Common pass type, rolling equipment and rolling method for single-line rolling line bars before finished products

Abstract

The present invention provides a common hole type before the finished product of a single-line rolling line bar, a rolling device and a rolling method. The common hole type before the finished product comprises: an upper rolling groove and a lower rolling groove with the same structure, the upper rolling groove comprises a groove bottom and two side walls, one end of the side wall extends to the notch plane of the roller gap, and the other end of the side wall is connected to the groove bottom, the groove bottom is formed by sequentially connecting a first circular arc, a second circular arc and a third circular arc, the second circular arc protrudes toward the inner side of the groove bottom, has better clamping force and friction force on the rolled piece, and can effectively prevent the rolled piece from moving back and forth along the axis direction of the roller; before the rolled piece is rolled to the finished product through box-type holes, round holes, elliptical holes, and round hole extension hole type equipment, a set of the same hole types are used, and finally standard threaded steel bars are rolled through different finished product hole types; the present invention provides an efficient, stable, and cost-saving rolling process hole type sharing design, which reduces the frequent replacement of frames, reduces labor intensity, reduces process downtime, and improves rolling stability.

Description

Technical Field

[0001] The invention belongs to the technical field of rod and wire process pass design, and in particular relates to a common pass before the finished product of a single-line rolling line bar, a rolling device and a rolling method. Background Art

[0002] In the production of bars and wires, in order to meet customers' product needs, especially when the demand for large-sized single-line rebar (i.e. single-line rolled rebar) is relatively small, the replacement of large-sized products will be more frequent. Frequent specification changes and rolling mill loading and unloading will affect the rolling efficiency and stability.

[0003] Therefore, in order to address a series of problems such as the small demand for large-size single-wire bar products, frequent specification changes, and rolling mill loading and unloading that will affect the rolling efficiency and rolling stability, it is necessary to provide a technical solution to solve the shortcomings of the existing technology. Summary of the invention

[0004] The purpose of the present invention is to realize the sharing of rolling pass profiles and process integration of single-wire rods and wires with similar specifications before the finished product, reduce the frequent replacement of racks during specification change, reduce labor intensity, reduce process downtime, and improve rolling stability. In order to achieve the above purpose, the present invention provides the following technical solutions:

[0005] The present invention provides a common hole profile before the finished product of a single-line rolling line bar, the common hole profile before the finished product comprises: an upper rolling groove and a lower rolling groove which are arranged opposite to each other perpendicular to the axis of the rolling roller, and the structures of the upper rolling groove and the lower rolling groove are the same; the upper rolling groove comprises: a groove bottom and two side walls, one end of each of the side walls extends to the notch plane of the roll gap, and the other end of each of the side walls is connected to the groove bottom; the groove bottom is formed by connecting a first circular arc, a second circular arc and a third circular arc in sequence, the centers of the first circular arc and the third circular arc are inside the common hole profile before the finished product, the center of the second circular arc is outside the common hole profile before the finished product, the second circular arc protrudes toward the inner side of the groove bottom of the common hole profile before the finished product, and the first circular arc and the third circular arc protrude toward the outer side of the groove bottom of the common hole profile before the finished product.

[0006] According to the above-mentioned common hole profile before the finished product of the single-line rolling line bar, preferably, one end of the side wall is connected to the notch plane of the roll gap through a notch arc transition.

[0007] According to the above-mentioned common hole profile before the finished product of the single-line rolling line bar, preferably, the second arc is connected to the two side walls through the first arc and the third arc arc transition respectively.

[0008] According to the above-mentioned common hole type before the finished product of the single-line rolling line bar, preferably, the upper rolling groove and the lower rolling groove are symmetrically arranged about the axis of the rolling roller; the first arc and the third arc are symmetrically arranged about the angular bisector of the second arc.

[0009] According to the above-mentioned common pass profile before the finished product of the single-line rolling line bar, preferably, the angular bisector of the second circular arc is perpendicular to the axis of the rolling roller.

[0010] According to the above-mentioned common pass profile before the finished product of the single-line rolling line bar, preferably, the expansion angle of the common pass profile before the finished product is 28° to 32°.

