Material type control method for improving negative error rate of triple-cutting deformed steel bar

Abstract

The invention discloses a material type control method for improving the negative error rate of triple-cutting threaded steel. A clamping and conveying device is additionally arranged between the 2 # shear and the rolling mill, so that a rolled piece horizontally enters the rolling mill, torsion is reduced, and stability is improved; the hole pattern is optimized, it is ensured that a center line segmentation hole is larger than a side line segmentation hole, and the ratio of the center line segmentation hole to the side line segmentation hole is 1: 1.25; optimization work is carried out for a finished product and a sortie roller cooling water pipe before the finished product, an intelligent cooling control system is adopted, and the flow, pressure and temperature of side line and middle line cooling water pipes are monitored in real time and accurately controlled. Wherein the side line cooling water pipe adopts a 1.5-inch water inlet pipe and is provided with a variable frequency water pump, the maximum flow can reach 50m / h, and the system is further provided with a standby power supply, so that cooling control can be maintained for 30 minutes during power failure; in the rolling process, once the weight difference between the center line and the side line is large, the K5 material type is adjusted in time, and it is guaranteed that the center line slitting hole is full.

Description

Technical Field

[0001] The invention relates to the technical field of negative difference rate of three-cut threaded steel, and specifically to a material shape control method for improving the negative difference rate of three-cut threaded steel. Background Art

[0002] In the field of rebar rolling, the three-cut rolling process can significantly improve production efficiency compared to single-line rolling, but it faces great challenges in controlling the negative difference rate. During three-cut rolling, the three steels before cutting are connected to each other. The center line steel is constrained by the steel on both sides and lacks space for expansion, resulting in a relatively low height of the longitudinal reinforcement; while the side line steel can be freely expanded outward, and the longitudinal reinforcement is higher. This structural difference causes the weight of the two side line steels to be significantly greater than that of the center line steel, making the three-line negative difference of the finished product extremely unstable, often showing a high center line negative difference rate and a low side line negative difference rate. When the bundle weight meets the required negative difference rate, the center line negative difference rate frequently exceeds the range specified by the national standard [specific national standard number and clause], seriously affecting product quality. In actual use, it may lead to safety hazards such as reduced bearing capacity of building structures.

[0003] From the rolling process, after the rectangular rolled pieces produced by the intermediate rolling mill pass through the 2# shear, the mill head cutting operation easily causes the rolled pieces to twist due to the large distance between the 2# shear and the next mill, making it difficult to enter the mill in the center, which in turn causes the weight deviation of the two side line steels. In addition, in the splitting frame, the side line steel has a large heat dissipation area and a fast heat dissipation speed, while the center line steel dissipates heat relatively slowly. According to actual production monitoring data, the temperature of the side line after splitting is 20°C lower than that of the center line. In the subsequent rolling process, this temperature difference causes the side line hole type wear of the finished product and the front frame of the finished product (the two frames after splitting) to increase, and the weight growth rate of the side line finished product is much faster than that of the center line, further worsening the weight difference problem between the side line and the center line.

[0004] In order to solve the above problems, a material shape control method for improving the negative difference rate of three-cut rebar is proposed. Summary of the invention

[0005] The purpose of the present invention is to solve the above-mentioned problem and provide a material shape control method for improving the negative difference rate of three-cut threaded steel.

[0006] The specific scheme of the present invention is: a material shape control method for improving the negative difference rate of three-cut threaded steel, comprising the following steps: S1. Improve the stability of rolled pieces: add a clamping device between the 2# shear and the rolling mill, which is used to enable the rolled pieces to enter the rolling mill in a horizontal state, reduce torsion, and improve the stability of the rolled pieces; S2. Hole type optimization: adjust the size of the sideline cutting hole and the centerline cutting hole to ensure that the centerline cutting hole is larger than the sideline cutting hole; S3. Optimization of cooling water pipes for finished products and pre-finished product rolls: side cooling water pipes use 1.5-inch water inlet pipes; center cooling water pipes use 1.2-inch water inlet pipes; S4. Material shape control during rolling: When there is a large weight difference between the center line and the side line, adjust the material shape in time to ensure that the center line cutting hole is full.

