Arrangement method of a tension leveller based on the combined light and heavy reduction technique

Abstract

The application provides a layout method of a withdrawing and straightening machine based on a light-heavy combined press-down technology, and belongs to the technical field of continuous casting. The method comprises the following steps: determining a press-down interval corresponding to each working condition speed of the light-heavy combined press-down technology; and ensuring that each working condition speed of the press-down interval is arranged with a preset minimum number of press-down rollers, and then the withdrawing and straightening machine is arranged. The application can solve the problem that in the prior art, there is no effective scheme for reducing the number of withdrawing and straightening machines under the premise of meeting the press-down process requirements.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of continuous casting, more particularly, to a layout method of a withdrawal-straightening machine based on a light-heavy combined press-down technology. BACKGROUND

[0002] The continuous casting solidification end press-down technology is an effective technical means for improving the core defects of a casting blank, and has been widely researched and applied in various blank types. In the past ten years or so, although the solidification end light press-down technology is still under continuous research and application, it has gradually developed into a heavy press-down (or large press-down) technology in order to obtain more optimal core quality of a casting blank and improvement of the final material performance.

[0003] At present, the understanding and application of the heavy press-down technology are not the same, but from the perspective of guiding theory and practical application, the heavy press-down technology can be roughly divided into three categories: (1) single-roller heavy press-down, which applies the heavy press-down as an independent technology; (2) increasing the total amount of press-down on the basis of light press-down; (3) light-heavy combined mode, which uses light press-down to improve segregation in front and uses heavy press-down to "weld" shrinkage holes to improve the density of a casting blank. However, no matter which implementation mode of heavy press-down is used, no design criteria for the layout of the press-down withdrawal-straightening machine are given.

[0004] The existing layout of the press-down withdrawal-straightening machine continues the design of the light press-down, and does not give an effective scheme that can be relied on from the mechanism and improvement effect. Generally, the following aspects are considered: from the process point of view, it is required that the roller spacing of the press-down withdrawal-straightening machine is as small as possible, for example, the roller spacing is 600-800 mm, which is considered to be beneficial to the continuous execution of press-down and the continuity of the action. However, no feasible design specification is given. From the equipment point of view, the strength of the withdrawal-straightening machine, the layout of the transmission, the size of the cylinder, hoisting, etc. are considered. Generally, the roller spacing is appropriately larger, for example, 0.95-1.6 m. In principle, the greater the required press-down force is, the larger the frame of the withdrawal-straightening machine is, and the larger the layout of the roller spacing is. The layout of the arc and straightening area needs a slightly larger roller spacing because the withdrawal space of the withdrawal-straightening machine needs to be considered. Therefore, the roller spacing is determined by the comprehensive consideration of the process and equipment, but the limit of the design from the guiding principle is not given, so as to achieve the reasonable integration of the process and equipment.

[0005] As described above, in the existing technology, the layout scheme of the withdrawal-straightening machine for the independent application of the light-heavy combined press-down is considered from the comprehensive roller spacing of the process and equipment, which is similar to a conventionally accepted fact, and the limit of the design from the guiding principle is not given. Therefore, for the layout of the withdrawal-straightening machine for the independent application of the light-heavy combined press-down, there is a lack of an effective scheme for reducing the number of withdrawal-straightening machines under the premise of meeting the press-down process requirements. SUMMARY

[0006] In view of the above problems, the purpose of the present application is to provide a layout method of a straightening and leveling mill based on a light-heavy combined reduction technology, so as to solve the problem that in the prior art, there is a lack of an effective solution to reduce the number of straightening and leveling mills under the premise of meeting the reduction process requirements for the layout of a straightening and leveling mill for light-heavy combined reduction.

[0007] The present application provides a layout method of a straightening and leveling mill based on a light-heavy combined reduction technology, comprising the following steps:

[0008] Determine the reducible interval corresponding to the drawing speed of each working condition of the light-heavy combined reduction technology; wherein the reducible interval is the interval from the start position of the reduction interval to the end position of the reducible interval;

[0009] Ensure that each working condition of the reducible interval is arranged with a preset minimum number of reduction rolls, and arrange the straightening and leveling mill.

