Constant-weight billet supply method in continuous casting small square billet direct rolling mode

Abstract

The invention relates to a fixed-weight billet supply method in a continuous casting small square billet direct rolling mode, and belongs to the technical field of metallurgical methods. According to the technical scheme, a fixed-weight weighing device is installed between the rear portion of a flame cutting machine / hydraulic shear and a blank moving vehicle, and the weight of each casting blank is weighed in real time; the weighing period of each flow casting blank is set; casting blank weighing precision is set, and casting blanks of all flows are weighed independently; and the weight of the next casting blank is adjusted according to the length of the non-sizing material after rolling of each casting blank. The method has the beneficial effects that by finely controlling the weight of each continuous casting billet, non-fixed-length materials of straight steel bars / coiled screws are reduced, production is smooth, the problem that the non-fixed-length materials are too large due to different weights of the continuous casting billets is solved, the yield of the casting billets is increased, the non-fixed-length materials generated during rolling are reduced, and the production cost is reduced. Wide popularization and application prospects are realized.

Description

Technical Field

[0001] The present invention relates to a method for supplying billets with a fixed weight in the direct rolling mode of continuous casting small square billets, belonging to the technical field of metallurgical methods. Background Art

[0002] At present, most of the newly built straight bar thread and spiral bar production lines in China adopt the direct rolling process of continuous casting small square billets. After the continuous casting billets are produced at high speed, they do not enter the heating furnace, but are directly rolled using the waste heat of the high-speed continuous casting billets. The characteristics of this process are fast rolling speed, high efficiency, and reduced use of heating furnace gas. However, the waste heat of high-speed continuous casting is very large, and its thermal contraction coefficient is also very high. During production, its length is relatively difficult to control. At the end of the process, compared with the traditional heating furnace rolling process, there are often many non-standard-length materials after direct rolling.

[0003] The adoption of the technology of supplying billets with a fixed weight can effectively alleviate this problem. It takes a certain amount of time to weigh the casting billets, while the direct rolling production requires reducing the waiting time of the casting billets. Therefore, how to balance the weighing time and waiting time of the casting billets has become the key to the success or failure of supplying billets with a fixed weight in the direct rolling model. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for supplying billets with a fixed weight in the direct rolling mode of continuous casting small square billets. By precisely controlling the weight of each continuous casting billet, the non-standard-length materials of straight bar steel bars / spiral bars are reduced, the production runs smoothly, and the situation of excessive non-standard-length materials caused by different weights of continuous casting billets is solved. It not only improves the billet yield rate but also reduces the non-standard-length materials generated during rolling, has a wide application prospect, and effectively solves the above problems existing in the background art.

[0005] The technical solution of the present invention is: a method for supplying billets with a fixed weight in the direct rolling mode of continuous casting small square billets, comprising the following steps: (1) Install a fixed-weight weighing device between the flame cutting machine / hydraulic shear and the billet transfer car to weigh the weight of each casting billet in real time; (2) Set the weighing cycle of the casting billets for each strand; (3) Set the weighing accuracy of the casting billets, and weigh each strand of casting billets separately; (4) After the casting billet is weighed, send it to the fixed-length control system for cutting; (5) Adjust the weight of the next casting billet according to the length of the non-standard-length material after rolling of each casting billet.

[0006] The cross-section of the square billet continuous casting machine is 150mm×150mm to 180mm×180mm, the arc radius of the casting billet is 9-12m, the drawing speed of the continuous casting machine under normal production is 3.5-4.5m / min, and the fixed length of the weighed casting billet is 10-12 meters.

[0007] In step (2), the weighing cycle for a single billet is 9 - 13 seconds, and the waiting time for a single billet is less than 60 seconds.

[0008] In step (3), the weighing accuracy of the billet is the target weight ±5 kg; except for special cases, each direct-rolling billet is weighed, and the billet weighing rate is greater than 98%.

[0009] The special cases include starting casting or stopping casting.

[0010] The beneficial effects of the present invention are as follows: By precisely controlling the weight of each continuous casting billet, the non-standard-length materials of straight bars / coiled bars are reduced, enabling smooth production, solving the problem of excessive differences in non-standard-length materials caused by different billet weights, not only improving the billet yield rate but also reducing the non-standard-length materials generated during rolling, and having a wide application prospect for popularization. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a schematic structural diagram of the present invention; In the figure: multi-strand small billet continuous caster 1, fixed-length control system 2, weighing computer 3, PLC 4, fixed-weight weighing device 5, billet one 6, billet two 7, billet three 8, fixed-length shearing process 9, fixed-length tracking process 10, direct rolling process 11, billet pulling direction 12. DETAILED DESCRIPTION OF THE INVENTION

[0012] In order to make the objectives, technical solutions, and advantages of the invention implementation cases clearer, the technical solutions in the invention implementation cases will be clearly and completely described below in conjunction with the accompanying drawings in the implementation cases. Obviously, the described implementation cases are a small part of the implementation cases of the present invention, rather than all of them. Based on the implementation cases of the present invention, all other implementation cases obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0013] A method for supplying billets with fixed weight in a continuous casting small billet direct rolling mode includes the following steps: (1) Install a fixed-weight weighing device between the flame cutting machine / hydraulic shear and the billet transfer car to weigh the weight of each billet in real time; (2) Set the weighing cycle for each strand of billets; (3) Set the weighing accuracy of the billets, and weigh each strand of billets separately; (4) After the billet is weighed, it is sent to the fixed-length control system for cutting; (5) Adjust the weight of the next billet according to the length of the non-standard-length material after rolling each billet.

