Hot-dip galvanizing line strip steel parallel cooling system and method of using same
By designing a parallel cooling system, the problem of insufficient cooling capacity of the cold-rolled hot-dip galvanizing unit was solved, which improved the uniformity and quality of strip cooling, avoided quality defects caused by uneven cooling and vibration, and improved production efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-29
- Publication Date
- 2026-03-27
AI Technical Summary
The existing cooling devices of cold-rolled hot-dip galvanizing units have insufficient cooling capacity due to plant height restrictions, resulting in strip quality defects. Furthermore, increasing cooling efficiency can cause strip vibration, and existing methods require sacrificing output by reducing speed and extending cooling time.
A parallel cooling system is adopted, including a fan, air duct, airflow distributor and cooling device. The air is evenly distributed to multiple cooling devices through the air duct and airflow distributor. Combined with the buffer box to treat rainwater, it ensures that the cooling capacity of each cooling device is consistent and avoids uneven cooling and shaking in the width direction of the strip.
This technology improves cooling uniformity and efficiency without increasing the height of the plant, ensuring strip steel quality, avoiding quality problems caused by uneven cooling and vibration, and improving production efficiency.
Smart Images
Figure CN121737618A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of hot-dip galvanizing processes for sheets and strips using molten coating materials that do not affect their shape, specifically to a parallel cooling system for hot-dip galvanizing strips and its usage method. Background Technology
[0002] After being galvanized in a zinc pot, the strip steel of the cold-rolled hot-dip galvanizing unit is typically cooled at a temperature of around 530℃ to 580℃ depending on the process requirements. It then enters a quenching tank after being cooled by a cooling device (usually air cooling). Due to limitations such as plant height and cooling efficiency, the cooling device may not be able to cool the strip steel effectively, leading to defects in the strip steel quality.
[0003] Currently, common practices include increasing cooling capacity and improving the blowing efficiency of individual cooling devices. Increasing cooling capacity means continuously adding cooling devices along the strip's travel path, but due to plant height limitations, it's impossible to add one or more layers of cooling devices. Increasing the blowing efficiency of individual cooling devices means increasing the gas velocity sprayed onto the strip, which can lead to increased strip vibration or even the strip rubbing against the nozzles, affecting strip quality. Therefore, when encountering insufficient cooling capacity, current practices mostly involve sacrificing output by reducing the unit speed to extend the strip cooling time. Summary of the Invention
[0004] In order to overcome the shortcomings of the prior art and provide a plate processing method that achieves uniform cooling and improved quality, this invention discloses a parallel cooling system for hot-dip galvanizing strip steel and its usage method.
[0005] The present invention achieves its objective through the following technical solution: A parallel cooling system for hot-dip galvanizing strip steel, comprising a fan, characterized in that it further comprises air ducts, an airflow distributor, and a cooling device. The fan's air inlet is connected to the outside atmosphere, and the fan's air outlet is connected to the air inlet of the airflow distributor through a duct. The airflow distributor has at least three pairs of air outlets. Each pair of air outlets of the airflow distributor is connected to the two air inlets of a cooling device. The cooling device has a nozzle in the middle, so that the various cooling devices are connected in parallel within the airflow distributor.
[0006] The hot-dip galvanizing unit strip steel parallel cooling system is characterized in that: it also includes a buffer box, the bottom of which is an inclined plane with a downward direction towards the air inlet and a 2° to 5° angle with the horizontal plane, the axis of the air duct is obtuse, the buffer box is connected in series on the air duct and is located at the bend of the air duct, and the air outlet of the airflow distributor is equipped with a regulating valve and a pressure gauge.
[0007] The method of using the parallel cooling system for strip steel in the hot-dip galvanizing unit is characterized by the following steps being implemented sequentially: S1. Exhaust: The fan draws in outside air, pressurizes it, and then sends it to the air distributor through the duct; S2. Cooling: The airflow distributor ensures that the airflow velocity entering each cooling device is the same according to the number of parallel cooling devices, and ensures that the air pressure at the two air inlets of each cooling device is the same, thereby ensuring that each cooling device has the same cooling capacity. Each cooling device sprays air onto the strip through nozzles to cool the strip, so that the strip can be efficiently cooled to the process temperature in the cooling device.
[0008] The method of using the parallel cooling system for strip steel in the hot-dip galvanizing unit is characterized by the following steps being implemented sequentially: S1. Ventilation: The fan draws in the outside air and pressurizes it before it enters the airflow distributor through the duct. The air is slowed down by the zigzag duct and its flow rate is reduced in the buffer box, causing the rainwater mixed in the air to collect and fall in the buffer box. It then flows back to the air inlet through the inclined bottom of the buffer box and is discharged to the outside, preventing the quality of the strip steel from decreasing due to the mixing of rainwater. S2. Cooling: The airflow distributor ensures that the airflow velocity entering each cooling device is the same according to the number of parallel cooling devices, and ensures that the air pressure at the two air inlets of each cooling device is the same, thereby ensuring that each cooling device has the same cooling capacity. Each cooling device sprays air onto the strip through nozzles to cool the strip, so that the strip can be efficiently cooled to the process temperature in the cooling device.
[0009] The present invention has the following beneficial effects: 1. Higher site utilization: Existing technology requires cooling devices to be arranged one by one on a three-dimensional floor. To achieve the required cooling temperature of the strip steel, the cooling devices need to be arranged in many layers, which is difficult to achieve due to the height limitation of the factory building. This invention can arrange multiple cooling devices on the same floor, turning the three-dimensional cooling arrangement into a planar cooling arrangement. The strip steel can achieve the required cooling temperature by repeatedly passing through the parallel cooling devices.
