A method for controlling the full multiple length of bars in a steelmaking and rolling combined process

Abstract

The present application relates to the field of metallurgical engineering technology, and specifically to a method for controlling the full-length length of a bar in a steelmaking and rolling combined process, comprising: step 1, shearing the bar rolled from the billet with a flying shear, and measuring the length of the last section of the bar; step 2, calculating the difference between the length of the last section of the bar and the full-length bar length; step 3, changing the length of the billet in the billet shearing stage according to the difference between the length of the last section of the bar and the full-length bar length. The present invention can more effectively control the final length of the bar, reduce length deviation, reduce waste generation and the necessity of subsequent trimming, reduce production costs, shorten production cycles, and improve overall production efficiency by making adjustments in the steelmaking stage.

Description

Technical Field

[0001] The present application relates to the field of metallurgical engineering technology, and in particular to a method for controlling the full multiple length of a bar in a steelmaking and rolling combined process. Background Art

[0002] The close integration of steelmaking and rolling processes reduces intermediate links, avoids multiple heating, transportation and waiting time, improves overall production efficiency and shortens the production cycle. This integrated production method has been widely used in the modern steel industry.

[0003] Steelmaking and steel rolling are important processes that directly affect the quality and production efficiency of steel. How to improve the yield rate of steel, reduce waste, and improve production efficiency during the production process is one of the focus issues for enterprises. The production of bars involves a complex process, among which how to accurately control the length of the bars, especially to meet the full-length standard, is an important link to ensure product quality and improve production efficiency.

[0004] The traditional method of controlling the length of bars mainly relies on post-rolling shearing technology, that is, the shearing operation of the flying shear during the rolling process is used to obtain the bar length that meets the requirements. However, the length of the bar after the flying shear is sheared does not always meet the full-scale requirements. The influencing factors are complex, including rolling speed, billet temperature, timing of the flying shear action, etc. Due to the influence of these factors, the length of the bar is often short or long, affecting the yield rate. In order to deal with these problems, the industry compensates for the length deviation through subsequent trimming or waste reprocessing, but these measures not only increase production costs, but also extend the production cycle and reduce overall production efficiency.

[0005] In the combined process of steelmaking and steel rolling, the steel billets formed by steelmaking are not easy to weigh directly. Therefore, how to effectively control the full-scale length of the bars in the combined process of steelmaking and steel rolling, reduce the generation of waste, and optimize the production process has become a technical problem that needs to be solved urgently. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a method for controlling the full multiple length of a bar in a steelmaking and rolling combined process, comprising the following steps:

[0007] Step 1: Use a flying shear to cut the bars rolled from the billet and measure the length of the last section of the bars;

[0008] Step 2, calculating the difference between the length of the last section of the bar and the length of the full-length bar;

[0009] Step 3: According to the difference between the length of the last section of the bar and the length of the full-length bar, the length of the billet is changed during the billet shearing stage.

[0010] The core concept of the present invention is to accurately control the length of the bar by adjusting the length of the billet during the billet shearing stage, thereby ensuring that the bar can meet the full-length requirements during the rolling process. Specifically, during the bar rolling process, the length of the last section of the bar is measured, and the difference between it and the target full-length length is calculated. Based on the difference, the length of the billet is changed during the billet shearing stage to compensate for the length error that may occur during the rolling process. This method improves the accuracy of bar length control through source adjustment, reduces the generation of waste, optimizes the production process, and improves production efficiency and yield rate.

[0011] Furthermore, in step 1, a first length measuring instrument and a second length measuring instrument are respectively arranged at the input end and the end of the cooling bed, and the length of the last section of the bar is calculated by the distance between the first length measuring instrument and the second length measuring instrument, the distance between the tail end of the last section of the bar and the first length measuring instrument, and the distance between the beginning of the last section of the bar and the second length measuring instrument. By respectively arranging the first length measuring instrument and the second length measuring instrument at the input end and the end of the cooling bed, the length of the last section of the bar can be measured more accurately. Combining the data of multiple measurement points to calculate the length can reduce the error that may exist in a single measurement point and improve the accuracy of the measurement result. In addition, by using the measurement data of two length measuring instruments at the same time, the measurement error caused by factors such as the position change and bending of the bar can be effectively reduced, thereby better reflecting the actual length of the bar.

