A production control method for hot-rolled variable thickness strip steel

Abstract

The embodiment of the present application provides a production control method for hot-rolled variable thickness strip steel, the method comprising: setting a thickness variation parameter of the strip steel according to the product requirements of the hot continuous rolling strip steel, the thickness variation parameter being used to characterize the thickness variation during the strip steel production process; obtaining strip steel production parameters, the strip steel production parameters including intermediate billet parameters, head cutting amount, tail cutting amount, finished strip steel thickness, and real-time rolling speed; determining the thickness variation rate of the strip steel in the thickening section over time based on the thickness variation parameter and the strip steel production parameter; after triggering a thickening continuous rolling signal for the strip steel, performing variable thickness hot continuous rolling according to the thickness variation rate over time. The technical solution of the embodiment of the present application can produce variable thickness strip steel without adding any hardware products and investment.

Description

Technical Field

[0001] The present application relates to the technical field of hot rolling, and in particular to a production control method for hot-rolled variable thickness strip steel. Background Art

[0002] As the market demand for variable-wall thickness continuous oil pipes continues to grow, the original production lines are unable to meet the production of variable-thickness strip steel, and the cost required to redesign or transform the production lines is too high, which seriously restricts the development of the variable-wall thickness continuous oil pipe industry.

[0003] Based on this, technical personnel in this field urgently need a production control method for hot-rolled variable thickness strip steel, which can produce variable thickness strip steel without adding any hardware products and investments. Summary of the invention

[0004] The embodiments of the present application provide a production control method for hot-rolled variable thickness strip steel, thereby enabling the production of variable thickness strip steel to at least a certain extent without adding any hardware products and investments.

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

[0006] According to one aspect of an embodiment of the present application, a production control method for hot-rolled variable-thickness strip is provided, the method comprising: setting a thickness variation parameter of the strip according to product requirements of the hot-rolled strip, the thickness variation parameter being used to characterize the thickness variation during the strip production process; acquiring strip production parameters, the strip production parameters comprising intermediate billet parameters, head cutting amount, tail cutting amount, finished strip thickness and real-time rolling speed; determining a thickness variation rate of the strip in a thickening section over time based on the thickness variation parameter and the strip production parameters; and performing variable-thickness hot rolling according to the thickness variation rate over time after triggering a thickening and continuous rolling signal for the strip.

[0007] In some embodiments of the present application, the thickness variation parameters include: thickness variation of the head and tail, length of the head of the thickness straight section, and length of the tail of the thickness straight section.

[0008] In some embodiments of the present application, determining the thickness change rate of the strip in the thickening section over time based on the thickness change parameter and the strip production parameter includes: determining the predicted finished length of the strip based on the thickness change parameter and the strip production parameter; calculating the thickness change rate of the strip in the thickening section over time based on the thickness change parameter and the predicted finished length.

[0009] In some embodiments of the present application, based on the above solution, determining the predicted finished length of the steel strip based on the thickness variation parameter and the steel strip production parameter includes:

[0010] The predicted finished length of the strip is calculated according to the following formula:

[0011]

[0012] Among them, L2 is the predicted finished length of the strip, l1 is the head length of the thickness straight section, l2 is the tail length of the thickness straight section, L1 is the intermediate billet length of the strip, h2 is the finished strip thickness, h1 is the intermediate billet thickness, x is the head cutting amount, y is the tail cutting amount, and Δh is the thickness change of the head and tail.

[0013] In some embodiments of the present application, based on the aforementioned scheme, the thickness change rate of the strip in the thickening section over time is calculated based on the thickness change parameter and the predicted finished product length, including: calculating the thickness change rate of the strip in the thickening section over time based on the thickness change amount at the head and tail, the head length of the thickness straight section, the tail length of the thickness straight section and the predicted finished product length; calculating the thickness change rate of the strip in the thickening section over time based on the thickness change rate of the strip in the thickening section over length and the real-time rolling speed.

[0014] In some embodiments of the present application, based on the aforementioned solution, the thickness variation rate of the strip in the thickening section along with the length is calculated based on the thickness variation of the head and tail, the length of the head of the thickness straight section, the length of the tail of the thickness straight section and the predicted finished product length, including:

[0015] The thickness variation rate of the strip steel in the thickening section along with the length is calculated according to the following formula:

[0016] rate1=Δh / (L2-l1-l2)

[0017] Among them, rate1 is the thickness change rate of the strip in the thickening section with length, Δh is the thickness change of the head and tail, l1 is the length of the head of the thickness straight section, and l2 is the length of the tail of the thickness straight section.

