Graphite degassing rotor

Abstract

The utility model belongs to the technical field of aluminum and aluminum alloy melt casting degassing, and aims to provide a graphite degassing rotor which comprises a rotating rod and an impeller, the rotating rod is of a long cylindrical structure, an external connecting thread is arranged at the bottom of the rotating rod, and an internal connecting thread is arranged at the top of the rotating rod; the outer connecting thread is connected with the impeller, and a round hole step is arranged at the upper end of the inner connecting thread; a protective sleeve is arranged outside the rotating rod, the protective sleeve is fixed to the rotating rod through threads, and a through ventilation round hole is formed in the rotating rod; internal threads are arranged in the impeller, a plurality of blades are arranged at the bottom of the impeller, and air outlet channels are formed among the blades; an inclined face is arranged at the top of the impeller and connected with the arc chamfer. The aluminum and aluminum alloy melt casting degassing device has the characteristics of compact structure, good degassing effect, low production cost, long service life and the like, and can be widely applied to the technical field of aluminum and aluminum alloy melt casting degassing.

Description

Technical Field

[0001] The utility model relates to the technical field of degassing in aluminum and aluminum alloy melt casting, in particular to a graphite degassing rotor. Background Art

[0002] In the process of aluminum melt casting, the high-temperature aluminum liquid needs to be degassed to ensure the purity of the aluminum liquid. Graphite rotors are the main products widely used in aluminum liquid purification due to their good non-stick aluminum and processing properties. Most graphite rotors are composed of a rotor and an impeller. There are vents inside the rotor. High-purity inert gas enters the aluminum liquid through the vents and disperses the gas through the rotating impeller to remove hydrogen and oxidized inclusions in the aluminum liquid, thereby purifying the aluminum liquid. However, graphite oxidizes in air above 600°C, and the oxidation results in the rotor shaft becoming gradually thinner until it breaks and becomes scrapped.

[0003] At present, anti-oxidation treatment is widely used to increase the service life of the rotor. For example, patent application number "201020600241.7" introduces a graphite rotor used in aluminum liquid degassing machine, which forms a dihydrogen aluminum phosphate penetration layer on the surface through vacuum impregnation to achieve the purpose of anti-oxidation. However, since graphite itself is relatively dense, the penetration often only stays on the surface of the rotor or 0.2~1.0cm below the surface. Once the thin surface anti-oxidation layer is worn, the failure of the rotor is immediately aggravated, and the service life cannot reach the expected effect; in addition, since anti-oxidation requires vacuum and pressurization, the equipment cost is high, and the impregnation liquid also needs high temperature curing, resulting in its high production cost. Therefore, how to further improve the oxidation resistance of graphite degassing rotors and extend the service life of graphite rotors at low cost has become an important issue in this industry. Summary of the invention

[0004] The utility model aims to provide a graphite degassing rotor, which has the characteristics of compact structure, good degassing effect, low production cost and long service life, and can be widely used in the field of aluminum and aluminum alloy melt casting degassing technology.

[0005] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme to implement it: a graphite degassing rotor, including a rotating rod and an impeller, the rotating rod is a long cylindrical structure, with an external connecting thread at the bottom and an internal connecting thread at the top; the external connecting thread is connected to the impeller, and the upper end of the internal connecting thread is provided with a circular hole step; a sleeve is provided on the outside of the rotating rod, and the sleeve is fixed to the rotating rod by threads, and a through ventilation hole is provided inside the rotating rod; the impeller is provided with an internal thread inside, a plurality of blades are provided at the bottom, and an air outlet channel is provided between the blades; the top of the impeller is provided with an inclined surface, and the inclined surface is connected to the circular arc chamfer.

[0006] As a further improvement of the present invention, the external connection thread is a common M-type thread, and the thread size is smaller than the diameter of the rotating rod.

[0007] As a further improvement of the present invention, the diameter of the external connection thread is 75% to 85% of the diameter of the rotating rod.

[0008] As a further improvement of the present invention, the diameter of the circular hole step is larger than the diameter of the internal connection thread.

[0009] As a further improvement of the present invention, the internal connecting thread is a T-type thread, which is connected to the iron connecting rod of the degasser through the T-type thread to achieve high-speed rotation degassing of the rotating rod.

[0010] As a further improvement of the utility model, the sheath is a hollow cylindrical structure with a long internal thread inside, and the length of the sheath is 200~500mm and the thickness is 15~35mm.

[0011] As a further improvement of the present invention, the sheath material is one of graphite, aluminum silicate, and calcium silicate, and is provided with a silicon carbide coating on the surface, the thickness of the silicon carbide coating is 0.5~1.0mm, and the sheath is always located at the contact surface with the uppermost layer of the aluminum liquid.

[0012] As a further improvement of the present invention, the circular ventilation hole is located at the center of the rotating rod and has a diameter of φ10~φ16mm.

[0013] As a further improvement of the utility model, a U-shaped groove structure is provided inside the blade.

[0014] As a further improvement of the present invention, the number of the blades is 6 to 12, and they are evenly distributed on the outer diameter of the impeller along the circumference.

[0015] The beneficial effects of the utility model include: a graphite degassing rotor with the characteristics of compact structure, good degassing effect, low production cost and long service life. A sheath is set at the place where the aluminum liquid is in contact, so as to focus on protecting the parts of the rotating rod that are prone to wear. Since the thickness of the sheath is relatively thick and the surface is provided with a silicon carbide coating, the service life of the rotating rod is effectively extended. A round hole step is set at the top of the graphite rotating rod, and a gasket is used behind the iron connecting rod to further play a sealing role, so as to prevent the inert gas introduced from leaking from the top and affecting the degassing efficiency. In addition, the impeller adopts a multi-blade and ventilation channel structure, so as to have a better dispersion effect on the inert gas entering the aluminum liquid, ensure that the gas is finer and more uniform, and has a better adsorption and removal effect on hydrogen and oxidized inclusions mixed in the aluminum liquid, thereby effectively improving the degassing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1This is a schematic diagram of the structure of the graphite degassing rotor rod of the utility model;

[0017] Figure 2 This is a schematic diagram of the structure of the graphite degassing rotor impeller of the utility model;

[0018] Figure 3 This is the AA cross-sectional view of the graphite degassing rotor impeller of the utility model;

[0019] Figure 4 This is a schematic diagram of the structure of the graphite degassing rotor sleeve of the utility model.

