A high-speed bar single-pass production line

Abstract

The present invention provides a high-speed bar production line with a single pass profile, comprising a roughing mill, an intermediate mill, a pre-finishing mill, a first finishing mill, and a second finishing mill. The intermediate mill adopts a double-slitting system for its pass profile. The pre-finishing mill comprises a first-line pre-finishing mill and a second-line pre-finishing mill. The first finishing mill comprises a first-line finishing mill and a second-line finishing mill. The second finishing mill comprises a third-line finishing mill and a fourth-line finishing mill. The mills located at the ends of the intermediate mill in the rolling direction have a pass profile corresponding to a base circle diameter of 28.0 to 28.5 mm. The third-line finishing mill and the fourth-line finishing mill each comprise two finishing mills, and each finishing mill in the second finishing mill is independently driven by a motor. The production line of the present invention can significantly reduce the number of spare rolls, roller rings, and supporting guides required for the production line, thereby reducing workload, lowering labor intensity, improving production efficiency, and lowering production costs.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical steel rolling high-speed bar and threaded steel production, in particular to a high-speed bar single-pass production line. Background Art

[0002] High-speed bar production line is mainly used for small-size rebar for construction The production of finished products has a rolling speed of more than 40m / s, with the characteristics of high output, low cost, high dimensional accuracy, and high yield rate. The conventional typical high-speed bar production line layout is as follows Figure 1 As shown, the production line mainly includes roughing mill group 01, intermediate rolling mill group 02, pre-finishing rolling mill group 03, finishing rolling mill group 04, double-length flying shear 05, high-speed steel feeding device 06, cooling bed area equipment 07 and collection area equipment 08.

[0003] Among them, the roughing mill group 01 includes six rolling mills, arranged in a horizontal and vertical alternating manner (horizontal means that the roller axis of the rolling mill is placed horizontally, and vertical means that the roller axis of the rolling mill is placed vertically), and are driven by individual motors; the intermediate rolling mill group 02 includes six rolling mills, arranged in a horizontal and vertical alternating manner, and are driven by individual motors; the pre-finishing mill group 03 includes six rolling mills, arranged in a horizontal-vertical-horizontal ... The second-line finishing mill group 042; the first-line finishing mill group 041 and the second-line finishing mill group 042 both include six rolling mills, which are arranged crosswise at 45° (the roller ring axes of the rolling mills are inclined 45° and crosswise), and each of the six rolling mills is centrally driven by one motor; the finished rolled products are rolled out after the finishing mill group 04; the finished rolled products then pass through the double-length flying shear 05 and the high-speed steel feeding device 06, and enter the cooling bed area equipment 07 and the collection area equipment 08 to cool and collect the finished rolled products.

[0004] The hole system arrangement corresponding to this production line layout is shown in Table 1 below. It can be divided into basic hole patterns and adjusted hole patterns. The basic hole pattern refers to the hole pattern when the base circle is a perfect circle. It is the hole pattern obtained after turning the rollers or roller rings (generally, roughing mill group 01 and intermediate rolling mill group 02 use rollers, and pre-finishing mill group 03 and finishing mill group 04 use roller rings). The adjusted hole pattern is based on the basic hole pattern and is obtained by adjusting the roll gap (raising or slightly lowering the roll gap). Its base circle is no longer a perfect circle. When producing rebar, the hole patterns of the finished product pre-hole and the finished product hole corresponding to the rolling of rebar of different specifications must use their respective basic hole patterns, and the corresponding rolling mills must replace the roller rings.

[0005] Table 1: Hole system arrangement table in the prior art

[0006]

[0007] Among them, the solid black pattern in Table 1 (for example ) represents the basic hole type, solid hollow pattern (e.g. ) represents the hole type adjustment, Represents emptiness.

[0008] use Figure 1 The production line is arranged according to the hole system in Table 1. When producing threaded steel products, the specific process is as follows:

[0009] Production Taking the rebar of specifications as an example, it is first rolled by the roughing mill group 01 and the intermediate rolling mill group 02: the hole type of the rolling mill in the 1st to 2nd passes adopts the box type system, and the cross-section of the rolled piece is rolled into a flat box shape and a square box shape in turn; the hole type of the rolling mill in the 3rd to 12th passes adopts the elliptical-circular system, and the cross-section of the rolled piece is alternately rolled into an elliptical shape and a circular shape in turn, and the more passes, the smaller the cross-section size of the rolled piece. After the 6th pass, the cross-section of the rolled piece is a circle with a diameter of 78 mm, after the 8th pass, the cross-section of the rolled piece is a circle with a diameter of 63 mm, after the 10th pass, the cross-section of the rolled piece is a circle with a diameter of 53 mm, and after the 12th pass, the cross-section of the rolled piece is a circle with a diameter of 42 mm.

[0010] Then it is rolled through the pre-finishing mill group 03: the pass type of the 13th to 18th passes adopts a double-cutting system, and the cross-section of the rolled piece is rolled into a flat square, a flat square, a dumbbell shape, two parallel connected circles, two separate ovals and two separate circles. After the 18th pass, the rolled piece is cut into two circular sections with a diameter of 18.5mm. Next, it enters the first-line finishing mill group 041 and the second-line finishing mill group 042 respectively. The pass type of each pass adopts an elliptical-circular system. The cross-sectional size of the rolled piece gradually decreases and the accuracy gradually increases. Finally, after the 24th pass, the specification is obtained. Finished rolled products.