[0011] The present invention provides a rolling equipment for single-line rolling line bars, the rolling equipment comprising: a rough rolling mill group, an intermediate rolling mill group and a finishing rolling mill group; the rough rolling mill group has a plurality of rough rolling hole profiles, the intermediate rolling mill group has a plurality of intermediate rolling hole profiles, the finishing rolling mill group comprises: a pre-finished product rolling frame with a pre-finished product hole profile and a finished product rolling frame with a finished product hole profile; the pre-finished product hole profile is the above-mentioned pre-finished product common hole profile.

[0012] According to the above-mentioned single-line rolling line bar rolling equipment, as a preference, the plurality of rough rolling hole profiles are sequentially the first pass hole profile, the second pass hole profile, the third pass hole profile, the fourth pass hole profile, the fifth pass hole profile, and the sixth pass hole profile along the rolling direction; the first pass hole profile and the second pass hole profile are both box-type hole profiles, the fourth pass hole profile and the sixth pass hole profile are both circular hole profiles, the third pass hole profile and the The hole profiles for the 5th pass are all elliptical hole profiles; the multiple hole profiles for intermediate rolling are the 7th pass hole profile, the 8th pass hole profile, the 9th pass hole profile, the 10th pass hole profile, the 11th pass hole profile, and the 12th pass hole profile along the rolling direction; the 7th pass hole profile, the 9th pass hole profile and the 11th pass hole profile are all elliptical hole profiles, and the 8th pass hole profile, the 10th pass hole profile and the 12th pass hole profile are all circular hole profiles.

[0013] The present invention also provides a method for rolling two-specification wire rods according to the above-mentioned single-line rolling wire rod rolling equipment, the method comprising:

[0014] Step S1, heating the first rolled piece;

[0015] Step S2, the first rolled piece that has been heated is subjected to rough rolling by the rough rolling mill group;

[0016] Step S3, the rough-rolled first rolled piece is subjected to intermediate rolling by the intermediate rolling mill group;

[0017] Step S4, the first rolled piece after intermediate rolling is subjected to finish rolling by the pre-finished product rolling stand of the finishing mill group and the finished product rolling stand of the finishing mill group with a first finished product pass profile, to obtain a first finished product with a specification, wherein the first finished product corresponds to the first finished product pass profile;

[0018] Step S5, heating the second rolled piece;

[0019] Step S6, the second rolled piece that has been heated is subjected to rough rolling by the rough rolling mill group;

[0020] Step S7, the second rolled piece after rough rolling is subjected to intermediate rolling by the intermediate rolling mill group;

[0021] Step S8, the second rolled piece after intermediate rolling is subjected to finish rolling by the pre-finished product rolling stand of the finishing mill group and the finished product rolling stand of the finishing mill group with a second finished product pass profile to obtain a second finished product with another specification, wherein the second finished product corresponds to the second finished product pass profile;

[0022] In the rolling process of the first finished product and the second finished product, the corresponding rolled piece profiles are controlled by roller gap pressure release.

[0023] According to the above-mentioned single-wire rolling method for wire rods, preferably, the first finished product is Φ28 threaded steel bar, and the second finished product is Φ32 threaded steel bar.

[0024] Compared with the closest prior art, the technical solution provided by the present invention has the following excellent effects:

[0025] 1. The present invention realizes the sharing of the pass type of the rolling stand except the finished product stand and the integration of the equipment and method, and adjusts the size of the rolled piece by pressing and releasing the roll gap of the rolling mill stand before the finished product, thereby realizing the control of the rolled piece before the finished product;

[0026] 2. The design of combined arc bottom is adopted in the hole type before the finished product in the present invention, which is conducive to controlling the stability of the rolled piece. According to the law of metal flow, the groove bottom with convex arc is preset in the hole type before the finished product, so that the rolled piece before the finished product has a full and regular shape. When entering the hole type of the finished product, the transverse ribs of the finished product can be filled and the longitudinal ribs of the finished product can be effectively prevented from being too large.