[0010] In addition, the preferred solution is that the determination method of the start position of the reduction interval comprises:

[0011] According to the start position of the preset central solid phase rate standard interval, the start position of the reduction interval is obtained.

[0012] In addition, the preferred solution is that the determination method of the end position of the reducible interval comprises:

[0013] According to the end position of the preset central solid phase rate standard interval, the end position of the reduction interval is obtained;

[0014] According to the end position of the reduction interval and the preset adjustable reduction length, the end position of the reducible interval is determined.

[0015] In addition, the preferred solution is that the preset central solid phase rate standard interval is 0.3-1.0.

[0016] In addition, the preferred solution is that the determination of the end position of the reducible interval according to the end position of the reduction interval and the preset adjustable reduction length comprises:

[0017] The end position of the reducible interval is obtained by adding the end position of the reduction interval and the preset adjustable reduction length.

[0018] In addition, the preferred solution is that the preset adjustable reduction length is 0.3-1.0 m.

[0019] In addition, the preferred solution is that the arrangement of the straightening and leveling mill under the condition that each working condition of the reducible interval is arranged with a preset minimum number of reduction rolls comprises:

[0020] determine the length of the pressable interval corresponding to each working speed according to the start position and the end position of the pressable interval corresponding to each working speed of the light-heavy combination press-down technology;

[0021] determine the roll spacing of the pressable interval corresponding to each working speed according to the length of the pressable interval corresponding to each working speed and the preset minimum number of press-down rolls;

[0022] arrange the stretch-leveling machine based on the roll spacing of the pressable interval corresponding to each working speed.

[0023] In addition, preferably, after arranging the stretch-leveling machine, the method further comprises:

[0024] when the number of press-down rolls arranged in the pressable interval corresponding to the selected working speed is greater than the number of press-down rolls required to be executed in the press-down process during the execution of the light-heavy combination press-down process, the press-down process is executed by selecting the number of press-down rolls required to be executed in the press-down process from the side close to the end position of the pressable interval.

[0025] In addition, preferably, during the process of determining the pressable interval corresponding to each working speed of the light-heavy combination press-down technology,

[0026] determine the pressable interval corresponding to each working speed in turn according to the order of working speed from small to large; wherein the greater the working speed, the greater the corresponding pressable interval, and the greater the roll spacing of the stretch-leveling machine during arrangement.

[0027] In addition, preferably, the preset minimum number is 3-5.

[0028] As can be seen from the above technical solutions, the stretch-leveling machine arrangement method based on the light-heavy combination press-down technology provided by the present application first determines the pressable interval corresponding to each working speed of the light-heavy combination press-down technology, and then arranges the stretch-leveling machine under the condition that the pressable interval corresponding to each working speed is arranged with a preset minimum number of press-down rolls, so as to obtain the minimum arrangement of the stretch-leveling machine on the basis of meeting the process effect, effectively solve the problem that there is no maximum roll spacing design standard for the stretch-leveling machine in the prior art, and the limit design boundary that guarantees the press-down effect cannot be obtained, the present application avoids the fuzzy requirement for the equipment that the smaller the roll spacing, the better, achieves quantitative design, guarantees the press-down effect while using the minimum arrangement of the stretch-leveling machine, thereby effectively reducing the cost of the equipment under heavy pressure, and greatly reducing the comprehensive cost of production.

[0029] To the accomplishment of the foregoing and related ends, one or more aspects of the application, as generally described herein, include the features set forth in the following specification. The following description sets forth in specific detail certain illustrative aspects of the application. These aspects are indicative, however, of but a few of the various ways in which the principles of the application can be employed. Other aspects and advantages of the application will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating, by way of example, the principles of the application. BRIEF DESCRIPTION OF DRAWINGS

[0030] Other objects and advantages of the application will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating, by way of example, the principles of the application.

[0031] Figure 1 A flow chart of the arrangement method of the withdrawal and straightening machine based on the light-heavy combined press-down technology according to the embodiment of the application. DETAILED DESCRIPTION

[0032] In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. It can be evident, however, that the embodiments can be practiced without these specific details.

