Low-cost 380CL steel coil and preparation method thereof

Abstract

The invention provides a low-cost 380CL steel coil and a preparation method thereof, and relates to the technical field of steel production. The low-cost 380CL steel coil comprises the following chemical components in percentage by weight: 0.11-0.15 wt% of C, less than or equal to 1wt% of Mn, less than or equal to 0.08 wt% of Si, less than or equal to 0.03 wt% of P, less than or equal to 0.02 wt% of S, 0.003-0.03 wt% of Als, less than or equal to 0.3 wt% of Cr, less than or equal to 0.3 wt% of Cu, less than or equal to 0.3 wt% of Ni, less than or equal to 0.1 wt% of Mo and the balance of Fe. B: less than or equal to 0.001 wt%, with the balance being iron and inevitable impurities. The low-cost 380CL steel coil is prepared by the following steps: firstly selecting a continuous casting billet, and then sequentially carrying out a heating process, a rough rolling process, a finish rolling process and a coiling process, thereby finally preparing the low-cost 380CL steel coil. The low-cost 380CL steel coil is good in surface quality, good in strength and toughness matching and good in descaling effect, the production process is simple, the alloy cost is low, the production cost of 380CL is effectively reduced, and the yield is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of steel production, and in particular to a low-cost 380CL steel coil and a preparation method thereof. Background Art

[0002] Steel coils have a wide range of applications. In the construction industry, steel coils are often used to make structural components such as roofs, walls and floors. Their high strength and weather resistance allow them to maintain stable performance in harsh climate conditions. Steel coils are also commonly used to make chassis and bodies of cars, which require steel coils to have high strength, toughness and corrosion resistance to ensure the safety and durability of the car. Steel coils are also used to manufacture home appliances such as washing machines, refrigerators, water heaters, etc., because their stability and durability allow home appliances to operate normally for a long time. In addition, steel coils are also widely used in many fields such as machinery manufacturing, shipbuilding, and energy.

[0003] The use of steel coils in modern industry has important economic and environmental significance. First of all, the production of steel coils is an important part of the steel industry and has played a role in promoting economic development. High-quality steel coil products are in great demand both at home and abroad, so steel coil manufacturing companies play an important role in employment and economic growth. Secondly, the use of steel coils also helps to reduce resource waste and environmental pollution. Steel coils can be recycled and reused to reduce the demand for new steel, thereby reducing the mining of mineral resources and environmental damage. In addition, the long life cycle and high durability of steel coils reduce product updates and waste generation, and play a positive role in environmental protection.

[0004] With the continuous advancement of science and technology and the development of industry, the quality and variety of steel coils are also constantly improving. Innovative steel coil products not only have the characteristics of traditional steel coils, but also have better performance, such as high temperature resistance, wear resistance, electrical and thermal conductivity, etc. The application of steel coils in various fields is becoming more and more extensive, which also promotes the progress of industrial technology and economic development. Therefore, how to effectively reduce the production cost of steel coils while ensuring the quality of steel coils is the key to optimizing steel coils at present. Summary of the invention

[0005] In view of this, the present invention provides a low-cost 380CL steel coil and a preparation method thereof. The steel coil has good surface quality, low alloy cost, good strength and toughness matching, and a simple production process, which effectively reduces the production cost of 380CL.

[0006] The present invention is achieved by adopting the following technical solutions:

[0007] A low cost 380CL steel coil comprising the following chemical composition in weight percentage:

[0008] C: 0.11wt%~0.15wt%, Mn: ≤1wt%, Si: ≤0.08wt%, P: ≤0.03wt%, S: ≤0.02wt%, Als: 0.003wt%~0.03wt%, Cr: ≤0.3wt%, Cu: ≤0.3wt%, Ni: ≤0.3wt%, Mo: ≤0.1wt%; B: ≤0.001wt%, the rest are iron and unavoidable impurities.

[0009] The method for preparing the low-cost 380CL steel coil is to first select a continuous casting billet, and then sequentially perform a heating process, a rough rolling process, a finish rolling process and a coiling process to finally prepare the low-cost 380CL steel coil.

