Hot air drying system for strip coating production line
By using closed-loop control of downwind knives and upwind knives, temperature sensors and humidity sensors in the hot air drying system of the strip coating production line, the problems of excessive temperature and energy waste caused by the continuous action of hot air in traditional systems are solved, and more efficient drying and energy utilization are achieved.
Patent Information
- Application Number
- CN202420805284.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-18
- Publication Date
- 2025-03-18
- Estimated Expiration
- 2034-04-18
AI Technical Summary
Traditional hot air drying systems have problems such as the continuous action of hot air in the strip coating production line, resulting in excessive local temperature, low drying efficiency, waste of energy and inaccurate temperature control.
A hot air drying system with downwind and upwind knives was designed, and closed-loop control was adopted for temperature sensors and humidity sensors to realize feedback control of the hot air process temperature and humidity, and direct exhaust of hot air when the production line is shut down to ensure heat recovery and energy conservation.
Through closed-loop control of the temperature and humidity of the hot air process, the curing quality and production efficiency of the strip surface coating film are improved, energy is saved, and the problem of waiting for the hot air system to start during frequent shutdowns is solved.
Smart Images
Figure CN222625239U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of strip coating production equipment, in particular to a hot air drying system for a strip coating production line. Background Art
[0002] Strip coating production lines usually consist of roller coating, hot air drying and other processes. For traditional hot air drying, hot air passes through wind knives and directly acts on the upper and lower surfaces of the strip. The drying area is usually made into a closed drying furnace to prevent heat loss and heat insulation. However, there are the following shortcomings in use:
[0003] 1. Since the drying furnace is closed, the hot air evaporates the moisture in the coating on the surface of the strip, causing the air humidity in the drying furnace to increase, which is not conducive to the curing of the coating film on the surface of the strip.
[0004] 2. The hot air blower is linked with the production line. When the production line stops, the hot air system also stops. If the hot air system does not stop, the hot air will continue to act on the strip, causing the local temperature to be too high, causing the strip to deform and produce defective products. However, when the production line is restarted, it is usually necessary to wait until the hot air temperature reaches the specified value before the strip can be operated. For strip coating production lines that frequently stop, production efficiency will be seriously reduced.
[0005] 3. The hot air blower usually draws air directly from the environment, heats the air to the set temperature and then directly acts on the strip. Although the air drying box is relatively closed, the heat will still overflow. The lack of energy recovery measures will cause a certain amount of energy waste.
[0006] 4. The hot air system usually uses the detected temperature of the hot air blower's own outlet as the closed-loop condition, while the hot air temperature actually acting on the strip is closely related to the pipeline length, insulation measures, etc. Therefore, there is a lack of temperature detection closed-loop control at the hot air system terminal, and the temperature control is inaccurate. Summary of the invention
[0007] In order to overcome the deficiencies of the prior art, the utility model aims to provide a hot air drying system for a strip coating production line to improve production efficiency and save energy.
[0008] To achieve the above-mentioned purpose of the invention, the lower air knife and the upper air knife of the utility model are placed in an air drying box; the air inlet connected to the air drying box is connected to the upper air knife via an industrial blower, three-way distributor four, three-way distributor one, a filter, an industrial hot air blower, a throttle valve two, and a three-way distributor three in sequence; the air inlet is connected to the lower air knife via an industrial blower, three-way distributor four, three-way distributor one, a filter, an industrial hot air blower, a throttle valve one, and a three-way distributor two in sequence.
[0009] Furthermore, the upper air knife and the lower air knife are respectively provided with a second temperature sensor and a first temperature sensor.
[0010] Furthermore, a humidity sensor is provided in the air drying box.
[0011] Furthermore, the air inlet, the industrial blower, the three-way distributor four, the three-way distributor one, the filter, and the industrial hot air blower are connected in series.
[0012] Furthermore, the circuit composed of the throttle valve 2, the three-way distributor, and the upper air knife is connected in parallel with the circuit composed of the throttle valve 1, the two three-way distributor, and the lower air knife.
