Two-rod angle channel steel rolling equipment and process

Abstract

The invention belongs to the technical field of channel steel rolling, and particularly discloses two-rod angle channel steel rolling equipment which comprises a heating furnace and a guide plate, the heating furnace is a walking beam type heating furnace and is communicated with a roughing mill through the guide plate, the maximum diameter of a roller of the roughing mill is set to be phi 640 mm, and the roughing mill is communicated with an intermediate mill through the guide plate. The maximum diameter of a roller of the intermediate rolling mill is set to be phi 540 mm, the intermediate rolling mill is communicated with a finishing mill through a guide plate, the maximum diameter of a roller of the finishing mill is set to be phi 440 mm, the finishing mill is communicated with a cooling bed through the guide plate, the cooling bed is communicated with a straightening machine through the guide plate, and the straightening machine is communicated with a cold saw through the guide plate; proper hole patterns are selected for a roughing mill, an intermediate mill and a finishing mill in a bar rolling production line, shearing equipment is replaced with cold sawing equipment, and bars are converted into angle channel steel by replacing part of equipment on the bar rolling production line; the problem that when angle channel steel is rolled through an existing bar rolling production line, the rolling technology and production equipment are greatly different is solved.

Description

Technical Field

[0001] This invention relates to the field of channel steel rolling technology, specifically to a two-bar angle channel steel rolling equipment and process. Background Technology

[0002] The No. 2 bar production line is a steel bar rolling production line. The steel billets are reheated in a furnace to the rolling temperature; then, after descaling, the billets enter a continuous rolling production line consisting of roughing, intermediate, and finishing mills. Through multiple passes and high-precision roll passes, they undergo plastic deformation and controlled cooling to achieve the target specifications. The rolled pieces are then cooled to room temperature on a cooling bed, followed by finishing, shearing, and bundling processes. Angle and channel steel are complex cross-sectional profiles, combining the structural characteristics of both angle and channel steel. Therefore, they are widely used in applications requiring complex stress or high rigidity, such as building steel structures, mechanical frames, bridge components, and heavy equipment bases.

[0003] The second bar mill is a bar production line that produces one bar. Compared with the angle and channel steel production line, there are significant differences in rolling process and rolling tooling. The bar rolling mainly uses a continuous rolling mill with two rolls arranged alternately horizontally and vertically. The rolls are deformed by symmetrical grooves such as circles and ovals engraved on the roll body. For rolling special-shaped materials such as angle and channel steel, a universal rolling mill (a four-roll stand consisting of a pair of horizontal rolls and a pair of vertical rolls) or a special three-roll section steel rolling mill must be used. However, the vertical rolling mill with alternating horizontal and vertical sections cannot press down when the bar rolling production line rolls angle and channel steel, and the deformation rate distribution is difficult. It is necessary to redesign the mill grooves and parameters of each pass. Summary of the Invention

[0004] The purpose of this invention is to provide a rolling equipment and process for two-bar angle channel steel, so as to solve the problem that there are significant differences in rolling process and production equipment when rolling angle channel steel in existing bar rolling production lines.

[0005] To achieve the above objectives, the basic solution provided by this invention is as follows: a two-bar angle channel steel rolling equipment, comprising a heating furnace and guide plates. The heating furnace is a walking beam type heating furnace. The heating furnace is connected to a roughing mill via the guide plates. The maximum diameter of the roughing mill rolls is set to φ640mm. The roughing mill is connected to an intermediate mill via the guide plates. The maximum diameter of the intermediate mill rolls is set to φ540mm. The intermediate mill is connected to a finishing mill via the guide plates. The maximum diameter of the finishing mill rolls is set to φ440mm. The finishing mill is connected to a cooling bed via the guide plates. The cooling bed is connected to a straightening machine via the guide plates. The straightening machine is connected to a cold saw via the guide plates.