[0010] Preferably, the thickness of the continuous casting slab is 220 mm to 260 mm to ensure a certain compression ratio and slab quality.

[0011] Furthermore, the heating process is to heat the continuous casting billet using a walking beam heating furnace.

[0012] Preferably, the heating temperature is 1260°C-1270°C, the heating time is 80min-100min, the temperature of the continuous casting billet out of the furnace during the heating process is 1080°C-1120°C, and the moving speed of the movable beam supporting the continuous casting billet when the continuous casting billet is heated in the heating furnace is 1.25m / min.

[0013] Furthermore, the rough rolling process is a five-pass rolling process.

[0014] Preferably, the rough rolling start temperature is 1070℃-1110℃, and the rough rolling final rolling temperature is 1030℃-1060℃; the flat roll torque is set to 3127.99KNm in the first pass, and the flat roll torque is set to 1314.25KNm in the last pass; the flat roll reduction rate is set to 28% in the first pass, and the flat roll reduction rate is set to 30% in the last pass; the flat roll gap is set to 165.89mm in the first pass, and the flat roll gap is set to 39.43mm in the last pass.

[0015] Furthermore, the finishing rolling process is a five-pass rolling process.

[0016] Preferably, the start temperature of the finishing rolling is between 970°C and 990°C, and the final temperature of the finishing rolling is between 780°C and 790°C; the rolling mill power is set to 875.65KW for the first pass, and to 784.12KW for the last pass; the reduction rate is set to 18% for the first pass, and to 14% for the last pass; the threading speed is set to 0.81m / s for the first pass, and to 1.70m / s for the last pass.

[0017] Furthermore, the curling temperature is set at 610°C, the cooling method adopts front-stage group sparse + hot head, the hot head length is 10m, and the hot head temperature rise is 50°C.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The low-cost 380CL steel coil of the present invention not only has good surface quality, good matching of strength and toughness, and good descaling effect, but also has a simple production process and low alloy cost, which not only effectively reduces the production cost of 380CL, but also improves the yield rate. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the embodiments.

[0021] Example 1

[0022] A method for preparing a low-cost 380CL steel coil, the specific steps are as follows:

[0023] 1. A continuous casting billet with a thickness of 230 mm is selected to ensure a certain compression ratio and billet quality; the continuous casting billet includes the following chemical components in weight percentage:

[0024] C: 0.11wt%, Mn: 1.0wt%, Si: 0.08wt%, P: 0.03wt%, S: 0.02wt%, Als: 0.03wt%, Cr: 0.3wt%, Cu: 0.3wt%, Ni: 0.3wt%, Mo: 0.1wt%; B: 0.001wt%, the rest are iron and unavoidable impurities.

[0025] 2. Heating process: 230mm thick continuous casting billet is used for slab heating treatment. Specifically, a walking beam heating furnace is used to heat the continuous casting billet to 1260℃ and keep it warm for 90 minutes; after the temperature is reduced to 1110℃, the continuous casting billet is taken out of the furnace; when the billet is heated in the heating furnace, the moving speed of the movable beam holding up the billet is 1.25m / min.

[0026] 3. Rough rolling process: The continuous casting billet out of the furnace is rough rolled, and the rough rolling is five passes. The starting rolling temperature of the rough rolling is 1110℃, and the final rolling temperature of the rough rolling is 1050℃. The flat roll torque is set to 3127.99KNm in the first pass, and the flat roll torque is set to 1314.25KNm in the last pass. The flat roll reduction rate is set to 28% in the first pass, and the flat roll reduction rate is set to 30% in the last pass. The flat roll gap is set to 165.89mm in the first pass, and the flat roll gap is set to 39.43mm in the last pass.

[0027] 4. Finishing rolling process: The slab after rough rolling is subjected to finish rolling, and the rolling process is also performed in five passes. The start rolling temperature of the finishing rolling is 980°C, the final rolling temperature of the finishing rolling is 780°C, the mill power is set to 875.65KW for the first pass, and the mill power is set to 784.12KW for the last pass. The reduction rate is set to 18% for the first pass, and 14% for the last pass. The strip threading speed is set to 0.81m / s for the first pass, and 1.70m / s for the last pass.