[0007] Further, in step S1, the clamping device comprises: a shell, a conveying channel is provided inside the shell, a bell mouth is provided at one end of the conveying channel, and a roller mechanism is provided at the other end of the conveying channel, and the roller mechanism comprises: Upper connecting arms, two of which are arranged on both sides of the shell at the upper part of the shell, and are rotatably connected to the shell, and an upper roller rotatably connected to the upper connecting arms is arranged between the two upper connecting arms; Lower connecting arms, two of which are arranged on both sides of the shell at the lower part of the shell, and are rotatably connected to the shell, and a lower roller rotatably connected to the shell is arranged between the two lower connecting arms; A tension spring, wherein the upper end of the tension spring is connected to the middle part of the upper connecting arm, and the lower end of the tension spring is connected to the middle part of the lower connecting arm.

[0008] Furthermore, in step S2, the ratio of the sideline cutting holes to the centerline cutting holes is adjusted to 1:1.25.

[0009] Furthermore, in step S4, when the weight difference between the center line and the side line is large, the K5 material type is adjusted in time to ensure that the center line cutting hole is filled.

[0010] Furthermore, in step S3, an intelligent cooling control system is used to monitor and accurately control the flow, pressure and temperature of the side and center cooling water pipes in real time; the side cooling water pipes use 1.5-inch water inlet pipes and are equipped with variable frequency water pumps, which can automatically adjust the water flow according to the rolling speed and the temperature of the rolled piece, with a maximum flow of 50m³ / h.

[0011] Furthermore, in step S3, the intelligent cooling control system is equipped with a backup power supply to ensure that cooling control can be maintained for at least 30 minutes in the event of a sudden power outage.

[0012] The present invention has the following beneficial effects: 1. Stabilize the negative difference rate and improve product quality: Through the control method of the present invention, the hole type is accurately optimized to ensure that the center line cutting hole is larger than the side line cutting hole, effectively improve the problem of low longitudinal reinforcement height caused by lack of wide expansion space in the center line steel, balance the weight difference between the center line and side line steel, and make the three-line negative difference of the finished product tend to be stable; significantly improve product quality.

[0013] 2. Improve the stability of rolled pieces and reduce weight deviation: Adding a clamping device between the 2# shear and the rolling mill can enable the rolled pieces to enter the rolling mill in a horizontal state, effectively reducing the torsion phenomenon caused by the mill head cutting; this ensures that the rolled pieces can enter the rolling mill in the center, avoiding the weight deviation of the two side line steels caused by torsion, and further improving the consistency of product quality.

[0014] 3. Optimize the cooling system and balance the temperature difference: Adopt intelligent cooling control system to monitor and accurately control the flow, pressure and temperature of the side and center cooling water pipes in real time; the side cooling water pipes are equipped with variable frequency water pumps, which can automatically adjust the water flow according to the rolling speed and the temperature of the rolled piece, with a maximum flow of 50m³ / h. This effectively alleviates the problem of fast heat dissipation of side steel and slow heat dissipation of center steel in the cutting frame, reduces the aggravation of the side hole type wear of the finished product and the front frame of the finished product caused by temperature difference, and thus narrows the difference in the weight growth rate of the side and center finished products, making the weight of the three lines more balanced.

