Hole pattern design method for bar high-quality steel and common steel mixed production

Abstract

The invention discloses a pass design method for mixed production of bar high-quality steel and common steel, which relates to the technical field of bar rolling process, and comprises the following steps: designing the base circle radius of the high-quality steel pass based on national standard positive tolerance, designing the base circle radius of the common steel pass based on negative tolerance, and controlling the difference between the base circle radiuses of the high-quality steel pass and the base circle radius of the common steel pass to be 0.15-0.25 mm; high-quality steel and common steel hole patterns are integrated in different rolling grooves of the same roller, the maximum groove matching number is dynamically adjusted according to the specification, and the rolling grooves are distributed according to the yield proportion; by adjusting the expansion radius, the roll gap precision and the outer fillet radius, the dimensional precision of the high-quality steel is improved to more than two groups from three groups in the national standard. Under the framework of a low-cost two-roller mill, high-precision rolling of high-quality steel and negative difference maximization production of common steel are both considered, the method is suitable for a round steel mixing production line with the diameter being 20-45 mm, and the technical problem that in a traditional process, collaborative optimization of precision and the yield is difficult is solved.

Description

Technical Field

[0001] The invention relates to the technical field of bar rolling technology, and in particular to a pass design method for mixed production of high-quality steel and ordinary steel bars. Background Art

[0002] In the field of steel rolling technology, bar production lines are widely used to produce two types of products: ordinary carbon round steel (ordinary steel) and high-quality round steel (high-quality steel). In the existing technology, conventional two-roll mills use a single finished product hole system for production, and the same hole is used for both ordinary steel and high-quality steel rolling. However, this solution has significant defects: insufficient dimensional accuracy: when producing high-quality steel, it can only meet the minimum accuracy requirements of the national standard size (such as the national standard three-group accuracy), and cannot meet the high-precision needs of high-end customers; negative difference rolling is limited: when producing ordinary steel, because the hole design is not optimized for negative tolerances, the room for improving the yield rate is limited, and it is difficult to achieve rolling with maximum negative difference; high equipment cost: some high-end companies use three-roll or four-roll sizing units to improve accuracy, but the equipment investment and operation and maintenance costs are high, making it difficult to promote in small and medium-sized production lines.

[0003] In addition, the existing single-hole system lacks flexible configuration capabilities and cannot dynamically adjust rolling groove resources according to the production demand of high-quality steel and ordinary steel, resulting in low capacity utilization and inability to flexibly allocate according to the production ratio, further restricting production efficiency.

[0004] Therefore, how to achieve high-precision rolling of high-quality steel and maximize the negative difference of ordinary steel through hole design optimization under a low-cost two-roll mill architecture, and improve the dynamic allocation efficiency of rolling groove resources, has become a technical problem that needs to be solved urgently. Summary of the Invention

[0005] In response to the technical problems raised above, a pass design method for mixed production of high-quality and ordinary steel bars is provided. The present invention achieves high-precision rolling and improved yield rates through differentiated pass design, roll integration, and dynamic groove adjustment.

[0006] To achieve the above object, the present invention provides a pass design method for mixed production of high-quality steel and ordinary steel bars, comprising the following steps:

[0007] S1. For round steel with specifications from Φ20mm to Φ45mm, the pass profiles for high-quality steel and ordinary steel are designed respectively, where:

[0008] The base circle radius of the hole profile of high-quality steel products is designed based on the upper limit of the positive tolerance of the national standard, and the base circle radius of the hole profile of ordinary steel products is designed based on the lower limit of the negative tolerance of the national standard;

[0009] The difference in base circle radius between high-quality steel and ordinary steel is 0.15mm~0.25mm, and the difference in slot width is 0.1mm~0.3mm;

[0010] S2. Turning the high-quality steel finished pass profile and the ordinary steel finished pass profile into different rolling grooves of the same roll, and dynamically adjusting the maximum number of grooves of the roll according to the specifications;

[0011] S3. Based on the total output of a single batch and the amount of steel passed through a single groove, the number of grooves shall be allocated according to the output ratio of high-quality steel and ordinary steel, where:

[0012] For specifications of Φ20mm to Φ28mm, the maximum number of slots is 12 to 15;

[0013] For specifications of Φ30mm to Φ45mm, the maximum number of slots is 8 to 12;

[0014] S4. Based on the ovality and dimensional parameters of the finished product measured during the rolling process, the expansion radius, roll gap, and outer fillet radius of the high-quality steel pass profile and the ordinary steel pass profile are optimized and iteratively adjusted until the ovality of the high-quality steel is ≤0.3mm and the dimensional accuracy reaches the national standard group II or above.