[0011] Production For example, the rebar of the specification is first rolled through the roughing mill group 01 and the intermediate rolling mill group 02: the 1st to 10th rolling mills are connected to the production The hole size is the same as the specification. After the 10th pass, the cross-section of the rolled piece is a circle with a diameter of 53mm; the 11th to 12th passes of the rolling mill adopt an empty pass (the corresponding rollers are replaced with empty rollers). Then it is rolled through the pre-finishing mill group 03: the hole shape of the rolling mill for the 13th to 18th passes adopts a cutting system. After the 18th pass, the rolled piece is cut into two circular sections with a diameter of 23mm. Next, it enters the first-line finishing mill group 041 and the second-line finishing mill group 042 respectively. The hole shape of each pass adopts the elliptical-circular system. Finally, after the 24th pass, the specification is obtained. Finished rolled products.

[0012] The hole types used in the production of various specifications of threaded steel are detailed in Table 1 above. It can be seen that the hole type system is used to produce When producing products, the roughing mill group 01 and the intermediate rolling mill group 02 (1st to 12th passes) have only one basic hole type, that is, a single hole type (the single hole type mentioned here is for each rolling mill. When producing products of all specifications, if the rolls of the rolling mill do not need to be replaced with new rolls, only the roll gap needs to be adjusted or the rolls need to be passed through, then the production pass of the rolling mill can be called single hole type rolling. For the rolling mill that needs to replace the rolls with new rolls when producing products of different specifications, the production pass of the rolling mill is not a single hole type). No matter which specification of the product is produced, it only needs to be passed through (the corresponding rolls or roll rings are replaced with pass rollers or pass tubes) or the size of the roll gap is adjusted. There is no need to replace the rolls of the rolling mill with new rolls of other specifications. Specifically: production When producing rebar of different specifications, all 1 to 12 rolling mills adopt basic pass type; When producing rebar of different specifications, the 1st to 10th passes of the rolling mill adopt the basic pass type, and the 11th and 12th passes of the rolling mill adopt the empty pass type; Specifications: the 1st to 8th passes of the rolling mill adopt the basic pass type, and the 9th to 12th passes of the rolling mill adopt the empty pass type.

[0013] However, since the six rolling mills in the first-line finishing mill group 041 and the six rolling mills in the second-line finishing mill group 042 are driven centrally by one motor, the extension coefficient of each rolling mill is fixed and cannot be adjusted when the centralized drive is used. Therefore, when the rolled products are cut by the pre-finishing mill group 03 and enter the finishing mill group 04, the cross-sectional dimensions of the rolled products required for producing rebars of different specifications are different. For example, when producing and When producing rebar of different specifications, the cross-sections of the rolled products need to be circular with diameters of 18.5mm, 23mm, and 27.5mm, respectively. The cross-sectional dimensions vary greatly, and the finishing mill 04 has high requirements for dimensional accuracy. It is impossible to obtain the required hole shape by adjusting the roll gap, so the roller rings need to be replaced when producing products of different specifications. At the same time, because the pre-finishing mill 03 uses a double-slit system, the final circular cross-sections with diameters of 18.5mm, 23mm, and 27.5mm are required, that is, three cross-sections of different sizes. According to the requirements of their respective elongation coefficients, when entering the pre-finishing mill 03 after passing through the intermediate rolling mill 02, the corresponding circular cross-sections are required to have diameters of 42mm, 53mm, and 63mm, that is, three cross-sections with significantly different sizes. Therefore, the roller rings of each rolling mill in this double-slit system also need to be replaced when producing products of different specifications.

[0014] Therefore, for the high-speed bar production line of the prior art, its pre-finishing mill group 03 and finishing mill group 04 need to be equipped with multiple sets of basic pass types. When the conventional specifications are changed, the roller rings need to be replaced with roller rings of the corresponding pass types. For example, when the production specifications are changed from Replace with When rolling, it is necessary to replace all the roller rings of the corresponding rolling mill with roller rings of the corresponding hole type in 10 passes from 13th to 22nd pass before production can begin; the switching of other specifications is similar. However, when adjusting the roll gap, it is not necessary to replace the rolls or roll rings, only the roll gap needs to be raised or slightly lowered; when emptying, it is only necessary to remove the original rolls or roll rings and the guides of the rolling mill, and then replace them with empty rollers or empty tubes. There is no need to install the guides, and no adjustment is required when installing the empty rollers or empty tubes, which is simple and convenient; when replacing the rolls or roll rings with new rolls or roll rings, it is necessary to first remove the original rolls or roll rings and the guides of the rolling mill, and then install the new rolls or roll rings and the new guides, and readjustment is required when installing the new rolls or roll rings. Replacing once not only takes a long time to change and adjust the rolls, but also has a large workload and high labor intensity, which reduces the operating efficiency of the production line; at the same time, the more basic hole systems there are, the more spare rolls, roll rings and matching guides are needed for the production line, which greatly increases the inventory cost of the production line.

[0015] Therefore, the inventors, relying on their many years of experience and practice in related industries, have proposed a high-speed bar single-pass production line to overcome the defects of the prior art. Summary of the Invention

[0016] The purpose of the present invention is to provide a high-speed bar single-pass production line, which can greatly reduce the number of spare rollers, roller rings and matching guides on the production line, reduce workload, reduce labor intensity, improve the production efficiency of the production line and reduce production costs.

[0017] The object of the present invention is achieved in this way: a high-speed bar single-pass production line includes a roughing mill group, an intermediate rolling mill group, a pre-finishing mill group, a first finishing mill group and a second finishing mill group arranged in sequence along the rolling direction; the pass of the intermediate rolling mill group adopts a double-slitting system, the pre-finishing mill group includes a first-line pre-finishing mill group and a second-line pre-finishing mill group arranged in parallel, the first finishing mill group includes a first-line finishing mill group and a second-line finishing mill group arranged in parallel, and the second finishing mill group includes a third-line finishing mill group and a fourth-line finishing mill group arranged in parallel. ; The first-line pre-finishing mill group, the first-line finishing mill group and the third-line finishing mill group are connected in series in sequence to form the first branch rolling line, and the second-line pre-finishing mill group, the second-line finishing mill group and the fourth-line finishing mill group are connected in series in sequence to form the second branch rolling line; the rolling mill located at the end of the rolling direction in the intermediate rolling mill group adopts a circular hole type and the corresponding base circle diameter is 28.0~28.5mm; the third-line finishing mill group and the fourth-line finishing mill group each include two finishing mills, and each finishing mill in the second finishing mill group is driven by a separate motor.

