Automatic annealing and cooling method in glass container production
Through the multi-stage temperature control of the fully electric heating mesh belt annealing furnace, the problem of excessive temperature gradient during the annealing of the glass container is solved, and the uniform release of internal stress and quality improvement of the glass container is achieved, which significantly improves the service life of the glass container and productivity.
Patent Information
- Application Number
- CN202411618150.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-13
- Publication Date
- 2024-12-24
AI Technical Summary
The temperature control in the existing glass container annealing technology is not accurate enough, resulting in excessive temperature gradients in the glass container during the annealing process, which cannot effectively eliminate internal stress, affecting the quality and service life of the glass container.
The fully electric heating mesh belt annealing furnace is adopted to realize the glass container through multi-stage temperature control of the homogenized pre-annealing zone, important annealing cooling zone, indirect cooling zone, transition zone, rapid cooling zone, natural cooling zone and forced cooling zone. Continuous annealing and suitable cooling reduce equipment complexity and cost.
Achieve uniform release of stresses inside the glass container, improve the quality and safety of the glass container, reduce the risk of fracture, enhance the mechanical strength and heat shock resistance, simplify equipment maintenance, and reduce defects such as notches, cracks and bubbles The occurrence of
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Figure CN119176665A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of glass container annealing, and in particular relates to an automatic annealing and cooling method in glass container production. Background Art
[0002] Glass containers, such as glass bottles, beer bottles, juice bottles, soy sauce bottles, etc., need to be annealed and cooled during the production process. As we all know, glass containers are poor conductors of heat. During the temperature drop, there is a temperature difference between the outer and inner layers of the glass container. When there is a temperature difference, the hardening speed of the inner and outer layers of the glass container is different, so the glass container will have uneven internal stress. When the internal stress exceeds the ultimate strength of the glass container, it will cause the glass container to break. The heat treatment performed to minimize the possibility of this internal stress is called annealing.
[0003] Annealing is the process of using an appropriate temperature system to continuously cool the formed glass container strip to a processable temperature (about 70°C), while eliminating the residual stress in the glass container to an allowable range. The purpose of annealing is not only to eliminate the residual stress in the glass container strip, but also to eliminate the optical inhomogeneity caused by the glass container molding process and prevent changes in the internal structure of the glass container, thereby improving the quality of the glass container and ensuring the normal use of the glass.
[0004] Traditional glass container annealing processes mainly include furnace annealing, tunnel furnace annealing, etc. These methods can meet the annealing requirements to some extent, but they have certain limitations. In the existing glass container annealing technology, the temperature control is often not precise enough, resulting in excessive temperature gradients in the glass container during the annealing process, and the internal stress cannot be effectively eliminated, thereby affecting the quality of the glass container. The annealing process of the prior art is often divided into multiple independent stages, and there is a lack of effective transition between the stages, which causes the glass container to easily generate new stresses during the annealing process. In the annealing process of the prior art, it is impossible to achieve the balance of the internal and external temperatures of the glass container, so that the glass container still has large internal stresses after annealing, affecting its service life. The annealing equipment of the prior art is often more complicated, requiring the cooperation of multiple furnaces, heating elements and control systems, resulting in high equipment costs, large floor space and difficult maintenance. In the cooling process of the prior art, it is often impossible to achieve effective switching between rapid cooling and slow cooling, resulting in new stresses in the glass container during the cooling process.
[0005] In view of this, we propose a method for automatic annealing and cooling in glass container production by using a fully electric heating mesh belt annealing furnace, which can achieve precise temperature control, ensure the continuity of the annealing process, improve the annealing effect, reduce the complexity of the equipment, and achieve a suitable cooling speed, thereby improving the quality and safety of the glass containers. Summary of the invention
[0006] The present invention aims to solve the technical problem that the annealing temperature control of the glass container in the above-mentioned prior art is often not precise enough, resulting in excessive temperature gradient in the glass container during the annealing process, and the internal stress cannot be effectively eliminated, thereby affecting the quality of the glass container.