[0018] In some embodiments of the present application, based on the above scheme, the thickness change rate of the steel strip in the thickening section over time is calculated based on the thickness change rate of the steel strip in the thickening section over length and the real-time rolling speed, including:

[0019] The thickness change rate of the strip in the thickening section over time is calculated according to the following formula:

[0020] rate2=rate1×V

[0021] Wherein, rate2 is the thickness change rate of the strip in the thickening section with time, rate1 is the thickness change rate of the strip in the thickening section with length, and V is the real-time rolling speed.

[0022] In some embodiments of the present application, based on the aforementioned scheme, the triggering of the thickening and continuous rolling signal for the strip includes: if the head length of the strip out of the rolling mill is greater than the head length of the thickness straight section, then the thickening and continuous rolling signal for the strip is triggered.

[0023] In some embodiments of the present application, the method further includes: resetting all parameter settings after the steel strip completes hot rolling.

[0024] Based on the above solution, the technical solution provided by this application has at least the following advantages and improvements:

[0025] In this application, the thickness change rate is determined by various parameters in the rolling process and the finished product specification data, and the calculated thickness change rate is input into the hot rolling control logic. This can achieve the purpose of producing hot-rolled strip products with continuous and uniform longitudinal thickness changes without adding any hardware products and investments. It can also control the length of the head and tail thickness holding sections and the thickness change of the entire strip.

[0026] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0028] Figure 1 A simplified diagram of product requirements of a production control method for hot-rolled variable-thickness strip steel according to an embodiment of the present application is shown;

[0029] Figure 2 A simplified flow chart of a production control method for hot-rolled variable-thickness strip steel according to an embodiment of the present application is shown;

[0030] Figure 3 A simplified flow chart of a production control method for hot-rolled variable-thickness strip steel according to an embodiment of the present application is shown;

[0031] Figure 4 A simplified flow chart of a production control method for hot-rolled variable-thickness strip steel according to an embodiment of the present application is shown;

[0032] Figure 5 The actual thickness variation diagram of the production control method of hot-rolled variable-thickness strip according to one embodiment of the present application is shown. DETAILED DESCRIPTION

[0033] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be more comprehensive and complete and fully convey the concept of the example embodiments to those skilled in the art.

[0034] See also Figure 1 .

[0035] Figure 1 A product requirement diagram of a production control method for hot-rolled variable thickness strip steel according to an embodiment of the present application is shown. Figure 1 As shown, the variable wall thickness section of the innermost coil is divided into three stages: A, B, and C. Section A is a thin-walled area, section B is a thickness gradient area, and section C is a thick-walled area. Because similar products have uniform thickness changes along the length of the strip, the existing hot rolling production line can only roll strips with relatively uniform thickness, but the production control method provided by this application can be used to produce variable thickness strips.

[0036] In this application, the thickness change rate is determined by various parameters in the rolling process and the finished product specification data, and the calculated thickness change rate is input into the hot rolling control logic. This can achieve the purpose of producing hot-rolled strip products with continuous and uniform longitudinal thickness changes without adding any hardware products and investments. It can also control the length of the head and tail thickness holding sections and the thickness change of the entire strip.

[0037] See also Figure 2 .

[0038] Figure 2 A simplified flow chart of a production control method for hot-rolled variable thickness strip steel according to an embodiment of the present application is shown, and the method may include steps S201-S204:

[0039] Step S201, according to the product requirements of hot-rolled steel strip, setting the thickness variation parameter of the steel strip, wherein the thickness variation parameter is used to characterize the thickness variation during the production process of the steel strip.

[0040] Step S202, obtaining strip steel production parameters, wherein the strip steel production parameters include intermediate billet parameters, head cutting amount, tail cutting amount, finished strip steel thickness, and real-time rolling speed.

[0041] Step S203: determining the thickness change rate of the steel strip in the thickening section over time based on the thickness change parameter and the steel strip production parameter.

[0042] Step S204: after triggering a variable thickness hot rolling signal for the steel strip, performing variable thickness hot rolling according to the thickness change rate over time.

[0043] In the present application, the thickness variation parameters may include: thickness variation of the head and tail, the length of the head of the thickness straight section, and the length of the tail of the thickness straight section.