[0033] In view of the foregoing, there is a lack of an effective solution to reduce the number of withdrawal and straightening machines while meeting the press-down process requirements in the prior art. Therefore, an arrangement method of the withdrawal and straightening machine based on the light-heavy combined press-down technology is provided.

[0034] The specific embodiments of the application will be described below with reference to the accompanying drawings.

[0035] To illustrate the arrangement method of the withdrawal and straightening machine based on the light-heavy combined press-down technology provided by the application, Figure 1 A flow chart of the arrangement method of the withdrawal and straightening machine based on the light-heavy combined press-down technology according to the embodiment of the application is shown.

[0036] As Figure 1 shown, the arrangement method of the withdrawal and straightening machine based on the light-heavy combined press-down technology provided by the application includes the following steps:

[0037] Step S1, determining the press-down interval corresponding to the withdrawal speed of each working condition of the light-heavy combined press-down technology; wherein the press-down interval is the interval from the start position of the press-down interval to the end position of the press-down interval.

[0038] Specifically, in the press-down process of the light-heavy combined press-down technology, the steel grade of the casting blank and the withdrawal speed used are different under different working conditions. For the same steel grade, different withdrawal speeds will also result in different press-down intervals. Therefore, the press-down intervals corresponding to different withdrawal speeds under different working conditions need to be considered comprehensively. That is, the press-down intervals corresponding to different steel grades and different withdrawal speeds need to be considered comprehensively.

[0039] As a preferred scheme of the present application, the method for determining the start position of the pressing-down interval comprises:

[0040] The start position of the pressing-down interval is obtained according to the start position of the preset central solid phase rate standard interval.

[0041] Specifically, the start position of the pressing-down interval corresponding to the working drawing speed can be calculated by using the temperature model in the prior art according to the start value of the preset central solid phase rate standard interval and the working drawing speed. Since the temperature model is a common technique in the field, no further description is made. In the technical scheme of the present application, it is only necessary to understand that the start position of the pressing-down interval under each working drawing speed can be calculated by using the temperature model according to the given start value of the preset central solid phase rate standard interval.

[0042] As a preferred scheme of the present application, the method for determining the end position of the pressing-down interval comprises:

[0043] The end position of the pressing-down interval is obtained according to the end position of the preset central solid phase rate standard interval.

[0044] The end position of the pressing-down interval is obtained according to the end position of the pressing-down interval and the preset adjustable pressing-down length.

[0045] Specifically, the end position of the pressing-down interval corresponding to the working drawing speed can be calculated by using the temperature model in the prior art according to the end value of the preset central solid phase rate standard interval and the working drawing speed. Since the temperature model is a common technique in the field, no further description is made. In the technical scheme of the present application, it is only necessary to understand that the end position of the pressing-down interval under each working drawing speed can be calculated by using the temperature model according to the given end value of the preset central solid phase rate standard interval.

[0046] As a preferred scheme of the present application, the preset central solid phase rate standard interval is 0.3-1.0.

[0047] As a preferred scheme of the present application, the method for determining the end position of the pressing-down interval comprises:

[0048] The end position of the pressing-down interval is obtained according to the end position of the pressing-down interval and the preset adjustable pressing-down length.

[0049] As a preferred scheme of the present application, the preset adjustable pressing-down length is 0.3-1.0 m.

[0050] Specifically, the preset central solid phase rate standard interval and the preset adjustable pressing-down length are both obtained according to experimental verification, and are both given values in the technical scheme of the present application.

[0051] It should be noted that: in the technical solution of the present application, the method of determining the pressable interval corresponding to each working speed of the light-heavy combined press-down technology is not unique, and the pressable interval corresponding to different working speeds can also be determined through experience or experiments in actual operation, and there are many ways to determine the pressable interval corresponding to each working speed in the art, as long as the required pressable interval corresponding to each working speed in the technical solution can be obtained, and the present application does not make special limitation.

[0052] Step S2, ensure that each working speed corresponding to the pressable interval is arranged with a preset minimum number of press-down rollers, and the lay head is arranged.

