Monitoring and inhibiting method for head warping and buckling of medium-thickness plate

Abstract

The invention relates to a monitoring and restraining method for head warping and head buckling of a medium-thickness plate. The method comprises the steps that S1, the maximum head bending height m and the bending length L of the rolled medium-thickness plate and the bending included angle theta formed by the medium-thickness plate and a conveying roller way are monitored through a visual monitoring device; s2, when the maximum bending height m of the head of the medium-thickness plate is smaller than or equal to 50 mm, the medium-thickness plate is fed into a pre-straightening machine to be straightened for the first time; when the head of the medium-thickness plate is bent to the maximum height mgt; and when the thickness is 50 mm, the medium-thickness plate is fed into a pre-straightening machine to be subjected to Z-shaped back straightening. A visual monitoring device is used for monitoring the head warping and buckling condition in real time, whether Z-shaped return correction is carried out or not is judged according to monitored related data of the head warping and buckling, in the Z-shaped return correction process, when a medium-thickness plate reaches the L / 2 position of a pre-straightening machine, the medium-thickness plate serves as the turning point of Z-shaped return correction, the production efficiency of the plate is remarkably improved, the product yield is improved, the straightening time is synchronously prevented from being too long, and the product quality is improved. And the cold starting time is influenced.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical industry, and in particular to a method for monitoring and suppressing buckle heads of medium and thick plates. Background Art

[0002] In the production process of medium and thick plates, under normal conditions, the steel plates enter the pre-straightening machine after being rolled by the rolling mill, and then enter ultra-fast cooling after leveling. The start cooling temperature involved is the key factor.

[0003] However, when buckle heads appear in the last rolling pass, preheat straightening needs to open the roll gap where the steel plate can pass through to perform back-straightening operation to reduce the buckle head phenomenon. The back-straightening operation usually needs to be performed manually, and the size of the roll gap needs to be calculated manually. The whole back-straightening process takes a long time to execute, which will seriously affect the key process execution point of the cooling temperature.

[0004] At the same time, during the rolling process, the operator cannot observe the buckle on the steel plate at the first time. Summary of the invention

[0005] The purpose of the present invention is to provide a method for monitoring and suppressing buckle heads of medium and thick plates, which effectively controls the buckle heads of medium and thick plates during the rolling process.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: The present invention provides a method for monitoring and suppressing buckle heads of medium and thick plates, comprising the following steps: S1: monitoring the maximum head deflection height m, deflection length L and deflection angle θ formed between the medium and thick plate and the conveying roller after the medium and thick plate is rolled by a visual monitoring device; S2: When the maximum deflection height of the head of the medium and thick plate is m≤50mm, the medium and thick plate is sent to the pre-straightening machine for primary straightening; when the maximum deflection height of the head of the medium and thick plate is m>50mm, the medium and thick plate is sent to the pre-straightening machine for "Z" shape back straightening; The "Z"-shaped correction includes the following steps: (1) adjusting the gap between the straightening rollers of the pre-straightening machine to (m+50) mm; (2) feeding the medium and thick plate into the pre-straightening machine of step (1); when the head of the medium and thick plate reaches the center position L / 2 of the pre-straightening machine, pressing down the straightening roller gap of the pre-straightening machine in step (1) until the gap between the straightening rollers reaches the initial gap between the straightening rollers, and then withdrawing the medium and thick plate from the pre-straightening machine; (3) The medium and thick plate that has been straightened in step (2) is sent back into the pre-straightening machine for secondary straightening, thereby completing the "Z"-shaped straightening.

[0007] Furthermore, in step S1, the visual monitoring device is arranged at the side of the transmission roller between the rolling mill and the pre-straightening machine.

[0008] Furthermore, when it is monitored that three or more consecutive medium and thick plates have lifted heads, the odd-numbered rolling passes in the rolling process are reduced by one, and the rolling reduction of the remaining rolling passes is increased simultaneously, so that the medium and thick plates are skipped through the last reduced rolling pass, that is, the finished product is produced in the even pass.

[0009] Furthermore, when the thickness of the medium and thick plate is greater than 50 mm, it is only necessary to monitor the maximum head deflection height m of the medium and thick plate after rolling.

[0010] Furthermore, when the thickness of the medium and thick plate is ≤50 mm, if the deflection angle θ formed by the medium and thick plate and the conveying roller is greater than 30° during monitoring, the visual monitoring device will issue an alarm indicating a high degree of warping.

[0011] Furthermore, after the medium and thick plates are rolled and straightened in sequence, the process also includes rapidly cooling the medium and thick plates.