[0027] 3. The second arc of the finished product front hole profile of the present invention bulges toward the inner side of the groove bottom, and the convex arc hole profile has better clamping force and friction force on the incoming material than the flat bottom groove bottom hole profile, which can effectively prevent the rolled piece from moving back and forth along the axis of the roller, and ensure that the rolled piece enters the finished product stand stably along the rolling direction;

[0028] 4. The present invention provides an efficient, stable and cost-saving method for rolling two types of threaded steel bars, aiming to realize the sharing of rolling pass profiles before the finished products of single-wire bars and wires with similar specifications and the integration of equipment and methods, reduce the frequent replacement of racks during specification change, reduce labor intensity, reduce process downtime, and improve rolling stability;

[0029] 5. When assembling the wire rod rack in the present invention, the rack assembly amount is reduced, and when processing the rolls, the number of spare rolls is reduced. The front hole profile of the finished product in the present invention is shallower than the bottom depth of the original hole profile. Therefore, when the amount of steel passing through a single groove is the same, the amount of roll rework is reduced, the number of reworks is increased, and the roll consumption is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic diagram of the roughing mill pass in an embodiment of the present invention;

[0031] Figure 2 Schematic diagram of the pass type of the intermediate rolling mill in the embodiment of the present invention;

[0032] Figure 3 Schematic diagram of the pass type of the finishing mill in the embodiment of the present invention;

[0033] Figure 4 This is a schematic diagram of the front hole type of the finished product in an embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram of the Φ28 finished hole type in an embodiment of the present invention;

[0035] Figure 6 It is a schematic diagram of the Φ32 finished hole type in an embodiment of the present invention.

[0036] In the figure: 1, the first pass hole shape; 2, the second pass hole shape; 3, the third pass hole shape;

[0037] 4. The hole type of the 4th pass; 5. The hole type of the 5th pass; 6. The hole type of the 6th pass; 7. The hole type of the 7th pass; 8. The hole type of the 8th pass; 9. The hole type of the 9th pass; 10. The hole type of the 10th pass; 11. The hole type of the 11th pass; 12. The hole type of the 12th pass; 13. The hole type before the finished product; 14. The hole type of the finished product; 141. The hole type of the Φ28 finished product; 142. The hole type of the Φ32 finished product; 101. The first arc; 102. The second arc; 103. The third arc; 106. The bottom of the groove; 107. The side wall; is the expansion angle; H is the groove bottom spacing; h is the roller gap of the finished product front hole profile, h1 is the roller gap of the finished product hole profile; b is the width of the finished product front hole profile; is the arc angle of the finished slot; R1 is the radius of the first arc and the third arc; R2 is the radius of the second arc; Φ1 is the inner diameter of the Φ28 finished hole; Φ2 is the inner diameter of the Φ32 finished hole; R3 is the slot arc radius of the Φ28 finished hole; R4 is the slot arc radius of the Φ32 finished hole. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0039] In the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention. The terms "connected" and "connected" used in the present invention should be understood in a broad sense. For example, they can be fixed connections or detachable connections; they can be directly connected or indirectly connected through intermediate components. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0040] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0041] The present invention provides a common pass before the finished product of a single-line rolling line bar, the common pass before the finished product comprises: an upper rolling groove and a lower rolling groove which are arranged opposite to each other perpendicular to the axis of a rolling roller, and the structures of the upper rolling groove and the lower rolling groove are the same; the upper rolling groove comprises a groove bottom 106 and two side walls 107, one end of each side wall 107 extends to the notch plane of a roll gap, and the other end of each side wall 107 is connected to the groove bottom 106; the groove bottom 106 is formed by sequentially connecting a first circular arc 101, a second circular arc 102 and a third circular arc 103, the center of the first circular arc 101 and the center of the third circular arc 103 are inside the common pass before the finished product, the center of the second circular arc 102 is outside the common pass before the finished product, the second circular arc 102 protrudes toward the inner side of the groove bottom 106 of the common pass before the finished product, and the first circular arc 101 and the third circular arc 103 protrude toward the outer side of the groove bottom 106 of the common pass before the finished product.