[0013] Furthermore, the closed-loop control circuit of the hot air process temperature of the lower air knife of the hot air drying system is as follows: the air flow passes through the air inlet, the industrial blower, the a distribution port of the four three-way distributors, the c distribution port of the four three-way distributors, the a distribution port of the first three-way distributor, the b distribution port of the first three-way distributor, the filter, the industrial hot air blower, the throttle valve 1, the a distribution port of the second three-way distributor, the c distribution port of the second three-way distributor, the lower air knife acts on The lower surface of the strip; the upper air knife hot air process temperature closed-loop control circuit is: the air flow passes through the air inlet, industrial blower, a distribution port of three-way distributor four, c distribution port of three-way distributor four, a distribution port of three-way distributor one, b distribution port of three-way distributor one, filter, industrial hot air blower, throttle valve two, a distribution port of three-way distributor three, c distribution port of three-way distributor three, and upper air knife to act on the upper surface of the strip.
[0014] Furthermore, the humidity closed-loop control circuit in the air drying box of the hot air drying system is: the air with high humidity in the air drying box is discharged through the air inlet, the industrial blower, and the b distribution port of the three-way distributor four; the air flow control circuit of the industrial hot air blower acting on the lower air knife is: the air acts on the lower surface of the strip through the c distribution port of the three-way distributor one, the b distribution port of the three-way distributor one, the filter, the industrial hot air blower, the throttle valve one, the a distribution port of the three-way distributor two, the c distribution port of the three-way distributor two, and the lower air knife; the air flow control circuit of the industrial hot air blower acting on the upper air knife is: the air acts on the upper surface of the strip through the c distribution port of the three-way distributor one, the b distribution port of the three-way distributor one, the filter, the industrial hot air blower, the throttle valve two, the a distribution port of the three-way distributor three, the c distribution port of the three-way distributor three, and the upper air knife.
[0015] Furthermore, the hot air direct exhaust control circuit of the lower wind knife when the production line of the hot air drying system is shut down is: the air flow passes through the air inlet, the industrial blower, the a distribution port of the three-way distributor four, the c distribution port of the three-way distributor four, the a distribution port of the three-way distributor one, the b distribution port of the three-way distributor one, the filter, the industrial hot air blower, the throttle valve one, the a distribution port of the three-way distributor two, and the b distribution port of the three-way distributor two to directly exhaust the hot air. Emptying; When the production line of the hot air drying system is shut down, the control circuit for direct emptying of the upper knife hot air is as follows: the airflow passes through the air inlet, industrial blower, the a distribution port of three-way distributor four, the c distribution port of three-way distributor four, the a distribution port of three-way distributor one, the b distribution port of three-way distributor one, the filter, industrial hot air blower, throttle valve two, the a distribution port of three-way distributor three, and the b distribution port of three-way distributor three to directly empty the hot air.
[0016] Furthermore, the industrial blower, the industrial hot air blower, the three-way distributor 1, the three-way distributor 2, the three-way distributor 3, the four-way distributor 4, the throttle valve 1 and the throttle valve 2 are connected to a control system.
[0017] Compared with the prior art, the utility model has a hot air process temperature feedback closed-loop control system to ensure that the terminal hot air temperature meets the process requirements; at the same time, a humidity feedback closed-loop control of the air drying box is provided to effectively improve the coating quality of the coating film on the surface of the strip; it also has a heat recovery function, which saves energy, improves heat utilization efficiency, and solves the problem of starting up and waiting for the hot air system of the strip coating production line with short-term frequent shutdowns, so as to adapt to more complex production conditions and improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 It is a simplified diagram of the system structure of the utility model. DETAILED DESCRIPTION
[0019] like Figure 1As shown, the lower air knife 6 and the upper air knife 13 of the utility model are placed in the air drying box 9; the air inlet 12 connected to the air drying box 9 is connected to the upper air knife 13 via the industrial blower 16, the three-way distributor four 17, the three-way distributor one 1, the filter 2, the industrial hot air blower 3, the throttle valve two 15, and the three-way distributor three 14 in sequence; the air inlet 12 is connected to the lower air knife 6 via the industrial blower 16, the three-way distributor four 17, the three-way distributor one 1, the filter 2, the industrial hot air blower 3, the throttle valve one 4, and the three-way distributor two 5 in sequence; the upper air knife 13 and the lower air knife 6 are respectively provided with a temperature sensor two 11 and a temperature sensor one 7; a humidity sensor 10 is provided in the air drying box 9. The air inlet 12, industrial blower 16, three-way distributor 4 17, three-way distributor 1 1, filter 2, industrial hot air blower 3 are connected in series; the circuit composed of throttle valve 2 15, three-way distributor 3 14, and upper air knife 13 is connected in parallel with the circuit composed of throttle valve 1 4, three-way distributor 2 5, and lower air knife 6. The industrial blower 16, industrial hot air blower 3, three-way distributor 1 1, three-way distributor 2 5, three-way distributor 3 14, three-way distributor 4 17, throttle valve 1 4, and throttle valve 2 15 are connected to the control system.