[0012] Furthermore, in step 2, the difference between the length of the last section of the bar and the full-length bar length is equal to the full-length bar length minus the length of the last section of the bar. Through this calculation, the difference between the actual production bar length and the target full-length length is directly obtained, and the length deviation in the current production process is understood, so as to take corresponding adjustment measures in the next step.

[0013] Furthermore, in step 3, the mass of the steel billet corresponding to the increased length of the steel billet is equal to the difference between the length of the last section of the bar and the length of the full-length bar multiplied by the mass of the bar per unit length. The mass of the bar per unit length is calculated based on previous data. In this way, the mass of the steel billet that needs to be increased is calculated. The previous data refers to the data of bars refined and rolled under the same process within a short time interval.

[0014] Furthermore, in step 1, the steel billets are multiple in the same batch, and the lengths of the last sections of the bars corresponding to the multiple steel billets are measured; in step 2, the difference between the lengths of the last sections of the bars and the full-length bars is calculated, and the maximum and minimum values ​​of the multiple differences are determined; in step 3, the mass of the steel billet is increased to the mass of the steel billet corresponding to the minimum value of the multiple differences during the shearing stage. There are many factors that affect the length of the final rolled bar in the steelmaking and rolling process. For example, in the steelmaking process, the density of the steel billet changes continuously due to factors such as drawing speed and temperature; in addition, different steel billets may have length differences during the rolling process due to factors such as temperature, speed, and mechanical equipment status, which affects the quality consistency of the entire batch of products. By calculating the length difference of the last section of the bars corresponding to the multiple steel billets, and selecting the steel billet mass corresponding to the minimum difference for compensation, over-compensation caused by steel billets with excessive individual deviations can be avoided, excessive input of steel billets can be prevented, and the utilization rate of steel can be improved. In other words, selecting the minimum value among multiple differences for compensation can make the length of the bars in the entire production batch more uniform, reduce the situation where individual bars are too long or substandard due to over-compensation, improve the consistency of product quality, and achieve overall optimization of the production process, rather than just adjustments to a single billet.

[0015] Furthermore, in step 3, the length of the steel billet corresponding to the integer multiple of the full-length bar length is further increased during the steel billet shearing stage. By further increasing the length of the steel billet corresponding to the integer multiple of the full-length bar length, the difference in the length of the bars of different batches is increased, so that the bars of different batches are distinguished, and the length of each batch of bars produced is kept within a stable range.

[0016] Furthermore, in step 1, a counter is provided to record the number of flying shear shearing, and the number of flying shear shearing is used to determine the batch of the steel billet. The number of flying shear shearing of the steel billet is automatically recorded and used for batch determination, reducing the risk of errors that rely on manual recording and judgment.

[0017] Furthermore, in step 1, if the difference between the length of the last section of the bar and the length of the full-length bar is less than half of the length of the full-length bar, the number of full-length bars is recorded as the number of flying shear shearing plus 1; otherwise, the number of full-length bars is recorded as the number of flying shear shearing; the number of full-length bars is used to determine the batch of steel billets. By deciding whether to increase the number of full-length bars according to the difference between the length of the last section of the bar and the length of the full-length bar, the number of full-length bars actually produced can be more accurately reflected, the waste of resources caused by length deviation can be reduced, and more bars can be ensured to meet the full-length standard, thereby improving material utilization.

[0018] Furthermore, in step 1, if the difference between the length of the last section of the bar and the length of the full-length bar is greater than one-quarter of the full-length length and less than three-quarters of the full-length length, the corresponding billet will not be recorded in the same batch. The difference is within this range, which means that it is quite different from the expected and predicted steelmaking and rolling process. This may be caused by multiple factors, such as flying shear equipment errors, billet temperature fluctuations, uneven billet material composition, operator experience and reaction, production line speed changes, vibrations and mechanical interference. By excluding billets with length differences within a specific range from the same batch, it can be ensured that the length of the bars in each batch is more consistent, and after adjusting the billet length, the impact of length differences on the consistency of product quality can be reduced.

