Control method for effectively improving hot conveying and hot charging efficiency of thin-specification pickled plate

Abstract

The invention discloses a control method for effectively improving the hot delivery and hot charging efficiency of a thin-specification pickled plate, which comprises the following steps of: presetting two continuous casting machine division rolling production lines, namely a 2250 production line and a 1780 production line; the molten steel is conveyed to a continuous casting machine for casting, multi-furnace tapping is controlled through single casting, and a plate blank is obtained; the slabs are conveyed to a hot-rolled slab yard, the slab cutting time is dynamically tracked, if it is judged that the slabs can be loaded into a heating furnace within 4 hours, the slabs are firstly stacked in a stacking position in a concentrated mode and loaded into the heating furnace in batches, and if it is judged that the slabs can be loaded into the heating furnace within 4 hours, the slabs are firstly stacked in a slow cooling area in a concentrated mode; and the steel is charged into a heating furnace in batches within 10 hours, and a rolling plan of the steel tapping amount of the plate blank is arranged. The method can increase the charging temperature of the plate blank, shorten the heating time of the plate blank, reduce the fuel input for heating the plate blank and the fuel consumption per ton of steel, improve the rolling stability of the thin plate, reduce the steel scrap frequency and the rolling breaking rate, and reduce the manufacturing cost of the pickled plate.

Description

Technical Field

[0001] The invention relates to the technical field of hot-rolled pickled plates in the metallurgical industry, and in particular to a control method for effectively improving the efficiency of hot delivery and hot loading of thin-gauge pickled plates. Background Art

[0002] Pickling plate is an intermediate product with surface quality and use requirements between hot-rolled plate and cold-rolled plate after the pickling unit removes the oxide layer, trims and finishes. It is also a product with a relatively high performance price between hot-rolled plate and cold-rolled plate. Compared with hot-rolled plate, the advantages of pickling plate are: good surface quality, because the hot-rolled pickling plate removes the surface oxide scale, improves the surface quality of steel, and is convenient for welding, oiling and painting; high dimensional accuracy, after balancing, the plate shape can change to a certain extent, thereby reducing the deviation of unevenness; improve the surface finish and enhance the appearance effect; can reduce the environmental pollution caused by user scattered pickling. Compared with cold-rolled plate, the advantages of pickling plate are: under the premise of ensuring the surface quality use requirements, users can effectively reduce the procurement cost. It is widely used in automotive parts, light industrial appliances, highway guardrails and other aspects.

[0003] At present, with the expansion of hot-rolled plates to thin specifications, the production demand for thin-gauge pickled plates is gradually increasing. However, due to the high surface quality requirements of thin-gauge pickled plates, especially the finished product thickness requirement of less than 2.1mm and the thin-gauge pickled plates with a tensile strength of ≤590MPa, the overall production is difficult. There are generally problems such as great rolling difficulty and insufficient transition materials. The furnace cannot be loaded and produced quickly, resulting in cooling of the slab. At the same time, the cold slab cannot be burned through, resulting in scrap steel or rolling breakage, which leads to low production efficiency, poor production stability, low finished product quality and high production cost in the production process of thin-gauge pickled plates. Summary of the invention

[0004] The purpose of the present invention is to provide a control method for effectively improving the efficiency of hot delivery and hot loading of thin-gauge pickled plates, which can improve production stability, production efficiency and product yield rate, and achieve the purpose of reducing enterprise production costs.

[0005] In order to achieve the above object, the present invention adopts the following technical solution: A control method for effectively improving the efficiency of hot delivery and hot loading of thin-gauge pickled plates comprises the following steps: S1: Two continuous casting machine division rolling production lines are pre-set, namely, the 2250 production line and the 1780 production line, wherein the 2250 production line is set to give priority to rolling non-high-strength pickled thin plates, and the 1780 production line is set to give priority to rolling high-strength pickled thin plates; S2: transporting molten steel to the continuous casting machine for casting, controlling the steel tapping from multiple furnaces in a single casting to obtain slabs; S3: transport the slab to the hot-rolled slab warehouse and dynamically track the slab cutting time. If it is predicted that the slab can be loaded into the heating furnace within 4 hours, execute step S5; if it is predicted that the slab will take more than 4 hours to be loaded into the heating furnace, execute step S4; S4: After entering the hot-rolled slab warehouse, the slabs are centrally stacked in the slow cooling zone, and step S5 is performed within 10 hours; S5: According to the specifications and process of the slabs and the number of continuous rolling blocks in the actual production line, the slabs are divided into batches and loaded into the heating furnace in sequence. At the same time, the rolling plan is formulated by adjusting and arranging the steel output of the slabs; S6: Formulate a rolling plan based on the steel output of the slab. If the multi-furnace slabs obtained in step S2 are thin slabs from 2 furnaces and non-thin slabs from 3 furnaces, or the number of steel output furnaces in step S2 reaches more than 4 furnaces, the slabs are directly rolled. Otherwise, the slabs are diverted to the 2250 production line and the 1780 production line for rolling. The rolling thickness of the thin slabs is less than or equal to 2.1 mm, and the rolling thickness of the non-thin slabs is greater than 2.1 mm.