[0020] The utility model realizes the closed-loop control circuit of the hot air process temperature of the lower air knife 6 as follows: the air flow passes through the air inlet 12, the industrial blower 16, the a distribution port of the three-way distributor 17, the c distribution port of the three-way distributor 17, the a distribution port of the three-way distributor 1, the b distribution port of the three-way distributor 1, the filter 2, the industrial hot air blower 3, the throttle valve 14, the a distribution port of the three-way distributor 25, the c distribution port of the three-way distributor 25, and the lower air knife 6 acting on the lower surface of the strip 8 in sequence. The closed-loop control circuit of the hot air process temperature of the upper air knife 13 is: the air flow passes through the air inlet 12, the industrial blower 16, the a distribution port of the three-way distributor 17, the c distribution port of the three-way distributor 17, the a distribution port of the three-way distributor 11, the b distribution port of the three-way distributor 11, the filter 2, the industrial hot air blower 3, the throttle valve 2 15, the a distribution port of the three-way distributor 14, the c distribution port of the three-way distributor 14, and the upper air knife 13 to act on the upper surface of the strip 8. The industrial blower 16 of the utility model can directly inhale air from the air inlet 12 in the air drying box 9. As the temperature in the air drying box 9 increases, the temperature of the hot air system intake increases, and the heat required to heat the air to the specified temperature gradually decreases, and finally tends to be stable, reaching 30-150 degrees. The system can match the corresponding temperature value according to the coating characteristics of the strip 8. The method can improve energy utilization through a closed-loop control circuit of the hot air process temperature, and while achieving energy conservation, it can also prevent the environment around the air drying box 9 from being too high to ensure safe production.
[0021] For the coating production line, the paint contains some moisture. As the hot air dries, the moisture in the coating on the surface of the strip 8 evaporates, causing the air humidity in the air drying box 9 to increase. When the humid hot air acts on the surface of the strip 8, the drying effect is not ideal. At this time, the humidity sensor 10 in the air drying box 9 detects the air humidity in a timely manner. When the humidity reaches the set value, the three-way distributor four 17 and the three-way distributor one 1 will be activated to discharge the air with high humidity in the air drying box 9 through the air inlet 12, the industrial blower 16, and the b distribution port of the three-way distributor four 17; at the same time, the airflow control circuit of the industrial hot air blower 3 acting on the lower air knife 6 becomes: the air passes through the c distribution port of the three-way distributor one 1, the b distribution port of the three-way distributor one 1, the filter 2, the industrial hot air blower 3, The throttle valve 1 4, the a-distribution port of the three-way distributor 2 5, the c-distribution port of the three-way distributor 2 5, and the lower air knife 6 act on the lower surface of the strip 8; the airflow control loop of the industrial hot air blower 3 acting on the upper air knife 13 becomes: the air acts on the upper surface of the strip 8 through the c-distribution port of the three-way distributor 1 1, the b-distribution port of the three-way distributor 1 1, the filter 2, the industrial hot air blower 3, the throttle valve 2 15, the a-distribution port of the three-way distributor 3 14, the c-distribution port of the three-way distributor 3 14, and the upper air knife 13. Under the dual effects of extracting the air with high humidity (humidity greater than 85%) in the air drying box 9 and injecting fresh hot air, the air humidity in the air drying box 9 is quickly restored to within 85%, thereby realizing the closed-loop control of the humidity of the air drying box 9 and improving the coating quality of the surface of the strip 8.