[0019] Furthermore, during the billet shearing stage, the target masses of the same batch of billets are equal. Equal target masses mean that the expected masses of the billets are equal. Generally speaking, the densities of billets with a small time interval are basically the same, and the target mass of the billets is set by setting the length of the billets. Using the same billet length for the same batch of billets can ensure that the physical properties and dimensions of these billets after rolling are as consistent as possible. In addition, it also simplifies the operation and control of the production process, and reduces errors or delays caused by frequent adjustments to the billet length. In this way, after changing the batch of billets, the billet length is adjusted, which improves the consistency of the bar length and the accuracy of the bar length regulation.

[0020] Beneficial effects of the present invention:

[0021] (1) The present invention can more effectively control the final length of the bar and reduce the length deviation by making adjustments during the steelmaking stage.

[0022] (2) The present invention reduces excessive reliance on the operating accuracy of the flying shear, thereby reducing the difficulty of operation.

[0023] (3) The present invention reduces the generation of waste and the necessity of subsequent trimming, reduces production costs, shortens the production cycle, and improves overall production efficiency.

[0024] Based on the above effects, the present invention has good application prospects in the field of metallurgical engineering technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention is a schematic diagram of a method for controlling the full multiple length of a bar in a steelmaking and rolling combined process.

[0026] Figure 2 It is a schematic diagram of the flying shear, cooling bed, rod, first length gauge, second length gauge and the last section of rod.

[0027] In the figure: 1. Flying shear; 2. Cooling bed; 3. Rod; 4. Last section of rod; 5. First length measuring instrument; 6. Second length measuring instrument. DETAILED DESCRIPTION

[0028] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and examples.

[0029] Example 1

[0030] The present invention provides a method for controlling the full multiple length of bars in a steelmaking and rolling combined process. Figure 1 As shown, it includes 3 steps. In order to clearly illustrate the present invention, the 3 steps are described as follows:

[0031] Step 1: Use the flying shear to cut the bars rolled from the billet and measure the length of the last section of the bar.

[0032] Figure 2 The flying shear 1 is used for shearing the bar material, the cooling bed 2 is used for placing and cooling the sheared bar material 3, the first length measuring instrument 5 and the second length measuring instrument 6 are suspended on the upper side of the cooling bed 2, and the first length measuring instrument 5 and the second length measuring instrument 6 are respectively located at the input end and the end of the cooling bed 2. The distance between the first length measuring instrument 5 and the second length measuring instrument 6 is a known fixed value. Figure 2The last section of the bar 4 is also shown. The first length measuring instrument 5 is used to measure the distance between the tail end of the last section of the bar 4 and the first length measuring instrument 5; the second length measuring instrument 6 is used to measure the distance between the beginning of the last section of the bar 4 and the second length measuring instrument 6. In this way, the length (abc) of the last section of the bar 4 can be calculated by the distance between the first length measuring instrument 5 and the second length measuring instrument 6 (assuming a), the distance between the tail end of the last section of the bar 4 and the first length measuring instrument 5 (assuming b), and the distance between the beginning of the last section of the bar 4 and the second length measuring instrument 6 (assuming c). In order to accurately measure the distance between the tail end or the beginning of the last section of the bar 4 and the first length measuring instrument 5 or the second length measuring instrument 6, the first length measuring instrument 5 and the second length measuring instrument 6 are selected as laser distance meters. The laser distance meter has high precision and fast response speed, and can accurately measure the above distance. In addition, the laser distance meter can be used in harsh industrial environments, has strong anti-interference ability, does not need to be in direct contact with strategic objects, and reduces wear and maintenance requirements. The first length measuring instrument 5 and the second length measuring instrument 6 are fixed on a solid and stable bracket to avoid vibration or offset affecting the measurement accuracy, ensure that the first length measuring instrument 5 and the second length measuring instrument 6 are perpendicular to the surface of the last section of the bar 4, and avoid errors caused by angle measurement. It should be noted that the present invention uses the first length measuring instrument 5 and the second length measuring instrument 6 to measure the length of the last section of the bar 4, which belongs to multi-point measurement. Single-point measurement is often limited by the position change of the measuring point. If the bar is displaced, tilted or the position is not fixed on the cooling bed, the result of the single-point measurement point is inaccurate. By measuring at both ends of the bar, the overall position of the bar can be better reflected. Even if the bar is slightly displaced, the actual length can be accurately calculated by the relative distance between the two measuring points. In addition, the bar often bends on the cooling bed. If only a single measuring point is used, the length measurement of the bent part will have a large deviation. By using two length measuring instruments to measure the two ends of the bar respectively, the influence of the bending can be averaged to ensure that the result is closer to the actual straight length of the bar.