[0006] Furthermore, in the step S1, the 2250 production line and the 1780 production line are both linear logistics production lines, and are respectively equipped with two continuous casting machines.

[0007] Furthermore, in the step S1, the 1780 production line is equipped with a hot coil box device.

[0008] Furthermore, in the step S4, the slow cooling zone is provided with a heat preservation pit or a heat preservation furnace for centralized stacking of slabs.

[0009] Furthermore, in the step S5, the current batch of slabs is loaded into the heating furnace, and the remaining batches of slabs are concentratedly stacked in the stacks of the hot-rolled slab warehouse, waiting to be loaded into the heating furnace.

[0010] Furthermore, the specifications of the pickled thin plate are: the finished product thickness is less than 2.1 mm, and the tensile strength is less than or equal to 590 MPa.

[0011] Beneficial effects of the present invention: 1. This method uses casting, hot delivery, stacking, hot charging and rolling as process steps, organically combines the steelmaking process with the hot rolling process, reduces the production difficulty of thin-gauge pickled plates, and at the same time realizes the shortest slab logistics division production line, increases the number of continuous rolling blocks of thin-gauge pickled plates, and is conducive to improving the production stability and production efficiency of thin-gauge pickled plates.

[0012] 2. Starting from steelmaking and casting, it is planned to adopt a steel-making mode of 2 furnaces of thin plate slabs + 3 furnaces of non-thin plate slabs to reduce the number of furnaces for single thin plate continuous casting and effectively ensure the stable production of thin plates on a single production line.

[0013] 3. Improve the efficiency of hot delivery and hot loading by centralized stacking and production line diversion, so that the charging temperature of the slab can be maintained above 400°C, increase the average charging temperature of the slab, effectively reduce the temperature drop of the slab, reduce the fuel input for heating the slab, and reduce the fuel consumption per ton of steel. In this way, the heating time of the slab is shortened, the number of scrap steel generation is reduced, and the rolling rate is reduced, thereby significantly improving the rolling stability of thin plates, improving the production efficiency and yield rate of products, and reducing the production costs of enterprises. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present invention are described below.

[0015] A control method for effectively improving the efficiency of hot delivery and hot loading of thin-gauge pickled plates comprises the following steps: S1: Two continuous casting machine division rolling production lines are pre-set, namely, the 2250 production line and the 1780 production line, wherein the 2250 production line is set to give priority to rolling non-high-strength pickled thin plates, and the 1780 production line is set to give priority to rolling high-strength pickled thin plates; S2: transporting molten steel to the continuous casting machine for casting, controlling the steel tapping from multiple furnaces in a single casting to obtain slabs; S3: transport the slab to the hot-rolled slab warehouse and dynamically track the slab cutting time. If it is predicted that the slab can be loaded into the heating furnace within 4 hours, execute step S5; if it is predicted that the slab will take more than 4 hours to be loaded into the heating furnace, execute step S4; S4: After entering the hot-rolled slab warehouse, the slabs are centrally stacked in the slow cooling zone, and step S5 is performed within 10 hours; S5: According to the specifications and process of the slabs and the number of continuous rolling blocks in the actual production line, the slabs are divided into batches and loaded into the heating furnace in sequence. At the same time, the rolling plan is formulated by adjusting and arranging the steel output of the slabs; S6: Formulate a rolling plan based on the steel output of the slab. If the multi-furnace slabs obtained in step S2 are thin slabs from 2 furnaces and non-thin slabs from 3 furnaces, or the number of steel output furnaces in step S2 reaches more than 4 furnaces, the slabs are directly rolled. Otherwise, the slabs are diverted to the 2250 production line and the 1780 production line for rolling. The rolling thickness of the thin slabs is less than or equal to 2.1 mm, and the rolling thickness of the non-thin slabs is greater than 2.1 mm.

[0016] Furthermore, in the step S1, the 2250 production line and the 1780 production line are both linear logistics production lines, and are respectively equipped with two continuous casting machines.

[0017] Furthermore, in the step S1, the 1780 production line is equipped with a hot coil box device.

[0018] Furthermore, in the step S4, the slow cooling zone is provided with a heat preservation pit or a heat preservation furnace for centralized stacking of slabs.

[0019] Furthermore, in the step S5, the slabs of the current batch are first loaded into the heating furnace, and the slabs of the remaining batches are concentratedly stacked in the stacks of the hot-rolled slab warehouse, waiting to be loaded into the heating furnace.

[0020] Furthermore, the specifications of the pickled thin plate are: the finished product thickness is less than 2.1 mm, and the tensile strength is less than or equal to 590 MPa.

[0021] It should be noted that in the step S1, the 2250 production line can continuously roll 30 thin plate slabs with a thickness of less than 2.1 mm, and can continuously roll 15 thin plate slabs with a thickness of less than 1.5 mm; the 1780 production line can continuously roll 35 thin plate slabs with a thickness of less than 2.1 mm, and can continuously roll 20 thin plate slabs with a thickness of less than 1.5 mm.