[0006] The principle and beneficial effects of this invention are as follows: In use, the steel billet is first heated in a heating furnace. After heating, the steel billet is rolled sequentially through a roughing mill, an intermediate mill, and a finishing mill. The roll gap, rolling speed, and tension of each pass are controlled during the rolling process. The finished angle and channel steel is water-cooled, sheared, and then sent to a cooling bed. After cooling on the cooling bed, the angle and channel steel is sent to a straightening machine. The straightened angle and channel steel is then sent to a cold saw. By selecting appropriate pass types for the roughing mill, intermediate mill, and finishing mill in the bar rolling production line, and replacing the shearing equipment with cold saw equipment, the bar rolling production line can be converted into angle and channel steel, thereby reducing costs.

[0007] Option 2, which is the basic solution of this invention: a rolling equipment and process for two-bar angle channel steel, including the following steps: S1. The steel billet is heated in a heating furnace. During the heating process, the temperature of the heating section, the soaking section and the initial rolling section is controlled. After heating, the steel billet is transported to the roughing mill through guide plates and conveyor rollers. S2. Select the corresponding angle and channel steel cutting pass according to the specifications of the angle and channel steel products. Roll the steel billet with a size of 150mm*150mm into angle and channel steel through 6 passes of roughing mill. Control the elongation coefficient, rolling force and rolling speed during the rolling process. After the rough rolled angle and channel steel is cut, it is transported to the intermediate mill. S3. The rough-rolled angle and channel steel is fed into the corresponding butterfly-shaped mill for intermediate rolling. It is rolled through 4 passes of intermediate rolling mill. During the rolling process, the roll gap, rolling speed and tension of each pass are controlled. The intermediate-rolled angle and channel steel is water-cooled and then transported to the finishing mill. S4. The angle and channel steel after intermediate rolling is fed into the corresponding closed-end finished product roll pass and rolled through a 6-pass finishing mill. During the rolling process, the rolling speed and tension of each pass are controlled. After the finished angle and channel steel is water-cooled and sheared, it is sent to the cooling bed after a delay of 700ms. S5. Control the temperature of the angle and channel steel after finishing rolling and place it on the cooling bed. Cool the high-temperature finished steel evenly and slowly on the cooling bed. Control the parameters of low-level dwell, middle-level dwell, high-level dwell, correction, LastBar delay and rising to the middle level of the cooling bed. The cooled angle and channel steel is sent to the straightening machine. S6. The 10 rollers of the straightening machine are divided into three pre-straightening rollers at the entrance, four main straightening rollers in the middle, and three fine straightening rollers at the exit. The initial pressing amount of the main straightening roller at the entrance is 15%-20% of the profile section thickness, the second roller is 35%-40%, the third roller is 20%, the fourth roller is 15%-10%, and the fifth roller is 5%. The deviation of the pressing amount at different parts of the same section, the straightening speed and the fluctuation of the linear speed are controlled during straightening. The straightened angle and channel steel is then fed into the cold saw. S7. The length range of cold-sawed angle channel steel is 6-12m. The speed of the sawing roller is adjusted according to different fixed lengths. The adjustment accuracy of the fixed length baffle is ±0.1mm. The response delay of the servo motor drive is ≤0.2s. The baffle reset error after each sawing does not exceed 0.05mm.

[0008] Option 3, which is the preferred option of Option 2, involves controlling the temperature of the heating section to be 1000-1150℃, the temperature of the soaking section to be 1030-1170℃, and the initial rolling temperature to be 1070-1130℃ in step S1.

[0009] Option 4, an optimal choice of Option 2, involves controlling the elongation coefficient for each pass between 1.31 and 1.4 in step S2. No rolling force adjustment is performed for passes 1-8. Rolling force adjustment begins from pass 9. The formula for calculating the rolling force is as follows: Where P is the rolling force, μ is the friction coefficient of the steel roll, B is the width of the workpiece before rolling, R is the roll radius, Δh is the reduction, the roll gap of each pass is controlled at 125-170mm, and the rolling speed during roughing is controlled at 0.25-1m / s.

[0010] Option 5, which is the preferred option of Option 2, involves controlling the roll gap of each pass to 10.5-27mm, the rolling speed to 1.2-2.5m / s, and the tension to 60-100mm in step S3.