[0014] The cross-section of the billet continuous casting machine is 150mm×150mm to 180mm×180mm, the arc radius of the cast billet is 9 - 12m. When continuously casting small billets for direct rolling into straight bars or coil bars, the drawing speed range is 3.5 - 4.5m / min, and the specified length of the weighed cast billet is 10 - 12 meters.

[0015] In the said step (2), the weighing cycle for a single cast billet is 9 - 13 seconds, and the waiting time for a single cast billet is less than 60 seconds.

[0016] In the said step (3), the weighing accuracy of the cast billet is the target weight ±5kg; except for special cases, each directly rolled cast billet is weighed, and the weighing rate of the cast billet is greater than 98%.

[0017] The said special cases include starting casting or stopping casting.

[0018] In practical applications, the present invention is applicable to a billet continuous casting machine with a cross-section of 150mm×150mm to 180mm×180mm, an arc radius of the cast billet of 9 - 12m, a drawing speed of the continuous casting machine of 3.5 - 4.5m / min under normal production conditions, and a specified length of the weighed cast billet of 10 - 12 meters.

[0019] The continuously cast billets produced by the small billet continuous casting machine are not heated in a heating furnace. After weighing the cut cast billets, they are directly rolled.

[0020] The fixed-weight weighing device is installed between the flame cutting machine / hydraulic shear and the billet transfer car. The weighing cycle for a single cast billet is 9 - 13 seconds, and the waiting time for a single cast billet is less than 60 seconds. When weighing the cast billet, it does not affect its normal direct rolling. When the rolling mill produces φ12 - 16mm bars, the hourly output is not less than 220t / h, and when producing φ18 - 32mm bars, the hourly output is not less than 240t / h.

[0021] The weighing accuracy of the continuously cast billet is the target weight (-5kg, +5kg), and the fixed-weight rate meeting this standard is greater than 82%. Except for special cases (such as starting casting, stopping casting), each directly rolled cast billet is weighed, and the weighing rate of the cast billet is greater than 98%.

[0022] After weighing this cast billet, its weight is input into the weighing model to calculate the length of the next cast billet, and then it is sent to the specified length control system for cutting.

[0023] The present invention stabilizes the direct rolling mode of continuously cast small billets. By precisely controlling the weight of each continuously cast billet, it reduces the non-specified-length materials of straight bars / coil bars, enables smooth production, solves the situation of excessive difference in non-specified-length materials caused by different weights of continuously cast billets, not only improves the yield rate of cast billets, but also reduces the non-specified-length materials generated during rolling, and has a wide prospect of popularization and application.

Claims

1. A method for supplying billets with fixed weight in the direct rolling mode of continuous casting small square billets, characterized in that It includes the following steps: (1) Install a fixed-weight weighing device between the flame cutting machine / hydraulic shears and the billet transfer car to weigh the weight of each billet in real time; (2) Set the weighing cycle for each strand of billets; (3) Set the weighing accuracy of the billets, and weigh each strand of billets separately; (4) After the billets are weighed, send them to the fixed-length control system for cutting; (5) Adjust the weight of the next billet according to the length of the non-fixed-length material after rolling of each billet.

2. A method for supplying billets with fixed weight in the direct rolling mode of continuous casting small square billets, characterized in that: The cross-section of the billet continuous casting machine is 150mm×150mm to 180mm×180mm, the arc radius of the billet is 9 - 12m, the drawing speed of the continuous casting machine under normal production is 3.5 - 4.5m / min, and the fixed length of the weighed billet is 10 - 12 meters.

3. A method for supplying billets with fixed weight in the direct rolling mode of continuous casting small square billets, characterized in that: In the step (2), the weighing cycle for a single billet is 9 - 13 seconds, and the waiting time for a single billet is less than 60 seconds.

4. A method for supplying billets with fixed weight in the direct rolling mode of continuous casting small square billets, characterized in that: In the step (3), the weighing accuracy of the billets is the target weight ±5kg; except for special cases, each direct-rolled billet is weighed, and the weighing rate of the billets is greater than 98%.

5. A method for supplying billets with fixed weight in the direct rolling mode of continuous casting small square billets, characterized in that: The special cases include starting casting or stopping casting.

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