[0042] The common hole type before the finished product in the present invention adopts a combined arc bottom design, which is conducive to controlling the stability of the rolled piece. According to the law of metal flow, a groove bottom 106 with a convex arc is preset in the hole type before the finished product, which can make the material type before the finished product have a full and regular shape, and can effectively prevent the longitudinal ribs of the finished product from being too large while filling the transverse ribs of the finished product when entering the hole type of the finished product. By setting the common hole type before the finished product, wire rods with the same rolling pass and the same rolling hole type before being rolled by the rolling mill frame with the hole type before the finished product can share a set of rolling holes before the finished product, reducing the frequent replacement of the rolling mill frame during the specification change process, reducing labor intensity, reducing process downtime, and improving rolling stability.

[0043] Furthermore, the upper rolling groove and the lower rolling groove are symmetrically arranged about the axis of the roller, and the first arc 101 and the third arc 103 are symmetrically arranged about the angular bisector of the second arc 102. The angular bisector of the second arc is perpendicular to the axis of the roller.

[0044] Furthermore, in order to control the stability of the rolled piece material, the second arc 102 is connected to the two side walls 107 by the first arc 101 and the third arc 103 respectively, and one end of the side wall 107 is connected to the notch plane of the roll gap by a notch arc transition; the side wall 107 can clamp the rolled piece, avoiding defects such as torsion caused by the lack of side walls 107 to clamp the rolled piece in the existing hole type, and in severe cases, the rolling cannot be continued, so that the rolling process is stable and the efficiency is significantly improved.

[0045] The second arc 102 in the common hole profile before the finished product protrudes toward the inner side of the groove bottom 106. Compared with the flat-bottom groove bottom 106 hole profile, the protruding arc hole profile has better clamping force and friction force on the incoming material, which can effectively prevent the rolled piece from moving back and forth along the axis of the roller, and ensure that the rolled piece enters the finished product frame stably along the rolling direction.

[0046] Furthermore, in order to facilitate the stripping of the rolled piece and the correct entry into the pass, the expansion angle of the common pass before the finished product is The expansion angle (or side wall bevel angle) of the front hole type of the preferred finished product of the present invention is between 28° and 32°, for example, 29°, 30°, 31°. The expansion angle is 30°, that is, the angle formed between the side wall of the hole and the vertical direction (the vertical direction is the direction perpendicular to the axis of the roll), the radius R1 of the first arc 101 and the third arc 103 is 13 mm, the radius R2 of the second arc 102 is 83.25 mm, the distance H between the upper groove bottom and the lower groove bottom is 22 mm, the width b of the hole before the finished product is 48 mm, and the roll gap width h is 5 mm; the groove bottom depth of the common hole before the finished product in the present invention is shallower than that of the original hole. When the amount of steel passing through a single groove is the same, the amount of roll rework is reduced, thereby reducing roll consumption.

[0047] The present invention also provides a rolling equipment for single-line rolling line bars, the rolling equipment comprising a rough rolling mill group, an intermediate rolling mill group and a finishing rolling mill group, the rough rolling mill group having a plurality of rough rolling hole profiles, the intermediate rolling mill group having a plurality of intermediate rolling hole profiles, the finishing rolling mill group comprising a pre-finished product rolling frame having a pre-finished product hole profile and a finished product rolling frame having a finished product hole profile.

[0048] Further, in an embodiment of the present invention, a plurality of rough rolling hole profiles are, along the rolling direction, the 1st pass hole profile 1, the 2nd pass hole profile 2, the 3rd pass hole profile 3, the 4th pass hole profile 4, the 5th pass hole profile 5, and the 6th pass hole profile 6; a plurality of intermediate rolling hole profiles are, along the rolling direction, the 7th pass hole profile 7, the 8th pass hole profile 8, the 9th pass hole profile 9, the 10th pass hole profile 10, the 11th pass hole profile 11, and the 12th pass hole profile 12.

[0049] The 1st pass hole type 1 and the 2nd pass hole type 2 are both box-type hole types, the 4th pass hole type 4 and the 6th pass hole type 6 are both circular hole types, the 3rd pass hole type 3 and the 5th pass hole type 5 are both elliptical hole types; the 7th pass hole type 7, the 9th pass hole type 9 and the 11th pass hole type 11 are all elliptical hole types, the 8th pass hole type 8, the 10th pass hole type 10 and the 12th pass hole type 12 are all circular hole types.

