Control method for reducing edge thickness of galvanized plate with super-thick zinc layer

Abstract

The invention relates to a control method for reducing the edge thickness of a galvanized plate with an ultra-thick zinc layer, and belongs to the technical field of production of ultra-thick zinc layer products in the metallurgical industry. According to the technical scheme, control is conducted according to the following steps that (1) a hot-rolled plate serves as a base plate, and the thickness of the zinc layer is larger than or equal to 500 g / m<2>; (2) the convexity of the hot-rolled plate adopts positive convexity, specifically, the value of the positive convexity is 40-70 microns; (3) it is ensured that the end part is smooth and burr-free after the hot-rolled plate is trimmed; (4) the annealing temperature of the hot-rolled plate is 670-690 DEG C, and the temperature of the hot-rolled plate entering a zinc pot is 460-465 DEG C; and (5) on the basis of 1.2-1.4 mm in the middle, an air knife gap is gradually increased towards the two ends by the increment of 0.02-0.3 mm till the air knife gap is increased to 1.5-1.7 mm. The control method has the beneficial effects that the edge thickness can be reduced, the thickness difference of the galvanized plate is reduced, and the defects such as waves are avoided.

Description

technical field

[0001] The invention relates to a control method for reducing side thickness of an ultra-thick zinc layer galvanized sheet, belonging to the technical field of production of ultra-thick zinc layer products in the metallurgical industry. Background technique

[0002] As a deep-processing high value-added product in the metallurgical industry, galvanized sheet has the characteristics of strong corrosion resistance, excellent surface quality, good processing performance, and strong economic applicability, so it is widely used. With the rapid improvement of the national economy and the optimization and adjustment of the industrial structure, the vigorous development of emerging fields such as new energy and sponge cities has put forward higher requirements for the corrosion resistance of galvanized products, such as photovoltaic power stations built on the Gobi Desert, The comprehensive pipe gallery buried deep underground needs to ensure a sufficient service lif...

Examples

Embodiment 1

[0035] Galvanized sheet thickness specifications: 1.8mm, width 1500mm, zinc layer thickness 700g / ㎡, hot-rolled sheet as the substrate, convexity: 70μm, and after trimming, the end is smooth without burrs, and the annealing temperature is 670°C (plate Temperature), the temperature of entering the zinc pot is 465°C. The air knife gap is based on the middle 1.4mm, and gradually increases to both ends by 0.02-0.3mm, until it increases to 1.7mm and remains unchanged. The specific increments are: 0.02, 0.02, 0.03, 0.04, 0.06, 0.06, 0.08, 0.1, 0.12, 0.12, 0.14, 0.16, 0.2, 0.2, 0.2, 0.24, 0.24, 0.3, 0.3, 0.3mm, the gap value is shown in the table 1.

[0036] The air knife is a Posjet air knife with a lip length of 2000mm. It is treated with titanium nitride coating, which has the characteristics of high temperature resistance, not easy to adhere to zinc liquid, and easy to clean. The lip gap can be adjusted by manually adjusting the bolts, and the distance between each adjusting bol...

Embodiment 2

[0043] Galvanized sheet thickness specifications: 4.0mm, width 1500mm, zinc layer thickness 500g / ㎡, hot-rolled sheet as the substrate, convexity: 40μm, and after trimming, the end is smooth and burr-free. ), the temperature of entering the zinc pot is 460°C. The air knife gap is based on the 1.2mm in the middle, and gradually increases to the two ends with an increase of 0.02-0.3mm, until it increases to 1.5mm and remains unchanged. The specific increments are: 0.02, 0.02, 0.03, 0.04, 0.06, 0.06, 0.08, 0.1, 0.12, 0.12, 0.14, 0.16, 0.2, 0.2, 0.2, 0.24, 0.24, 0.3, 0.3, 0.3mm, the gap value is shown in the table 3. The air knife is the same as in Example 1.

[0044] The aluminum content in the zinc liquid composition needs to be controlled at 0.20%, the iron content ≤0.018%, the process speed is 30m / min, the air knife baffle is 2mm away from the edge of the strip steel, and after galvanizing, it goes through the skin pass process. 20μm, rolling force 4000KN. Before and after ...

Embodiment 3

[0050]Galvanized sheet thickness specifications: 3.0mm, width 1500mm, zinc layer thickness 600g / ㎡, hot-rolled sheet as the substrate, convexity: 50μm, and after trimming, the end is smooth and burr-free. ), the temperature of entering the zinc pot is 462°C. The air knife gap is based on the middle 1.3mm, and gradually increases to both ends by 0.02-0.3mm, until it increases to 1.6mm, it remains unchanged. The specific increments are: 0.02, 0.02, 0.03, 0.04, 0.06, 0.06, 0.08, 0.1, 0.12, 0.12, 0.14, 0.16, 0.2, 0.2, 0.2, 0.24, 0.24, 0.3, 0.3, 0.3mm, the gap value is shown in the table 5. The air knife is the same as in Example 1.

