A material shape control method for improving the negative difference rate of three-cut rebar

Abstract

This invention discloses a material shape control method to improve the negative difference rate of three-section rebar. By adding a clamping device between the No. 2 shear and the rolling mill, the rolled piece enters the mill horizontally, thereby reducing torsion and improving stability. The roll pass is optimized to ensure that the center line cutting hole is larger than the edge line cutting hole, with a ratio of 1:1.25. Optimization is carried out on the cooling water pipes of the finished product and the rolls before the finished product, using an intelligent cooling control system to monitor and precisely control the flow rate, pressure, and temperature of the edge and center line cooling water pipes in real time. The edge line cooling water pipe uses a 1.5-inch inlet pipe and is equipped with a variable frequency water pump with a maximum flow rate of 50 m³ / h. The system is also equipped with a backup power supply to maintain cooling control for 30 minutes during power outages. During the rolling process, if the weight difference between the center line and the edge line exceeds a threshold, the K5 material shape is adjusted in time to ensure that the center line cutting hole is filled.

Description

Technical Field

[0001] This invention relates to the field of negative differential rate technology for three-section threaded steel, specifically a material shape control method for improving the negative differential rate of three-section threaded steel. Background Technology

[0002] In the field of rebar rolling, while the three-slit rolling process significantly improves production efficiency compared to single-line rolling, it faces significant challenges in controlling the negative deviation rate. In three-slit rolling, the three steel bars before slit are interconnected. The center steel bar, constrained by the two side steel bars, lacks sufficient space to expand, resulting in relatively low longitudinal rib height. In contrast, the edge steel bars can expand freely outwards, resulting in higher longitudinal ribs. This structural difference leads to the two edge steel bars being significantly heavier than the center steel bar, causing highly unstable negative deviation rates in the finished product, often exhibiting a high negative deviation rate in the center and a low negative deviation rate in the edge steel bars. When the bundle weight meets the required negative deviation rate, the center negative deviation rate frequently exceeds the national standard range, seriously affecting product quality and potentially leading to safety hazards such as reduced structural load-bearing capacity in actual use.

[0003] From the rolling process perspective, after the rectangular rolled pieces produced by the intermediate rolling mill pass through the No. 2 shear, the distance between the No. 2 shear and the next rolling mill exceeds the threshold. This causes the mill head-cutting operation to easily induce twisting of the rolled pieces, making it difficult for them to be centered and enter the mill, resulting in a weight deviation between the two edge sections. Furthermore, in the slitting stand, the edge section steel dissipates heat quickly due to its larger heat dissipation area, while the center section steel dissipates heat relatively slowly. Actual production monitoring data shows that the edge section temperature is 20°C lower than the center section temperature after slitting. During subsequent rolling processes, this temperature difference exacerbates the wear of the edge section pass profiles in the finished product and the two stands before the finished product (the two stands after slitting). The weight increase rate of the edge section finished product far exceeds that of the center section, further worsening the weight difference problem between the edge and center sections.

[0004] To address the aforementioned issues, a material shape control method for improving the negative deviation rate of triple-cut rebar is proposed. Summary of the Invention

[0005] The purpose of this invention is to solve the above-mentioned problems and provide a material shape control method to improve the negative difference rate of three-cut rebar.

[0006] The specific solution of this invention is: a material shape control method for improving the negative deviation rate of three-section rebar, comprising the following steps:

[0007] S1. Improve the stability of the rolled piece: A clamping device is added between the No. 2 shear and the rolling mill. The clamping device is used to enable the rolled piece to enter the rolling mill in a horizontal state, reduce torsion, and improve the stability of the rolled piece.

[0008] S2. Hole type optimization: Adjust the size of the edge cutting hole and the center cutting hole to ensure that the center cutting hole is larger than the edge cutting hole;

[0009] S3. Optimization of cooling water pipes for finished products and pre-finishing rolls: Use 1.5-inch inlet pipes for edge cooling water pipes; use 1.2-inch inlet pipes for center cooling water pipes;

[0010] S4. Material shape control during rolling: When the weight difference between the center line and the edge line exceeds the threshold, adjust the material shape stand in time to ensure that the center line cutting hole is filled.

