait until the deformation zone of the first stand reaches the coiler, then increase the speed to above the shearing speed for rolling to achieve cold tandem rolling.
[0069] To enable those skilled in the art to understand the present application more deeply, the following will be described in conjunction with actual embodiments.
[0070] The existing cold tandem mill equipment is a 4-stand cold tandem mill, where n = 4.
[0071] 1. Starting state
[0072] The first to fourth stands are in the rolling force control mode, and the roll gaps are opened.
[0073] 2. Thinning of the first stand
[0074] (1) Close the roll gap of the first stand until the rolling force reaches a times the set value, where a = 1.1;
[0075] (2) Establish tensions at the inlet and outlet of the mill. The actual tension = 1.5 tons, e = 0.7, and the actual tension > e;
[0076] (3) Start the emulsion spraying of the first stand and the air purge of the mill section;
[0077] (4) Press the start button. Wait until the deformation zone of the first stand passes the shape meter at the outlet of the cold tandem mill, then stop.
[0078] (5) The shape meter shows that the flatness of the second channel at the strip edge is 15 I-Unit. Increase the bending roll force of the first stand by 2 tons and start the first stand again.
[0079] (6) Close the roll gap of the first stand until the rolling force reaches a times the set value, where a = 1.1;
[0080] (7) Establish tensions at the inlet and outlet of the mill. The actual tension = 0.5 tons, e = 0.7, and the actual tension < e. Open the roll gap of the first stand, and then close the roll gap of the first stand to the required rolling force value;
[0081] (8) Start the emulsion spraying of the first stand and the air purge of the mill section;
[0082] (9) Press the start button. Wait until the deformation zone of the first stand passes the shape meter at the outlet of the cold tandem mill, then stop.
[0083] (10) The shape meter shows that the flatness of the second channel at the strip edge is 5 I-Unit. Enter the start-up process of the second stand.
[0084] 3. Thinning of the second stand
[0085] (1) Close the roll gap of the first stand until the rolling force reaches 1.1 times the set value, and close the roll gap of the second stand until the rolling force reaches b times the set value, where b = 1.2;
[0086] (2) Tension is established at the mill inlet and outlet, and the actual tension = 0.9 tons > e;
[0087] (3) Start the emulsion injection of the first and second stands and the air purging of the rolling mill section;
[0088] (4) Press the start button and stop the machine when the deformation zone of the first frame reaches the exit of the third frame.
[0089] 4. Thinning of the third frame
[0090] (1) Close the roll gap of the first stand until the rolling force reaches 1.1 times the set value, and close the roll gap of the second and third stands until the rolling force reaches b times the set value, where b = 1.2;
[0091] (2) Tension is established at the mill inlet and outlet, and the actual tension = 1.2 tons > e;
[0092] (3) Start the emulsion injection of the first to third stands and the air purging of the rolling mill section;
[0093] (4) Press the start button and stop the machine when the deformation zone of the first frame reaches the exit of the fourth frame.
[0094] 5. Thinning of the 4th frame (4 is the last frame)
[0095] (1) Close the roll gap of the first stand until the rolling force reaches 1.1 times the set value, close the roll gap of the second and third stands until the rolling force reaches b times the set value, b = 1.2, close the roll gap of the fourth stand until the rolling force reaches c times the set value, c = 0.9;
[0096] (2) Tension is established at the mill inlet and outlet, and the actual tension = 1.3 tons > e;
[0097] (3) Start the emulsion spraying of all stands and the air purging of the rolling mill section;
[0098] (4) Press the start button. When the deformation zone of the first frame reaches the coiler, increase the speed to a shearing speed of 150mpm or more to achieve cold continuous rolling.
[0099] In summary, in this application, corresponding start-stop control can be performed at the start-up state, the first stand thinning, the i-th stand thinning (i = 2 to n-1), and the n-th stand thinning (n is the last stand), so that the strip tension is stably formed between the rolling equipment, thereby achieving the goal of reducing the thickness from hot rolled thickness to finished product thickness, realizing smooth start-up rolling of the cold continuous rolling mill, and improving production stability.
[0100] 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.