[0010] 2. Enhanced uniformity of strip width cooling: Existing technologies use airflow distributors to deliver fresh air into the cooling device, but the airflow volume from left to right cannot be adjusted, which may lead to uneven cooling of the strip width, resulting in temperature differences and reduced product quality. This invention can adjust the airflow volume from left to right using a regulating valve, ensuring that the airflow is uniform in the strip width direction and preventing temperature differences in the strip width direction.
[0011] 3. This invention considers increasing cooling capacity from the perspective of existing space, without increasing the floor height of the existing factory building, and can achieve different cooling capacities according to process requirements.
[0012] 4. This invention avoids the problem of strip vibration caused by increasing the cooling efficiency of a single cooling device in traditional technologies, and also ensures the product quality of the strip. Attached Figure Description
[0013] Figure 1 This is the front view of the present invention. Figure 2 This is the left view of the present invention. Figure 3 This is a top view of the present invention. Figure 4 This is a schematic diagram of the buffer box in this invention. Detailed Implementation
[0014] The present invention will be further illustrated below through specific embodiments. Example
[0015] A parallel cooling system for hot-dip galvanizing strip steel includes a fan 1, a duct 2, an airflow distributor 3, and a cooling device 4, such as... Figures 1-4 As shown, the specific structure is: The air inlet of the fan 1 is connected to the outside atmosphere, and the air outlet of the fan 1 is connected to the air inlet of the airflow distributor 3 through the air duct 2. The airflow distributor 3 is provided with at least three pairs of air outlets. Each pair of air outlets of the airflow distributor 3 is connected to the two air inlets of a cooling device 4. The cooling device 4 is provided with a nozzle in the middle, so that each cooling device 4 is connected in parallel within the airflow distributor 3.
[0016] This embodiment also includes a buffer box 5, as shown in the example below. Figure 4 As shown: The bottom of the buffer box 5 is a downward slope towards the air inlet and at a 2° to 5° angle to the horizontal plane. The axis of the air duct 2 is obtuse. The buffer box 5 is connected in series with the air duct 2 and is located at the bend of the air duct 2. The air outlet of the air distributor 3 is equipped with a regulating valve and a barometer.
[0017] When using this embodiment, follow these steps in sequence: S1. Ventilation: Fan 1 draws in and pressurizes the outside air, then inputs it into airflow distributor 3 through duct 2. The air is slowed down by the zigzag duct 2 and its flow rate is reduced in the buffer box 5, causing rainwater mixed in the air to collect and fall in the buffer box 5. The rainwater then flows back to the air inlet through the inclined bottom of the buffer box 5 and is discharged to the outside, preventing the quality of the strip steel from decreasing due to the mixing of rainwater. S2. Cooling: The airflow distributor 3 ensures that the airflow velocity entering each cooling device 4 is the same according to the number of parallel cooling devices 4, and ensures that the air pressure at the two air inlets of each cooling device 4 is the same, thereby ensuring that each cooling device 4 has the same cooling capacity. Each cooling device 4 sprays air onto the strip through nozzles to cool the strip, so that the strip can be efficiently cooled to the process temperature in the cooling device 4.
Claims
1. A parallel cooling system for hot-dip galvanizing strip steel, comprising a fan (1), characterized in that: It also includes air ducts (2), airflow distributors (3), and cooling devices (4). The air inlet of the fan (1) is connected to the outside atmosphere, and the air outlet of the fan (1) is connected to the air inlet of the airflow distributor (3) through the air duct (2). The airflow distributor (3) is provided with at least three pairs of air outlets. Each pair of air outlets of the airflow distributor (3) is connected to the two air inlets of a cooling device (4). The cooling device (4) is provided with a nozzle in the middle, so that each cooling device (4) is connected in parallel within the airflow distributor (3).
2. The parallel cooling system for hot-dip galvanizing strips as described in claim 1, characterized in that: It also includes a buffer box (5), the bottom of which is a slope of 2° to 5° downward towards the air inlet and with the horizontal plane. The axis of the air duct (2) is obtuse. The buffer box (5) is connected in series on the air duct (2) and is located at the bend of the air duct (2). The air outlet of the air distributor (3) is equipped with a regulating valve and a barometer.
3. The method of using the parallel cooling system for hot-dip galvanizing unit strips as described in claim 1 or 2, characterized in that: Follow these steps in sequence: S1. Ventilation: The fan (1) draws in the outside air and pressurizes it before sending it into the airflow distributor (3) through the duct (2); S2. Cooling: The airflow distributor (3) ensures that the airflow rate entering each cooling device (4) is the same according to the number of parallel cooling devices (4), and ensures that the air pressure at the two air inlets of each cooling device (4) is the same, thereby ensuring that each cooling device (4) has the same cooling capacity. Each cooling device (4) sprays air onto the strip through nozzles to cool the strip.
4. The method of using the parallel cooling system for hot-dip galvanizing unit strips as described in claim 2, characterized in that: Follow these steps in sequence: S1. Ventilation: The fan (1) draws in the outside air and pressurizes it, then inputs it into the airflow distributor (3) through the air duct (2). The air is slowed down by the zigzag air duct (2) and the flow rate is reduced in the buffer box (5), so that the rainwater mixed in the air gathers and falls in the buffer box (5), and flows back to the air inlet through the inclined bottom of the buffer box (5) and is discharged to the outside, so as to avoid the quality of the strip steel from decreasing due to the mixing of rainwater. S2. Cooling: The airflow distributor (3) ensures that the airflow rate entering each cooling device (4) is the same according to the number of parallel cooling devices (4), and ensures that the air pressure at the two air inlets of each cooling device (4) is the same, thereby ensuring that each cooling device (4) has the same cooling capacity. Each cooling device (4) sprays air onto the strip through nozzles to cool the strip.