[0007] To achieve the above object, the present invention provides the following technical solutions:
[0008] A method for automatic annealing and cooling in glass container production, the method is implemented by a fully electric heating mesh belt annealing furnace, the fully electric heating mesh belt annealing furnace comprises a furnace body, a heating element and a control system, and the mesh belt annealing furnace is sequentially arranged from the entrance to the exit as a soaking pre-annealing zone, an important annealing cooling zone, an indirect cooling zone, a transition zone, a rapid cooling zone, a natural cooling zone and a forced cooling zone;
[0009] The method comprises the following steps:
[0010] S1. Soaking pre-annealing zone treatment: Place the glass container at the entrance of the all-electric heating mesh belt annealing furnace and enter the soaking pre-annealing zone. The furnace body starts to heat up and transfers heat to the glass container through the heating element. At this stage, the glass container gradually heats up so that its surface and internal temperatures gradually tend to be consistent.
[0011] S2. Treatment in the important annealing and cooling zone: After the glass container comes out of the soaking and pre-annealing zone, it enters the important annealing and cooling zone and is kept at a temperature of 480-550°C for 30-60 minutes;
[0012] In this area, the glass begins to cool down slowly, and the glass container enters the important annealing and cooling zone. The temperature in this area gradually decreases to release stress, so that the stress inside the glass can be further released.
[0013] S3. Indirect cooling zone treatment: Subsequently, the glass container enters the indirect cooling zone with a temperature range of 320-480°C and stays in this area for 20-40 minutes to allow the glass container to gradually lower its temperature at a slower rate to ensure that the internal stress of the glass continues to be released.
[0014] S4, transition zone treatment: the glass container continues to move forward and enters the transition zone with a temperature range of 280-320°C, and stays in the transition zone for 5-15 minutes to further reduce the temperature of the glass container in preparation for the subsequent rapid cooling; the purpose of the transition zone is to allow the glass to gradually adapt to a faster cooling rate.
[0015] S5. Rapid cooling zone treatment: The glass container enters the rapid cooling zone with a temperature range of 180-280°C. In this area, the glass container is cooled down rapidly by enhanced cooling to prevent new stress inside the glass due to excessive cooling.
[0016] S6. Natural cooling zone treatment: The glass container then enters the natural cooling zone with a temperature range of 150-180°C and stays in this area for 10-20 minutes. The glass container will naturally cool down slowly in the air in the natural cooling zone, further releasing internal stress.
[0017] S7, forced cooling zone treatment: the glass container leaves the natural cooling zone and enters the forced cooling zone with a temperature range of 70-150°C. In the forced cooling zone, air cooling is combined with enhanced cooling to quickly reduce the temperature of the glass container to room temperature, completing the annealing process;
[0018] S8. After the glass container passes through the forced cooling zone, it comes out of the annealing furnace outlet and cools to room temperature. The annealed glass container is taken out for quality inspection and subsequent inspection and packaging.
[0019] Preferably, the soaking pre-annealing zone includes soaking pre-annealing zone A and soaking pre-annealing zone B. The glass container enters soaking pre-annealing zone A and then soaking pre-annealing zone B. In soaking pre-annealing zone A and soaking pre-annealing zone B at a temperature of 550-650° C., the glass container is slowly heated in this zone by controlling the heating element to achieve the purpose of balancing the lateral temperature of the glass container. This step helps to reduce the temperature gradient inside the glass, thereby reducing internal stress.
[0020] The temperature of the soaking pre-annealing zone of 550-650°C is set slightly higher than the softening point of the glass container to ensure that the glass will not deform during the subsequent annealing process.
[0021] Preferably, in step S1, the glass container stays in the soaking pre-annealing zone A and the soaking pre-annealing zone B for 10-30 minutes respectively.
[0022] Preferably, in step S5, the glass container enters a rapid cooling zone and is maintained there for 10-30 minutes. In this zone, the temperature of the glass will drop rapidly. Enough rapid cooling time is reserved to prevent new stress from being generated inside the glass due to excessive cooling.
[0023] Preferably, in step S7, the glass container is cooled in the forced cooling zone with air cooling for 5-10 minutes.
