A method for controlling the centerline deviation of the export slab through R1 automatic leveling

Abstract

The present invention discloses a method for controlling the centerline deviation of an outlet slab by automatic leveling of R1, and relates to the technical field of hot rolling rough rolling process. In view of the problem that the current hot rolling rough rolling leveling effect completely relies on manual adjustment by manual operation experience, resulting in frequent manual intervention and increased labor load, the following scheme is proposed, which includes the following steps: S1, collection and processing of the centerline deviation of the slab; S2, determination of the leveling pass; S3, determination of the leveling amount; S4, restriction conditions for the use of automatic leveling; S5, control process. The present invention is a method for automatically adjusting the deviation of the rough rolling R1 oil column to control the roller gap difference on both sides of the rolling mill before rolling the next slab, based on the centerline deviation of the last pass of the previous slab R1 detected by the width gauge at the outlet of the rough rolling mill, so as to achieve the purpose of automatically controlling the centerline deviation of the outlet slab of the next slab at the last pass of R1, so that the accuracy of plate shape leveling is uniformly improved.

Description

Technical Field

[0001] The invention relates to the technical field of hot rolling and rough rolling processes, and in particular to a method for controlling the center line deviation of an outlet slab through R1 automatic leveling. Background Art

[0002] Sickle bending is a plate shape problem that often occurs in the rough rolling area during the hot rolling production process. It is mainly caused by the uneven extension of the slab in the width direction. There are many reasons for the formation of sickle bending, including: inconsistent temperature in the width direction of the slab, inconsistent thickness of the slab due to machine cleaning, inconsistent stiffness on both sides of the rough rolling horizontal roll, mechanical clearance and other factors will cause sickle bending during slab rolling.

[0003] The formation of sickle bend can lead to a series of negative effects such as steel jamming, poor plate shape, unstable rolling, etc. At present, sickle bend occurs in the rolling process of 2250 rough rolling R1. It is mainly through manual observation of the center line deviation measured by the width gauge and the actual plate shape on site. The sickle bend is corrected by manually adjusting the roll gap on both sides of the horizontal roll. The leveling effect depends entirely on manual adjustment by manual operation experience.

[0004] 2250 hot rolling and rough rolling R1 does not have the function of automatic control of centerline deviation, and the control of plate shape still relies on manual intervention and leveling. During the rolling process, the operator observes the on-site monitoring video and QDGS centerline deviation curve, and performs corresponding leveling according to the deviation of the plate shape and combined with their own experience. Due to the influence of factors such as steel type, hardness group, specification, temperature, etc. on the centerline deviation of rough rolling during the rolling process, manual intervention is frequent and the labor load increases. The level of rough rolling operation is different, which makes the accuracy of plate shape leveling also different. Therefore, the plate shape of the rough rolling R1 outlet fluctuates greatly. If the leveling is not timely before the R2 strip is threaded, the number of R1 steel jams and collisions with the R1 and R2 side guides due to poor R1 plate shape will increase. Summary of the invention

[0005] The present invention proposes a method for controlling the centerline deviation of an outlet slab by automatic leveling of R1, which solves the problem raised in the above-mentioned background technology.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for controlling the centerline deviation of the exit slab by automatic leveling of R1, the last pass of the previous R1 is used for steel throwing;

[0008] The width gauge measures the centerline deviation of the slab;

[0009] L2 calculates the leveling amount based on the centerline deviation and the specifications of the next strip;

[0010] L2 sends the leveling amount to L1;

[0011] L1 automatically levels after SP steel throwing;

[0012] The specific steps are as follows:

[0013] S1. Determination of leveling pass: Considering the rolling stability, the first pass of R1 is selected as the leveling pass. The oil column deviation value after leveling is maintained for the other passes, and automatic leveling is not performed;

[0014] S2. Determination of leveling amount;

[0015] S3, automatic leveling commissioning restriction conditions;

[0016] S4, control process: R1 stand has no steel, 5s after the next slab comes out of SP, R1 rolling mill is set to automatically level.

[0017] As a further solution of the present invention, the centerline deviation of the slab needs to be collected and processed before step S2: the point counting rule for the centerline deviation of the R1 outlet is: exclude the first 40 points of the head, and from the 41st point, take one every 20 points, a total of 8 points, and then take 20 points. If the point data is greater than |100|, take the average of the two points before and after, and then calculate the average of these 28 points as the value of the centerline deviation of the slab R13 head.

[0018] As a further solution of the present invention, the single-side roll gap adjustment amount of the R1 rolling mill in step S2 is shown in the following formula:

[0019]

[0020] Where:

[0021] ΔGap—R1 single-side roller gap adjustment amount mm;

[0022] α—leveling influence coefficient;

[0023] |CL 13 |—the absolute value of the centerline deviation of the last pass of the previous slab R1;

[0024] K w —Width influence coefficient;

[0025] K hard —Hardness group influence coefficient;

[0026] K E —The influence coefficient of the lateral pressure of the slab.