[0018] In a preferred embodiment of the present invention, the first-line pre-finishing mill group and the second-line pre-finishing mill group each include four pre-finishing mills, and the hole profiles of the first to fourth pre-finishing mills of each of them alternately use elliptical hole profiles and circular hole profiles; the first-line finishing mill group and the second-line finishing mill group each include four finishing mills, and the hole profiles of the first to fourth finishing mills of each of them alternately use elliptical hole profiles and circular hole profiles.

[0019] In a preferred embodiment of the present invention, the base circle diameter corresponding to the hole profile of the rolling mill located at the end of the rolling direction in the intermediate rolling mill group is 28.2 mm; the hole profile height of the second pre-finishing mill in the first-line pre-finishing mill group and the second-line pre-finishing mill group is 23 mm or 24.3 mm, and the hole profile height of the fourth pre-finishing mill in the first-line pre-finishing mill group and the second-line pre-finishing mill group is 18 mm or 19 mm; the base circle diameter corresponding to the hole profile of the second finishing mill in the first-line finishing mill group and the second-line finishing mill group is 15 mm, and the base circle diameter corresponding to the hole profile of the fourth finishing mill in the first-line finishing mill group and the second-line finishing mill group is 12 mm.

[0020] In a preferred embodiment of the present invention, each pre-finishing mill in the first-line pre-finishing mill group and the second-line pre-finishing mill group is arranged alternately in horizontal and vertical directions, and each pre-finishing mill is driven by a separate motor; each finishing mill in the first-line finishing mill group, the second-line finishing mill group, the third-line finishing mill group and the fourth-line finishing mill group is arranged crosswise at 45°.

[0021] In a preferred embodiment of the present invention, the first and second finishing mills in the first and second finishing mill groups are driven simultaneously by one motor, and the third and fourth finishing mills are driven simultaneously by one motor.

[0022] In a preferred embodiment of the present invention, the cross-sectional size of the raw material is 150mm×150mm, the roughing mill group includes six roughing mills, and adopts an extended hole system; the intermediate rolling mill group includes six intermediate rolling mills, the rolls of the first intermediate rolling mill are flat rolls, and the hole types of the second to sixth intermediate rolling mills are vertical roll edge hole type, pre-cut hole type, cutting hole type, cutting elliptical hole type and cutting circular hole type respectively. The sixth intermediate rolling mill is the rolling mill located at the end of the rolling direction in the intermediate rolling mill group.

[0023] In a preferred embodiment of the present invention, the extended hole system is a box-type system, a diamond-square system, a combination of a box-type system and an ellipse-circle system, or a combination of a diamond-square system and an ellipse-circle system.

[0024] In a preferred embodiment of the present invention, each roughing mill in the roughing mill group is arranged alternately in horizontal and vertical order, and each roughing mill is driven by a separate motor; each intermediate rolling mill in the intermediate rolling mill group is arranged in horizontal-vertical-horizontal-horizontal-horizontal-horizontal order, and each intermediate rolling mill is driven by a separate motor.

[0025] In a preferred embodiment of the present invention, a high-speed steel feeding device, cooling bed area equipment and collection area equipment are sequentially arranged along the rolling direction after the second finishing mill group.

[0026] In a preferred embodiment of the present invention, a flying shear is respectively provided between the roughing mill group and the intermediate rolling mill group, between the intermediate rolling mill group and the first line pre-finishing mill group and the second line pre-finishing mill group, between the first line pre-finishing mill group and the first line finishing mill group, between the first line finishing mill group and the third line finishing mill group, between the second line pre-finishing mill group and the second line finishing mill group, and between the second line finishing mill group and the fourth line finishing mill group; a flying shear and a double-length flying shear are sequentially provided along the rolling direction between the third line finishing mill group and the fourth line finishing mill group and the high-speed steel feeding device.

[0027] In a preferred embodiment of the present invention, cooling water tanks are respectively provided between the intermediate rolling mill group and the first line pre-finishing rolling mill group and the second line pre-finishing rolling mill group and after the corresponding flying shears; cooling water tanks are respectively provided between the first line pre-finishing rolling mill group and the first line finishing rolling mill group, between the first line finishing rolling mill group and the third line finishing rolling mill group, between the second line pre-finishing rolling mill group and the second line finishing rolling mill group, between the second line finishing rolling mill group and the fourth line finishing rolling mill group, between the third line finishing rolling mill group and the fourth line finishing rolling mill group and the high-speed steel feeding device and before the corresponding flying shears.

[0028] As described above, the production line of the present invention adopts a double-cutting system for the hole profile of the intermediate rolling mill group, and the rolled piece is cut into two identical circular cross-section rolled pieces after passing through the intermediate rolling mill group, and the diameters of the two rolled pieces obtained are controlled at 28.0~28.5mm; since the circular cross-section rolled pieces finally obtained after rolling by the roughing mill group and the intermediate rolling mill group have the same size when producing products of all specifications, the rolls of each rolling mill in the roughing mill group and the intermediate rolling mill group do not need to be replaced when producing products of all specifications, and each rolling mill rolls a single hole profile.