[0028] 5. Curling process: Curl the plate after fine rolling, where the curling temperature is set to 610°C, and the cooling method adopts front-stage group sparse + hot head, the hot head length is 10 meters, and the hot head temperature rise is 50°C.

[0029] Example 2

[0030] A method for preparing a low-cost 380CL steel coil, the specific steps are as follows:

[0031] 1. A continuous casting billet with a thickness of 250 mm is selected to ensure a certain compression ratio and billet quality; the continuous casting billet includes the following chemical components in weight percentage:

[0032] C: 0.12wt%, Mn: 0.82wt%, Si: 0.071wt%, P: 0.025wt%, S: 0.01wt%, Als: 0.008wt%, Cr: 0.25wt%, Cu: 0.15wt%, Ni: 0.10wt%, Mo: 0.06wt%; B: 0.001wt%, the rest are iron and unavoidable impurities.

[0033] 2. Heating process: 250mm thick continuous casting billet is used for slab heating treatment. Specifically, a walking beam heating furnace is used to heat the continuous casting billet to 1270℃ and keep it warm for 80 minutes; after the temperature is reduced to 1120℃, the continuous casting billet is taken out of the furnace; when the billet is heated in the heating furnace, the moving speed of the movable beam holding up the billet is 1.25m / min.

[0034] 3. Rough rolling process: The continuous casting billet out of the furnace is subjected to rough rolling, and the rough rolling is performed in five passes. The starting rolling temperature of the rough rolling is 1110°C, and the final rolling temperature of the rough rolling is 1060°C. The flat roll torque is set to 3127.99KNm in the first pass, and the flat roll torque is set to 1314.25KNm in the last pass. The flat roll reduction rate is set to 28% in the first pass, and the flat roll reduction rate is set to 30% in the last pass. The flat roll gap is set to 165.89mm in the first pass, and the flat roll gap is set to 39.43mm in the last pass.

[0035] 4. Finishing rolling process: The slab after rough rolling is subjected to finish rolling, and the rolling process is also performed in five passes. The start rolling temperature of the finishing rolling is 990°C, the final rolling temperature of the finishing rolling is 780°C, the mill power is set to 875.65KW for the first pass, and the mill power is set to 784.12KW for the last pass. The reduction rate is set to 18% for the first pass, and 14% for the last pass. The strip threading speed is set to 0.81m / s for the first pass, and 1.70m / s for the last pass.

[0036] 5. Curling process: Curl the plate after fine rolling, where the curling temperature is set to 610°C, and the cooling method adopts front-stage group sparse + hot head, the hot head length is 10 meters, and the hot head temperature rise is 50°C.

[0037] Example 3

[0038] A method for preparing a low-cost 380CL steel coil, the specific steps are as follows:

[0039] 1. A continuous casting billet with a thickness of 260 mm is selected to ensure a certain compression ratio and billet quality; the continuous casting billet includes the following chemical components in weight percentage:

[0040] 0.15wt%, Mn: 0.75wt%, Si: 0.05wt%, P: 0.028wt%, S: 0.015wt%, Als: 0.003wt%, Cr: 0.20wt%, Cu: 0.20wt%, Ni: 0.10wt%, Mo: 0.05wt%; B: 0.001wt%, the rest are iron and unavoidable impurities.

[0041] 2. Heating process: 260mm thick continuous casting billet is used for slab heating treatment. Specifically, a walking beam heating furnace is used to heat the continuous casting billet to 1260℃ and keep it warm for 90 minutes; after the temperature is reduced to 1110℃, the continuous casting billet is taken out of the furnace; when the billet is heated in the heating furnace, the moving speed of the movable beam holding up the billet is 1.25m / min.