[0012] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art: The present invention arranges a visual monitoring device to monitor the buckle head condition after the rolling of the medium and thick plates in real time, obtains the corresponding head maximum deflection height m, deflection length L and deflection angle θ formed by the medium and thick plates and the transmission roller, and suppresses the buckle head based on the obtained data to improve the production yield of the medium and thick plates. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Hereinafter, some specific embodiments of the present invention will be described in detail in an exemplary and non-limiting manner with reference to the accompanying drawings. The same reference numerals in the accompanying drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the accompanying drawings: Figure 1 It is a schematic diagram of the maximum deflection height m, the deflection length L, and the deflection angle θ formed by the medium and thick plate and the transmission roller in a method for monitoring and suppressing buckle heads of medium and thick plates of the present invention; Figure 2 The process flow diagram of a method for monitoring and suppressing buckle heads of medium and thick plates according to the present invention (I) is shown; Figure 3 This is a process flow chart (II) of a method for monitoring and suppressing buckle heads of medium and thick plates according to the present invention. DETAILED DESCRIPTION

[0014] The technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] The method for monitoring and suppressing buckle heads of medium and thick plates provided in the present invention comprises the following steps: S1: Monitor the maximum head deflection height m, deflection length L and deflection angle θ formed between the medium and thick plate and the conveying roller after rolling by visual monitoring device (see Figure 1 shown); S2: When the maximum head deflection height of the monitored medium and thick plate is m≤50mm, the medium and thick plate is sent to the pre-straightening machine for primary straightening; when the maximum head deflection height of the monitored medium and thick plate is m>50mm, the medium and thick plate is sent to the pre-straightening machine for "Z" shape return straightening.

[0016] Specifically, in the prior art, the rolling production of steel plates includes rolling, straightening and rapid cooling processes. In the embodiment of the present invention, the visual monitoring device provided in step S1 is provided at the side of the transmission roller between the rolling mill and the pre-straightening machine, so as to monitor the relevant data when the medium and thick plates produce buckle heads after rolling. The visual monitoring device is respectively connected to the control end signals of the rolling mill and the pre-straightening machine, and the various data obtained by monitoring are fed back to the rolling mill and the pre-straightening machine, thereby establishing a mechanism to suppress buckle heads.

[0017] Regarding the above-mentioned suppression mechanism, specifically, when the above-mentioned visual monitoring device detects that the maximum head deflection height m of the aforementioned medium and thick plate is ≤50mm, that is, when the monitored maximum head deflection height m of the medium and thick plate is within the controllable range, the medium and thick plate can be directly sent to the pre-straightening machine for one straightening, and no additional operation is required for the medium and thick plate. When the above-mentioned visual monitoring device detects that the maximum head deflection height m of the aforementioned medium and thick plate is >50mm, the medium and thick plate needs to be sent to the pre-straightening machine for "Z"-shaped return straightening. In addition, it should be noted that in the process of transmitting the medium and thick plate from the rolling mill to the pre-straightening machine, height detection instability caused by the plate surface hitting the transmission roller is bound to occur. When this happens, the highest point detected is used as the warping height value.

[0018] Regarding the above-mentioned "Z"-shaped back-straightening, the so-called "Z"-shaped back-straightening is to use the medium and thick plates to perform back-and-forth straightening in the pre-straightening machine to eliminate the buckle head phenomenon. For details, refer to Figure 2 and Figure 3When the visual monitoring device detects that the maximum bending height of the head of the aforementioned medium and thick plate is m>50mm, the visual monitoring device will send a signal to the control end of the pre-straightening machine, and the pre-straightening machine will adjust the gap of the straightening roller to (m+50)mm to ensure that the medium and thick plate with buckled heads can enter the pre-straightening machine safely. When the head of the medium and thick plate moves to L / 2 of the pre-straightening machine, the pre-straightening machine will press down the gap of the straightening roller to the initial gap state. With the help of the downward pressure of the gap of the straightening roller, the buckled heads of the medium and thick plates are pre-treated.

[0019] After the straightening rollers are pressed down, the plate is withdrawn from the pre-straightening machine. After the plate is completely withdrawn from the pre-straightening machine, it is sent to the pre-straightening machine for secondary straightening, thus completing the so-called "Z" shape return straightening.

[0020] As for why the medium and thick plates are withdrawn from the pre-straightening machine when they reach L / 2 of the pre-straightening machine, the reason is that the medium and thick plates need to be cooled quickly after rolling and straightening, and the cooling temperature during cooling is a key control factor affecting the transformation of the plate structure. The cooling temperature directly affects the processing performance, structure and performance of the final product of the plate, so the cooling temperature needs to be strictly controlled. In order to prevent the cooling temperature from affecting the defective rate of the product, the medium and thick plates are withdrawn when they reach L / 2 of the pre-straightening machine in the embodiment of the present invention.