[0101] 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 a cold continuous rolling mill, characterized in that, The cold continuous rolling mill includes n sets of rolling stands, where n is an integer greater than or equal to 3, and the method includes: Switch each rolling mill stand to rolling force control mode to control the roll gap of each rolling mill stand to be fully open; For the first stand, the first roll gap of the first stand is adjusted according to the corresponding first rolling force, and the cold rolling mill is controlled to start up. When the first deformation zone of the first stand reaches the exit of the cold rolling mill, the mill stops. For the (n-1)th stand, the (n-1)th roll gap of the (n-1)th stand is adjusted according to the corresponding (n-1)th rolling force, and the cold continuous rolling equipment is controlled to start up. When the first deformation zone of the first stand reaches the exit of the (n-1)th stand, the machine is stopped. For the nth stand, the nth roll gap of the nth stand is adjusted according to the corresponding nth rolling force to control the cold rolling mill to start. When the first deformation zone of the first stand reaches the coiling device, the cold rolling mill is controlled to perform stable rolling. After stopping the cold rolling mill when the first deformation zone of the first stand reaches the exit of the cold rolling mill, the method further includes: Obtain the straightness of the second channel at the edge of the strip. If the straightness is within a preset range, proceed with the starting process of the second frame. If the flatness is not within the preset range, the bending roller force of the first frame is adjusted, and the starting process of the first frame is repeated.
2. The method according to claim 1, characterized in that, The step of adjusting the first roll gap of the first stand according to the corresponding first rolling force includes: Real-time acquisition of the corresponding first rolling force; The first stand roll gap is continuously closed until the first rolling force reaches the first rolling force set value.
3. The method according to claim 2, characterized in that, After the first rolling force reaches the first rolling force set value, the method further includes: The cold rolling mill is controlled to establish strip tension. If the strip tension is less than or equal to a predetermined tension value, the roll gap of the first stand is opened, and then the roll gap of the first stand is continuously closed until the first rolling force reaches the first rolling force set value.
4. The method according to claim 1, characterized in that, If the flatness is not within the preset range, the bending roller force of the first frame is adjusted, and the starting process of the first frame is repeated, including: If the flatness is greater than the upper limit of the preset range, then the bending roller force of the first frame is increased by a preset value based on the original bending roller force, and the starting process of the first frame is repeated. If the flatness is less than the lower limit of the preset range, the preset value of the bending roller force is reduced based on the original bending roller force of the first frame, and the starting process of the first frame is repeated.
5. The method according to claim 1, characterized in that, The step of adjusting the (n-1)th roll gap of the (n-1)th stand according to the corresponding (n-1)th rolling force includes: Real-time acquisition of the corresponding rolling forces from the 1st to (n-1)th; The roll gaps of stands 1 to (n-1) are continuously closed until the rolling forces of stands 1 to (n-1) reach the set values of rolling forces 1 to (n-1).
6. The method according to claim 5, characterized in that, After the first to (n-1) rolling forces reach the set values of the first to (n-1) rolling forces, the method further includes: The cold rolling mill is controlled to establish strip tension. If the strip tension is less than or equal to the predetermined tension value, the roll gaps of the first to (n-1) stands are opened, and then the roll gaps of the first to (n-1) stands are continuously closed until the rolling force of the first to (n-1) stands reaches the set value of the rolling force of the first to (n-1) stands.
7. The method according to claim 1, characterized in that, The step of adjusting the nth roll gap of the nth stand according to the corresponding nth rolling force includes: Real-time acquisition of the corresponding rolling forces from the 1st to the nth; The roll gaps of stands 1 to n are continuously closed until the rolling forces of stands 1 to n reach the set values of rolling forces 1 to n.
8. The method according to claim 7, characterized in that, After the rolling forces from the first to the nth point reach their respective set values, the method further includes: The cold rolling mill is controlled to establish strip tension. If the strip tension is less than or equal to a predetermined tension value, the roll gaps of the first to n stands are opened, and then the roll gaps of the first to n stands are continuously closed until the rolling forces of the first to n stands reach the set values of the first to n rolling forces.
9. The method according to claim 1, characterized in that, When the first deformation zone of the first stand reaches the coiling device, the cold continuous rolling mill is controlled to perform stable rolling: The rolling speed is increased to above the shearing speed to achieve cold continuous rolling.