[0015] Furthermore, in step S1, the expansion radius of the high-quality steel finished pass is set to 20 mm to 28 mm, and the expansion radius of the ordinary steel finished pass is set to 23 mm to 31 mm. The expansion angle of the high-quality steel and ordinary steel is set to 30° or 35° according to the specifications, and the difference in expansion angle between the high-quality steel and ordinary steel under the same specification does not exceed 5°.

[0016] Furthermore, the dynamic adjustment rule of the number of roller grooves is as follows:

[0017] For every 5mm increase in specification, the maximum number of grooves decreases by 1 to 2, among which Φ20mm corresponds to 15 grooves, and Φ45mm corresponds to 8 grooves, and the number of rolling grooves decreases in steps as the specification increases.

[0018] Furthermore, the groove quantity configuration rule in step S3 is:

[0019] Assume the total number of slots is N 总 , the planned output of ordinary steel accounts for P%, and the planned output of high-quality steel accounts for Y%, satisfying P%+Y%=100%;

[0020] Number of slots for ordinary steel = round(N 总 × P%);

[0021] Number of holes and slots in high-quality steel = N 总 -Number of slots for ordinary steel.

[0022] Furthermore, the base circle radius difference in step S1 is dynamically adjusted according to the specifications:

[0023] The difference in base circle radius between Φ20mm high-quality steel and ordinary steel is 0.15mm, and the difference in Φ45mm specification is 0.25mm, and the difference value increases linearly with the increase of specification.

[0024] Furthermore, the roller processing in step S2 is carried out in stages, the initial hole parameters are set based on theoretical calculations, the expansion radius is reversely corrected and the outer fillet radius is optimized according to the actual rolling size data, and the correction range does not exceed 5% of the original parameter value.

[0025] Furthermore, the method covers a range of round steel specifications from Φ20 mm to Φ45 mm, and the hole parameters of high-quality steel and ordinary steel are stored and called separately through independent process procedures.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] 1. The present invention provides a hole design method for the mixed production of high-quality steel and ordinary steel bars. Through differentiated finished product hole design, the dimensional accuracy of the high-quality steel finished products is improved from the national standard group 3 to the national standard group 2, and some specifications can reach the national standard group 1 accuracy, meeting the needs of high-end customers for high-precision round steel.

[0028] 2. The present invention provides a hole design method for the mixed production of high-quality steel and ordinary steel bars. The ordinary steel finished product hole is designed based on negative tolerance, which maximizes the negative difference rolling, improves the comprehensive yield rate of ordinary steel, and significantly saves raw material costs in single batch production.

[0029] 3. The present invention provides a hole design method for the mixed production of high-quality steel and ordinary steel bars, which dynamically allocates the number of rolling grooves on the same rolling roll according to the production ratio of high-quality steel and ordinary steel, reduces the number of roll changes, improves roll utilization and production efficiency, and reduces equipment operation and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0031] Figure 1 This is a flow chart of a pass design method for mixed production of high-quality steel and ordinary steel bars in an embodiment of the present invention;

[0032] Figure 2 Schematic diagram of a pass pattern for ordinary steel in a method for designing a pass pattern for mixed production of high-quality steel and ordinary steel in a bar according to an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of a pass profile for the superior steel in a method for designing a pass profile for mixed production of superior steel and ordinary steel bars according to an embodiment of the present invention. DETAILED DESCRIPTION

[0034] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0035] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described 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, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0036] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0037] Unless otherwise specifically stated, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​described in these embodiments do not limit the scope of the present invention. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The techniques, methods and equipment known to ordinary technicians in the relevant fields may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, so once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0038] In the description of the present invention, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention: the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0039] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below their position devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0040] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0041] Example 1

[0042] like Figures 1 to 3 As shown, the present invention provides a pass design method for mixed production of high-quality steel and ordinary steel bars, comprising the following steps:

