Method for controlling thickness of hot-rolled wheel steel oxide scale

Abstract

The invention discloses a hot-rolled wheel steel oxide scale thickness control method and belongs to the technical field of steel rolling control methods. According to the technical scheme, the method comprises the steps of S1, collecting current rolled piece data; s2, the thickness of the third scale of the finished strip steel is pre-calculated, and if the thickness of the third scale meets the requirement of the thickness of the scale, the step S3 is executed; if not, executing the step S4; s3, the rolling piece is rolled into a finished product through the finishing mill, and the step S6 is executed; s4, the starting number of cooling water between the racks of the finishing mill is judged, if the cooling water is not completely started, a set of cooling water between the racks is added, and the step S3 is executed; if all, starting and executing the step S5; s5, activating an oscillation mode, oscillating the rolled piece on a roller way between rough rolling and finish rolling, and turning to the step S3; s6, collecting the actual data of the finished strip steel, calculating the thickness of the third-time oxide scale, and normally releasing if the requirement is met; and if not, identifying and alarming. According to the method, the thickness of the oxidized scale of the finished strip steel is dynamically controlled through feedback adjustment of the online piece rolling process.

Description

Technical Field

[0001] The invention relates to a method for controlling the thickness of hot-rolled wheel steel oxide scale, belonging to the technical field of steel rolling control methods. Background Art

[0002] The structure of a steel automobile wheel consists of a rim and a spoke. The spoke and rim are obtained by a series of strict manufacturing processes such as spinning (rolling) forming, welding, pickling, etc. of steel plates. Therefore, the hot-rolled raw steel plates used to make wheels must have high surface quality in addition to good plasticity and welding formability. This is because the tertiary iron scale that must exist on the surface of the hot-rolled plate has a great influence on the processing procedures of steel wheels. On the one hand, the thicker iron scale has poor conductivity, affects the welding quality, and easily causes cracking in the forming process; on the other hand, the thicker iron scale is easy to adhere to the mold during the forming process, causing scratches or indentations on the surface of the workpiece, affecting the appearance quality of the product; in addition, the thicker tertiary iron scale on the surface of the hot-rolled plate will increase the acid consumption in the downstream pickling process, which is not conducive to environmental protection and yield rate. In order to eliminate the influence of the tertiary iron scale of the hot-rolled plate, the wheel processing plant will shot blast or pickle the hot-rolled raw steel plate, which not only increases the process cost, but also pollutes the environment. Therefore, the control of the tertiary iron scale on the surface of the hot-rolled plate is of great significance for actual production.

[0003] At present, the research on the control of scale oxide is focused on the optimization of the rolling process, but the rolling process is not stable, which will inevitably affect the stable control of the scale oxide on the surface of the final hot-rolled plate. There are also studies that predict the scale oxide of the hot-rolled finished strip, and then make corrections to the hot rolling process, or provide guidance for the adjustment of the downstream processing pickling process. For example, in Chinese Patent Application No. 202111003531.2 "A method for predicting the characteristics of scale oxide on the surface of hot-rolled strip", the thickness of the finished scale oxide is calculated based on the final rolling temperature and coiling temperature, but the key factor affecting the thickness of the scale oxide - oxidation time is missing, and it can only be predicted but not dynamically adjusted online; in Chinese Patent Application No. 201010209526.2 "A soft measurement method for the thickness of scale oxide on the surface of hot-rolled strip", the thickness of the scale oxide is predicted by establishing a soft measurement model under variable temperature conditions. The model requires the process parameters after rolling as input, and cannot predict the scale oxide in advance, nor can it dynamically control the scale oxide thickness online. Summary of the invention

[0004] The purpose of the present invention is to provide a method for controlling the oxide scale thickness of hot-rolled wheel steel. By using the big data regression method, an accurate regression equation for the oxide scale thickness of the finished product is established, and the oxide scale thickness of the finished strip steel is predicted in advance by setting parameters as input items. By feedback adjustment of the process technology of the online rolled piece, the oxide scale thickness of the finished strip steel is dynamically controlled, effectively solving the above-mentioned problems existing in the background technology.

[0005] The technical solution of the present invention is: a method for controlling the thickness of oxide scale of hot-rolled wheel steel, comprising the following steps:

[0006] S1. After the rolled piece is rolled in the final rough rolling pass and tested by a pyrometer at the rough rolling exit, the current rolled piece data is collected;

[0007] S2, pre-calculate the tertiary oxide scale thickness of the finished strip steel. If it meets the requirements for the oxide scale thickness, it is judged to be yes, and step S3 is executed; if it does not meet the requirements for the oxide scale thickness, it is judged to be no, and step S4 is executed;

[0008] S3, the finishing mill rolls the rolled piece into a finished product, and then goes to step S6;

[0009] S4, judging the number of cooling water between the racks of the finishing mill, if not all of them are turned on, adding one group in the order from front to back based on the default number of cooling water between the racks, and going to step S3; if all of them are turned on, going to step S5;

[0010] S5, activating the oscillation mode, the rolled piece oscillates on the roller table between rough rolling and finish rolling for 10 seconds, and then goes to step S3;

[0011] S6. Collect the actual data of finished steel strips, calculate the tertiary oxide scale thickness of finished steel strips, and release them normally if they meet the requirements; if they do not meet the requirements, mark them as alarms and go through the review process.