[0050] The finished pass 14 in the embodiment of the present invention comprises an upper groove bottom, a lower groove bottom and longitudinal ribs. One end of the finished pass 14 forms a free expansion area with the notch of the finished pass 14. One end of the side wall is connected to the notch plane of the roll gap through a finished notch arc. The angle between the tangent of the arc and the notch plane is The angle of the roller is 15°, and the roller gap h1 of the finished hole is 3mm.

[0051] Further, the finished hole profile 14 in the embodiment of the present invention includes a Φ28 finished hole profile and a Φ32 finished hole profile, the radius R3 of the finished notch arc of the Φ28 finished hole profile is 2 mm, and the inner diameter Φ1 of the Φ28 finished hole profile is 27.2 mm; the radius R4 of the finished notch arc of the Φ32 finished hole profile is 2.5 mm, and the inner diameter Φ2 of the Φ32 finished hole profile is 30.9 mm; according to actual production needs, which specification of threaded steel is required, the previously rolled workpiece is introduced into the required finished hole profile 14 in the last production process. In other embodiments, the finished hole profile can also correspond to wire rods of other specifications. The wire rods are all wire rods rolled by a single wire.

[0052] The rolling equipment for single-line rolling line bars of the present invention uses a set of pre-finished hole-type equipment to roll out two kinds of threaded steel bars, reduces the frequent replacement of frames, reduces labor intensity, reduces process downtime, improves rolling stability, reduces the number of spare rolls during roll processing, and reduces roll consumption.

[0053] According to the above-mentioned common pass profile before the finished product of the single-line rolling line bar and the rolling equipment of the single-line rolling line bar, the present invention also provides a method for rolling the line bar, which method includes the following steps:

[0054] Step S1, heating the first rolled piece;

[0055] Step S2, the first rolled piece that has been heated is subjected to rough rolling by a rough rolling mill;

[0056] Step S3, the rough-rolled first rolled piece is subjected to intermediate rolling by an intermediate rolling mill group;

[0057] Step S4, the first rolled piece after intermediate rolling is subjected to finish rolling by a pre-finished product rolling stand of a finishing mill and a finished product rolling stand with a first finished product pass profile of the finishing mill to obtain a first finished product with a specification, the first finished product corresponding to the first finished product pass profile;

[0058] Step S5, heating the second rolled piece;

[0059] Step S6, the second rolled piece after the heat treatment is subjected to rough rolling by a rough rolling mill;

[0060] Step S7, the second rolled piece after rough rolling is subjected to intermediate rolling by an intermediate rolling mill group;

[0061] Step S8, the second rolled piece after intermediate rolling is subjected to finish rolling by a pre-finished product rolling stand of a finishing mill and a finished product rolling stand with a second finished product pass profile of the finishing mill to obtain a second finished product with another specification, the second finished product corresponding to the second finished product pass profile;

[0062] In the rolling process of the first finished product and the second finished product, the corresponding rolled piece profiles are controlled by roller gap pressure release.

[0063] Before the rolled pieces corresponding to the two specifications are rolled into their corresponding finished products, the same set of hole profiles are used, and then when they reach the finished product pass, they are rolled into two specifications of finished products through different finished product hole profiles. In other words, except for the finished product rolling mill frame, the hole profiles of other rolling mill frames are shared.

[0064] Furthermore, the first finished product is Φ28 threaded steel bar, and the second finished product is Φ32 threaded steel bar.

[0065] The present invention takes the production of Φ28 and Φ32 threaded steel bars as an example. In actual production, the rolling process of Φ28 and Φ32 threaded steel bars is a 14-pass forming process as shown in Table 1. The rolling pass profiles of the first 12 passes are the same, and the cross-sectional areas of the front profiles of the two specifications of finished products are similar.

[0066] Table 1

[0067]

[0068] On this basis, the hole profile before the finished product is redesigned, that is, the 13th pass of the strip indicated in Table 1. The hole profile before the finished product adopts a hole profile design of a combined arc bottom. The rolling material profile is controlled by pressing and releasing the roll gap of the rolling mill frame, thereby realizing the integration of the rolling process of Φ28 and Φ32 rebars. In the 14-pass side rolling forming process, the rolling hole profiles of the first 13 passes are shared, that is, by adjusting the groove bottom spacing of the roller hole profile before the new finished product, the material profile before the rolled product of different specifications is controlled. The effect of adjusting the rolling hole profile of the 13th pass of the shared hole profile before the finished product is shown in Table 2.