[0022] It should be noted that in the step S2, the method requires a single casting to control the steel output from multiple furnaces. In the actual production process, the number of steel output furnaces and the specification control of the slabs are unstable. Based on the actual production situation of the slabs, each slab is rolled in a separate stream, which can effectively ensure the stable production of the production line, reduce the rolling production cost, and ensure the rolling quality of the slabs.

[0023] It should be noted that, in step S4, the holding pit and the holding furnace can achieve a better slow cooling effect and prevent the temperature of the slab from dropping too quickly.

[0024] It should be noted that in step S5, the slabs enter the heating furnace in batches, which can ensure the hot charging quality of the slabs and facilitate subsequent unified rolling processing. The slabs waiting to be loaded into the furnace can be slowly cooled by stacking them together at the stack position, which is convenient for nearby loading into the furnace.

[0025] It should be understood that this method uses casting, hot delivery, stacking, hot charging and rolling as process steps, organically combines the steelmaking process with the hot rolling process, reduces the production difficulty of thin-gauge pickled plates, and at the same time realizes the shortest slab logistics division production line, increases the number of continuous rolling blocks of thin-gauge pickled plates, and is conducive to improving the production stability and production efficiency of thin-gauge pickled plates.

[0026] It should be understood that starting from steelmaking and casting, it is planned to adopt a steelmaking mode of 2 furnaces of thin plate slabs + 3 furnaces of non-thin plate slabs to reduce the number of furnaces for single thin plate continuous casting and effectively ensure the stable production of thin plates on a single production line.

[0027] It should be understood that this method improves the efficiency of hot delivery and hot loading by centralized stacking and production line diversion, so that the charging temperature of the slab can be maintained above 400°C, the average charging temperature of the slab is increased, the temperature drop of the slab is effectively reduced, and the fuel input for heating the slab from room temperature to 1230°C in the heating furnace is reduced, thereby reducing the fuel consumption per ton of steel, thereby shortening the heating time of the slab, reducing the number of scrap steel generation times, and reducing the rolling rate, thereby significantly improving the rolling stability of the thin plate, improving the production efficiency and yield rate of the product, and reducing the production cost of the enterprise.

Claims

1. A control method for effectively improving the efficiency of hot delivery and hot loading of thin-gauge pickled plates, characterized in that: The following steps are involved: S1: Two continuous casting machine division rolling production lines are pre-set, namely, the 2250 production line and the 1780 production line, wherein the 2250 production line is set to give priority to rolling non-high-strength pickled thin plates, and the 1780 production line is set to give priority to rolling high-strength pickled thin plates; S2: transporting molten steel to the continuous casting machine for casting, controlling the steel tapping from multiple furnaces in a single casting to obtain slabs; S3: transport the slab to the hot-rolled slab warehouse and dynamically track the slab cutting time. If it is predicted that the slab can be loaded into the heating furnace within 4 hours, execute step S5; if it is predicted that the slab will take more than 4 hours to be loaded into the heating furnace, execute step S4; S4: After entering the hot-rolled slab warehouse, the slabs are centrally stacked in the slow cooling zone, and step S5 is performed within 10 hours; S5: According to the specifications and process of the slabs and the number of continuous rolling blocks in the actual production line, the slabs are divided into batches and loaded into the heating furnace in sequence. At the same time, the rolling plan is formulated by adjusting and arranging the steel output of the slabs; S6: Formulate a rolling plan based on the steel output of the slab. If the multi-furnace slabs obtained in step S2 are thin slabs from 2 furnaces and non-thin slabs from 3 furnaces, or the number of steel output furnaces in step S2 reaches more than 4 furnaces, the slabs are directly rolled. Otherwise, the slabs are diverted to the 2250 production line and the 1780 production line for rolling. The rolling thickness of the thin slabs is less than or equal to 2.1 mm, and the rolling thickness of the non-thin slabs is greater than 2.1 mm.

2. The control method for effectively improving the efficiency of hot delivery and hot loading of thin-gauge pickled plates according to claim 1 is characterized in that: In the step S1, the 2250 production line and the 1780 production line are both linear logistics production lines, and are respectively equipped with two continuous casting machines.

3. The control method for effectively improving the efficiency of hot delivery and hot loading of thin-gauge pickled plates according to claim 1 or 2, characterized in that: In the step S1, the 1780 production line is equipped with a hot coil box device.

4. The control method for effectively improving the efficiency of hot delivery and hot loading of thin-gauge pickled plates according to claim 1 is characterized in that: In the step S4, the slow cooling zone is provided with a heat preservation pit or a heat preservation furnace for centralized stacking of slabs.

5. The control method for effectively improving the efficiency of hot delivery and hot loading of thin-gauge pickled plates according to claim 1 is characterized in that: In the step S5, the current batch of slabs is first loaded into the heating furnace, and the remaining batches of slabs are concentratedly stacked in the stacks of the hot-rolled slab warehouse, waiting to be loaded into the heating furnace.

6. The control method for effectively improving the efficiency of hot delivery and hot loading of thin-gauge pickled plates according to claim 1 is characterized in that: The specifications of the pickled thin plate are: the finished product thickness is less than 2.1 mm, and the tensile strength is less than or equal to 590 MPa.