[0033] Step 2: Calculate the difference between the length of the last section of the bar and the length of the full-length bar.

[0034] In step 2, the difference between the length of the last section of the bar and the length of the full-length bar is equal to the full-length bar length minus the length of the last section of the bar. Assuming that the length of the full-length bar is L and the length of the last section of the bar is abc, the above difference ΔL is L-(abc).

[0035] Step 3: According to the difference between the length of the last section of the bar and the length of the full-length bar, the length of the billet is changed during the billet shearing stage.

[0036] In step 3, the length of the increased billet is equal to the difference between the length of the last section of the bar and the length of the full-length bar multiplied by the mass of the unit length of the bar. Assuming that the mass of the unit length of the bar is m, the mass of the increased billet is [L-(abc)]m.

[0037] The present invention sets laser rangefinders at the input end and the end of the cooling bed respectively to accurately measure the length of the last section of the bar, and then calculates the difference between the length of the last section of the bar and the length of the full-length bar. According to the difference, the length of the billet is accurately changed during the billet shearing stage to ensure that the rolled bar meets the full-length standard. This method improves the accuracy of bar length control, reduces the scrap rate and material waste, and at the same time enhances the automation and efficiency of the production process, ensuring the consistency and quality stability of the product.

[0038] Example 2

[0039] On the basis of Example 1, in step 1, the steel billets are multiple in sequence from the same batch, and the lengths of the last sections of bars corresponding to the multiple steel billets are measured, wherein, in the stage of shearing the steel billets, the lengths of the steel billets in the same batch are equal; in step 2, the difference between the lengths of the multiple last sections of bars and the full-length bars is calculated, and the maximum and minimum values ​​of the multiple differences are determined; in step 3, in the stage of shearing the steel billets, the length of the steel billets is increased to the length of the steel billets corresponding to the minimum value of the multiple differences.

[0040] Specifically, the difference between the length of the last section of the bar and the full-length bar corresponding to each billet in the same batch of billets is ΔL i =L-(ab i -c i ), where i is the number of the billet. After calculating the length differences corresponding to multiple billets, find the maximum value ΔL in the difference max and minimum value ΔL min In the billet shearing stage, in order to ensure the consistency of the length of the same batch of billets, the increased billet length corresponds to the minimum difference ΔL min , that is, the increased mass of the billet is Δm=mΔL min , where m is the mass of the bar per unit length. Note that during the billet shearing stage, an equal billet mass Δm is added to the billets of the same batch to ensure that each billet can reach or approach the full length.

[0041] Preferably, in step 3, the length of the billet corresponding to an integer multiple of the full-length bar length is increased during the billet shearing stage. The mass of the full-length bar is mL, and the increased mass of the billet is nmL, where n is a non-zero integer.

[0042] Preferably, in step 1, a counter is further provided, and the counter is used to record the number of shearing times of the flying shear, and the number of shearing times of the flying shear is used to determine the batch of the steel billet. The counter is a photoelectric counter, and counts by detecting the photoelectric signal of the flying shear movement. The photoelectric counter has high precision and fast response speed, and can adapt to high-speed flying shear operation. Through the number of shearing times recorded by the counter, the system can automatically determine which batch each steel billet belongs to. For a steel billet, if the number of shearing times is the same, then these steel billets belong to one batch.

[0043] Preferably, in step 1, if the difference (ΔL) between the length of the last section of the bar and the length of the full-length bar is less than half of the length of the full-length bar (ΔL<(L / 2)), the number of full-length bars is recorded as the number of flying shear shearing plus 1, that is, the length of the last section of the bar is considered to be sufficient to be regarded as a complete full-length bar; otherwise, the number of full-length bars is recorded as the number of flying shear shearing, that is, the length of the last section of the bar is considered to be insufficient to be regarded as a complete full-length bar; the number of full-length bars is used to determine the batch of the billet. For a billet, if the number of full-length bars is the same, it is considered to be the same batch. Through this method, the number of full-length bars in production can be accurately managed to ensure that the length of the bars in each batch meets the requirements and improve the consistency of the product. This also reduces the error of judgment and improves the degree of automation of the production line.