[0011] Furthermore, in step S1, the clamping device includes: a housing, the housing having a conveying channel inside, one end of the conveying channel having a flared opening, and the other end of the conveying channel having a roller mechanism, the roller mechanism including:

[0012] The upper connecting arms are located on both sides of the upper part of the housing and are rotatably connected to the housing. An upper roller is provided between the two upper connecting arms and is rotatably connected to it.

[0013] The lower connecting arms are located on both sides of the lower part of the housing and are rotatably connected to the housing. A lower roller is provided between the two lower connecting arms and is rotatably connected to it.

[0014] A tension spring, the upper end of which is connected to the middle of the upper connecting arm, and the lower end of which is connected to the middle of the lower connecting arm.

[0015] Furthermore, in step S2, the ratio of the edge cutting hole to the center cutting hole is adjusted to 1:1.25.

[0016] Furthermore, in step S4, when the weight difference between the center line and the edge line exceeds the threshold, the K5 material shape is adjusted in time to ensure that the center line cutting hole is filled.

[0017] Furthermore, in step S3, an intelligent cooling control system is adopted to monitor and precisely control the flow rate, pressure, and temperature of the edge and center cooling water pipes in real time. The edge cooling water pipes use 1.5-inch inlet pipes and are equipped with variable frequency water pumps, which can automatically adjust the water flow rate according to the rolling speed and workpiece temperature, with a maximum flow rate of 50 m³ / h.

[0018] Furthermore, in step S3, the intelligent cooling control system is equipped with a backup power supply to ensure that cooling control can still be maintained for at least 30 minutes in the event of a sudden power outage.

[0019] The present invention has the following beneficial effects:

[0020] 1. Stabilize negative tolerance rate and improve product quality: Through the control method of this invention, the hole shape is precisely optimized to ensure that the center line cutting hole is larger than the edge line cutting hole, which effectively improves the problem of low longitudinal rib height caused by the lack of wide space in the center line steel, balances the weight difference between the center line and the edge line steel, and makes the negative tolerance of the three lines of the finished product tend to be stable; significantly improving product quality.

[0021] 2. Improve the stability of rolled pieces and reduce weight deviation: The addition of a clamping device between the No. 2 shear and the rolling mill enables the rolled pieces to enter the rolling mill in a horizontal state, effectively reducing the torsion phenomenon generated after the rolling mill head is cut off. This ensures that the rolled pieces can enter the rolling mill in a centered position, avoiding weight deviation of the steel on the two sides due to torsion, and further improving the consistency of product quality.

[0022] 3. Optimized cooling system to balance temperature differences: An intelligent cooling control system is adopted to monitor and precisely control the flow rate, pressure, and temperature of the cooling water pipes in the edge and center lines in real time. The edge cooling water pipes are equipped with variable frequency water pumps, which can automatically adjust the water flow rate according to the rolling speed and workpiece temperature, with a maximum flow rate of 50 m³ / h. This effectively alleviates the problem of faster heat dissipation of edge steel and slower heat dissipation of center steel in the cutting stand, reduces the increased wear of the finished product and the edge strip in the previous stand caused by temperature differences, and thus narrows the gap in the weight increase rate of the finished product between the edge and center lines, making the weight of the three lines more balanced.