[0021] In the embodiment of the present invention, when the aforementioned visual monitoring device detects that there are three or more consecutive buckled heads on the medium and thick plates, the visual monitoring device will alarm. At this time, the continuous buckled head phenomenon can be solved by adjusting the relevant operating conditions in the rolling process. Specifically, in the embodiment of the present invention, the odd number of rolling passes of the original rolling process is reduced by one rolling pass, and the reduction amount of the remaining rolling passes is increased simultaneously. After the medium and thick plates are rolled by the rolling passes with increased reduction amount, the above-mentioned reduced rolling passes are skipped, so that the buckled heads of the medium and thick plates are transferred from the original head of the plate to the tail of the plate. In this way, by adjusting the corresponding operating conditions in the rolling process, the head of the medium and thick plate can smoothly enter the pre-straightening machine, and the buckled heads at the tail will be straightened by the pre-straightening machine. The size of the reduction amount of the specific rolling pass is reasonably arranged according to the thickness of the medium and thick plate and the actual production needs.

[0022] In addition, in the embodiment of the present invention, when the thickness of the medium and thick plate is greater than 50 mm, it is only necessary to monitor the maximum head deflection height m of the medium and thick plate after rolling, and directly control it by the deflection height m. When the thickness of the medium and thick plate is ≤ 50 mm, if the deflection angle θ formed by the medium and thick plate and the conveying roller is greater than 30° during monitoring, the visual monitoring device will issue a high warping alarm to remind the operator to intervene.

[0023] In summary, the present invention provides a monitoring and suppression method for the warped heads of medium and thick plates. The visual monitoring device is used to monitor the warped heads in real time. The "Z" shape return straightening is determined based on the monitored warped head related data. In the "Z" shape return straightening process, the arrival of the medium and thick plate at the L / 2 position of the pre-straightening machine is used as the turning point of the "Z" shape return straightening, which significantly improves the production efficiency of the plate, improves the product quality rate, and simultaneously avoids the straightening time being too long, which affects the timing of starting the cold run.

[0024] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the contents of the present invention and implement them accordingly. They cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for monitoring and suppressing buckle heads on medium and thick plates, characterized in that: The steps include: S1: monitoring the maximum head deflection height m, deflection length L and deflection angle θ formed between the medium and thick plate and the conveying roller after the medium and thick plate is rolled by a visual monitoring device; S2: When the maximum deflection height of the head of the medium and thick plate is m≤50mm, the medium and thick plate is sent to the pre-straightening machine for primary straightening; when the maximum deflection height of the head of the medium and thick plate is m>50mm, the medium and thick plate is sent to the pre-straightening machine for "Z" shape return straightening; The "Z" shape back-correction comprises the following steps: (1) adjusting the gap between the straightening rollers of the pre-straightening machine to (m+50) mm; (2) feeding the medium and thick plate into the pre-straightening machine of step (1); when the head of the medium and thick plate reaches the center position L / 2 of the pre-straightening machine, pressing down the straightening roller gap of the pre-straightening machine in step (1) until the gap between the straightening rollers reaches the initial gap between the straightening rollers, and then withdrawing the medium and thick plate from the pre-straightening machine; (3) The medium and thick plate that has been straightened in step (2) is sent back into the pre-straightening machine for secondary straightening, thereby completing the "Z"-shaped straightening.

2. A method for monitoring and suppressing buckle heads on medium and thick plates according to claim 1, characterized in that: In step S1, the visual monitoring device is arranged at the side of the transmission roller table between the rolling mill and the pre-straightening machine.

3. The method for monitoring and suppressing buckle heads of medium and thick plates according to claim 1 is characterized in that: When it is monitored that three or more consecutive medium and thick plates have buckled heads, the odd-numbered rolling passes in the rolling process are reduced by one, and the rolling reduction of the remaining rolling passes is increased simultaneously, and the medium and thick plates are allowed to pass through the last reduced rolling pass without any rotation.

4. The method for monitoring and suppressing buckle heads of medium and thick plates according to claim 1 is characterized in that: When the thickness of the medium and thick plate is greater than 50 mm, it is only necessary to monitor the maximum head deflection height m of the medium and thick plate after rolling.

5. The method for monitoring and suppressing buckle heads of medium and thick plates according to claim 1 is characterized in that: When the thickness of the medium and thick plate is ≤50 mm, if the bending angle θ formed by the medium and thick plate and the conveying roller is greater than 30° during monitoring, the visual monitoring device will issue a high warping degree alarm.

6. The method for monitoring and suppressing buckle heads of medium and thick plates according to claim 1 is characterized in that: After the medium and thick plates are rolled and straightened in sequence, the method further includes rapidly cooling the medium and thick plates.

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