[0012] In step S2, the formula for precalculating the thickness δ of the tertiary oxide scale of the finished strip steel is:

[0013] δ=0.316*H+0.0888*FDT-0.879*Vt-C

[0014] Wherein, 64≤C≤65; H is the target thickness of the finished product, in mm; FDT is the final rolling temperature, in °C; Vt is the final stand finishing rolling speed, in m / s.

[0015] In the formula, C=64.8.

[0016] In step S2, the thickness of the oxidized iron sheet is determined by the thickness H of the finished product. When H is less than 6.0 mm, the upper limit of the thickness of the oxidized iron sheet is δ t =7.5μm; when 6≤H<10.0mm,δt =9μm; when H≥10.0mm, δ t =12μm.

[0017] In the step S1, the current rolled piece data includes the set final stand finishing rolling threading speed, the target thickness of the finished product and the set final rolling temperature of the current rolled piece.

[0018] In step S6, the actual data of the finished steel strip includes the actual final stand finishing rolling speed of the finished steel strip, the target thickness of the finished product and the actual final rolling temperature.

[0019] The beneficial effects of the present invention are as follows: by using the big data regression method to establish an accurate regression equation for the thickness of the finished iron oxide scale, the set parameters are used as input items to predict the thickness of the iron oxide scale of the finished steel strip in advance, and the thickness of the iron oxide scale of the finished steel strip is dynamically controlled by feedback adjustment of the process technology of the online rolled piece. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the invention implementation cases clearer, the technical solutions in the implementation cases of the present invention will be clearly and completely described below in conjunction with the drawings in the implementation cases. Obviously, the implementation cases described are only a small part of the implementation cases of the present invention, rather than all the implementation cases. Based on the implementation cases in the present invention, all other implementation cases obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0022] A method for controlling the thickness of hot-rolled wheel steel oxide scale comprises the following steps:

[0023] S1. After the rolled piece is rolled in the final rough rolling pass and tested by a pyrometer at the rough rolling exit, the current rolled piece data is collected;

[0024] S2, pre-calculate the tertiary oxide scale thickness of the finished strip steel. If it meets the requirements for the oxide scale thickness, it is judged to be yes, and step S3 is executed; if it does not meet the requirements for the oxide scale thickness, it is judged to be no, and step S4 is executed;

[0025] S3, the finishing mill rolls the rolled piece into a finished product, and then goes to step S6;

[0026] S4, judging the number of cooling water between the racks of the finishing mill, if not all of them are turned on, adding one group in the order from front to back based on the default number of cooling water between the racks, and going to step S3; if all of them are turned on, going to step S5;

[0027] S5, activating the oscillation mode, the rolled piece oscillates on the roller table between rough rolling and finish rolling for 10 seconds, and then goes to step S3;

[0028] S6. Collect the actual data of finished steel strips, calculate the tertiary oxide scale thickness of finished steel strips, and release them normally if they meet the requirements; if they do not meet the requirements, mark them as alarms and go through the review process.

[0029] In step S2, the formula for precalculating the thickness δ of the tertiary oxide scale of the finished strip steel is:

[0030] δ=0.316*H+0.0888*FDT-0.879*Vt-C

[0031] Wherein, 64≤C≤65; H is the target thickness of the finished product, in mm; FDT is the final rolling temperature, in °C; Vt is the final stand finishing rolling speed, in m / s.

[0032] In the formula, C=64.8.

[0033] In step S2, the thickness of the oxidized iron sheet is determined by the thickness H of the finished product. When H is less than 6.0 mm, the upper limit of the thickness of the oxidized iron sheet is δ t =7.5μm; when 6≤H<10.0mm,δ t =9μm; when H≥10.0mm, δ t =12μm.

[0034] In the step S1, the current rolled piece data includes the set final stand finishing rolling threading speed, the target thickness of the finished product and the set final rolling temperature of the current rolled piece.

[0035] In step S6, the actual data of the finished steel strip includes the actual final stand finishing rolling speed of the finished steel strip, the target thickness of the finished product and the actual final rolling temperature.