[0029] At the same time, the present invention cuts the rolled piece after the intermediate rolling mill, and the cross-sectional diameter of the rolled piece after cutting is 28.0-28.5 mm, which can cover The maximum dimensions of each specification of threaded steel in the required processing passes; and in the present invention, the hole profiles of the two finishing mills in each of the third line finishing mill group and the fourth line finishing mill group are respectively used as the pre-finished product hole and the finished product hole, and the mills corresponding to the pre-finished product hole and the finished product hole of all specifications of threaded steel are arranged in the last two stands of all rolling mills, and these two finishing mills are driven by a separate motor, which can facilitate the adjustment of the elongation coefficient when the specifications are changed; in this way, when producing products of all specifications, there is no need to replace the roller rings for the pre-finishing mill group and the first finishing mill group, and each rolling mill is rolled with a single hole profile. In addition, the rolling mills corresponding to the pre-finished product hole and the finished product hole of all specifications of threaded steel are arranged in the last two stands of all rolling mills, and can also enter water cooling immediately after the finished rolled piece is obtained, which helps to improve the organizational properties of the finished rolled piece.

[0030] With this arrangement, each mill in the roughing, intermediate, pre-finishing, and first finishing mills can achieve single-pass rolling. When switching between different specifications on the line, only the roller rings of the last two mills need to be replaced; the remaining mills remain unchanged, idle, or only require roll gap adjustment. Compared to the typical high-speed bar production line layout in the prior art, the production line of the present invention can achieve single-pass rolling for all specifications of rebar production, offering greater flexibility and adaptability. This reduces the time and difficulty of manual roll changes when changing specifications, from approximately 20 to 80 minutes to approximately 10 minutes, significantly improving production efficiency. Furthermore, single-pass rolling significantly reduces the inventory of rolls, roller rings, and guides, lowering production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The following drawings are only intended to illustrate and explain the present invention, and are not intended to limit the scope of the present invention.

[0032] in:

[0033] Figure 1 : It is a schematic diagram of the planar layout of a high-speed bar production line in the prior art.

[0034] Figure 2 : Schematic diagram of the planar layout of the high-speed bar single-hole production line provided by the present invention.

[0035] Figure 3 :for Figure 2 A partial enlarged view of point A in the middle.

[0036] Figure 4 :for Figure 2 A partial enlarged view of point B in the middle.

[0037] Description of Figure Numbers:

[0038] Existing technology:

[0039] 01. Roughing mill; 02. Intermediate rolling mill; 03. Pre-finishing mill; 04. Finishing mill; 041. First-line finishing mill; 042. Second-line finishing mill; 05. Double-length flying shear; 06. High-speed steel feeding device; 07. Cooling bed area equipment; 08. Collection area equipment.

[0040] The present invention:

[0041] 1. Roughing mill; 2. Intermediate rolling mill; 3. Pre-finishing mill; 31. First line pre-finishing mill; 32. Second line pre-finishing mill; 4. First finishing mill; 41. First line finishing mill; 42. Second line finishing mill; 5. Second line finishing mill; 51. Third line finishing mill; 52. Fourth line finishing mill;

[0042] 6. Cooling water tank; 71. Flying shear; 72. Multiple-length flying shear; 8. High-speed steel feeding device; 9. Cooling bed area equipment; 10. Collection area equipment. DETAILED DESCRIPTION

[0043] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described with reference to the accompanying drawings.

[0044] like Figures 2 to 4 As shown, this embodiment provides a high-speed bar single-pass production line, including a roughing mill group 1, an intermediate rolling mill group 2, a pre-finishing mill group 3, a first finishing mill group 4 and a second finishing mill group 5 arranged in sequence along the rolling direction.

[0045] The intermediate mill group 2 utilizes a dual-slit pass system. The pre-finishing mill group 3 comprises a first pre-finishing mill group 31 and a second pre-finishing mill group 32, arranged in parallel. The first finishing mill group 4 comprises a first finishing mill group 41 and a second finishing mill group 42, arranged in parallel. The second finishing mill group 5 comprises a third finishing mill group 51 and a fourth finishing mill group 52, arranged in parallel. The first pre-finishing mill group 31, the first finishing mill group 41, and the third finishing mill group 51 are connected in series to form the first branch mill line. The second pre-finishing mill group 32, the second finishing mill group 42, and the fourth finishing mill group 52 are connected in series to form the second branch mill line. The mill at the end of the intermediate mill group 2 in the rolling direction uses a circular pass with a base circle diameter of 28.0 to 28.5 mm. The third finishing mill group 51 and the fourth finishing mill group 52 each include two finishing mills, and each finishing mill in the second finishing mill group 5 is driven by a separate motor.

[0046] In the production line of this embodiment, the pass profile of the intermediate rolling mill group 2 adopts a double-slitting system. After passing through the intermediate rolling mill group 2, the rolled piece is cut into two identical circular cross-section rolled pieces, and the diameters of the two rolled pieces obtained are controlled at 28.0-28.5 mm. Since the circular cross-section rolled pieces finally obtained after rolling by the roughing rolling mill group 1 and the intermediate rolling mill group 2 are of the same size when producing products of all specifications, the rolls of each rolling mill in the roughing rolling mill group 1 and the intermediate rolling mill group 2 do not need to be replaced when producing products of all specifications, and each rolling mill performs rolling with a single pass profile.

[0047] At the same time, in this embodiment, the rolled piece is cut after the intermediate rolling mill group 2, and the cross-sectional diameter of the rolled piece after cutting is 28.0-28.5 mm, which can cover The maximum size of each specification of rebar in the required processing passes; and in this embodiment, the hole profiles of the two finishing mills in the third line finishing mill group 51 and the fourth line finishing mill group 52 are respectively used as the pre-finished product hole and the finished product hole, and the mills corresponding to the pre-finished product hole and the finished product hole of all specifications of rebar are arranged in the last two stands of all rolling mills, and these two finishing mills are driven by a separate motor, which can facilitate the adjustment of the elongation coefficient when changing specifications; in this way, when producing products of all specifications, there is no need to replace the roller rings for the pre-finishing mill group 3 and the first finishing mill group 4, and each rolling mill is rolled with a single hole profile. In addition, the rolling mills corresponding to the pre-finished product hole and the finished product hole of all specifications of rebar are arranged in the last two stands of all rolling mills, and can also enter water cooling immediately after the finished rolled piece is obtained, which helps to improve the structural properties of the finished rolled piece.