[0053] Specifically, in the prior art, for the light-heavy combined press-down technology, the arrangement of the lay head is determined by the comprehensive consideration of process and equipment, but similar to the convention, the limit standard of the fusion of the two is not given, and it is generally believed that the smaller the roll spacing is, the better, and the equipment is required to be fuzzy. Based on this, the present application gives a scheme that can arrange the minimum lay head on the basis of ensuring the process requirements, that is, to ensure that each working speed corresponding to the pressable interval is arranged with a preset minimum number of press-down rollers, and the lay head is arranged.

[0054] As a preferred scheme of the present application, the condition of ensuring that each working speed corresponding to the pressable interval is arranged with a preset minimum number of press-down rollers includes:

[0055] According to the end position and the start position of the pressable interval corresponding to each working speed of the light-heavy combined press-down technology, the length of the pressable interval corresponding to each working speed is determined;

[0056] According to the length of the pressable interval corresponding to each working speed and the preset minimum number of press-down rollers, the press-down roller spacing of the pressable interval corresponding to each working speed is determined;

[0057] Based on the press-down roller spacing of the pressable interval corresponding to each working speed, the lay head is arranged.

[0058] Specifically, the length of the pressable interval corresponding to each working speed is calculated in turn, that is, the distance length from the end position to the start position of the pressable interval, and then the corresponding press-down roller spacing is determined according to the preset minimum number of press-down rollers, so that the lay head is arranged according to the press-down roller spacing.

[0059] As a preferred scheme of the present application, after the condition of ensuring that each working speed corresponding to the pressable interval is arranged with a preset minimum number of press-down rollers is arranged, it further includes:

[0060] In the execution of the light-heavy combined reduction process, when the number of reduction rolls arranged in the selected work condition reduction interval corresponding to the drawing speed is greater than the number of reduction rolls required to be executed in the reduction process, the reduction process is executed by selecting the number of reduction rolls required to be executed in the reduction process from the side close to the termination position of the reduction interval.

[0061] Specifically, in the execution of the reduction process, according to the "farthest principle", that is, when there are more than the minimum number of reduction rolls in the reduction interval corresponding to a specific drawing speed, the reduction process is executed by selecting the number of reduction rolls required to be executed in the reduction process from the side close to the termination position of the reduction interval.

[0062] As a preferred embodiment of the present application, in the process of determining the reduction interval corresponding to each work condition drawing speed of the light-heavy combined reduction technology,

[0063] The reduction interval corresponding to each work condition drawing speed is determined in turn according to the order of the work condition drawing speed from small to large; wherein the larger the work condition drawing speed, the larger the corresponding reduction interval, and the larger the reduction roll spacing when the drawing and straightening machine is arranged.

[0064] Specifically, from the solidification characteristics, as the work condition drawing speed increases, the reduction interval increases, so that the reduction roll spacing can be appropriately increased.

[0065] As a preferred embodiment of the present application, the preset minimum number is 3-5.

[0066] Specifically, the preset minimum number in the present application is 3-5, which is based on actual experimental verification.

[0067] By first determining the reduction interval corresponding to each work condition drawing speed of the light-heavy combined reduction technology, then ensuring that each work condition drawing speed corresponds to a reduction interval with a preset minimum number of reduction rolls arranged, the drawing and straightening machine is arranged, so as to obtain the minimum arrangement of the drawing and straightening machine while meeting the process effect, effectively solving the problem that there is no maximum design standard for the roll spacing of the drawing and straightening machine in the prior art, and the limit design boundary cannot be obtained to ensure the reduction effect. The present application avoids the vague requirement of the prior art that the smaller the roll spacing, the better, achieves quantitative design, ensures the reduction effect while using the minimum drawing and straightening machine, thereby effectively reducing the cost of the equipment used in the heavy reduction, and greatly reducing the comprehensive cost of production.