[0043] S1. For round steel with specifications from Φ20mm to Φ45mm, including Φ20mm, Φ22mm, Φ25mm, Φ28mm, Φ30mm, Φ32mm, Φ35mm, Φ36mm, Φ38mm, Φ40mm, Φ42mm, and Φ45mm, the pass profiles for high-quality steel products and ordinary steel products are designed respectively, among which:

[0044] As shown in Table 1, the base circle radius of the hole profile of high-quality steel products is designed based on the upper limit of the positive tolerance of the national standard, and the base circle radius of the hole profile of ordinary steel products is designed based on the lower limit of the negative tolerance of the national standard;

[0045] The difference of base circle radius between the high-quality steel and the common steel is 0.15mm-0.25mm, and the difference of notch width is 0.1mm-0.3mm, for example, the difference of Φ20mm is 0.15mm, the difference of Φ45mm is 0.25mm, and the difference increases linearly with the increase of the size;

[0046] S2, the high-quality steel finished hole type and the common steel finished hole type are turned to different rolling grooves of the same branch roller, and the maximum number of grooves of the roller is dynamically adjusted with the size, wherein the maximum number of grooves decreases by 1-2 with the increase of 5mm of the size, wherein Φ20mm corresponds to 15 grooves, Φ45mm corresponds to 8 grooves, and the number of grooves decreases in steps with the increase of the size;

[0047] S3, according to the total output of single batch and the amount of steel passing through single groove, the number of grooves is allocated according to the yield ratio of high-quality steel and common steel, wherein:

[0048] For Φ20mm-Φ28mm size, the maximum number of grooves is 12-15;

[0049] For Φ30mm-Φ45mm size, the maximum number of grooves is 8-12;

[0050] Let the total number of holes and grooves be N 总 , N 总 According to table 2, the planned yield of common steel accounts for P%, and the yield of high-quality steel accounts for Y%, and P%+Y%=100% is satisfied;

[0051] Then the number of common steel holes and grooves is round(N 总 ×P%);

[0052] The number of high-quality steel holes and grooves is N 总 -the number of common steel holes and grooves.

[0053] S4, the size of finished material is measured in real time, and the expansion radius, roll gap and outer corner radius of high-quality steel hole type and common steel hole type are iteratively adjusted based on the measured ovality and size parameters in the rolling process, until the ovality of high-quality steel is less than or equal to 0.3mm and the size precision reaches the second group of national standard or above;

[0054] The correction of expansion radius: according to the measured size, the correction is made in reverse, and the correction range is less than or equal to 5% of the original parameter value;

[0055] Roll gap adjustment: the roll gap of common steel of the same size is equal to the roll gap of high-quality steel;

[0056] Outer corner radius adjustment: according to the difference of base circle radius, combined with the actual production situation, the outer corner radius of high-quality steel of different sizes is reduced or increased by 0.1-0.5mm or equal to that of common steel.

[0057] Furthermore, in step S1, the expansion radius of the high-quality steel finished pass is set to 20 mm to 28 mm, and the expansion radius of the ordinary steel finished pass is set to 23 mm to 31 mm. The expansion angle of the high-quality steel and ordinary steel is set to 30° or 35° according to the specifications, and the difference in expansion angle between the high-quality steel and ordinary steel under the same specification does not exceed 5°.

[0058] Furthermore, the base circle radius difference in step S1 is dynamically adjusted according to the specifications:

[0059] The difference in base circle radius between Φ20mm high-quality steel and ordinary steel is 0.15mm, and the difference in Φ45mm specification is 0.25mm, and the difference value increases linearly with the increase of specification.

[0060] Furthermore, the roller processing in step S2 is carried out in stages, the initial hole parameters are set based on theoretical calculations, the expansion radius is reversely corrected and the outer fillet radius is optimized according to the actual rolling size data, and the correction range does not exceed 5% of the original parameter value.

[0061] Furthermore, the method covers a range of round steel specifications from Φ20 mm to Φ45 mm, and the hole parameters of high-quality steel and ordinary steel are stored and called separately through independent process procedures.

