A three-side rib cold-rolled ribbed steel bar rolling hole shape system

Abstract

A rolling pass system for three-sided ribbed cold-rolled steel bars includes a reduction rolling mill and rolls. The reduction rolling process employs two reduction mills, both of which are two-roll mills. The first reduction mill uses one of three pass shapes on the two rolls: Option A: Both rolls have corresponding semi-elliptical grooves, resulting in elliptical cross-sections; Option B: Both rolls have corresponding V-grooves with obtuse angles at the base, resulting in triangular cross-sections; Option C: Both rolls are cylindrical, and the steel bar is rolled into a flat cross-section after passing through the first reduction mill. The second reduction mill has one cylindrical roll and the other roll with a V-groove, resulting in a triangular cross-section after passing through the second reduction mill. This system can reduce the production cost of three-sided ribbed cold-rolled steel bars.

Description

Technical Field

[0001] This utility model relates to the production of three-sided ribbed steel bars, and in particular to a rolling die system for three-sided ribbed cold-rolled steel bars, belonging to the field of cold-rolled steel bar technology. Background Technology

[0002] Steel rolling is the process of rolling steel billets into a specific shape using the continuous rotation of rolls. The rolls are mounted on a rolling mill. For two rolls arranged vertically, one roll is usually adjustable in height, allowing for adjustment of the distance between the two rolls during rebar feeding. During rolling, the two rolls are brought closer together. The rolls have grooves etched into their surfaces. To roll a product into a specific shape, several passes of the rolling mill are generally required. The shape and size of the grooves on the rolls, varying according to a certain pattern across multiple passes, are conventionally referred to in the industry as a pass (type) system. Specifically, in the production of three-sided ribbed cold-rolled steel bars, two passes are currently generally used. Both passes employ a three-roll mill (or a Y-type mill), such as... Figure 4 The first pass is called reduction rolling. Three rolls are evenly distributed circumferentially. Through reduction rolling, the cross-sectional area of ​​the raw material is compressed, inducing plastic deformation, and simultaneously rolling the circular cross-section of the steel bar into a triangular cross-section, creating conditions for forming rolling. The surface of the reduction rolling roll grooves is smooth and without transverse ribs. The second pass is called forming rolling. The grooves are engraved with evenly distributed recessed ribs circumferentially. The three forming rolling rolls are also evenly distributed circumferentially, but they intersect the reduction rolling rolls at a 60-degree angle. This means that during forming rolling, rolling force is applied to the three sharp corners of the triangular steel bar formed by reduction, allowing the metal to flow and fill the transverse ribs, simultaneously rolling the finished steel bar into a circular cross-section. Forming rolling can only be done in one pass because the recessed ribs on the forming roll rings make it technically impossible to achieve complete overlap in multi-pass forming rolling. Therefore, it can only be rolled in one pass, forming in one step. The rolling of three-sided ribbed cold-rolled steel bars needs to be completed on a three-roll mill (or Y-type mill). Due to the constraint that the three rolls must be evenly distributed in the circumferential direction, the mill is more complex and larger than the traditional two-roll mill, resulting in higher operating and maintenance costs, and making it difficult and time-consuming to change the roll specifications. This leads to high equipment, maintenance, and production costs. Summary of the Invention

[0003] The purpose of this invention is to overcome the aforementioned problems in the current three-sided ribbed cold-rolled ribbed steel bar rolling process, which uses a three-roll mill for both rolling passes, and to provide a rolling pass system for three-sided ribbed cold-rolled ribbed steel bars.

[0004] To achieve the purpose of this utility model, the following technical solution is adopted: a three-sided ribbed steel bar rolling die system, including a reduction rolling mill and rolls. The reduction rolling mill uses two reduction mills, both of which are two-roll mills. The die shape on the two rolls of the first reduction mill adopts one of the following three schemes: Scheme A: Both rolls are machined with corresponding semi-elliptical grooves, and the die shape of the cross-section of the two rolls is elliptical. The steel bar is rolled into an elliptical cross-section after passing through the first reduction mill; Scheme B: Both rolls are machined with corresponding V-shaped grooves, the bottom angle of the V-shaped grooves is obtuse, and the die shape of the cross-section of the two rolls is triangular. The steel bar is rolled into a quadrilateral cross-section after passing through the first reduction mill; Scheme C: Both rolls are cylindrical, and the steel bar is rolled into a flat cross-section after passing through the first reduction mill; The die shape on the second reduction mill is: one roll is cylindrical, and the other roll has a V-shaped groove. After passing through the second reduction mill, the steel bar is rolled into a triangular cross-section.

[0005] Furthermore, in Scheme A, the ratio of the major axis to the minor axis of the ellipse is 1:1.6-2.2.

[0006] Furthermore, in Scheme B, the ratio of the long diagonal to the short diagonal of the quadrilateral is 1:1.5-2.

[0007] Furthermore, in scheme C, the ratio of the maximum width to the thickness of the deformation is 1:2.5-3.2.