[0044] In the present application, the intermediate billet parameters may include the intermediate billet length and the intermediate billet thickness. It should be noted that the intermediate billet described in the present application is the product of the continuous casting billet after being rolled by the roughing mill, and then this product is used as a billet for the finishing mill to perform finishing rolling, so it is called an intermediate billet. The parameter data of the intermediate billet is very important for the overall hot rolling, and the frame settings of the roughing and finishing rolling often need to be designed according to the intermediate billet parameters.

[0045] See also Figure 3 .

[0046] Figure 3 A simplified flow chart of a production control method for hot-rolled variable thickness strip steel according to an embodiment of the present application is shown, as shown in FIG. Figure 3 As shown, in step S203, the method for determining the thickness change rate of the strip steel in the thickening section over time based on the thickness change parameter and the strip steel production parameter may include steps S301-S302:

[0047] Step S301, determining the predicted finished length of the strip based on the thickness variation parameter and the strip production parameter.

[0048] Step S302, based on the thickness variation parameter and the predicted finished product length, calculate the thickness variation rate of the strip in the thickening section over time.

[0049] In the present application, in step S301, the method for determining the predicted finished length of the strip steel based on the thickness variation parameter and the strip steel production parameter may include:

[0050] The predicted finished length of the strip is calculated according to the following formula:

[0051]

[0052] Among them, L2 is the predicted finished length of the strip, l1 is the head length of the thickness straight section, l2 is the tail length of the thickness straight section, L1 is the intermediate billet length of the strip, h2 is the finished strip thickness, h1 is the intermediate billet thickness, x is the head cutting amount, y is the tail cutting amount, and Δh is the thickness change of the head and tail.

[0053] See also Figure 4 .

[0054] Figure 4 A simplified flow chart of a production control method for hot-rolled variable thickness strip steel according to an embodiment of the present application is shown, as shown in FIG. Figure 4 As shown, in step S302, the method for calculating the thickness change rate of the strip in the thickening section over time based on the thickness change parameter and the predicted finished product length may include steps S401-S402:

[0055] Step S401, based on the thickness variation of the head and tail, the length of the head of the thickness straight section, the length of the tail of the thickness straight section and the predicted finished product length, calculate the thickness variation rate of the strip in the thickening section with the length.

[0056] Step S402, based on the thickness change rate of the steel strip in the thickening section with length and the real-time rolling speed, calculate the thickness change rate of the steel strip in the thickening section with time.

[0057] In the present application, in step S401, the method for calculating the thickness change rate of the strip steel in the thickening section with length based on the thickness change amount of the head and tail, the head length of the thickness straight section, the tail length of the thickness straight section and the predicted finished product length may include:

[0058] The thickness variation rate of the strip steel in the thickening section along with the length is calculated according to the following formula:

[0059] rate1=Δh / (L2-l1-l2)

[0060] Among them, rate1 is the thickness change rate of the strip in the thickening section with length, Δh is the thickness change of the head and tail, l1 is the length of the head of the thickness straight section, and l2 is the length of the tail of the thickness straight section.

[0061] In the present application, in step S402, the method for calculating the thickness change rate of the steel strip in the thickening section over time based on the thickness change rate of the steel strip in the thickening section over length and the real-time rolling speed includes:

[0062] The thickness change rate of the strip in the thickening section over time is calculated according to the following formula:

[0063] rate2=rate1×V

[0064] Wherein, rate2 is the thickness change rate of the strip in the thickening section with time, rate1 is the thickness change rate of the strip in the thickening section with length, and V is the real-time rolling speed.

[0065] In this application, the thickness change with the length of the strip can be calculated based on the thickness change parameter and the strip production parameter, that is, when rolling one meter of strip, how much the strip thickness changes. After determining the thickness change rate of the strip in the thickening section with the length, the product of the thickness change rate of the thickening section with the length and the real-time rolling speed is calculated, and it is not difficult to obtain the thickness change rate of the strip in the thickening section with time. The calculated thickness change rate can be used as the target value for the compensation of the thickness deviation over time. By tracking and judging when the length of the head mill is greater than a, rate2 is added as the AGC thickness deviation input to realize variable thickness control.

[0066] In the present application, the method for triggering the thickening and continuous rolling signal for the strip includes: if the head length of the strip out of the rolling mill is greater than the head length of the thickness straight section, triggering the thickening and continuous rolling signal for the strip.

[0067] In the present application, if the head length of the strip out of the rolling mill is greater than the head length of the thick straight section, it means that the strip has entered the thickening section and thickness control compensation is required in time to successfully roll out the strip with variable thickness.

[0068] See also Figure 5 .