[0048] With this arrangement, each of the rolling mills in roughing mill group 1, intermediate mill group 2, pre-finishing mill group 3, and first finishing mill group 4 can achieve single-pass rolling. When switching between different specifications on the line, only the roll rings of the last two rolling mills need to be replaced; the remaining rolling mills remain unchanged, idle, or only require roll gap adjustment. Compared with the layout of a typical high-speed bar production line in the prior art, the production line in this embodiment can achieve single-pass rolling for all specifications of rebar production, offering greater flexibility and adaptability. This reduces the time and difficulty of manual roll changes during specification changes, from approximately 20 to 80 minutes to approximately 10 minutes, significantly improving production efficiency. Furthermore, single-pass rolling significantly reduces the inventory of rolls, roll rings, and guides, lowering production costs.

[0049] In a specific implementation, to minimize the number of rolling mills and basic pass profiles while meeting the rolling requirements of various rebar specifications, the first pre-finishing mill group 31 and the second pre-finishing mill group 32 each include four pre-finishing mills, and the pass profiles of the first through fourth pre-finishing mills in each line alternate between elliptical and circular pass profiles. The first finishing mill group 41 and the second finishing mill group 42 each include four finishing mills, and the pass profiles of the first through fourth finishing mills in each line alternate between elliptical and circular pass profiles.

[0050] Thus, the two parallel single-line rolling mills, namely, the first pre-finishing mill group 31 and the first finishing mill group 41, and the second pre-finishing mill group 32 and the second finishing mill group 42, each have eight rolling mills, which is the minimum number of rolling mills required to meet rolling requirements. With this number of rolling mills, after rolling through the roughing mill group 1 and the intermediate mill group 2 to produce a round cross-section rolled product with a diameter of 28.0 to 28.5 mm, the corresponding pass system arrangement for the pre-finishing mill group 3 and the first finishing mill group 4 in this embodiment is shown in Table 2 below:

[0051] In detail, in production When the rebar of specifications is rolled, when the rolled product enters the pre-finishing mill group 3 and the first finishing mill group 4, the eight rolling mills in the two parallel single lines all adopt the basic pass type;

[0052] In production When the rebar of specifications is rolled, when the rolled pieces enter the pre-finishing mill group 3 and the first finishing mill group 4, the first six rolling mills in the two parallel single lines adopt the basic pass type, and the last two rolling mills adopt the empty pass type;

[0053] In production When the rolled steel bar enters the pre-finishing mill group 3 and the first finishing mill group 4, the first four rolling mills in the two parallel single lines adopt the basic pass type, and the last four rolling mills adopt the empty pass type.

[0054] In production When the rolled steel bar enters the pre-finishing mill group 3 and the first finishing mill group 4, the first two rolling mills in the two parallel single lines adopt the basic pass type, the middle two rolling mills adjust the roll gap based on the basic pass type, and the last four rolling mills adopt idle pass;

[0055] In production When the rebar of specifications is rolled, when the rolled pieces enter the pre-finishing mill group 3 and the first finishing mill group 4, the first two rolling mills in the two parallel single lines adopt the basic pass type, and the last six rolling mills adopt the empty pass type;

[0056] In production When the rolled products enter the pre-finishing mill group 3 and the first finishing mill group 4, the first two rolling mills in the two parallel single lines adjust the roll gap based on the basic pass profile, and the last six rolling mills adopt idle pass;

[0057] In production When the rebar of the specification is rolled, when the rolled pieces enter the pre-finishing mill group 3 and the first finishing mill group 4, the eight rolling mills in the two parallel single lines all use empty passing.

[0058] Table 2: Hole system arrangement table in this embodiment

[0059]

[0060] Among them, the solid black pattern in Table 2 (for example ) represents the basic hole type, solid hollow pattern (e.g. ) represents the hole type adjustment, Represents emptiness.

[0061] In practice, to achieve finished products with optimal structural properties, the base diameter of the mill at the end of the rolling direction in the intermediate mill group 2 is 28.2 mm. The pass height of the second pre-finishing mill in each of the first and second pre-finishing mill groups 31 and 32 is 23 mm or 24.3 mm, and the pass height of the fourth pre-finishing mill in each of the first and second pre-finishing mill groups 31 and 32 is 18 mm or 19 mm. The pass height of the second finishing mill in each of the first and second finishing mill groups 41 and 42 is 15 mm, and the pass height of the fourth finishing mill in each of the first and second finishing mill groups 41 and 42 is 12 mm.

[0062] Specifically, the average elongation coefficient from the rolling mill at the end of the rolling direction in the intermediate rolling mill group 2 to the second pre-finishing mill is 1.226 or 1.16. When the average elongation coefficient is 1.226, the hole height of the second pre-finishing mill is 23 mm, which is the basic hole shape and is the production The pass profile of the second pre-finishing mill is corresponding to the rebar of the specification; when the average elongation coefficient is 1.16, the pass profile height of the second pre-finishing mill is 24.3mm. At this time, the adjusted pass profile is obtained by adjusting the roll gap based on the basic pass profile, which is the production The specification of rebar is the corresponding hole type of the second pre-finishing mill.

[0063] The average elongation coefficient of the second to fourth pre-finishing mills is 1.278 or 1.21. When the average elongation coefficient is 1.278, the hole height of the fourth pre-finishing mill is 18mm, which is the basic hole shape. The pass profile of the fourth pre-finishing mill is corresponding to the rebar of the specification; when the average elongation coefficient is 1.21, the pass profile height of the fourth pre-finishing mill is 19mm. At this time, the adjusted pass profile is obtained by adjusting the roll gap based on the basic pass profile, which is the production The specification of rebar is the hole type corresponding to the fourth pre-finishing mill.