[0008] The positive and beneficial technical effects of this utility model are as follows: the three-sided ribbed cold-rolled steel bars adopt this die system in the reduction rolling process, and the triangular cross section is rolled out by two reduction rolling mills. Compared with the existing one-roll three-roll rolling mill, the two-roll rolling mill has a simpler structure and more mature technology. The equipment cost and maintenance cost of two two-roll rolling mills are lower than that of one three-roll rolling mill. The replacement of rolls is quick and convenient, which can reduce the production cost of three-sided ribbed cold-rolled steel bars. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of scheme A.

[0010] Figure 2 This is a schematic diagram of Scheme B.

[0011] Figure 3 This is a schematic diagram of scheme C.

[0012] Figure 4 This is a schematic diagram of an existing two-pass rolling mill that uses a three-roll mill. Detailed Implementation

[0013] To more fully explain the implementation of this utility model, implementation examples are provided. These implementation examples are merely illustrative of this utility model and do not limit its scope.

[0014] The present invention will be further explained in detail with reference to the accompanying drawings, in which the following markings are provided: 1: first reduction mill roll; 2: second mill roll; 3: elliptical cross section; 4: triangular cross section; 5: quadrilateral cross section; 6: flat cross section.

[0015] Figures 1 to 3 In the diagram, 'a' represents the cross-section after the first reduction rolling, and 'b' represents the initial cross-section when feeding into the second reduction rolling. In this embodiment, the major axis of the cross-section after the first reduction rolling is horizontal, while the major axis of the steel bar entering the second reduction rolling is vertical (as shown in 'b'). This method of turning 90 degrees to enter the second reduction rolling mill is existing technology. If necessary, it can be accomplished by setting a guide mechanism between the two reduction rolling mills. 'c' represents the cross-section after the second reduction rolling. The rolling mill, rolls, and the use of two reduction rolling mills involved in this pass system are all existing technologies.

[0016] As shown in the attached figure, a three-sided ribbed steel bar rolling die system includes a reduction rolling process. The reduction rolling process employs two reduction mills, both of which are two-roll mills. In the figure, 1 shows the roll of the first reduction mill, and 2 shows the roll of the second reduction mill. The die shape on the two rolls of the first reduction mill adopts one of the following three schemes: Scheme A: Both rolls are machined with corresponding semi-elliptical grooves, and the die shape of the cross-section of the two rolls is elliptical, with the ratio of the major axis to the minor axis of the ellipse being 1:1.6-2.2. The steel bar is rolled into an elliptical cross-section after passing through the first reduction mill; Scheme 3... Option B: Both rolls are machined with corresponding V-grooves, the base angle of the V-grooves is obtuse, and the cross-section of the two rolls is triangular. After passing through the first reducing mill, the steel bar is rolled into a quadrilateral cross-section; the ratio of the long diagonal to the short diagonal of the quadrilateral is 1:1.5-2. Option C: Both rolls are cylindrical. After passing through the first reducing mill, the steel bar is rolled into a flat cross-section; the ratio of the maximum width to the thickness of the flat cross-section is 1:2.5-3.2. The cross-section of the second reducing mill is: one roll is cylindrical, and the other roll has a V-groove. After passing through the second reducing mill, it is rolled into a triangular cross-section.

[0017] The forming mill located after this pass still uses the existing three-roll mill.

[0018] After a detailed description of the embodiments of this utility model, those skilled in the art will clearly understand that various changes and modifications can be made without departing from the scope and spirit of the above-mentioned patent applications. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this utility model shall fall within the scope of the technical solution of this utility model, and this utility model is not limited to the embodiments of the examples given in the specification.

Claims

1. A three-surface rib cold rolled ribbed steel bar rolling hole shape system comprising a reducing mill and a roll, characterized in that: The reduction rolling process employs a two-pass reduction mill, both of which are two-roll mills. The first reduction mill uses one of three die shapes on its two rolls: Die Shape A: Both rolls have corresponding semi-elliptical grooves, resulting in elliptical cross-sections. The reinforcing bar is rolled into an elliptical cross-section after passing through the first reduction mill. Die Shape B: Both rolls have corresponding V-grooves with obtuse base angles, resulting in triangular cross-sections. The reinforcing bar is rolled into a quadrilateral cross-section after passing through the first reduction mill. Die Shape C: Both rolls are cylindrical, resulting in a flat cross-section after passing through the first reduction mill. The second reduction mill has one cylindrical roll and the other roll with a V-groove, resulting in a triangular cross-section after passing through the second reduction mill.

2. A three-surface rib cold rolled deformed steel bar rolling hole shape system according to claim 1, characterized in that: In Scheme A, the ratio of the major axis to the minor axis of the ellipse is 1:1.6-2.

2.

3. The three-surface rib cold-rolled deformed steel bar rolling hole shape system according to claim 1, characterized in that: In Scheme B, the ratio of the long diagonal to the short diagonal of the quadrilateral is 1:1.5-2.

4. The three-surface rib cold-rolled deformed steel bar rolling hole shape system according to claim 1, characterized in that: In scheme C, the ratio of the maximum width to the thickness of the deformation is 1:2.5-3.2.

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