[0015] 4. Enhance process reliability and reduce quality risks: The intelligent cooling control system is equipped with a backup power supply. In the event of a sudden power outage, it can still maintain cooling control for at least 30 minutes, ensuring the continuity and stability of the rolling process, avoiding process interruptions and quality problems caused by power outages, and enhancing the reliability of the entire three-cut rebar rolling process and reducing quality risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the clamping and conveying device in the present invention; Figure 2 Schematic diagram of the connection relationship between the sideline cutting hole and the centerline cutting hole in the present invention; In the figure: 1. Shell; 101. Conveying channel; 102. Bell mouth; 2. Roller mechanism; 201. Upper connecting arm; 202. Lower connecting arm; 203. Upper roller; 204. Lower roller; 205. Tension spring; 3. Side line cutting hole; 4. Center line cutting hole. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0019] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0020] Please refer to Figure 1-Figure 2 A material shape control method for improving the negative difference rate of three-cut thread steel comprises the following steps: S1. Improve the stability of rolled pieces: add a clamping device between the 2# shear and the rolling mill, which is used to enable the rolled pieces to enter the rolling mill in a horizontal state, reduce torsion, and improve the stability of the rolled pieces; S2. Hole type optimization: adjust the size of the side cutting hole 3 and the center cutting hole 4 to ensure that the center cutting hole 4 is larger than the side cutting hole 3, and the ratio of the side cutting hole 3 to the center cutting hole 4 is 1:1.25; S3. Optimization of cooling water pipes for finished products and pre-finished product rolls: side cooling water pipes use 1.5-inch water inlet pipes; center cooling water pipes use 1.2-inch water inlet pipes; S4. Material type control during rolling: When there is a large weight difference between the center line and the side line, adjust the material type in time to ensure that the center line cutting hole 4 is full.

[0021] In this embodiment, in step S1, the clamping device includes: a housing 1, a conveying channel 101 is provided inside the housing 1, a bell mouth 102 is provided at one end of the conveying channel 101, and a roller mechanism 2 is provided at the other end of the conveying channel 101, and the roller mechanism 2 includes: An upper connecting arm 201, two of which are arranged on both sides of the shell 1 at the upper part of the shell 1, and are rotatably connected to the shell 1, and an upper roller 203 rotatably connected thereto is arranged between the two upper connecting arms 201; Lower connecting arms 202, two of which are arranged at both sides of the shell 1 at the lower part of the shell 1, and are rotatably connected to the shell 1, and a lower roller 204 rotatably connected thereto is arranged between the two lower connecting arms 202; The tension spring 205 has an upper end connected to the middle of the upper connecting arm 201 , and a lower end connected to the middle of the lower connecting arm 202 .

[0022] In this embodiment, in step S4, when the weight difference between the center line and the side line is large, the K5 material type is adjusted in time to ensure that the center line cutting hole 4 is filled.

[0023] In this embodiment, in step S3, an intelligent cooling control system is used to monitor and accurately control the flow, pressure and temperature of the side and center cooling water pipes in real time. The side cooling water pipe uses a 1.5-inch water inlet pipe and is equipped with a variable frequency water pump, which can automatically adjust the water flow according to the rolling speed and the temperature of the rolled piece, and the maximum flow can reach 50m³ / h.

[0024] In this embodiment, in step S3, the intelligent cooling control system is equipped with a backup power supply to ensure that cooling control can be maintained for at least 30 minutes in the event of a sudden power outage.

[0025] The present invention has the following beneficial effects: 1. Stabilize the negative difference rate and improve product quality: Through the control method of the present invention, the hole type is accurately optimized to ensure that the center line cutting hole 4 is larger than the side line cutting hole 3, effectively improving the problem of low longitudinal reinforcement height caused by lack of wide expansion space in the center line steel, balancing the weight difference between the center line and side line steel, and making the three-line negative difference of the finished product tend to be stable; significantly improving product quality.

[0026] 2. Improve the stability of rolled pieces and reduce weight deviation: Adding a clamping device between the 2# shear and the rolling mill can enable the rolled pieces to enter the rolling mill in a horizontal state, effectively reducing the torsion phenomenon caused by the mill head cutting; this ensures that the rolled pieces can enter the rolling mill in the center, avoiding the weight deviation of the two side line steels caused by torsion, and further improving the consistency of product quality.