[0023] 4. Enhanced process reliability and reduced quality risks: The intelligent cooling control system is equipped with a backup power supply, which can maintain cooling control for at least 30 minutes in the event of a sudden power outage. This ensures the continuity and stability of the rolling process, avoids process interruptions and quality problems caused by power outages, enhances the reliability of the entire three-cut threaded steel rolling process, and reduces quality risks. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the clamping device in the present invention;

[0025] Figure 2 This is a schematic diagram showing the connection relationship between the edge cutting hole and the center cutting hole in this invention;

[0026] In the diagram: 1. Housing; 101. Conveying channel; 102. Trumpet mouth; 2. Roller mechanism; 201. Upper connecting arm; 202. Lower connecting arm; 203. Upper roller; 204. Lower roller; 205. Tension spring; 3. Edge cutting hole; 4. Center cutting hole. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0029] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0030] Please refer to Figures 1-2 A material profile control method for improving the negative deviation rate of three-section rebar includes the following steps:

[0031] S1. Improve the stability of the rolled piece: A clamping device is added between the No. 2 shear and the rolling mill. The clamping device is used to enable the rolled piece to enter the rolling mill in a horizontal state, reduce torsion, and improve the stability of the rolled piece.

[0032] S2. Hole type optimization: Adjust the size of the edge line dividing hole 3 and the center line dividing hole 4 to ensure that the center line dividing hole 4 is larger than the edge line dividing hole 3, and the ratio of the edge line dividing hole 3 to the center line dividing hole 4 is 1:1.25.

[0033] S3. Optimization of cooling water pipes for finished products and pre-finishing rolls: Use 1.5-inch inlet pipes for edge cooling water pipes; use 1.2-inch inlet pipes for center cooling water pipes;

[0034] S4. Material shape control during rolling: When the weight difference between the center line and the edge line exceeds the threshold, adjust the material shape stand in time to ensure that the center line cutting hole 4 is filled.

[0035] In this embodiment, in step S1, the clamping device includes: a housing 1, the housing 1 having a conveying channel 101 inside, one end of the conveying channel 101 having a flared opening 102, and the other end of the conveying channel 101 having a roller mechanism 2, the roller mechanism 2 including:

[0036] Upper connecting arm 201, two upper connecting arms are provided on both sides of the upper part of the housing 1 and are rotatably connected to the housing 1, and an upper roller 203 is provided between the two upper connecting arms 201 and rotatably connected thereto;

[0037] The lower connecting arm 202 is provided on both sides of the housing 1 at the lower part of the housing 1 and is rotatably connected to the housing 1. A lower roller 204 is provided between the two lower connecting arms 202 and is rotatably connected to them.

[0038] A tension spring 205 is provided, with its upper end connected to the middle of the upper connecting arm 201 and its lower end connected to the middle of the lower connecting arm 202.

[0039] In this embodiment, in step S4, when the weight difference between the center line and the edge line exceeds the threshold, the K5 material type is adjusted in time to ensure that the center line cutting hole 4 is filled.

[0040] In this embodiment, in step S3, an intelligent cooling control system is used to monitor and precisely control the flow rate, pressure, and temperature of the edge and center cooling water pipes in real time. The edge cooling water pipes use 1.5-inch inlet pipes and are equipped with variable frequency water pumps, which can automatically adjust the water flow rate according to the rolling speed and workpiece temperature, with a maximum flow rate of 50 m³ / h.

[0041] In this embodiment, in step S3, the intelligent cooling control system is equipped with a backup power supply to ensure that cooling control can still be maintained for at least 30 minutes in the event of a sudden power outage.

[0042] The present invention has the following beneficial effects:

[0043] 1. Stabilize negative tolerance rate and improve product quality: Through the control method of this invention, the hole shape is precisely optimized to ensure that the center line cutting hole 4 is larger than the edge line cutting hole 3, which effectively improves the problem of low longitudinal rib height caused by the lack of wide space in the center line steel, balances the weight difference between the center line and the edge line steel, and makes the negative tolerance of the three lines of the finished product tend to be stable; significantly improving product quality.

[0044] 2. Improve the stability of rolled pieces and reduce weight deviation: The addition of a clamping device between the No. 2 shear and the rolling mill enables the rolled pieces to enter the rolling mill in a horizontal state, effectively reducing the torsion phenomenon generated after the rolling mill head is cut off. This ensures that the rolled pieces can enter the rolling mill in a centered position, avoiding weight deviation of the steel on the two sides due to torsion, and further improving the consistency of product quality.