[0024] Preferably, the inspection of the glass container in step S8 includes inspecting the glass container for defects such as notches, cracks, black spots and bubbles.
[0025] Compared with the prior art, the technical effects and advantages of the present invention are:
[0026] The automatic annealing and cooling method in the production of glass containers achieves uniform release of internal stress of the glass container by precisely controlling the temperature and cooling rate of different areas. By processing in multiple specially designed temperature zones, including a soaking pre-annealing zone, an important annealing cooling zone, an indirect cooling zone, a transition zone, a rapid cooling zone, a natural cooling zone, and a forced cooling zone, the temperature gradient and internal stress inside the glass container can be effectively reduced, and the stress concentration caused by uneven temperature can be reduced, thereby significantly improving the overall quality of the glass container.
[0027] By controlling the temperature change during the annealing process, the risk of glass containers breaking during use can be reduced, and the durability and service life of the product can be improved. The automated annealing cooling process can improve production efficiency, reduce manual intervention, and ensure the stability and repeatability of the annealing process. By gradually cooling, the present invention helps to optimize the internal structure of the glass, reduce residual stress, and further enhance the mechanical strength and thermal shock resistance of the glass container.
[0028] The present invention strictly controls each stage in the annealing process, which helps to reduce defects such as gaps, cracks, black spots and bubbles in glass containers, and improves the appearance quality of the product. The fully electric heating annealing furnace is more environmentally friendly than the traditional fuel heating furnace, reduces exhaust gas and dust emissions, and is beneficial to environmental protection. The use of electric heating can achieve more precise temperature control, ensuring that the temperature of each area is maintained at the optimal state, thereby ensuring the annealing effect. The fully electric heating mesh belt annealing furnace has a simple structure, is easy to maintain, and is easy to operate, which is convenient for daily production management. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Figure 1 It is a structural schematic diagram of the present invention.
[0030] In the figure: 100, all-electric heating mesh belt annealing furnace; 1, soaking pre-annealing zone; 2, important annealing cooling zone; 3, indirect cooling zone; 4, transition zone; 5, rapid cooling zone; 6, natural cooling zone; 7, forced cooling zone. DETAILED DESCRIPTION
[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0032] The following is combined with Figure 1 To further explain this application in detail,
[0033] The present application embodiment discloses a method for automatic annealing and cooling in glass container production, comprising the following steps:
[0034] S1, soaking pre-annealing zone treatment: place the glass container at the entrance of the annealing furnace and enter the soaking pre-annealing zone 1, which includes the soaking pre-annealing zone 1A and the soaking pre-annealing zone 1B. The glass container enters the soaking pre-annealing zone 1A and then enters the soaking pre-annealing zone 1B. The glass container stays in the soaking pre-annealing zone 1A and the soaking pre-annealing zone 1B at a temperature of 550-650°C for 10-30 minutes respectively. The furnace body starts to heat up, and the heat is transferred to the glass container through the heating element, so that the glass container slowly heats up in this area. At this stage, the glass container gradually heats up, so that the surface and internal temperatures gradually tend to be consistent, so as to achieve the purpose of balancing the lateral temperature of the glass container. This step helps to reduce the temperature gradient inside the glass, thereby reducing the internal stress. The temperature of the 550-650℃ soaking pre-annealing zone 1 is set slightly higher than the softening point of the glass container to ensure that the glass will not be deformed during the subsequent annealing process;
[0035] S2. Treatment in the important annealing and cooling zone: After the glass container comes out of the soaking pre-annealing zone 1, it enters the important annealing and cooling zone 2 and is kept at a temperature of 480-550°C for 30-60 minutes. In this zone, the glass begins to cool down slowly. The glass container enters the important annealing and cooling zone 2, and the temperature in this zone gradually decreases to release stress, so that the stress inside the glass can be further released.
[0036] S3, indirect cooling zone treatment: Subsequently, the glass container enters the indirect cooling zone 3 with a temperature range of 320-480°C, and stays in this area for 20-40 minutes, so that the glass container gradually lowers the temperature at a slower rate; to ensure that the internal stress of the glass continues to be released.