[0011] Option 6, which is the preferred option of Option 2, involves controlling the roll gap of each pass to 0.75-1.2mm, the rolling speed to 3.5-8m / s, and the tension to 12-18mm in step S4.

[0012] Option 7, which is the preferred option of Option 2, involves controlling the temperature of the upper cooling bed to 970-1030℃ in step S5, controlling the low-level dwell time to 350-400ms, the middle-level dwell time to 210-270ms, the high-level dwell time to 1320-1420ms, the correction time to 4500ms, the LastBar delay to 600ms, and the rise to the middle level to 220-300ms.

[0013] Option 8 is a preferred option of Option 2. In step S6, the deviation of the amount of pressure at different parts of the same cross section is controlled to be ≤0.2mm, the straightening speed is 18-35m / min, the linear speed fluctuation is ≤±1m / min, and a gap of 0.3-0.6mm between the rollers is reserved.

[0014] Option 9, which is a preferred option of Option 2, in step S7, when the fixed length is 6-8m, the sawing roller speed is 1.2-1.5m / s, and when the fixed length is 9-12m, the sawing roller speed is 0.8-1m / s. Attached Figure Description

[0015] Figure 1This is a schematic diagram of the structure of a two-bar angle channel steel rolling equipment and process according to the present invention. Detailed Implementation

[0016] The present invention will be further described in detail below through specific embodiments: The reference numerals in the accompanying drawings include: 1. heating furnace, 2. roughing mill, 3. intermediate mill, 4. finishing mill, 5. cooling bed, 6. straightening machine, and 7. cold saw.

[0017] Example 1 like Figure 1 The image shows a rolling mill for two-bar angle channel steel, comprising a heating furnace and guide plates. The heating furnace is a walking beam type heating furnace. The heating furnace is connected to a roughing mill via the guide plates. The maximum diameter of the roughing mill rolls is set to φ640mm. The roughing mill is connected to an intermediate mill via the guide plates. The maximum diameter of the intermediate mill rolls is set to φ540mm. The intermediate mill is connected to a finishing mill via the guide plates. The maximum diameter of the finishing mill rolls is set to φ440mm. The finishing mill is connected to a cooling bed via the guide plates. The cooling bed is connected to a straightening machine via the guide plates. The straightening machine is connected to a cold saw via the guide plates.

[0018] The implementation method of this embodiment is as follows: In use, the steel billet is first heated in a heating furnace. After heating, the steel billet is rolled sequentially through a roughing mill, an intermediate mill, and a finishing mill. The roll gap, rolling speed, and tension of each pass are controlled during the rolling process. The finished angle and channel steel is water-cooled, sheared, and then sent to a cooling bed. After being cooled on the cooling bed, the angle and channel steel is sent to a straightening machine. The straightened angle and channel steel is then sent to a cold saw. Appropriate pass types are selected for the roughing mill, intermediate mill, and finishing mill in the bar rolling production line, and the shearing equipment is replaced with a cold saw. By replacing some equipment on the bar rolling production line, the bar stock is converted into angle and channel steel, thereby reducing costs.