[0045] 3. Optimized cooling system to balance temperature differences: An intelligent cooling control system is adopted to monitor and precisely control the flow rate, pressure, and temperature of the cooling water pipes in the edge and center lines in real time. The edge cooling water pipes are equipped with variable frequency water pumps, which can automatically adjust the water flow rate according to the rolling speed and workpiece temperature, with a maximum flow rate of 50 m³ / h. This effectively alleviates the problem of faster heat dissipation of edge steel and slower heat dissipation of center steel in the cutting stand, reduces the increased wear of the finished product and the edge strip in the previous stand caused by temperature differences, and thus narrows the gap in the weight increase rate of the finished product between the edge and center lines, making the weight of the three lines more balanced.

[0046] 4. Enhanced process reliability and reduced quality risks: The intelligent cooling control system is equipped with a backup power supply, which can maintain cooling control for at least 30 minutes in the event of a sudden power outage. This ensures the continuity and stability of the rolling process, avoids process interruptions and quality problems caused by power outages, enhances the reliability of the entire three-cut threaded steel rolling process, and reduces quality risks.

Claims

1. A material shape control method for improving the negative deviation rate of three-section rebar, characterized in that: Includes the following steps: S1. Improve the stability of the rolled piece: A clamping device is added between the No. 2 shear and the rolling mill. The clamping device is used to enable the rolled piece to enter the rolling mill in a horizontal state, reduce torsion, and improve the stability of the rolled piece. S2. Hole type optimization: Adjust the size of the edge cutting hole and the center cutting hole to ensure that the center cutting hole is larger than the edge cutting hole, and adjust the ratio of the edge cutting hole to the center cutting hole to 1:1.25; S3. Optimization of cooling water pipes for finished products and pre-finishing rolls: Use 1.5-inch inlet pipes for edge cooling water pipes; use 1.2-inch inlet pipes for center cooling water pipes; S4. Material shape control during rolling: When the weight difference between the center line and the edge line exceeds the threshold, adjust the material shape stand in time to ensure that the center line cutting hole is filled.

2. The material shape control method for improving the negative deviation rate of three-section rebar according to claim 1, characterized in that: in In step S1, the clamping device includes: a housing, the housing having a conveying channel inside, one end of the conveying channel having a flared opening, and the other end of the conveying channel having a roller mechanism, the roller mechanism including: The upper connecting arms are located on both sides of the upper part of the housing and are rotatably connected to the housing. An upper roller is provided between the two upper connecting arms and is rotatably connected to it. The lower connecting arms are located on both sides of the lower part of the housing and are rotatably connected to the housing. A lower roller is provided between the two lower connecting arms and is rotatably connected to it. A tension spring, the upper end of which is connected to the middle of the upper connecting arm, and the lower end of which is connected to the middle of the lower connecting arm.

3. The material shape control method for improving the negative difference rate of three-section rebar according to claim 1, characterized in that: in In step S4, when the weight difference between the center line and the edge line exceeds the threshold, the K5 material type is adjusted in time to ensure that the center line cutting hole is filled.

4. A material profile control method for improving the negative deviation rate of three-section rebar according to claim 1, characterized in that: in In step S3, an intelligent cooling control system is used to monitor and precisely control the flow rate, pressure, and temperature of the edge and center cooling water pipes in real time. The edge cooling water pipes use 1.5-inch inlet pipes and are equipped with variable frequency water pumps, which can automatically adjust the water flow rate according to the rolling speed and workpiece temperature, with a maximum flow rate of 50 m³ / h.

5. A material profile control method for improving the negative deviation rate of three-section rebar according to claim 4, characterized in that: in In step S3, the intelligent cooling control system is equipped with a backup power supply to ensure that cooling control can still be maintained for at least 30 minutes in the event of a sudden power outage.

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