[0037] S4, transition zone 4 treatment: the glass container continues to move forward and enters transition zone 4 with a temperature range of 280-320°C, and stays in transition zone 4 for 5-15 minutes to further reduce the temperature of the glass container in preparation for the subsequent rapid cooling; the purpose of transition zone 4 is to allow the glass to gradually adapt to a faster cooling rate.
[0038] S5, rapid cooling zone treatment: the glass container enters the rapid cooling zone 5 with a temperature range of 180-280°C. In this zone, the glass container is cooled rapidly by enhanced cooling. To prevent new stress from being generated inside the glass due to excessive cooling, the glass container enters the rapid cooling zone 5 and remains there for 10-30 minutes. In this zone, the temperature of the glass will drop rapidly. Enough rapid cooling time is reserved to prevent new stress from being generated inside the glass due to excessive cooling.
[0039] S6, natural cooling zone treatment: The glass container then enters the natural cooling zone 6 with a temperature range of 150-180°C and stays in this area for 10-20 minutes. The glass container will naturally and slowly cool down in the air in the natural cooling zone 6 to further release the internal stress.
[0040] S7, forced cooling zone treatment: the glass container leaves the natural cooling zone 6 and enters the forced cooling zone 7 with a temperature range of 70-150°C. In the forced cooling zone 7, air cooling is combined with enhanced cooling for 5-10 minutes to rapidly reduce the temperature of the glass container to room temperature, thus completing the annealing process;
[0041] S8, after the glass container passes through the forced cooling zone 7, it comes out of the annealing furnace outlet and cools to room temperature. The annealed glass container is taken out for quality inspection, and subsequent inspection and packaging are carried out. The inspection of the glass container includes the inspection of the glass container for notches, cracks, black spots and bubble defects.
[0042] The various steps of automatic annealing and cooling in the production of the glass container are carried out in a fully electric heating mesh belt annealing furnace 100, which includes a furnace body, a heating element and a control system. The mesh belt annealing furnace is sequentially arranged from the entrance to the exit as a soaking pre-annealing zone 1, an important annealing and cooling zone 2, an indirect cooling zone 3, a transition zone 4, a rapid cooling zone 5, a natural cooling zone 6 and a forced cooling zone 7.
[0043] In the automatic annealing and cooling method for glass container production, the glass container is provided with uniform heat by heating elements in the soaking pre-annealing zone 1A and the soaking pre-annealing zone 1B, so that the container is gradually heated to 550-650°C. In this process, the surface and internal temperatures of the glass container gradually tend to be consistent, the lateral temperature is balanced, and the internal temperature gradient is reduced, thereby effectively reducing the internal stress. The working principle of this step is to ensure the temperature uniformity of the glass container in the entire area by precisely controlling the heating elements. It helps to improve the overall quality of the glass container, reduce the stress concentration caused by uneven temperature, and reduce the risk of glass containers breaking during use.
[0044] After leaving the soaking pre-annealing zone 1, the glass container enters the important annealing cooling zone 2 with a temperature range of 480-550℃. In this zone, the glass container begins to slowly cool down to release internal stress. By controlling the temperature to gradually decrease, the internal stress of the glass is ensured to be released uniformly. This helps to optimize the internal structure of the glass, reduce residual stress, and improve the durability and service life of the glass container.
[0045] The glass container continues to cool down in the indirect cooling zone 3 at 320-480℃ and the transition zone 4 at 280-320℃. The indirect cooling zone 3 cools the glass container at a slower rate to ensure that stress continues to be released; the transition zone 4 allows the glass container to gradually adapt to a faster cooling rate in preparation for rapid cooling. This gradual cooling method helps to avoid new stress in the glass container during rapid cooling, maintain the integrity of the glass, and avoid cracks and deformation.