[0064] The average elongation coefficient from the fourth pre-finishing mill to the second finishing mill in the first finishing mill group 4 is 1.2, corresponding to a pass height of 15 mm for the second finishing mill in the first finishing mill group 4, which is a basic pass.

[0065] The average elongation coefficient of the second to fourth finishing mills in the first finishing mill group 4 is 1.25, corresponding to a pass height of 12 mm for the fourth finishing mill in the first finishing mill group 4, which is a basic pass.

[0066] The above average elongation coefficient or pass height can be used to produce finished products of corresponding specifications, and the microstructure and properties of the finished products obtained at this size are optimized. Of course, if the base circle diameter corresponding to the pass of the rolling mill located at the end of the rolling direction in the intermediate rolling mill group 2 is selected to a different value, the average elongation coefficient or pass height of each pass in the pre-finishing rolling mill group 3 and the first finishing rolling mill group 4 will be adaptively adjusted to optimize the microstructure and properties of the finished products.

[0067] In practice, due to the large size, distance, and low operating speed of the individual mills in the pre-finishing mill group 3, the pre-finishing mills in the first and second pre-finishing mill groups 31 and 32 are arranged in a horizontal and vertical alternating configuration for ease of layout, with each pre-finishing mill independently driven by a separate motor. This compact arrangement of mills within each finishing mill group improves product precision. The finishing mills in the first, second, third, and fourth finishing mill groups 41, 42, 51, and 52 are arranged at a 45° angle to each other, lowering the equipment's center of gravity and ensuring stability during high-speed operation. This also facilitates roller ring replacement and mill equipment maintenance.

[0068] Furthermore, the first and second finishing mills in the first and second finishing mill groups 41 and 42 are driven simultaneously by one motor, and the third and fourth finishing mills in the first and second finishing mill groups 41 and 42 are driven simultaneously by one motor.

[0069] Due to production When producing rebar of specifications, the four finishing mills of the two single lines in the first finishing mill group 4 all need basic pass profiles; When producing rebar of a specified specification, only the first two of the four finishing mills on the two single lines of the first finishing mill group 4 require a basic pass profile; the remaining two can be idle. Therefore, the first and second finishing mills in the first finishing mill group 4 are driven by a single motor, while the third and fourth finishing mills are driven by a single motor. When the third and fourth finishing mills are idle, the corresponding motors can be shut down to save energy and reduce consumption. This one-to-two drive system makes it easier to control the operating conditions of each mill and saves costs.

[0070] Furthermore, in this embodiment, the cross-sectional size of the raw material is 150mm×150mm, and the roughing mill group 1 includes six roughing mills, which adopt an extended hole system. The intermediate rolling mill group 2 includes six intermediate rolling mills, the rolls of the first intermediate rolling mill are flat rolls, and the hole types of the second to sixth intermediate rolling mills are vertical roll edge hole type, pre-slitting hole type, slitting hole type, slitting elliptical hole type and slitting circular hole type, respectively. The sixth intermediate rolling mill is the mill located at the end of the rolling direction in the intermediate rolling mill group 2. For these twelve rolling mills in the roughing mill group 1 and the intermediate rolling mill group 2, the 150mm×150mm billet is obtained. The average elongation coefficient of the rolled piece is 1.27.

[0071] The aforementioned extended pass system can be a box-type system, a diamond-square system, a combination of a box-type system and an elliptical-circular system, or a combination of a diamond-square system and an elliptical-circular system. During use, the corresponding extended pass system can be selected according to actual needs. For example, in this embodiment, as shown in Table 2, the pass profiles of the first and second roughing mills adopt the box-type system, while the pass profiles of the third through sixth roughing mills adopt the elliptical-circular system (i.e., elliptical and circular pass profiles are alternately used).

[0072] Of course, in actual production, other types of extension pass systems can be used as needed; this embodiment is merely an example. Furthermore, the cross-sectional dimensions of the raw material can be selected as needed, and the number of individual rolling mills in the roughing mill group 1 and the intermediate mill group 2 can be increased or decreased accordingly, with the corresponding average extension coefficients adjusted accordingly. For example, as the cross-sectional dimensions of the raw material increase, in order to rationally distribute the extension coefficients, additional rolling mills can be added before, during, or after the roughing mill group 1, or before the intermediate mill group 2 (the pass of these additional rolling mills still using the extension pass system).

[0073] In the specific implementation, due to the large size and distance between the rolling mills in roughing mill group 1 and intermediate mill group 2, the roughing mills in roughing mill group 1 are arranged alternately in a horizontal and vertical arrangement for ease of placement, and each roughing mill is driven by a separate motor. In intermediate mill group 2, due to the requirements of the slitting pass system, the intermediate mills are arranged in a horizontal-vertical-horizontal-horizontal-horizontal-horizontal arrangement, and each intermediate mill is driven by a separate motor.

[0074] In a specific embodiment, when the roughing mill group 1 includes six roughing mills, the intermediate rolling mill group 2 includes six intermediate rolling mills, the first-line pre-finishing mill group 31 and the second-line pre-finishing mill group 32 each include four pre-finishing mills, the first-line finishing mill group 41 and the second-line finishing mill group 42 each include four finishing mills, the third-line finishing mill group 51 and the fourth-line finishing mill group 52 each include two finishing mills; when the base circle diameter corresponding to the pass of the rolling mill located at the end of the rolling direction in the intermediate rolling mill group 2 is 28.2 mm, the pass system arrangement corresponding to the production line is as shown in Table 2 above.