[0027] As a further solution of the present invention, the limiting conditions of step S3 are as follows:

[0028] (1) When manual intervention is required in production, manual intervention takes precedence;

[0029] (2) When the absolute value of the centerline deviation of the previous slab R13 is less than or equal to 20 mm, the automatic leveling calculation amount is 0;

[0030] (3) If the slab thickness is less than 228 mm, the automatic leveling value is 0; if the slab thickness is between 228 and 230 mm, the leveling value is issued normally according to the calculation;

[0031] (4) When the R1 oil column deviation exceeds ±2.0 mm, the current oil column deviation value is maintained and automatic leveling is not performed;

[0032] (5) When the calculated value of the single leveling amount of R1 exceeds ±0.3mm, the function sends the value of the upper and lower limits of the calculation.

[0033] The beneficial effects of the present invention are:

[0034] The present invention discloses a method for automatically adjusting the rough rolling R1 oil column deviation to control the roll gap difference on both sides of the rolling mill before rolling the next slab through the center line deviation of the last pass of the previous slab R1 detected by a width gauge at the rough rolling mill exit, so as to achieve the purpose of automatically controlling the center line deviation of the next slab at the last pass of R1 exit, thereby reducing the influence of the changing factors such as steel type, hardness group, specification, temperature, etc. during the rolling process on the rough rolling center line deviation, avoiding frequent manual intervention, reducing the labor load, and uniformly improving the accuracy of plate shape leveling. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the calculation process of the present invention.

[0036] Figure 2 It is a control flow diagram of the present invention. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0038] Reference Figure 1-Figure 2 As shown, this embodiment provides a method for controlling the centerline deviation of the outlet slab by automatic leveling of R1, comprising the following steps:

[0039] S1. Collection and processing of centerline deviation of slab: The point counting rule for centerline deviation of R1 outlet is: exclude the first 40 points of the head, and take one point every 20 points from the 41st point, take 8 points in total, and then take 20 points. If the point data is greater than |100|, take the average of the two points before and after, and then calculate the average of these 28 points as the value of centerline deviation of slab R13 head;

[0040] S2. Determination of leveling pass: Considering the rolling stability, the first pass of R1 is selected as the leveling pass. The oil column deviation value after leveling is maintained for the other passes, and automatic leveling is not performed;

[0041] S3. Determination of leveling amount: The single-side roll gap adjustment amount of the R1 rolling mill is shown in the following formula:

[0042]

[0043] Where:

[0044] ΔGap—R1 single-side roller gap adjustment amount mm;

[0045] α—leveling influence coefficient;

[0046] |CL 13 |—the absolute value of the centerline deviation of the last pass of the previous slab R1;

[0047] K w —Width influence coefficient;

[0048] K hard —Hardness group influence coefficient;

[0049] K E —The influence coefficient of the lateral pressure of the slab;

[0050] S4. The restrictions on the use of automatic leveling are as follows:

[0051] (1) When manual intervention is required in production, manual intervention takes precedence;

[0052] (2) When the absolute value of the centerline deviation of the previous slab R13 is less than or equal to 20 mm, the automatic leveling calculation amount is 0;

[0053] (3) If the slab thickness is less than 228 mm, the automatic leveling value is 0; if the slab thickness is between 228 and 230 mm, the leveling value is issued normally according to the calculation;

[0054] (4) When the R1 oil column deviation exceeds ±2.0 mm, the current oil column deviation value is maintained and automatic leveling is not performed;

[0055] (5) When the calculated value of the single leveling amount of R1 exceeds ±0.3mm, the function sends the value of the upper and lower limits of the calculation;

[0056] S5, control process: R1 stand has no steel, 5s after the next slab comes out of SP, R1 rolling mill is set to automatically level.

[0057] Table 1 Upper and lower limits of single leveling (mm)

[0058] Limiting Upper limit Lower limit Amplitude 0.3 -0.3

[0059] In the embodiment, the value range of leveling is: the upper and lower limits of single leveling are -0.3-0.3 mm (as shown in Table 1).

[0060] like Figure 1 As shown, the calculation process is as follows:

[0061] The last pass of the previous R1 steel;

[0062] The width gauge measures the centerline deviation of the slab;

[0063] L2 calculates the leveling amount based on the centerline deviation and the specifications of the next strip;

[0064] L2 sends the leveling amount to L1;

[0065] L1 performs automatic leveling after SP steel casting.