[0051] The aluminum content in the zinc liquid composition needs to be controlled at 0.22%, the iron content ≤0.018%, the process speed is 50m / min, the distance between the air knife baffle and the edge of the strip is 2mm, and after galvanizing, it goes through the skin pass process. 10μm, rolling force 3200KN. Before and after the implementation ...

technical field

[0001] The invention relates to a control method for reducing side thickness of an ultra-thick zinc layer galvanized sheet, belonging to the technical field of production of ultra-thick zinc layer products in the metallurgical industry. Background technique

[0002] As a deep-processing high value-added product in the metallurgical industry, galvanized sheet has the characteristics of strong corrosion resistance, excellent surface quality, good processing performance, and strong economic applicability, so it is widely used. With the rapid improvement of the national economy and the optimization and adjustment of the industrial structure, the vigorous development of emerging fields such as new energy and sponge cities has put forward higher requirements for the corrosion resistance of galvanized products, such as photovoltaic power stations built on the Gobi Desert, The comprehensive pipe gallery buried deep underground needs to ensure a sufficient service lif...

Examples

Embodiment 1

[0035] Galvanized sheet thickness specifications: 1.8mm, width 1500mm, zinc layer thickness 700g / ㎡, hot-rolled sheet as the substrate, convexity: 70μm, and after trimming, the end is smooth without burrs, and the annealing temperature is 670°C (plate Temperature), the temperature of entering the zinc pot is 465°C. The air knife gap is based on the middle 1.4mm, and gradually increases to both ends by 0.02-0.3mm, until it increases to 1.7mm and remains unchanged. The specific increments are: 0.02, 0.02, 0.03, 0.04, 0.06, 0.06, 0.08, 0.1, 0.12, 0.12, 0.14, 0.16, 0.2, 0.2, 0.2, 0.24, 0.24, 0.3, 0.3, 0.3mm, the gap value is shown in the table 1.

[0036] The air knife is a Posjet air knife with a lip length of 2000mm. It is treated with titanium nitride coating, which has the characteristics of high temperature resistance, not easy to adhere to zinc liquid, and easy to clean. The lip gap can be adjusted by manually adjusting the bolts, and the distance between each adjusting bol...

Embodiment 2

[0043] Galvanized sheet thickness specifications: 4.0mm, width 1500mm, zinc layer thickness 500g / ㎡, hot-rolled sheet as the substrate, convexity: 40μm, and after trimming, the end is smooth and burr-free. ), the temperature of entering the zinc pot is 460°C. The air knife gap is based on the 1.2mm in the middle, and gradually increases to the two ends with an increase of 0.02-0.3mm, until it increases to 1.5mm and remains unchanged. The specific increments are: 0.02, 0.02, 0.03, 0.04, 0.06, 0.06, 0.08, 0.1, 0.12, 0.12, 0.14, 0.16, 0.2, 0.2, 0.2, 0.24, 0.24, 0.3, 0.3, 0.3mm, the gap value is shown in the table 3. The air knife is the same as in Example 1.

[0044] The aluminum content in the zinc liquid composition needs to be controlled at 0.20%, the iron content ≤0.018%, the process speed is 30m / min, the air knife baffle is 2mm away from the edge of the strip steel, and after galvanizing, it goes through the skin pass process. 20μm, rolling force 4000KN. Before and after ...

Embodiment 3

[0050]Galvanized sheet thickness specifications: 3.0mm, width 1500mm, zinc layer thickness 600g / ㎡, hot-rolled sheet as the substrate, convexity: 50μm, and after trimming, the end is smooth and burr-free. ), the temperature of entering the zinc pot is 462°C. The air knife gap is based on the middle 1.3mm, and gradually increases to both ends by 0.02-0.3mm, until it increases to 1.6mm, it remains unchanged. The specific increments are: 0.02, 0.02, 0.03, 0.04, 0.06, 0.06, 0.08, 0.1, 0.12, 0.12, 0.14, 0.16, 0.2, 0.2, 0.2, 0.24, 0.24, 0.3, 0.3, 0.3mm, the gap value is shown in the table 5. The air knife is the same as in Example 1.

[0051] The aluminum content in the zinc liquid composition needs to be controlled at 0.22%, the iron content ≤0.018%, the process speed is 50m / min, the distance between the air knife baffle and the edge of the strip is 2mm, and after galvanizing, it goes through the skin pass process. 10μm, rolling force 3200KN. Before and after the implementation ...

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