[0027] 3. Optimize the cooling system and balance the temperature difference: Adopt intelligent cooling control system to monitor and accurately control the flow, pressure and temperature of the side and center cooling water pipes in real time; the side cooling water pipes are equipped with variable frequency water pumps, which can automatically adjust the water flow according to the rolling speed and the temperature of the rolled piece, with a maximum flow of 50m³ / h. This effectively alleviates the problem of fast heat dissipation of side steel and slow heat dissipation of center steel in the cutting frame, reduces the aggravation of the side hole type wear of the finished product and the front frame of the finished product caused by temperature difference, and thus narrows the difference in the weight growth rate of the side and center finished products, making the weight of the three lines more balanced.

[0028] 4. Enhance process reliability and reduce quality risks: The intelligent cooling control system is equipped with a backup power supply. In the event of a sudden power outage, it can still maintain cooling control for at least 30 minutes, ensuring the continuity and stability of the rolling process, avoiding process interruptions and quality problems caused by power outages, and enhancing the reliability of the entire three-cut rebar rolling process and reducing quality risks.

Claims

1. A material shape control method for improving the negative difference rate of three-cut threaded steel, characterized by: The following steps are involved: S1. Improve the stability of rolled pieces: add a clamping device between the 2# shear and the rolling mill, which is used to enable the rolled pieces to enter the rolling mill in a horizontal state, reduce torsion, and improve the stability of the rolled pieces; S2. Hole type optimization: adjust the size of the sideline cutting hole and the centerline cutting hole to ensure that the centerline cutting hole is larger than the sideline cutting hole; S3. Optimization of cooling water pipes for finished products and pre-finished product rolls: side cooling water pipes use 1.5-inch water inlet pipes; center cooling water pipes use 1.2-inch water inlet pipes; S4. Material shape control during rolling: When there is a large weight difference between the center line and the side line, adjust the material shape in time to ensure that the center line cutting hole is full.

2. A material shape control method for improving the negative difference rate of three-cut threaded steel according to claim 1, characterized in that: In step S1, the clamping device comprises: a shell, a conveying channel is provided inside the shell, a bell mouth is provided at one end of the conveying channel, and a roller mechanism is provided at the other end of the conveying channel, and the roller mechanism comprises: Upper connecting arms, two of which are arranged on both sides of the shell at the upper part of the shell, and are rotatably connected to the shell, and an upper roller rotatably connected to the upper connecting arms is arranged between the two upper connecting arms; Lower connecting arms, two of which are arranged on both sides of the shell at the lower part of the shell, and are rotatably connected to the shell, and a lower roller rotatably connected to the shell is arranged between the two lower connecting arms; A tension spring, wherein the upper end of the tension spring is connected to the middle part of the upper connecting arm, and the lower end of the tension spring is connected to the middle part of the lower connecting arm.

3. A material shape control method for improving the negative difference rate of three-cut threaded steel according to claim 1, characterized in that: In step S2, the ratio of the sideline cutting holes to the centerline cutting holes is adjusted to 1:1.

25.

4. A material shape control method for improving the negative difference rate of three-cut threaded steel according to claim 1, characterized in that: In step S4, when the weight difference between the center line and the side line is large, the K5 material type is adjusted in time to ensure that the center line cutting hole is filled.

5. The material shape control method for improving the negative difference rate of three-cut threaded steel according to claim 1 is characterized in that: In step S3, an intelligent cooling control system is used to monitor and accurately control the flow, pressure and temperature of the side and center cooling water pipes in real time; the side cooling water pipes use 1.5-inch water inlet pipes and are equipped with variable frequency water pumps, which can automatically adjust the water flow according to the rolling speed and rolled piece temperature, with a maximum flow of 50m³ / h.

6. A material shape control method for improving the negative difference rate of three-cut threaded steel according to claim 5, characterized in that: In step S3, the intelligent cooling control system is equipped with a backup power supply to ensure that cooling control can be maintained for at least 30 minutes in the event of a sudden power outage.

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