[0066] like Figure 2 As shown, the last pass of the previous piece R1 is used to calculate the leveling amount of the next piece; after the next piece SP is cast, R1 performs automatic leveling.

[0067] Example:

[0068] The following is an example of the calculation process of automatic leveling:

[0069] ①After 214270600800 rolling, the centerline deviation at the exit of R13 pass was -38mm. Since it exceeded the target setting range, the next strip needed to be leveled;

[0070] ② The strip number of the next strip is 214270601500. The model will automatically collect the SFC01, hardness group, temperature, thickness, width and centerline deviation value of the previous strip during the leveling amount calculation process. The calculated leveling amount is 0.28mm, and then it is issued;

[0071] ③ After rolling, since the centerline deviation of the R13 pass is 29mm, which exceeds the target setting range, the next strip 214270702200 repeats the same process, and the calculated leveling amount is -0.18mm, and it is sent out normally;

[0072] ④ After rolling, the centerline deviation of the R13 pass is 5mm, which is within the set target range, so the leveling amount calculated for the next strip 214270702000 is 0;

[0073] The above is the entire calculation and control process of R1 automatic leveling.

[0074] After the previous strip is rolled, the model calculates the centerline deviation of the head of the R13 pass;

[0075] When the centerline deviation is within the given interval (-20,20), the leveling amount of the next strip is calculated and issued as 0;

[0076] When the centerline deviation is not within the given interval (-20, 20), the model obtains the attribute width, hardness group and E1 width reduction of the next strip, and combines the difference between the head centerline deviation of the previous strip R13 pass and the target value, and calculates the leveling amount of R1 calculation when the next strip is rolled according to the model formula;

[0077] When the calculated leveling amount is within the limit (-0.3, 0.3) set by the model, the leveling amount value is sent normally; when it exceeds the limit, the leveling amount value sent is the corresponding upper and lower limits.

[0078] The working principle of the present invention is: through the slab centerline deviation detected by the rough rolling mill exit width gauge, the average of the slab head centerline deviation is calculated by eliminating abnormal points and taking points at a fixed distance, and after the average of the slab head centerline deviation is obtained, it is compared with the established R1 exit centerline deviation target value interval, so as to adjust the single-sided roll gap of the next block R1, and the adjustment direction is: if the centerline deviation of the last pass of the previous slab R1 is smaller than the target value interval, the pressing roll gap is adopted; if it is larger than the target value, the lifting roll gap is adopted.

[0079] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for controlling the centerline deviation of the export slab by automatic leveling of R1. It is characterized in that The last pass of the previous R1 steel is cast; The width gauge measures the centerline deviation of the slab; L2 calculates the leveling amount based on the centerline deviation and the specifications of the next strip; L2 sends the leveling amount to L1; L1 automatically levels after SP steel throwing; The specific steps are as follows: S1. Determination of leveling pass: Considering the rolling stability, the first pass of R1 is selected as the leveling pass. The oil column deviation value after leveling is maintained for the other passes, and automatic leveling is not performed; S2. Determination of leveling amount; S3, automatic leveling commissioning restriction conditions; S4, control process: R1 stand has no steel, 5s after the next slab comes out of SP, R1 rolling mill is set to automatically level; The single-side roll gap adjustment amount of the R1 rolling mill in step S2 is shown in the following formula: Where: —R1 single-side roller gap adjustment amount mm; —Leveling influence coefficient; —The absolute value of the centerline deviation of the last pass of the previous slab R1; —Width influence coefficient; —Hardness group influence coefficient; —The influence coefficient of the lateral pressure of the slab; The limiting conditions of step S3 are as follows: (1) When manual intervention is required in production, manual intervention takes precedence; (2) When the absolute value of the centerline deviation of the last pass of the previous slab R1 is less than or equal to 20 mm, the automatic leveling calculation amount is 0; (3) If the slab thickness is less than 228 mm, the automatic leveling value is 0; if the slab thickness is between 228 and 230 mm, the leveling value is issued normally according to the calculation; (4) When the R1 oil column deviation exceeds ±2.0 mm, the current oil column deviation value is maintained and automatic leveling is not performed; (5) When the calculated value of the single leveling amount of R1 exceeds ±0.3mm, the function sends the value of the upper and lower limits of the calculation.

2. A method for controlling the centerline deviation of an outlet slab by R1 automatic leveling according to claim 1, It is characterized in that Before step S2, the centerline deviation of the slab needs to be collected and processed: the point counting rule for the R1 outlet centerline deviation is: exclude the first 40 points of the head, and from the 41st point, take one every 20 points, a total of 8 points, and then take 20 points. If the point data is greater than |100|, take the average of the two points before and after, and then calculate the average of these 28 points as the value of the centerline deviation of the slab R13 head.

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