[0062] Example 2

[0063] Based on the method of Example 1, the specification of this embodiment is Φ22mm;

[0064] S1, Independent design of the finished pass profiles of high-quality steel and ordinary steel

[0065] Base circle radius design: ordinary steel base circle radius: 10.90mm (national standard negative tolerance lower limit), high-quality steel base circle radius: 11.05mm (national standard positive tolerance upper limit), base circle radius difference: 0.15mm;

[0066] Notch width difference: ordinary steel notch width: 22.6mm, high-quality steel notch width: 22.8mm, notch width difference: 0.2mm;

[0067] Expansion angle: 30° for both ordinary steel and high-quality steel;

[0068] Expansion radius: 26.2mm for ordinary steel, 23mm for high-quality steel;

[0069] Roll gap: The roll gap for ordinary steel and high-quality steel is 3.0mm;

[0070] Outer fillet radius: 0.3mm for ordinary steel, 0.6mm for high-quality steel.

[0071] S2 and S3, mixed processing of rollers and dynamic adjustment of groove matching

[0072] Φ22mm high-quality steel and ordinary steel pass shapes are turned into different grooves on the same roll. According to Table 2, the maximum number of grooves is determined to be 15. In the example, the planned output of ordinary steel accounts for 55% and the proportion of high-quality steel accounts for 45%. Therefore, the number of grooves for ordinary steel is 8 and the number of grooves for high-quality steel is 7.

[0073] S4. Parameter optimization and adjustment

[0074] In the initial parameters, the expansion radius of ordinary steel is 26.2mm, the expansion radius of high-quality steel is 23mm, and the measured ovality of high-quality steel is 0.35mm, which exceeds the target value by 0.3mm.

[0075] Modify the parameters:

[0076] The expansion radius of ordinary steel is 25mm, and the correction range is -1.2mm, ≤5% of the original value;

[0077] Excellent steel expansion radius is 22mm, correction range: -1.0mm, ≤5% of original value;

[0078] Roll gap adjustment: The roll gap for ordinary steel and high-quality steel is 3.0mm;

[0079] Optimization of outer corners: The outer corner radius of high-quality steel is reduced to 0.3mm, while that of ordinary steel remains at 0.3mm.

[0080] After optimization, the ovality of the high-quality steel is reduced to 0.25mm, and the dimensional accuracy reaches the national standard group II.

[0081] The optimized Φ22mm parameters are archived as "Excellent Circle 22" and "Puyuan 22" respectively.

[0082] Example 3

[0083] Based on the method of Example 1, the specification of this embodiment is Φ28mm;

[0084] S1, Independent design of the finished pass profiles of high-quality steel and ordinary steel

[0085] Base circle radius design: ordinary steel base circle radius: 13.90mm (national standard negative tolerance lower limit), high-quality steel base circle radius: 14.15mm (national standard positive tolerance upper limit), base circle radius difference: 0.25mm;

[0086] Notch width difference: ordinary steel notch width: 28.6mm, high-quality steel notch width: 29.13mm, notch width difference: 0.53mm;

[0087] Expansion angle: 35° for ordinary steel and 30° for high-quality steel, with a difference of 5°;

[0088] Expansion radius: ordinary steel 21.27mm, high-quality steel 26mm;

[0089] Roll gap: 4.0mm for common steel, 3.5mm for high quality steel;

[0090] Outside corner radius: 1.5mm for common steel, 1.0mm for high quality steel.

[0091] S2 and S3, mixed processing of rollers and dynamic adjustment of grooves

[0092] Φ28mm high quality steel pass and common steel pass are turned to different grooves of the same roller, the maximum number of grooves is 12 according to Table 2, the common steel planned yield accounts for 50%, and the high quality steel accounts for 50%, so the number of common steel grooves is 6, and the number of high quality steel grooves is 6;

[0093] S4, parameter optimization and adjustment

[0094] In the initial parameters, the common steel expansion radius is 21.27mm, the high quality steel expansion radius is 26mm, the measured value of common steel ellipticity is 0.40mm, and the measured value of high quality steel ellipticity is 0.28mm;

[0095] Correct the parameters:

[0096] Common steel expansion radius: 20mm, correction range: -1.27mm, ≤5% of the original value;

[0097] High quality steel expansion radius: 25mm, correction range: -1.0mm, ≤5% of the original value;

[0098] Roll gap adjustment: the roll gap of common steel and high quality steel is 3.5mm;

[0099] Outside corner optimization: the outside corner radius of high quality steel is reduced to 0.8mm, and the common steel remains 1.5mm. After optimization, the high quality steel ellipticity is reduced to 0.25mm, and the size accuracy reaches the national standard two groups. The optimized Φ28mm parameters are respectively archived as "high round 28" and "common round 28".