[0069] Table 2

[0070]

[0071] By comparing the data of the common pass type of the 13th pass in Table 1 and Table 2, the common rolling pass type system before the finished product of single-wire rods and wires with similar specifications is realized, and the size of the incoming material type is adjusted by pressing and releasing the roll gap of the rolling mill frame before the finished product, so as to realize the control of the material type before the finished product, reduce the frequent replacement of the frame during the specification change process, reduce labor intensity, reduce process downtime, improve work efficiency, and improve rolling stability. At the same time, when assembling the wire rod frame in the present invention, the frame assembly amount is reduced, and when the roll is processed, the number of spare rolls is reduced. It should be noted that in Table 1 and Table 2, the 3.5mm corresponding to the 14th pass should be the roll gap value, not the groove bottom spacing value.

[0072] The present invention takes the rolling of Φ28 and Φ32 single-wire threaded steel bars as an example. The specifications of the two threaded steel bars of the finished base circle are similar, and they have the same 14-pass forming process. After the hole type before the finished product is redesigned, the rolling stand hole type system sharing and process integration are realized. The rolled piece is heated, rolled by the rough rolling unit, the intermediate rolling unit and the finishing rolling unit, and rolled by the box hole, round hole, elliptical hole, and round hole extension hole type system before the finished product. A set of the same hole type is used, and finally when it reaches the finished product pass, different finished product hole types are used to roll out threaded steel bars that meet the standard size requirements.

[0073] In summary, two single-line threaded steel bar rolling processes of similar specifications share a set of hole equipment, realizing the sharing of rolling frame hole profiles and process integration except for the finished product frame (the frame has a finished product hole profile), and adjusting the size of the incoming material profile by pressing and releasing the roll gap of the rolling mill frame before the finished product, thereby realizing the control of the material profile before the finished product; the hole profile before the finished product in the present invention adopts a combined arc bottom design, which is beneficial to controlling the stability of the material profile, and according to the law of metal flow, a groove bottom with a convex arc is preset in the hole profile before the finished product, so that the material profile before the finished product can have a full and regular shape, and when entering the finished product hole profile, the finished product transverse ribs can be filled while effectively avoiding the finished product longitudinal ribs from being too large; the second arc of the hole profile before the finished product in the present invention protrudes toward the inner side of the groove bottom, and has better clamping of the incoming material than the groove bottom hole profile with a flat bottom. The holding force and friction force can effectively prevent the rolled piece from moving back and forth along the axis of the roller, and ensure that the rolled piece enters the finished product frame stably along the rolling direction; the present invention provides an efficient, stable and cost-saving design of two specifications of threaded steel bar rolling process hole type sharing, aiming to realize the sharing of pre-finished product rolling hole type and process integration of single-wire rod and wire with similar specifications, reduce the frequent replacement of the frame during the specification change process, reduce labor intensity, reduce process downtime, and improve rolling stability; when the wire rod frame in the present invention is assembled, the frame assembly amount is reduced, and when the roller is processed, the number of spare rollers is reduced. The pre-finished product hole type in the present invention is shallower than the original hole type groove bottom depth. Therefore, under the condition of the same single groove steel passing amount, the roller rework amount is reduced, the number of rework times is increased, and the roller consumption is reduced.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are within the scope of protection of the pending claims of the present invention.