[0068] In order to better describe the drawing and straightening machine arrangement method based on the light-heavy combined reduction technology provided by the present application, the following examples are given:

[0069] Example 1

[0070] Taking a 165X165mm square billet caster of a certain steel plant as an example, the main steel grade produced by the caster is 82B, therefore, according to the solidification process of 82B steel, the layout of the withdrawal and straightening machine is arranged, the light and heavy combined press-down technology is used, the press-down interval standard is the center solid phase rate of 0.3-1.0, the adjustable press-down length is 0.6m, and according to this, the parameter data of the press-down interval corresponding to the withdrawal speed of each working condition is shown in Table 1.

[0071]

[0072] Table 1

[0073] According to the parameter data of the press-down interval corresponding to the withdrawal speed of each working condition in Table 1, the layout process of the withdrawal and straightening machine is as follows by using the layout method of the withdrawal and straightening machine provided by the present application.

[0074] The preset minimum number of press-down rolls is 5, according to the condition of limiting the number of press-down rolls in the press-down interval, first, according to the press-down interval of the minimum 2.2m / min withdrawal speed, the positions of 1#-5# press-down withdrawal and straightening machines are designed, which need to meet that there are 5 withdrawal and straightening machines within 13.0-16.8m, and the interval of the press-down rolls needs to be kept basically 0.9m; on this basis, the withdrawal speed is increased in sequence, and the rear withdrawal and straightening machines are arranged according to the condition of limiting the number of press-down rolls in the press-down interval. The final layout of the withdrawal and straightening machines meeting the condition of limiting the number of press-down rolls in the press-down interval under all working conditions is shown in Table 2. While meeting the withdrawal speeds of 2.5m / min and 2.6m / min, the interval of the press-down rolls can be appropriately increased with the increase of the working condition withdrawal speed, and the number of the withdrawal and straightening machines is reduced as much as possible. Among them, the withdrawal and straightening machine in the embodiment of the present application is a single-roller withdrawal and straightening machine, that is, a withdrawal and straightening machine with a pair of press-down rolls.

[0075] Roll number Tension leveler position (m) Roll gap (m) 1# 13.0 / 2# 13.9 0.9 3# 14.8 0.9 4# 15.7 0.9 5# 16.6 0.9 6# 17.5 0.9 7# 18.4 0.9 8# 19.4 1.0

[0076] Table 2

[0077] The layout of the withdrawal and straightening machine by using the layout method of the withdrawal and straightening machine provided by the present application is a scheme of using the least withdrawal and straightening machine on the basis of meeting the process effect, which is beneficial to reduce the cost of the equipment under heavy press-down, and greatly reduces the comprehensive cost of production.

[0078] On the basis of arranging the tension leveler provided by the tension leveler arrangement method, the roll gap can be reduced, similar to the smaller the better, but the equipment cost will be greatly increased. If the roll gap is reduced, there are obviously more tension levelers than the minimum number of tension levelers in the press-down interval under certain tension conditions, at which time the process can be performed according to the "farthest principle". That is, when the number of press-down rolls arranged in the press-down interval corresponding to the selected working tension is greater than the number of press-down rolls required to perform the press-down process during the execution of the light and heavy combined press-down process, the number of press-down rolls required to perform the press-down process is selected from the side close to the termination position of the press-down interval to perform the press-down process.

[0079] The embodiment of the present application only considers one main steel grade, and other steel grades also need to be considered in specific engineering design, so comprehensive treatment is still needed.

[0080] The tension leveler arrangement method provided by the present application mainly considers the process requirements, which is beneficial to simplify the equipment, and other conditions on the equipment also need to be considered for optimization, such as lifting, straightening, and blank dragging.

[0081] It should be noted that this embodiment is only for detailed description of the tension leveler arrangement method based on the light and heavy combined press-down technology provided by the present application in actual application, and does not limit the technical solutions provided by the present application.

[0082] As can be seen from the above specific embodiments, the tension leveler arrangement method based on the light and heavy combined press-down technology provided by the present application determines the press-down interval corresponding to each working tension of the light and heavy combined press-down technology first, and then ensures that each press-down interval corresponding to each working tension is arranged with a preset minimum number of press-down rolls, thereby arranging the tension leveler, so as to obtain the minimum arrangement of the tension leveler while meeting the process effect, effectively solve the problem that there is no maximum roll gap design standard in the prior art, and the limit design boundary cannot be obtained to ensure the press-down effect. The present application avoids the vague requirement of the prior art that the smaller the roll gap, the better, achieves quantitative design, ensures the press-down effect, uses the minimum tension leveler arrangement, and effectively reduces the cost of equipment used in heavy press-down, thereby greatly reducing the comprehensive cost of production.