[0022] When the coating production line stops due to an abnormal situation, the strip 8 stops moving. If the hot air system continues to dry at this time, the local temperature of the strip 8 will rise, and in severe cases, the strip 8 will be scrapped. If the hot air system stops, it will be necessary to wait until the hot air temperature reaches the set value when it is restarted. Therefore, under frequent shutdown conditions, the effectiveness efficiency is greatly affected. In the utility model, when the production line is shut down, the b distribution port of the three-way distributor 2 5 of the lower air knife 6 branch and the b distribution port of the three-way distributor 3 14 of the upper air knife 13 branch will immediately operate to directly discharge the hot air in the air drying box 9, thereby avoiding the continuous direct action of the hot air on the strip 8. When the production line resumes operation, the c distribution port of the three-way distributor 2 5 of the lower air knife 6 branch and the c distribution port of the three-way distributor 3 14 of the upper air knife 13 branch will immediately operate, and the production line will start directly. By canceling the heating waiting time when the hot air system is started, the production efficiency can be greatly improved for the strip coating production line that needs to be shut down frequently for a short time. The control circuit for direct emptying of the hot air of the lower air knife 6 when the production line of the hot air drying system of the utility model is shut down is: the airflow passes through the air inlet 12, the industrial blower 16, the a distribution port of the three-way distributor 4 17, the c distribution port of the three-way distributor 4 17, the a distribution port of the three-way distributor 1, the b distribution port of the three-way distributor 1, the filter 2, the industrial hot air blower 3, the throttle valve 1 4, the a distribution port of the three-way distributor 2 5, and the b distribution port of the three-way distributor 2 5 to directly discharge the hot air. ; When the production line of the hot air drying system is shut down, the control circuit for directly exhausting the hot air from the upper air knife 13 is as follows: the airflow passes through the air inlet 12, the industrial blower 16, the a distribution port of the three-way distributor 4 17, the c distribution port of the three-way distributor 4 17, the a distribution port of the three-way distributor 1, the b distribution port of the three-way distributor 1, the filter 2, the industrial hot air blower 3, the throttle valve 2 15, the a distribution port of the three-way distributor 3 14, and the b distribution port of the three-way distributor 3 14 to directly exhaust the hot air. After the production line is started, the hot air drying system returns to the hot air process temperature closed-loop control circuit of the lower air knife 6 and the upper air knife 13. This enables the system to have a heat recovery function, save energy, and improve heat utilization efficiency.
[0023] In practical applications, the utility model can provide sufficient drying effect for the strip coating production line by connecting multiple sets of hot air systems in parallel.
Claims
1. A hot air drying system for a strip coating production line, characterized in that: The lower air knife (6) and the upper air knife (13) are placed in the air drying box (9); the air inlet (12) connected to the air drying box (9) is connected to the upper air knife (13) via the industrial blower (16), three-way distributor four (17), three-way distributor one (1), filter (2), industrial hot air blower (3), throttle valve two (15), and three-way distributor three (14) in sequence; the air inlet (12) is connected to the lower air knife (6) via the industrial blower (16), three-way distributor four (17), three-way distributor one (1), filter (2), industrial hot air blower (3), throttle valve one (4), and three-way distributor two (5) in sequence.
2. A hot air drying system for a strip coating production line according to claim 1, characterized in that: The upper air knife (13) and the lower air knife (6) are provided with a second temperature sensor (11) and a first temperature sensor (7) respectively.
3. The hot air drying system for a strip coating production line according to claim 1, characterized in that: A humidity sensor (10) is provided in the air drying box (9).
4. The hot air drying system for a strip coating production line according to claim 1, characterized in that: The air inlet (12), the industrial blower (16), the three-way distributor four (17), the three-way distributor one (1), the filter (2), and the industrial hot air blower (3) are connected together in series.