[0042] 3. Rough rolling process: The continuous casting billet out of the furnace is rough rolled, and the rough rolling is five passes. The starting rolling temperature of the rough rolling is 1110℃, and the final rolling temperature of the rough rolling is 1050℃. The flat roll torque is set to 3127.99KNm in the first pass, and the flat roll torque is set to 1314.25KNm in the last pass. The flat roll reduction rate is set to 28% in the first pass, and the flat roll reduction rate is set to 30% in the last pass. The flat roll gap is set to 165.89mm in the first pass, and the flat roll gap is set to 39.43mm in the last pass.

[0043] 4. Finishing rolling process: The slab after rough rolling is subjected to finish rolling, and the rolling process is also performed in five passes. The start rolling temperature of the finishing rolling is 980°C, the final rolling temperature of the finishing rolling is 780°C, the mill power is set to 875.65KW for the first pass, and the mill power is set to 784.12KW for the last pass. The reduction rate is set to 18% for the first pass, and 14% for the last pass. The strip threading speed is set to 0.81m / s for the first pass, and 1.70m / s for the last pass.

[0044] 5. Curling process: Curl the plate after fine rolling, where the curling temperature is set to 610°C, and the cooling method adopts front-stage group sparse + hot head, the hot head length is 10 meters, and the hot head temperature rise is 50°C.

[0045] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A low-cost 380CL steel coil, characterized in that: It is processed from continuous casting billets with the following chemical compositions in weight percentage: C: 0.11wt%~0.15wt%, Mn: ≤1wt%, Si: ≤0.08wt%, P: ≤0.03wt%, S: ≤0.02wt%, Als: 0.003wt%~0.03wt%, Cr: ≤0.3wt%, Cu: ≤0.3wt%, Ni: ≤0.3wt%, Mo: ≤0.1wt%; B: ≤0.001wt%, the rest are iron and unavoidable impurities.

2. The method for preparing low-cost 380CL steel coil according to claim 1, characterized in that: The continuous casting billet is subjected to a heating process, a rough rolling process, a finishing rolling process and a coiling process in sequence, and finally a low-cost 380CL steel coil is produced.

3. The method for preparing low-cost 380CL steel coil according to claim 2, characterized in that: The thickness of the continuous casting billet is 220 mm to 260 mm.

4. The method for preparing low-cost 380CL steel coil according to claim 2, characterized in that: The heating process is to heat the continuous casting billet by using a walking beam heating furnace.

5. The method for preparing low-cost 380CL steel coil according to claim 4, characterized in that: The heating temperature is 1260°C-1270°C, and the heating time is 80min-100min; in the heating process, the temperature of the continuous casting billet out of the furnace is 1080°C-1120°C, and the moving speed of the movable beam supporting the continuous casting billet when the continuous casting billet is heated in the heating furnace is 1.25m / min.

6. The method for preparing low-cost 380CL steel coil according to claim 2, characterized in that: The rough rolling process is a five-pass rolling process.

7. The method for preparing low-cost 380CL steel coil according to claim 6, characterized in that: The starting temperature of rough rolling is 1070℃-1110℃, and the finishing temperature of rough rolling is 1030℃-1060℃; the flat roll torque is set to 3127.99KNm in the first pass, and the flat roll torque is set to 1314.25KNm in the last pass; the flat roll reduction rate is set to 28% in the first pass, and the flat roll reduction rate is set to 30% in the last pass; the flat roll gap is set to 165.89mm in the first pass, and the flat roll gap is set to 39.43mm in the last pass.

8. The method for preparing low-cost 380CL steel coil according to claim 2, characterized in that: The finishing rolling process is a five-pass rolling process.

9. The method for preparing low-cost 380CL steel coil according to claim 8, characterized in that: The start temperature of finishing rolling is between 970℃ and 990℃, and the final temperature of finishing rolling is between 780℃ and 790℃; the rolling mill power is set to 875.65KW for the first pass, and to 784.12KW for the last pass; the reduction rate is set to 18% for the first pass, and to 14% for the last pass; the strip threading speed is set to 0.81m / s for the first pass, and to 1.70m / s for the last pass.

10. The method for preparing low-cost 380CL steel coil according to claim 2, characterized in that: The curling temperature is set at 610°C, the cooling method adopts front-stage group sparse + hot head, the hot head length is 10m, and the hot head temperature rise is 50°C.