[0075] In detail, the entire production line has a total of 32 rolling mills, which are divided into 22 passes. Generally, each rolling is counted as one pass. In this embodiment, each rolling mill in the roughing mill group 1 and the intermediate rolling mill group 2 is counted as one pass. Starting from the pre-finishing mill group 3, it is divided into a parallel first branch rolling line and a second branch rolling line. A certain rolled piece can only go through one of the branch rolling lines, and each rolling in the branch rolling line undergoes one pass. Therefore, a rolled piece goes through 22 passes from entering the roughing mill group 1 to the end of rolling in the second finishing mill group 5.

[0076] 1st to 12th pass rolling mill: The pass adopts the extended pass system and double cutting system, and the cross section of the billet with a cross section of 150mm×150mm is obtained. The average elongation coefficient of the rolled piece is 1.27.

[0077] 13th to 14th pass rolling mill: The pass adopts the elliptical-circular system, with the cross section The cross section is and The average elongation coefficients of the rolled product sizes are 1.226 and 1.16 respectively.

[0078] 15th to 16th pass rolling mill: The pass adopts the elliptical-circular system, with the cross section The cross section is 2 and The average elongation coefficients of the rolled product sizes are 1.278 and 1.21 respectively.

[0079] 17th to 18th pass rolling mill: The pass adopts the ellipse-circle system, with the cross section The cross section is The average elongation coefficient of the rolled piece is 1.2.

[0080] 19th to 20th pass rolling mill: The pass adopts the ellipse-circle system, with the cross section The cross section is The average elongation coefficient of the rolled product is 1.25.

[0081] 21st to 22nd pass rolling mill: The pass adopts the ellipse-circle system, The average elongation coefficient of the finished product is 1.188~1.286.

[0082] In production When rolling rebar of different specifications, the 1st to 20th rolling mills all use the basic pass type;

[0083] In production When rolling rebar of different specifications, the 1st to 18th passes of the rolling mill adopt the basic pass type, and the 19th and 20th passes of the rolling mill adopt the empty pass type;

[0084] In production When rolling rebar of different specifications, the 1st to 16th passes of the rolling mill adopt the basic pass type, and the 17th to 20th passes of the rolling mill adopt the empty pass type;

[0085] In production When rolling rebar of different specifications, the 1st to 14th passes adopt the basic pass type, the 15th and 16th passes adjust the roll gap based on the basic pass type, and the 17th to 20th passes adopt the empty pass;

[0086] In production When rolling rebar of different specifications, the 1st to 14th passes of the rolling mill adopt the basic pass type, and the 15th to 20th passes of the rolling mill adopt the empty pass type;

[0087] In production When rolling rebar of different specifications, the 1st to 12th passes adopt the basic pass type, the 13th and 14th passes adjust the roll gap based on the basic pass type, and the 15th to 20th passes adopt the empty pass type.

[0088] In production When rolling rebar of different specifications, the 1st to 12th passes of the rolling mill adopt the basic pass type, and the 13th to 20th passes of the rolling mill adopt the empty pass type;

[0089] all All specifications are rolled out as finished products in the 21st to 22nd rolling mill.

[0090] It can also be seen from this that in production When producing rebar products of different specifications, finished products are rolled out in the second finishing mill group 5 (21st to 22nd passes). For the roughing mill group 1, intermediate mill group 2, pre-finishing mill group 3, and first finishing mill group 4 (1st to 20th passes), there is only one basic pass profile, i.e., a single pass profile. Therefore, in this embodiment, the mills corresponding to the 1st to 20th passes all roll with a single pass profile. Regardless of the product specifications produced, only the roller rings of the 21st to 22nd passes need to be replaced. For the 1st to 20th passes, the rolls or roller rings of the mill do not need to be replaced. Only the roll gap size needs to be adjusted or the mill needs to be idled, and the same basic pass profile can be shared. This not only reduces roll changing time and improves production efficiency, but also significantly reduces the inventory of rolls, roller rings, and guides, greatly reducing costs.

[0091] Furthermore, in order to facilitate the cooling of the rolled pieces and the collection of the finished products, a high-speed steel feeding device 8, cooling bed area equipment 9 and collection area equipment 10 are sequentially arranged along the rolling direction after the second finishing mill group 5.

[0092] In actual application, a flying shear 71 is respectively installed between the roughing mill group 1 and the intermediate rolling mill group 2, between the intermediate rolling mill group 2 and the first line pre-finishing rolling mill group 31 and the second line pre-finishing rolling mill group 32, between the first line pre-finishing rolling mill group 31 and the first line finishing rolling mill group 41, between the first line finishing rolling mill group 41 and the third line finishing rolling mill group 51, between the second line pre-finishing rolling mill group 32 and the second line finishing rolling mill group 42, and between the second line finishing rolling mill group 42 and the fourth line finishing rolling mill group 52 for cutting the heads, tails, and lengths of the rolled products. A flying shear 71 and a multi-length flying shear 72 are respectively installed along the rolling direction between the third line finishing mill group 51 and the fourth line finishing mill group 52 and the high-speed steel feeding device 8. One flying shear 71 is used for cutting the rolled products, and the multi-length flying shear 72 is used for cutting the rolled products to multi-lengths.

[0093] Furthermore, to facilitate cooling of the rolled product and ensure that its deformation meets the requirements, cooling water tanks 6 are installed between the intermediate rolling mill group 2 and the first and second pre-finishing mill groups 31 and 32, and after the corresponding flying shears 71. Cooling water tanks 6 are also installed between the first pre-finishing mill group 31 and the first finishing mill group 41, between the first finishing mill group 41 and the third finishing mill group 51, between the second pre-finishing mill group 32 and the second finishing mill group 42, between the second finishing mill group 42 and the fourth finishing mill group 52, and between the third and fourth finishing mill groups 51 and 52 and the high-speed steel feeding device 8, and before the corresponding flying shears 71. During production, the rolled product passes through the cooling water in the cooling water tanks 6 to cool it.