[0019] Example 2 A rolling mill and process for two-bar angle channel steel includes the following steps: S1. The steel billet is heated in a heating furnace. During the heating process, the temperatures of the heating section, the soaking section and the initial rolling are controlled. The temperature of the heating section is 1000-1150℃, the temperature of the soaking section is 1030-1170℃, and the initial rolling temperature is 1070-1130℃. After heating, the steel billet is transported to the roughing mill through guide plates and conveyor rollers. S2. Select the corresponding cutting pass type for the angle and channel steel according to the product specifications. Roll the 150mm*150mm steel billet into angle and channel steel through a roughing mill in 6 passes. During the rolling process, control the elongation coefficient, rolling force, and rolling speed. The elongation coefficient for each pass is controlled between 1.31 and 1.4. No rolling force adjustment is made for passes 1-8. The rolling force is adjusted from the 9th pass onwards. The formula for calculating the rolling force is: Where P is the rolling force, μ is the friction coefficient of the steel roll, B is the width of the workpiece before rolling, R is the roll radius, Δh is the reduction, the roll gap of each pass is controlled at 125-170mm, the rolling speed during rough rolling is controlled at 0.25-1m / s, and the rough-rolled angle and channel steel is sheared and transported to the intermediate rolling mill. S3. The rough-rolled angle and channel steel is fed into the corresponding butterfly mill for intermediate rolling. It is rolled in 4 passes of intermediate mill. During the rolling process, the roll gap, rolling speed and tension of each pass are controlled. The roll gap of each pass is controlled at 10.5-27mm, the rolling speed is 1.2-2.5m / s, and the tension is controlled at 60-100mm. The intermediate-rolled angle and channel steel is water-cooled and then sent to the finishing mill. S4. The intermediate-rolled angle and channel steel is fed into the corresponding closed-end finishing roll pass and rolled through a 6-pass finishing mill. During the rolling process, the rolling speed and tension of each pass are controlled. The roll gap of each pass is controlled at 0.75-1.2mm, the rolling speed is 3.5-8m / s, and the tension is controlled at 12-18mm. After water cooling and shearing, the finished angle and channel steel is sent to the cooling bed after a delay of 700ms. S5. Control the temperature of the angle and channel steel on the cooling bed after finishing rolling. Cool the high-temperature finished steel uniformly and slowly on the cooling bed. Control the parameters of low-level dwell, middle-level dwell, high-level dwell, correction, LastBar delay and rising to the middle level on the cooling bed. Control the temperature of the upper cooling bed to 970-1030℃. Control the low-level dwell to 350-400ms, the middle-level dwell to 210-270ms, the high-level dwell to 1320-1420ms, the correction to 4500ms, the LastBar delay to 600ms, and the rising to the middle level to 220-300ms. The cooled angle and channel steel is then sent to the straightening machine. S6. The 10 rollers of the straightening machine are divided into three pre-straightening rollers at the entrance, four main straightening rollers in the middle, and three fine straightening rollers at the exit. The initial pressing amount of the main straightening rollers at the entrance is 15%-20% of the profile section thickness, the second roller 35%-40%, the third roller 20%, the fourth roller 15%-10%, and the fifth roller 5%. The deviation of pressing amount, straightening speed, and linear speed fluctuation at different parts of the same section are controlled during straightening. The deviation of pressing amount at different parts of the same section is controlled to be ≤0.2mm. The straightening speed is 18-35m / min, and the linear speed fluctuation is ≤±1m / min. A roller gap of 0.3-0.6mm is reserved. The straightened angle and channel steel is then fed into the cold saw. S7. The length range of cold-sawed angle channel steel is 6-12m. The speed of the sawing roller is adjusted according to different fixed lengths. When the fixed length is 6-8m, the sawing roller speed is 1.2-1.5m / s. When the fixed length is 9-12m, the sawing roller speed is 0.8-1m / s. The adjustment accuracy of the fixed length baffle is ±0.1mm. The response delay of the servo motor drive is ≤0.2s. The baffle reset error after each sawing does not exceed 0.05mm.

[0020] The implementation method of this embodiment is as follows: When rolling ∠6.3 angle steel, a 150mm*150mm steel billet is first heated in a heating furnace. During the heating process, the temperature of the heating section is 1050℃, the temperature of the soaking section is 1120℃, and the initial rolling temperature is 1100℃. Then, the steel billet is sequentially transported to the roughing mill, intermediate mill, and finishing mill through guide plates and transport rollers. The guide dimensions for the slitting rolling of ∠6.3 angle steel (K4 pass, Φ350 mill) are designed as follows: Inlet guide: K5 rolled piece width = 103mm, inlet guide opening = 108mm; K5 rolled piece apex angle height = 25mm, inlet guide height = 30mm; clearance with cutting hole = 0.5mm (aligned with center line).