[0044] Preferably, in step 1, if the difference between the length of the last section of the bar and the length of the full-length bar is greater than one-quarter of the full-length length and less than three-quarters of the full-length length, the corresponding steel billet is not recorded in the same batch. By excluding steel billets with a length difference between one-quarter and three-quarters of the full-length length from the same batch, significant differences in the length of bars within a batch are reduced, ensuring that the length of bars within each batch is more consistent, thereby improving the consistency of product quality.

[0045] In summary, the present invention provides a method for controlling the full-length length of bars in the combined process of steelmaking and steel rolling. The length of the bars is accurately measured by setting a laser rangefinder on the cooling bed, and the difference between the length of the bars and the full-length length is calculated based on the measurement result. The length of the billet is adjusted during the billet shearing stage according to the difference to ensure that the length of each bar reaches or approaches the full-length standard. At the same time, the number of flying shear shearings is recorded by a counter and combined with the difference judgment to achieve accurate division of batches and further optimize production management. This method improves the accuracy and efficiency of production, reduces material waste, ensures the consistency of product quality, and has good application prospects in the field of metallurgical engineering technology.

[0046] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A method for controlling the full multiple length of bars in a steelmaking and rolling process, characterized in that: The steps include: Step 1: Use a flying shear to cut the bars rolled from the billet and measure the length of the last section of the bars; Step 2, calculating the difference between the length of the last section of the bar and the length of the full-length bar; Step 3, changing the length of the billet during the billet shearing stage according to the difference between the length of the last section of the bar and the length of the full-length bar; Wherein, in step 1, the steel billets are multiple in sequence in the same batch, and the lengths of the last sections of bars corresponding to the multiple steel billets are measured; in step 2, the difference between the lengths of the multiple last sections of bars and the full-length bars is calculated, and the maximum and minimum values ​​of the multiple differences are determined; in step 3, the mass of the steel billet corresponding to the increased length of the steel billet in the steel billet shearing stage is the mass of the steel billet corresponding to the minimum value of the multiple differences; Wherein, in step 1, a counter is further provided, and the counter is used to record the number of flying shear shearing, and the number of flying shear shearing is used to determine the batch of the steel billet; in step 1, if the difference between the length of the last section of the bar and the length of the full-length bar is less than half of the length of the full-length bar, the number of full-length bars is recorded as the number of flying shear shearing plus 1; otherwise, the number of full-length bars is recorded as the number of flying shear shearing; the number of full-length bars is used to determine the batch of the steel billet.

2. The method for controlling the full multiple length of bars in the steelmaking and rolling process according to claim 1, characterized in that: In step 1, a first length measuring instrument and a second length measuring instrument are respectively arranged at the input end and the end of the cooling bed, and the length of the last section of the bar is calculated by the distance between the first length measuring instrument and the second length measuring instrument, the distance between the tail end of the last section of the bar and the first length measuring instrument, and the distance between the starting end of the last section of the bar and the second length measuring instrument.

3. The method for controlling the full multiple length of bars in the steelmaking and rolling process according to claim 1, characterized in that: In step 2, the difference between the length of the last section of the bar and the length of the full-length bar is equal to the length of the full-length bar minus the length of the last section of the bar.

4. The method for controlling the full multiple length of bars in the steelmaking and rolling process according to claim 1, characterized in that: In step 3, the mass of the steel billet corresponding to the increased length of the steel billet is equal to the difference between the length of the last section of the bar and the length of the full-length bar multiplied by the mass of the bar per unit length.

5. The method for controlling the full multiple length of bars in the steelmaking and rolling process according to claim 1, characterized in that: In step 3, during the billet shearing stage, the billet length corresponding to an integer multiple of the full-length bar length is increased.

6. The method for controlling the full multiple length of bars in the steelmaking and rolling process according to claim 5, characterized in that: During the billet shearing stage, the target quality of the billets in the same batch is equal.

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