Claims

1. A method for rolling two types of wire rods by a rolling equipment for rolling single-line wire rods, the rolling equipment comprising: Roughing mill, intermediate rolling mill and finishing mill; The rough rolling mill group has a plurality of rough rolling pass profiles, the intermediate rolling mill group has a plurality of intermediate rolling pass profiles, and the finishing mill group includes: a pre-finished product rolling stand with a pre-finished product pass profile and a finished product rolling stand with a finished product pass profile; The pre-finished product hole profile is a pre-finished product common hole profile; the pre-finished product common hole profile comprises: an upper rolling groove and a lower rolling groove which are arranged opposite to each other perpendicular to the roller axis, and the upper rolling groove and the lower rolling groove have the same structure; the upper rolling groove comprises: a groove bottom and two side walls, one end of each of the side walls extends to the notch plane of the roller gap, and the other end of each of the side walls is connected to the groove bottom; the groove bottom is formed by connecting the first arc, the second arc and the third arc in sequence, the centers of the first arc and the third arc are inside the pre-finished product common hole profile, the center of the second arc is outside the pre-finished product common hole profile, the second arc protrudes to the inner side of the groove bottom of the pre-finished product common hole profile, and the first arc and the third arc protrude to the outer side of the groove bottom of the pre-finished product common hole profile; Characterized in that the method comprises: Step S1, heating the first rolled piece; Step S2, the first rolled piece that has been heated is subjected to rough rolling by the rough rolling mill group; Step S3, the rough-rolled first rolled piece is subjected to intermediate rolling by the intermediate rolling mill group; Step S4, the first rolled piece after intermediate rolling is subjected to finish rolling by the pre-finished product rolling stand of the finishing mill group and the finished product rolling stand of the finishing mill group having a first finished product pass profile, to obtain a first finished product having a specification, wherein the first finished product corresponds to the first finished product pass profile; Step S5, heating the second rolled piece; Step S6, the second rolled piece that has been heated is subjected to rough rolling by the rough rolling mill group; Step S7, the second rolled piece after rough rolling is subjected to intermediate rolling by the intermediate rolling mill group; Step S8, the second rolled piece after intermediate rolling is subjected to finish rolling by the pre-finished product rolling stand of the finishing mill group and the finished product rolling stand of the finishing mill group with a second finished product pass profile to obtain a second finished product with another specification, wherein the second finished product corresponds to the second finished product pass profile; In the rolling process of the first finished product and the second finished product, the corresponding rolled piece profiles are controlled by roller gap pressure release.

2. The method for rolling two-specification wire rods by a single-line rolling equipment according to claim 1, characterized in that: One end of the side wall is connected to the notch plane of the roller gap through a notch arc transition.

3. The method for rolling two-specification wire rods by a single-line rolling equipment according to claim 1, characterized in that: The second circular arc is connected to the two side walls through arc-shaped transitions of the first circular arc and the third circular arc respectively.

4. The method for rolling two-specification wire rods by a single-line rolling equipment according to claim 1, characterized in that: The upper rolling groove and the lower rolling groove are symmetrically arranged about the axis of the roller; The first circular arc and the third circular arc are symmetrically arranged about an angle bisector of the second circular arc.

5. The method for rolling two-specification wire rods by a single-line rolling equipment according to claim 4, characterized in that: The angle bisector of the second arc is perpendicular to the roller axis.

6. The method for rolling two-specification wire rods by a single-line rolling equipment according to claim 1, characterized in that: The expansion angle of the common hole type before the finished product is 28°~32°, and the expansion angle is the angle formed between the side wall of the hole type and the vertical direction, and the vertical direction is the direction perpendicular to the axis of the roller.

7. The method for rolling two-specification wire rods by a single-line rolling equipment according to claim 1, characterized in that: The plurality of rough rolling pass shapes are sequentially a first pass pass shape, a second pass pass shape, a third pass pass shape, a fourth pass pass shape, a fifth pass pass shape, and a sixth pass pass shape along the rolling direction; The first pass hole profile and the second pass hole profile are both box-shaped hole profiles, the fourth pass hole profile and the sixth pass hole profile are both circular hole profiles, and the third pass hole profile and the fifth pass hole profile are both elliptical hole profiles; The plurality of intermediate rolling pass types are, in order along the rolling direction, the 7th pass type, the 8th pass type, the 9th pass type, the 10th pass type, the 11th pass type, and the 12th pass type; The 7th pass hole profile, the 9th pass hole profile and the 11th pass hole profile are all elliptical hole profiles, and the 8th pass hole profile, the 10th pass hole profile and the 12th pass hole profile are all circular hole profiles.

8. The method for rolling two-specification wire rods by a single-line rolling equipment according to claim 1, characterized in that: The first finished product is Φ28 threaded steel bar, and the second finished product is Φ32 threaded steel bar.

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