[0046] Rapid cooling zone 5, natural cooling zone 6 and forced cooling zone 7 treatment: The glass container is rapidly cooled in the rapid cooling zone 5 at 180-280℃, and then enters the natural cooling zone 6 at 150-180℃ and the forced cooling zone 7 at 70-150℃, where it is cooled to room temperature by means of air cooling and other means. The rapid cooling zone 5 can effectively reduce the temperature of the glass container, while the natural cooling zone 6 and forced cooling zone 7 help to further release the internal stress, ensuring that the glass container reaches the best use state after leaving the furnace.
[0047] In summary, different electric heating and cooling systems are used to achieve reasonable cooling and achieve the purpose of good annealing. This automatic annealing and cooling method can achieve uniform release of internal stress of glass containers by precisely controlling the temperature and cooling rate of each area, thereby improving the quality and safety of glass containers.
[0048] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A method for automatic annealing and cooling in glass container production, characterized in that: The method is implemented by an all-electric heating mesh belt annealing furnace, which includes a furnace body, a heating element and a control system. The mesh belt annealing furnace is sequentially arranged from the entrance to the exit as a soaking pre-annealing zone, an important annealing cooling zone, an indirect cooling zone, a transition zone, a rapid cooling zone, a natural cooling zone and a forced cooling zone; The method comprises the following steps: S1. Soaking pre-annealing zone treatment: Place the glass container at the entrance of the all-electric heating mesh belt annealing furnace and enter the soaking pre-annealing zone. The furnace body starts to heat up and transfers heat to the glass container through the heating element. At this stage, the glass container gradually heats up so that its surface and internal temperatures gradually tend to be consistent. S2. Treatment in the important annealing and cooling zone: After the glass container comes out of the soaking and pre-annealing zone, it enters the important annealing and cooling zone and is kept at a temperature of 480-550°C for 30-60 minutes; S3, indirect cooling zone treatment: Subsequently, the glass container enters the indirect cooling zone with a temperature range of 320-480°C, and stays in this zone for 20-40 minutes, so that the glass container gradually lowers the temperature at a slower rate; S4, transition zone treatment: the glass container continues to move forward and enters the transition zone with a temperature range of 280-320°C, and stays in the transition zone for 5-15 minutes to further reduce the temperature of the glass container in preparation for the subsequent rapid cooling; S5, rapid cooling zone treatment: the glass container enters the rapid cooling zone with a temperature range of 180-280°C, where the glass container is rapidly cooled by enhanced cooling; S6, natural cooling zone treatment: the glass container then enters a natural cooling zone with a temperature range of 150-180°C and remains in this zone for 10-20 minutes; S7, forced cooling zone treatment: the glass container leaves the natural cooling zone and enters the forced cooling zone with a temperature range of 70-150°C. In the forced cooling zone, air cooling is combined with enhanced cooling to quickly reduce the temperature of the glass container to room temperature, completing the annealing process; S8. After the glass container passes through the forced cooling zone, it comes out of the annealing furnace outlet and cools to room temperature. The annealed glass container is taken out for quality inspection and subsequent inspection and packaging.
2. The method for automatic annealing and cooling in glass container production according to claim 1, characterized in that: The soaking pre-annealing zone includes soaking pre-annealing zone A and soaking pre-annealing zone B. The glass container enters soaking pre-annealing zone A and then enters soaking pre-annealing zone B. In soaking pre-annealing zone A and soaking pre-annealing zone B with a temperature of 550-650°C, the glass container is slowly heated in this zone by controlling the heating element.
3. The method for automatic annealing and cooling in glass container production according to claim 2, characterized in that: In step S1, the glass container stays in the soaking pre-annealing zone A and the soaking pre-annealing zone B for 10-30 minutes respectively.
4. The method for automatic annealing and cooling in glass container production according to claim 1, characterized in that: In step S5, the glass container enters a rapid cooling zone and is kept there for 10-30 minutes.
5. The method for automatic annealing and cooling in glass container production according to claim 1, characterized in that: In step S7, the glass container is cooled in the forced cooling zone with air cooling for 5-10 minutes.
6. The method for automatic annealing and cooling in glass container production according to claim 1, characterized in that: The inspection of the glass container in step S8 includes inspecting the glass container for defects such as notches, cracks, black spots and bubbles.