[0021] Exit guide: K4 rolled piece width = 104mm, exit guide opening = 113mm; K4 rolled piece thickness = 20mm, exit guide opening = 30mm; exit guide shape = "butterfly"; clearance with butterfly hole = 0.3mm. The rolling program is shown in Table 1 below: Table 1 Rolling Procedure for ∠6.3 Angle Steel path size area elongation coefficient linear velocity motor speed Reduction ratio working roll diameter 1 95*175 16625 1.353 0.25 517 60.81 560 2 100*125 12250 1.357 0.34 554 48.024 560 3 68*146 8422 1.454 0.49 756 40 497 4 87*86 6305 1.306 0.64 695 28 494 5 56*118 5031 1.253 0.80 634 19.84 481 6 70*71 3752 1.341 1.08 662 15.149 472 7 40*105 3265 1.15 1.24 543 11.11 485 k7 85*40 3059 1.067 1.32 500 8.752 443 k6 10 2375 1.288 1.71 422 5 386 k5 7 1619 1.467 2.50 410 3.2 373 k4 7 1257 1.288 3.22 336 1.85 339 k3 7 1002 1.254 4.04 316 1.308 320 k2 6 800 1.253 5.06 291 1 331.84 k1 5 623 1.284 6.50 404 1 307.73 After water cooling and shearing, the precision-rolled angle and channel steel is fed into the cooling bed after a 700ms delay. The temperature of the angle and channel steel on the cooling bed is controlled at 1000℃. The high-temperature precision-rolled steel is uniformly and slowly cooled on the cooling bed. The cooling bed is controlled with a low-position dwell time of 400ms, a middle-position dwell time of 270ms, a high-position dwell time of 1420ms, a correction time of 4500ms, a LastBar delay of 600ms, and a rise to the middle position of 300ms. The cooled angle and channel steel is then sent to the straightening machine. The reduction of the main straightening roll at the entrance is initially distributed according to 18% of the section thickness, and the second roll... The straightening rollers are 37%, the third roller 20%, the fourth roller 12%, and the fifth roller 5%. The deviation of the amount of pressure at different parts of the same cross section is controlled to be ≤0.2mm. The straightening speed is 28m / min, the linear speed fluctuation is ≤±1m / min, and a 0.4mm gap between rollers is reserved. The straightened angle and channel steel is fed into the cold saw. When the fixed length of the angle and channel steel is 8m, the sawing roller speed is 1.3m / s. The adjustment accuracy of the fixed length baffle is ±0.1mm, the response delay of the servo motor drive is ≤0.2s, and the baffle reset error after each sawing does not exceed 0.05mm.

[0022] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A rolling mill for two-bar angle channel steel, characterized in that, The device includes a heating furnace (1) and a guide plate. The heating furnace (1) is a walking beam type heating furnace. The heating furnace (1) is connected to a roughing mill (2) through the guide plate. The maximum diameter of the rolls of the roughing mill (2) is set to φ640mm. The roughing mill (2) is connected to an intermediate mill (3) through the guide plate. The maximum diameter of the rolls of the intermediate mill (3) is set to φ540mm. The intermediate mill (3) is connected to a finishing mill (4) through the guide plate. The maximum diameter of the rolls of the finishing mill (4) is set to φ440mm. The finishing mill (4) is connected to a cooling bed (5) through the guide plate. The cooling bed (5) is connected to a straightener (6) through the guide plate. The straightener (6) is connected to a cold saw (7) through the guide plate.