[0083] The tension leveler arrangement method based on the light and heavy combined press-down technology according to the present application is described above with reference to the accompanying drawings in an exemplary manner. However, those skilled in the art should understand that various improvements can be made to the tension leveler arrangement method based on the light and heavy combined press-down technology provided by the present application without departing from the content of the present application. Therefore, the protection scope of the present application should be determined by the content of the appended claims.

Claims

1. A method of arranging a tension leveller based on a combined light-heavy reduction technique, characterized in that, The method comprises the following steps: Determine the corresponding press-down interval of each working speed of the light-heavy combination press-down technology; wherein, the press-down interval is the interval from the start position of the press-down interval to the end position of the press-down interval; Ensure that each working speed corresponding to the press-down interval is arranged with a preset minimum number of press-down rolls, and arrange the stretch-leveling machine.

2. The method of arranging a tension leveller based on the combined weight and reduction technology according to claim 1, characterized in that, The method for determining the start position of the press-down interval comprises: According to the start position of the preset central solid phase rate standard interval, the start position of the press-down interval is obtained.

3. The method of arranging a tension leveller based on the combined weight and reduction technology according to claim 1, characterized in that, The method for determining the end position of the press-down interval comprises: According to the end position of the preset central solid phase rate standard interval, the end position of the press-down interval is obtained; According to the end position of the press-down interval and the preset adjustable press-down length, the end position of the press-down interval is determined.

4. A method of arranging a skin pass mill based on the combined light-heavy reduction technique according to claim 2 or 3, characterized in that, The preset central solid phase rate standard interval is 0.3-1.

0.

5. The method of arranging a skin pass mill based on the combined weight and reduction technology according to claim 3, characterized in that, According to the end position of the press-down interval and the preset adjustable press-down length, the end position of the press-down interval is determined. The preset adjustable press-down length is 0.3-1.0 m.

6. A method of arranging a skin pass mill based on the combined light-heavy reduction technique according to claim 3 or 5, characterized in that, The method for arranging the stretch-leveling machine according to the condition that each working speed corresponding to the press-down interval is arranged with a preset minimum number of press-down rolls comprises:

7. The method of arranging a skin pass mill based on the combined weight and reduction technology according to claim 1, characterized in that, According to the end position and the start position of the press-down interval corresponding to each working speed of the light-heavy combination press-down technology, the length of the press-down interval corresponding to each working speed is determined; According to the length of the press-down interval corresponding to each working speed and the preset minimum number of press-down rolls, the press-down roll spacing of the press-down interval corresponding to each working speed is determined; Based on the press-down roll spacing of the press-down interval corresponding to each working speed, the stretch-leveling machine is arranged. After the stretch-leveling machine is arranged according to the condition that each working speed corresponding to the press-down interval is arranged with a preset minimum number of press-down rolls, the method further comprises:

8. The method of arranging a skin pass mill based on the combined light and heavy reduction technology according to claim 1, characterized in that, During the execution of the light-heavy combination press-down process, when the number of press-down rolls arranged in the press-down interval corresponding to the selected working speed is greater than the number of press-down rolls required for the press-down process, the number of press-down rolls required for the press-down process is selected from the side close to the end position of the press-down interval to execute the press-down process. During the determination of the press-down interval corresponding to each working speed of the light-heavy combination press-down technology, 9. The method of arranging a skin pass mill based on the combined light and heavy reduction technology according to claim 1, characterized in that, The press-down interval corresponding to each working speed is determined in turn according to the order of working speed from small to large; wherein, the greater the working speed, the greater the corresponding press-down interval, and the greater the press-down roll spacing when the stretch-leveling machine is arranged.

10. The stretch-leveling machine arrangement method based on the light-heavy combination press-down technology according to any one of claims 1, wherein The preset minimum number is 5. ​

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