[0036] In practical application, the present invention comprises the following steps:

[0037] S1. After the rolled piece is rolled in the final rough rolling pass and tested by the rough rolling exit pyrometer, the set final stand finishing rolling threading speed, the target thickness of the finished product and the set final rolling temperature data of the rolled piece are collected;

[0038] S2. Use the following formula (1) to calculate the thickness of the oxide scale, such as δ-δ t <0, execute step S3; if δ-δ t ≥0, execute step S4;

[0039] δ =0.316*H+0.0888*FDT-0.879*V t -C (1)

[0040] In formula (1), 64≤C≤65; H is the target thickness of the finished product, in mm; FDT is the final rolling temperature, in °C; V t It is the strip threading speed of the final stand finishing rolling, in m / s.

[0041] S3, the finishing mill rolls the rolled piece into a finished product, and then goes to step S6;

[0042] S4, judging the number of cooling water between the racks of the finishing mill, if not all are turned on, the cooling water between the racks is increased by one group in the order from front to back based on the default opening number, and going to step S3; if all are turned on, going to step S5;

[0043] S5, activating the oscillation mode, the rolled piece oscillates on the roller table between rough rolling and finish rolling for 10 seconds, and then goes to step S3;

[0044] S6. Collect the actual final stand finishing rolling speed, target thickness and actual final rolling temperature data of the finished strip, and use formula (1) to calculate the tertiary oxide scale thickness of the finished strip, such as δ-δ t <0, normal release; such as δ-δ t ≥0, the alarm will go through the review process;

[0045] where δ t The upper limit of the thickness of the oxidized iron sheet is determined by the thickness of the finished product H. When H is less than 6.0 mm, the upper limit of the thickness of the oxidized iron sheet is δ t =7.5μm; when 6≤H<10.0mm,δ t =9μm; when H≥10.0mm, δ t =12μm.

[0046] Examples 1-9 were produced according to the above-mentioned implementation method, see Table 1.

[0047] Table 1

[0048]

[0049]

[0050] The above embodiments are only used to illustrate rather than limit the technical solutions of the present invention. Although the present invention is described in detail with reference to the above embodiments, those skilled in the art should understand that the present invention can still be modified or replaced by equivalents. Any modification or partial replacement that does not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A method for controlling the thickness of hot-rolled wheel steel oxide scale, characterized in that The following steps are involved: S1. After the rolled piece is rolled in the final rough rolling pass and tested by a pyrometer at the rough rolling exit, the current rolled piece data is collected; S2, pre-calculate the tertiary oxide scale thickness of the finished strip steel. If it meets the requirements for the oxide scale thickness, it is judged as yes, and step S3 is executed; if it does not meet the requirements for the oxide scale thickness, it is judged as no, and step S4 is executed; S3, the finishing mill rolls the rolled piece into a finished product, and then goes to step S6; S4, judging the number of cooling waters between the racks of the finishing mill that are turned on, if not all of them are turned on, adding one group in the order from front to back based on the default number of cooling waters between the racks, and going to step S3; If all are enabled, proceed to step S5; S5, activating the oscillation mode, the rolled piece oscillates on the roller table between rough rolling and finish rolling for 10 seconds, and then goes to step S3; S6. Collect the actual data of finished steel strips, calculate the tertiary oxide scale thickness of finished steel strips, and release them normally if they meet the requirements; if they do not meet the requirements, mark them as alarms and go through the review process.

2. The method for controlling the thickness of hot-rolled wheel steel oxide scale according to claim 1, characterized in that: In step S2, the formula for precalculating the thickness δ of the tertiary oxide scale of the finished strip steel is: δ =0.316×H+0.0888×FDT-0.879×Vt-C Wherein, 64≤C≤65; H is the target thickness of the finished product, in mm; FDT is the final rolling temperature, in °C; Vt is the final stand finishing rolling speed, in m / s.

3. The method for controlling the thickness of hot-rolled wheel steel oxide scale according to claim 2, characterized in that: In the formula, C=64.

8.

4. The method for controlling the thickness of hot-rolled wheel steel oxide scale according to claim 1, characterized in that: In step S2, the thickness of the oxidized iron sheet is determined by the thickness H of the finished product. When H is less than 6.0 mm, the upper limit of the thickness of the oxidized iron sheet is δ t =7.5μm; when 6≤H<10.0mm, δ t =9μm; when H≥10.0mm, δ t =12μm.

5. The method for controlling the thickness of hot-rolled wheel steel oxide scale according to claim 1, characterized in that: In the step S1, the current rolled piece data includes the set final stand finishing rolling threading speed, the target thickness of the finished product and the set final rolling temperature of the current rolled piece.

6. The method for controlling the thickness of hot-rolled wheel steel oxide scale according to claim 1, characterized in that: In step S6, the actual data of the finished steel strip includes the actual final stand finishing rolling speed of the finished steel strip, the target thickness of the finished product and the actual final rolling temperature.

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