5. The hot air drying system for a strip coating production line according to claim 1, characterized in that: The circuit formed by the throttle valve 2 (15), the three-way distributor 3 (14) and the upper air knife (13) is connected in parallel with the circuit formed by the throttle valve 1 (4), the three-way distributor 2 (5) and the lower air knife (6).
6. The hot air drying system for a strip coating production line according to claim 1, characterized in that: The closed-loop control circuit of the hot air process temperature of the lower air knife (6) of the hot air drying system is as follows: the air flow passes through the air inlet (12), the industrial blower (16), the a distribution port of the three-way distributor four (17), the c distribution port of the three-way distributor four (17), the a distribution port of the three-way distributor one (1), the b distribution port of the three-way distributor one (1), the filter (2), the industrial hot air blower (3), the throttle valve one (4), the a distribution port of the three-way distributor two (5), the c distribution port of the three-way distributor two (5), and the lower air knife (6) to act on the strip (8) in the following manner: The upper air knife (13) hot air process temperature closed-loop control circuit is as follows: the air flow passes through the air inlet (12), the industrial blower (16), the a distribution port of the three-way distributor four (17), the c distribution port of the three-way distributor four (17), the a distribution port of the three-way distributor one (1), the b distribution port of the three-way distributor one (1), the filter (2), the industrial hot air blower (3), the throttle valve two (15), the a distribution port of the three-way distributor three (14), the c distribution port of the three-way distributor three (14), and the upper air knife (13) to act on the upper surface of the strip (8).
7. The hot air drying system for a strip coating production line according to claim 1, characterized in that: The humidity closed-loop control circuit in the air drying box (9) of the hot air drying system is as follows: the air with high humidity in the air drying box (9) is discharged through the air inlet (12), the industrial blower (16), and the b distribution port of the three-way distributor (17); the airflow control circuit of the industrial hot air blower (3) acting on the lower air knife (6) is as follows: the air is discharged through the c distribution port of the three-way distributor (1), the b distribution port of the three-way distributor (1), the filter (2), the industrial hot air blower (3), the throttle valve (1) and the a distribution port of the three-way distributor (5). The air flow control circuit of the industrial hot air blower (3) acting on the upper air knife (13) is as follows: the air passes through the c distribution port of the three-way distributor (1), the b distribution port of the three-way distributor (1), the filter (2), the industrial hot air blower (3), the throttle valve (2), the a distribution port of the three-way distributor (14), the c distribution port of the three-way distributor (14), and the upper air knife (13) to act on the upper surface of the strip (8).
8. The hot air drying system for a strip coating production line according to claim 1, characterized in that: The hot air direct exhaust control circuit of the lower wind knife (6) of the hot air drying system when the production line is shut down is as follows: the airflow passes through the air inlet (12), the industrial blower (16), the a distribution port of the three-way distributor four (17), the c distribution port of the three-way distributor four (17), the a distribution port of the three-way distributor one (1), the b distribution port of the three-way distributor one (1), the filter (2), the industrial hot air blower (3), the throttle valve one (4), the a distribution port of the three-way distributor two (5), and the b distribution port of the three-way distributor two (5) in sequence to directly exhaust the hot air; The control circuit for directly exhausting the hot air from the upper air knife (13) when the production line of the air drying system is shut down is as follows: the airflow passes through the air inlet (12), the industrial blower (16), the a distribution port of the three-way distributor four (17), the c distribution port of the three-way distributor four (17), the a distribution port of the three-way distributor one (1), the b distribution port of the three-way distributor one (1), the filter (2), the industrial hot air blower (3), the throttle valve two (15), the a distribution port of the three-way distributor three (14), and the b distribution port of the three-way distributor three (14) in sequence to directly exhaust the hot air.
9. The hot air drying system for a strip coating production line according to claim 1, characterized in that: The industrial blower (16), the industrial hot air blower (3), the three-way distributor 1 (1), the three-way distributor 2 (5), the three-way distributor 3 (14), the three-way distributor 4 (17), the throttle valve 1 (4), and the throttle valve 2 (15) are connected to a control system.