A silicon nitride rotor structure based on speed and immersion depth cooperative control
Patent Information
- Application Number
- CN202522488375.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-24
- Publication Date
- 2026-10-09
- Estimated Expiration
- 2035-11-24
AI Technical Summary
[0003]现有技术中，除气转子多采用石墨材质，配套在线除气箱使用时存在显著缺陷：一是石墨转子耐高温氧化性能差，在铝熔体温度 650℃-750℃的工况下，与空气接触部位易发生碳氧化反应（生成 CO、CO2），导致转子轴径逐渐减小，寿命仅 1 个月左右，需频繁更换，不仅增加工人劳动强度，还易中断连续生产；二是石墨材质强度低、耐热冲击性差，限制了转子转速提升（常规转速 200r/min-400r/min），而转速不足会导致惰性气体气泡粒径偏大、分散度低，除气效率仅 50%-60%，难以满足高精铝材对熔体纯净度的要求；三是现有装置缺乏对转子浸入深度的精准控制，浸入过浅时气泡易过早逸出，与熔体接触时间短，氢气吸附不充分；浸入过深则会增大熔体阻力，且气泡上升路径过长可能导致部分氢气重新溶解，进一步降低除氢质量
本实用新型示例的基于转速与浸入深度协同控制的氮化硅转子结构，在氮化硅材质的转子上依次设置挡盘和双层导流叶轮，不仅提高了转子的使用寿命，还能够将气柜输送过来的精炼气体充分打散并分布到铝熔体的所有位置，在实现高效除氢目的的同时减少铝液飞溅，提高除气效率，并降低了维护频率，使用方便。
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Figure CN224832790U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of aluminum and aluminum alloy melt refining and degassing technology, specifically a silicon nitride rotor structure based on the coordinated control of rotation speed and immersion depth. Background Technology
[0002] In aluminum and aluminum alloy casting production, hydrogen in the molten metal is the main cause of defects such as porosity and looseness in castings. This is especially true for downstream products such as can body blanks, which require multiple thinning processes (final thickness ≤0.3mm), and have extremely low tolerance for hydrogen content in the molten metal (≤30ppm for can body blanks, zero for can lid blanks). Therefore, efficient degassing is a core element in ensuring product quality. Currently, the industry commonly uses the "floating method" for degassing, which involves using a rotating rotor to break inert gas into tiny bubbles. The hydrogen partial pressure difference between the bubbles and the molten metal is used to adsorb and carry away the hydrogen. The rotor, as the core component of the degassing process, directly determines the degassing efficiency.
[0003] In existing technologies, degassing rotors are mostly made of graphite, which has significant drawbacks when used with online degassing boxes: First, graphite rotors have poor resistance to high-temperature oxidation. Under conditions where the aluminum melt temperature is 650℃-750℃, carbon oxidation (generating CO and CO2) easily occurs at the parts in contact with air, causing the rotor shaft diameter to gradually decrease and its lifespan to only about one month, requiring frequent replacement. This not only increases the labor intensity of workers but also easily interrupts continuous production. Second, graphite has low strength and poor thermal shock resistance, which limits the increase in rotor speed (the conventional speed is 200r / min-400r / min). Insufficient speed will result in larger particle size and lower dispersion of inert gas bubbles, with a degassing efficiency of only 50%-60%, which is difficult to meet the purity requirements of high-precision aluminum materials. Third, existing devices lack precise control over the rotor immersion depth. If the immersion is too shallow, the bubbles are prone to escape prematurely, resulting in a short contact time with the melt and insufficient hydrogen adsorption. If the immersion is too deep, it will increase the melt resistance, and the excessively long bubble rising path may cause some hydrogen to redissolve, further reducing the hydrogen removal quality.
[0004] In addition, the inert gas supply of traditional degassing devices is mostly at a fixed flow rate, which cannot be dynamically adjusted according to changes in rotor speed and immersion depth. When the speed increases, the fixed flow rate of gas is difficult to be fully dispersed, resulting in poor bubble quantity and dispersion effect, which restricts the improvement of degassing efficiency. Utility Model Content
[0005] The technical problem to be solved by this utility model is to overcome the existing defects and provide a silicon nitride rotor structure based on the coordinated control of rotation speed and immersion depth. The rotor is made of silicon nitride material and baffles and double-layer guide impellers are arranged in sequence. This not only improves the service life of the rotor, but also can fully disperse and distribute the refining gas delivered from the gas holder to all parts of the aluminum melt. While achieving efficient hydrogen removal, it reduces aluminum liquid splashing, improves degassing efficiency, and reduces maintenance frequency. It is easy to use and can effectively solve the problems in the background technology.
[0006] To achieve the above objectives, this utility model provides the following technical solution: a silicon nitride rotor structure based on coordinated control of rotation speed and immersion depth, comprising a rotor, the rotor being a hollow silicon carbide material, an impeller mounted at the bottom of the rotor being a double-layer guide impeller, and a flange mounted at the top of the rotor, and a baffle plate for protecting the flange being provided on the upper side of the rotor.
[0007] As a preferred embodiment of this utility model, the upper side of the rotor is provided with an external thread groove, the bottom of the flange is provided with an installation sleeve, the inner side of the installation sleeve is provided with an internal thread groove, and the rotor is threadedly connected to the installation sleeve.
[0008] As a preferred embodiment of this utility model, the rotor has an inner diameter of 50mm and an outer diameter of 80mm.
[0009] As a preferred embodiment of this utility model, the diameter of the baffle is 180mm.
[0010] As a preferred technical solution of this utility model, the rotor is threadedly connected to the impeller, and the impeller has a through hole that penetrates its upper and lower surfaces and communicates with the inside of the rotor.