[0094] The above description is only an illustrative embodiment of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principle of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A high-speed bar single-pass production line for producing The threaded steel bar is characterized in that It includes a roughing mill group, an intermediate rolling mill group, a pre-finishing mill group, a first finishing mill group and a second finishing mill group arranged in sequence along the rolling direction; The pass type of the intermediate rolling mill adopts a double-slit system. The pre-finishing mill group includes a first-line pre-finishing mill group and a second-line pre-finishing mill group arranged in parallel. The first finishing mill group includes a first-line finishing mill group and a second-line finishing mill group arranged in parallel. The second finishing mill group includes a third-line finishing mill group and a fourth-line finishing mill group arranged in parallel. The first-line pre-finishing mill group, the first-line finishing mill group and the third-line finishing mill group are sequentially connected in series to form a first branch rolling line. The second-line pre-finishing mill group, the second-line finishing mill group and the fourth-line finishing mill group are sequentially connected in series to form a second branch rolling line. The rolling mill located at the end of the intermediate rolling mill group in the rolling direction adopts a circular pass profile and the corresponding base circle diameter is 28.0-28.5 mm; the first line finishing mill group and the second line finishing mill group each include four finishing mills, and the pass profiles of the first to fourth finishing mills of each line alternately adopt elliptical pass profiles and circular pass profiles; the first and second finishing mills of each line finishing mill group are driven simultaneously by a motor, and the third and fourth finishing mills of each line finishing mill group are driven simultaneously by a motor; the third line finishing mill group and the fourth line finishing mill group each include two finishing mills, and each finishing mill of the second finishing mill group is driven separately by a motor; The single pass type is for each rolling mill. When producing products of all specifications, if the rolls of the rolling mill do not need to be replaced with new rolls, it is only necessary to adjust the roll gap or pass it through. After the second finishing mill group, a high-speed steel feeding device, cooling bed area equipment and collection area equipment are sequentially arranged along the rolling direction.

2. The high-speed bar single-pass production line according to claim 1, characterized in that: The first line pre-finishing mill group and the second line pre-finishing mill group each include four pre-finishing mills, and the pass profiles of the first to fourth pre-finishing mills of each of them alternately use elliptical pass profiles and circular pass profiles.

3. The high-speed bar single-pass production line according to claim 2, characterized in that: The base circle diameter of the rolling mill at the end of the rolling direction in the intermediate rolling mill group is 28.2 mm. The pass height of the second pre-finishing mill in each of the first and second pre-finishing mill groups is 23 mm or 24.3 mm, and the pass height of the fourth pre-finishing mill in each of the first and second pre-finishing mill groups is 18 mm or 19 mm; The base circle diameter corresponding to the pass profile of the second finishing mill in the first and second finishing mill groups is 15 mm, and the base circle diameter corresponding to the pass profile of the fourth finishing mill in the first and second finishing mill groups is 12 mm.

4. The high-speed bar single-pass production line according to claim 2, characterized in that: Each pre-finishing mill in the first line pre-finishing mill group and the second line pre-finishing mill group is arranged in a horizontal and vertical alternating manner, and each pre-finishing mill is driven by a separate motor; Each finishing mill in the first line finishing mill group, the second line finishing mill group, the third line finishing mill group and the fourth line finishing mill group is arranged crosswise at 45 degrees.

5. The high-speed bar single-pass production line according to claim 2, characterized in that: The cross-sectional size of the raw material is 150mm×150mm. The roughing mill consists of six roughing mills and adopts an extended pass system. The intermediate rolling mill group includes six intermediate rolling mills. The rolls of the first intermediate rolling mill are flat rolls. The hole types of the second to sixth intermediate rolling mills are vertical roll edge hole type, pre-slitting hole type, slitting hole type, slitting elliptical hole type and slitting circular hole type respectively. The sixth intermediate rolling mill is the rolling mill located at the end of the rolling direction in the intermediate rolling mill group.

6. The high-speed bar single-pass production line according to claim 5, characterized in that: The extended hole type system is a box type system, a diamond-square system, a combination of a box type system and an ellipse-circle system, or a combination of a diamond-square system and an ellipse-circle system.

7. The high-speed bar single-pass production line according to claim 5, characterized in that: The roughing mills in the roughing mill group are arranged alternately in horizontal and vertical order, and each roughing mill is driven by a separate motor; the intermediate rolling mills in the intermediate rolling mill group are arranged in horizontal-vertical-horizontal-horizontal-horizontal-horizontal order, and each intermediate rolling mill is driven by a separate motor.

8. The high-speed bar single-pass production line according to claim 1, characterized in that: A flying shear is respectively provided between the roughing mill group and the intermediate rolling mill group, between the intermediate rolling mill group and the first line pre-finishing rolling mill group and the second line pre-finishing rolling mill group, between the first line pre-finishing rolling mill group and the first line finishing rolling mill group, between the first line finishing rolling mill group and the third line finishing rolling mill group, between the second line pre-finishing rolling mill group and the second line finishing rolling mill group, and between the second line finishing rolling mill group and the fourth line finishing rolling mill group; Between the third-line finishing mill group and the fourth-line finishing mill group and the high-speed steel feeding device, a flying shear and a double-length flying shear are sequentially provided along the rolling direction.

9. The high-speed bar single-pass production line according to claim 8, characterized in that: Cooling water tanks are respectively provided between the intermediate rolling mill group and the first line pre-finishing rolling mill group and the second line pre-finishing rolling mill group and after the corresponding flying shears; Cooling water tanks are respectively provided between the first line pre-finishing mill group and the first line finishing mill group, between the first line finishing mill group and the third line finishing mill group, between the second line pre-finishing mill group and the second line finishing mill group, between the second line finishing mill group and the fourth line finishing mill group, between the third line finishing mill group and the fourth line finishing mill group and the high-speed steel feeding device, and in front of the corresponding flying shears.

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