[0100] Table 1 optimized pass parameters

[0101]

[0102] Table 2 maximum number of grooves of the roller

[0103]

[0104] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions described in the foregoing examples can be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A pass design method for mixed production of high-quality steel and ordinary steel bars, characterized in that: The following steps are involved: S1. For round steel with specifications from Φ20mm to Φ45mm, the pass profiles for high-quality steel and ordinary steel are designed respectively, where: The base circle radius of the hole profile of high-quality steel products is designed based on the upper limit of the positive tolerance of the national standard, and the base circle radius of the hole profile of ordinary steel products is designed based on the lower limit of the negative tolerance of the national standard; The difference in base circle radius between high-quality steel and ordinary steel is 0.15mm~0.25mm, and the difference in slot width is 0.1mm~0.3mm; S2. Turning the high-quality steel finished pass profile and the ordinary steel finished pass profile into different rolling grooves of the same roll, and dynamically adjusting the maximum number of grooves of the roll according to the specifications; S3. Based on the total output of a single batch and the amount of steel passed through a single groove, the number of grooves shall be allocated according to the output ratio of high-quality steel and ordinary steel, where: For specifications of Φ20mm to Φ28mm, the maximum number of slots is 12 to 15; For specifications of Φ30mm to Φ45mm, the maximum number of slots is 8 to 12; S4. Based on the ovality and dimensional parameters of the finished product measured during the rolling process, the expansion radius, roll gap, and outer fillet radius of the high-quality steel pass profile and the ordinary steel pass profile are optimized and iteratively adjusted until the ovality of the high-quality steel is ≤0.3mm and the dimensional accuracy reaches the national standard group II or above.

2. The hole design method for mixed production of high-quality steel and ordinary steel bars according to claim 1 is characterized in that: In step S1, the expansion radius of the high-quality steel finished pass is set to 20 mm to 28 mm, and the expansion radius of the ordinary steel finished pass is set to 23 mm to 31 mm. The expansion angles of the high-quality steel and ordinary steel are set to 30° or 35° according to the specifications, and the difference in expansion angles between the high-quality steel and ordinary steel of the same specification does not exceed 5°.

3. The hole design method for mixed production of high-quality steel and ordinary steel bars according to claim 1 is characterized in that: The dynamic adjustment rule of the number of roller grooves is: For every 5mm increase in specification, the maximum number of grooves decreases by 1 to 2, among which Φ20mm corresponds to 15 grooves, and Φ45mm corresponds to 8 grooves, and the number of rolling grooves decreases in steps as the specification increases.

4. The hole design method for mixed production of high-quality steel and ordinary steel bars according to claim 1, characterized in that: The rule for configuring the number of grooves in step S3 is: Assume the total number of slots is N 总 , the planned output of ordinary steel accounts for P%, and the planned output of high-quality steel accounts for Y%, satisfying P%+Y%=100%; Number of slots for ordinary steel = round(N 总 × P%); Number of holes and slots in high-quality steel = N 总 -Number of slots for ordinary steel.

5. The hole design method for mixed production of high-quality steel and ordinary steel bars according to claim 1, characterized in that: In step S1, the base circle radius difference is dynamically adjusted according to the specifications: The difference in base circle radius between Φ20mm high-quality steel and ordinary steel is 0.15mm, and the difference in base circle radius between Φ45mm high-quality steel and ordinary steel is 0.25mm, and the difference value increases linearly with the increase of specification.

6. The hole design method for mixed production of high-quality steel and ordinary steel bars according to claim 1, characterized in that: The roller processing in step S2 is carried out in stages. The initial hole parameters are set based on theoretical calculations. The expansion radius is reversely corrected and the outer corner radius is optimized according to the actual rolling size data. The correction range does not exceed 5% of the original parameter value.

7. The hole design method for mixed production of high-quality steel and ordinary steel bars according to claim 1, characterized in that: The round steel specifications covered by the method include Φ20mm to Φ45mm, and the hole parameters of high-quality steel and ordinary steel are stored and called respectively through independent process procedures.

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