2. A rolling process for two-bar angle channel steel, characterized in that, Includes the following steps: S1. The steel billet is heated in a heating furnace (1). During the heating process, the temperature of the heating section, the soaking section and the initial rolling section is controlled. After heating, the steel billet is transported to the roughing mill (2) through the guide plate and the conveying roller. S2. Select the corresponding angle and channel steel cutting hole type according to the product specifications of the angle and channel steel. Roll the steel billet with a size of 150mm*150mm into angle and channel steel through 6 passes of roughing mill (2) in sequence. Control the elongation coefficient, rolling force and rolling speed during the rolling process. After the rough rolled angle and channel steel is cut, it is transported to the intermediate mill (3). S3. The rough-rolled angle and channel steel is fed into the corresponding butterfly-shaped mill for intermediate rolling. It is rolled by four intermediate mills (3). During the rolling process, the roll gap, rolling speed and tension of each pass are controlled. The intermediate-rolled angle and channel steel is water-cooled and then transported to the finishing mill (4). S4. The angle and channel steel after intermediate rolling is fed into the corresponding closed-end finished product pass and rolled by a 6-pass finishing mill (4). During the rolling process, the rolling speed and tension of each pass are controlled. After the finished angle and channel steel is water-cooled and sheared, it is sent to the cooling bed (5) after a delay of 700ms. S5. Control the temperature of the angle and channel steel on the cooling bed (5) after finishing rolling. Cool the high-temperature finished steel uniformly and slowly on the cooling bed (5). Control the parameters of low position dwell, middle position dwell, high position dwell, correction, LastBar delay and rising to the middle position of the cooling bed (5). The cooled angle and channel steel is sent to the straightening machine (6). S6. Divide the 10 rollers of the straightening machine (6) into 3 rollers for pre-straightening at the entrance, 4 rollers for main straightening in the middle, and 3 rollers for fine straightening at the exit. The amount of pressure of the main roller at the entrance is initially distributed according to 15%-20% of the thickness of the profile section, 35%-40% for the second roller, 20% for the third roller, 15%-10% for the fourth roller, and 5% for the fifth roller. Control the deviation of the amount of pressure at different parts of the same section, the fluctuation of the straightening speed and the linear speed during straightening, and send the straightened angle and channel steel into the cold saw (7). S7. The length range of cold-sawed angle channel steel is 6-12m. The speed of the sawing roller is adjusted according to different fixed lengths. The adjustment accuracy of the fixed length baffle is ±0.1mm. The response delay of the servo motor drive is ≤0.2s. The baffle reset error after each sawing does not exceed 0.05mm.

3. The rolling process for two-bar angle channel steel according to claim 2, characterized in that, In step S1, the temperature of the heating section is controlled at 1000-1150℃, the temperature of the soaking section is controlled at 1030-1170℃, and the rolling temperature is controlled at 1070-1130℃.

4. The rolling process for two-bar angle channel steel according to claim 2, characterized in that, In step S2, the elongation coefficient for each pass is controlled between 1.31 and 1.

4. No rolling force adjustment is made for passes 1-8. Rolling force adjustment begins from pass 9. The formula for calculating the rolling force is as follows: Where P is the rolling force, μ is the friction coefficient of the steel roll, B is the width of the workpiece before rolling, R is the roll radius, Δh is the reduction, the roll gap of each pass is controlled at 125-170mm, and the rolling speed during roughing is controlled at 0.25-1m / s.

5. The rolling process for two-bar angle channel steel according to claim 2, characterized in that, In step S3, the roll gap for each pass is controlled at 10.5–27 mm, the rolling speed at 1.2–2.5 m / s, and the tension at 60–100 mm.

6. The rolling process for two-bar angle channel steel according to claim 2, characterized in that, In step S4, the roll gap for each pass is controlled at 0.75–1.2 mm, the rolling speed is 3.5–8 m / s, and the tension is controlled at 12–18 mm.

7. The rolling process for two-bar angle channel steel according to claim 2, characterized in that, In step S5, the temperature of the upper cooling bed (5) is controlled at 970-1030℃, the low position dwell time is controlled at 350-400ms, the middle position dwell time is controlled at 210-270ms, the high position dwell time is controlled at 1320-1420ms, the correction time is controlled at 4500ms, the LastBar delay time is controlled at 600ms, and the rise to the middle position time is controlled at 220-300ms.

8. The rolling process for two-bar angle channel steel according to claim 2, characterized in that, In step S6, the deviation of the amount of pressure applied at different parts of the same cross section is controlled to be ≤0.2mm, the straightening speed is 18-35m / min, the linear speed fluctuation is ≤±1m / min, and a gap of 0.3-0.6mm between the rollers is reserved.

9. The rolling process for two-bar angle channel steel according to claim 2, characterized in that, In step S7, when the fixed length is 6-8m, the sawing roller speed is 1.2-1.5m / s, and when the fixed length is 9-12m, the sawing roller speed is 0.8-1m / s.

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