[0069] Figure 5 FIG. 4 shows an actual thickness variation diagram of a production control method for hot-rolled variable-thickness strip steel according to an embodiment of the present application, such as Figure 5 As shown, after adopting the production control method provided by the present application, the thickness of the strip changes relatively evenly after entering the thickening section, indicating that hot continuous rolling of the variable thickness strip is successfully carried out.

[0070] In the present application, the method further includes: resetting all parameter settings after the strip steel is hot-rolled. After the strip steel is rolled, the steel type specifications or finished product specifications that are subsequently rolled are likely to be different, so the thickness change rate needs to be recalculated and reset according to different thickness change parameters and strip steel production parameters.

[0071] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the embodiments disclosed herein. The present application is intended to cover any variations, uses or adaptations of the present application, which follow the general principles of the present application and include common knowledge or customary technical means in the art that are not disclosed in the present application.

[0072] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A production control method for hot-rolled variable thickness strip steel, characterized in that: The method comprises: According to the product requirements of the hot-rolled strip steel, the thickness variation parameter of the strip steel is set, and the thickness variation parameter is used to characterize the thickness variation during the strip steel production process; Acquiring strip steel production parameters, wherein the strip steel production parameters include intermediate billet parameters, head cutting amount, tail cutting amount, finished strip steel thickness, and real-time rolling speed; Based on the thickness variation parameter and the strip production parameter, determining the thickness variation rate of the strip in the thickening section over time; After triggering a variable thickness continuous rolling signal for the strip, performing variable thickness hot continuous rolling according to the thickness change rate over time; The thickness variation parameters include: thickness variation of the head and tail, length of the head of the thickness straight section, and length of the tail of the thickness straight section; The step of determining the thickness change rate of the steel strip in the thickening section over time based on the thickness change parameter and the steel strip production parameter comprises: Determining a predicted finished length of the steel strip based on the thickness variation parameter and the steel strip production parameter; Based on the thickness variation parameter and the predicted finished product length, calculating the thickness variation rate of the strip in the thickening section over time; The step of determining the predicted finished length of the steel strip based on the thickness variation parameter and the steel strip production parameter comprises: The predicted finished length of the strip is calculated according to the following formula: Among them, L2 is the predicted finished length of the strip, l1 is the head length of the thickness straight section, l2 is the tail length of the thickness straight section, L1 is the intermediate billet length of the strip, h2 is the finished strip thickness, h1 is the intermediate billet thickness, x is the head cutting amount, y is the tail cutting amount, and Δh is the thickness change of the head and tail.

2. The method according to claim 1, characterized in that: The step of calculating the thickness change rate of the strip steel in the thickening section over time based on the thickness change parameter and the predicted finished product length comprises: Calculate the thickness variation rate of the strip steel in the thickening section along with the length based on the thickness variation of the head and tail, the length of the head of the thickness straight section, the length of the tail of the thickness straight section and the predicted finished product length; Based on the thickness change rate of the steel strip in the thickening section with the length and the real-time rolling speed, the thickness change rate of the steel strip in the thickening section with time is calculated.

3. The method according to claim 2, characterized in that The method of calculating the thickness variation rate of the strip steel in the thickening section along with the length based on the thickness variation of the head and tail, the length of the head of the thickness straight section, the length of the tail of the thickness straight section and the predicted finished product length comprises: The thickness variation rate of the strip steel in the thickening section along with the length is calculated according to the following formula: rate1=Δh / (L2-l1-l2) Among them, rate1 is the thickness change rate of the strip in the thickening section with length, Δh is the thickness change of the head and tail, l1 is the length of the head of the thickness straight section, and l2 is the length of the tail of the thickness straight section.

4. The method according to claim 2, characterized in that: The method of calculating the thickness change rate of the steel strip in the thickening section over time based on the thickness change rate of the steel strip in the thickening section over length and the real-time rolling speed includes: The thickness change rate of the strip in the thickening section over time is calculated according to the following formula: rate2=rate1×V Wherein, rate2 is the thickness change rate of the strip in the thickening section with time, rate1 is the thickness change rate of the strip in the thickening section with length, and V is the real-time rolling speed.

5. The method according to claim 1, characterized in that: The triggering of the thickening and continuous rolling signal for the strip steel comprises: If the head length of the strip out of the rolling mill is greater than the head length of the thickness straight section, a thickening continuous rolling signal for the strip is triggered.

6. The method according to claim 1, characterized in that The method further comprises: resetting all parameter settings after the steel strip has completed hot rolling.

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