[0011] As a preferred embodiment of the present invention, the impeller includes an upper disk and a lower disk, and guide plates are evenly arranged between the upper disk and the lower disk, and the upper disk is installed at the bottom of the rotor.
[0012] Compared with the prior art, the beneficial effects of this utility model are: This utility model illustrates a silicon nitride rotor structure based on coordinated control of rotational speed and immersion depth. The rotor, made of silicon nitride material, is equipped with baffles and double-layer guide impellers in sequence. This not only improves the service life of the rotor but also fully disperses and distributes the refining gas delivered from the gas holder to all parts of the aluminum melt. This achieves efficient hydrogen removal while reducing aluminum molten metal splashing, improving degassing efficiency, reducing maintenance frequency, and making it convenient to use. Attached Figure Description
[0013] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a cross-sectional structural diagram of the present invention.
[0014] In the diagram: 1 rotor, 2 impeller, 3 baffle, 4 external thread groove, 5 flange, 6 mounting sleeve, 61 internal thread groove. Detailed Implementation
[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0016] Please see Figure 1-2 This utility model provides a technical solution: a silicon nitride rotor structure based on coordinated control of rotation speed and immersion depth, including a rotor 1. The rotor 1 is made of hollow silicon carbide material with a lifespan of up to 24 months, while the original graphite rotor has a lifespan of 1 month. An impeller 2 is installed at the bottom of the rotor 1. The impeller 2 is a double-layer guide impeller. The impeller 2 is close to the bottom of the degassing box, and a flange 5 is installed at the top of the rotor 1. A baffle 3 is provided on the upper side of the rotor 1 to protect the flange 5. The rotor 1 is made of silicon nitride material and works with the baffle 3 and impeller 2. The baffle 3 can block the splashed aluminum liquid caused by air pressure and shear force on the surface of the aluminum liquid below the baffle 3, preventing the aluminum liquid from splashing between the flange 5 and the external drive motor and causing the rotor 1 to not rotate.
[0017] Furthermore, the upper side of the rotor 1 is provided with an external thread groove 4, the bottom of the flange 5 is provided with a mounting sleeve 6, the inner side of the mounting sleeve 6 is provided with an internal thread groove 61, and the rotor 1 is threadedly connected to the mounting sleeve 6.
[0018] Furthermore, the inner diameter of rotor 1 is 50mm and the outer diameter of rotor 1 is 80mm. The inner and outer diameter dimensions of the rotor are redesigned to reduce costs.
[0019] Furthermore, the baffle 3 has a diameter of 180mm and is made of high-temperature resistant stainless steel, which can shield splashed aluminum liquid. The anti-condensation aluminum design reduces cleaning work and reduces maintenance frequency by 90%.
[0020] Furthermore, the rotor 1 is threadedly connected to the impeller 2, and the impeller 2 has through holes that penetrate its upper and lower surfaces and communicate with the interior of the rotor 1, so that gas can be discharged from different positions.
[0021] Furthermore, the impeller 2 includes an upper disk and a lower disk, and guide plates are evenly arranged between the upper disk and the lower disk. The upper disk is installed at the bottom of the rotor 1. The double-layer guide impeller structure can make the bubbles finer, reaching 1-3mm, with more complete bubble distribution, and the degassing efficiency can reach 60%-70%, with a stable hydrogen content of ≤0.12ml / 100gAl.
[0022] This invention features a baffle plate 3 and a double-layer guide impeller sequentially mounted on a silicon nitride rotor 1. This not only improves the service life of the rotor 1 but also effectively disperses and distributes the refining gas from the gas holder to all parts of the molten aluminum. This achieves efficient hydrogen removal while reducing aluminum molten aluminum splashing, improving degassing efficiency, and lowering maintenance frequency, making it convenient to use.
[0023] The parts not disclosed in this utility model are all prior art, and their specific structures, materials, and working principles will not be described in detail. Although embodiments of this utility model have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of this utility model, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A silicon nitride rotor structure based on coordinated control of rotational speed and immersion depth, comprising a rotor (1), characterized in that: The rotor (1) is made of hollow silicon carbide material. An impeller (2) is installed at the bottom of the rotor (1). The impeller (2) is a double-layer guide impeller. A flange (5) is installed at the top of the rotor (1). A baffle (3) is provided on the upper side of the rotor (1) to protect the flange (5).
2. The silicon nitride rotor structure based on coordinated control of rotational speed and immersion depth according to claim 1, characterized in that: The upper side of the rotor (1) is provided with an external thread groove (4), the bottom of the flange (5) is provided with an installation sleeve (6), the inner side of the installation sleeve (6) is provided with an internal thread groove (61), and the rotor (1) is threadedly connected to the installation sleeve (6).
3. The silicon nitride rotor structure based on coordinated control of rotational speed and immersion depth according to claim 1, characterized in that: The rotor (1) has an inner diameter of 50 mm and an outer diameter of 80 mm.
4. The silicon nitride rotor structure based on coordinated control of rotational speed and immersion depth according to claim 1, characterized in that: The diameter of the baffle (3) is 180mm.
5. The silicon nitride rotor structure based on coordinated control of rotational speed and immersion depth according to claim 1, characterized in that: The rotor (1) is threadedly connected to the impeller (2), and the impeller (2) has a through hole that penetrates its upper and lower surfaces and communicates with the inside of the rotor (1).
6. The silicon nitride rotor structure based on coordinated control of rotational speed and immersion depth according to claim 5, characterized in that: The impeller (2) includes an upper disk and a lower disk, and guide plates are evenly arranged between the upper disk and the lower disk, and the upper disk is installed at the bottom of the rotor (1).