[0020] In the figure: 1. rotating rod; 2. impeller; 3. external connecting thread; 4. internal connecting thread; 5. circular hole step; 6. vent hole; 7. internal thread; 8. blade; 9. air outlet channel; 10. inclined surface; 11. arc chamfer; 12. long internal thread; 13. silicon carbide coating; 14. U-shaped groove structure; 15. sheath. DETAILED DESCRIPTION

[0021] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments: Figures 1 to 4 As shown, a graphite degassing rotor of the utility model comprises a rotating rod 1 and an impeller 2, wherein the rotating rod 1 is a long cylindrical structure, with an external connecting thread 3 at the bottom and an internal connecting thread 4 at the top; the external connecting thread 3 is connected to the impeller 2, and a circular hole step 5 is provided at the upper end of the internal connecting thread 4; a sleeve 15 is provided on the outside of the rotating rod 1, and the sleeve 15 is fixed on the rotating rod 1 by threads, and a through ventilation circular hole 6 is provided inside the rotating rod 1; the impeller 2 is provided with an internal thread 7 inside, and a plurality of blades 8 are provided at the bottom, and an air outlet channel 9 is provided between the blades 8; a bevel 10 is provided on the top of the impeller 2, and the bevel 10 is connected to the circular arc chamfer 11. Specifically, the bevel 10 and the circular arc chamfer 11 can reduce the rotational shear force of the impeller 2 in the high-temperature aluminum liquid, so that the rotation of the rotating rod 1 is more stable and labor-saving.

[0022] Furthermore, the external connecting thread 3 is a common M-type thread, and the thread size is smaller than the diameter of the rotating rod 1; specifically, the diameter of the external connecting thread 3 is 75%~85% of the diameter of the rotating rod 1, preferably 80%. For example, if the diameter of the rotating rod 1 is 80mm, the size of the external connecting thread 3 is M64mm, because if the external connecting thread 3 is too large, the impeller 2 connected thereto will slide upward to the rotating rod 1 shortly after use, and if the external connecting thread 3 is too small, it will affect the connection strength and stability, and there is a risk of falling off or breaking.

[0023] Furthermore, the diameter of the circular hole step 5 is larger than the diameter of the internal connecting thread 3; specifically, a graphite sealing gasket is provided on the circular hole step 5. When the iron connecting rod of the degasser is connected to the internal connecting thread 3, the iron connecting rod has a protruding structure with a diameter slightly smaller than the circular hole step. After entering the circular hole step 5, the graphite sealing gasket is pressed to prevent inert gas from leaking from the threaded connection and affecting the degassing efficiency; further, the internal connecting thread 3 is a T-type thread, which is connected to the iron connecting rod of the degasser through the T-type thread, ensuring a more stable connection and a larger output torque, thereby realizing high-speed rotation degassing of the rotating rod.

[0024] Furthermore, the sheath 15 is a hollow cylindrical structure with a long internal thread 12 inside, and the length of the sheath is 200~500mm, preferably 300~400mm, and the thickness is 15~35mm, preferably 20~25mm; specifically, the sheath 15 is made of one of graphite, aluminum silicate, and calcium silicate, preferably graphite, and a silicon carbide coating 13 is provided on the surface, the thickness of the silicon carbide coating 13 is 0.5~1.0mm, and the sheath 15 is always located at the contact surface with the uppermost layer of the aluminum liquid, thereby protecting the rotating rod, effectively solving the problem that the rotating rod is easily carbonized and worn on the contact surface with the aluminum liquid, and greatly extending the service life of the graphite rotating rod.

[0025] Furthermore, the circular ventilation hole 6 is located at the center of the rotating rod 1 and has a diameter of φ10-φ16 mm, preferably φ12-φ14 mm, and inert gas is introduced into the high-temperature aluminum liquid through the circular ventilation hole 6 .

[0026] Furthermore, a U-shaped groove structure 14 is provided inside the blade 8; specifically, the number of the blades 8 is 6 to 12, preferably 6 to 8, and is evenly distributed on the outer diameter of the impeller 2 according to the circumference. The impeller adopts a multi-blade and ventilation channel structure, which has a better dispersion effect on the inert gas entering the aluminum liquid, ensuring that the gas is finer and more uniform, and has a better adsorption and removal effect on hydrogen and oxidized inclusions in the aluminum liquid, thereby effectively improving the degassing efficiency.

[0027] The graphite degassing rotor of the utility model has the characteristics of compact structure, good degassing effect, low production cost and long service life. By arranging an additional sheath on the contact surface of the aluminum liquid, the sheath has a thick thickness, and has a longer service life than the surface anti-oxidation layer of the graphite rotating rod. At the same time, the production is simple and the equipment investment is small. The rotating rod 1 and the impeller 2 are connected by the external connecting thread 3, and the rotating rod 1 is connected and fixed to the degasser by the internal connecting thread 3. The inert gas enters the high-temperature aluminum liquid through the penetrating ventilation circular hole 6, and is broken into dispersed small bubbles by the high-speed rotating impeller 2. The small bubbles adsorb the hydrogen and oxidized inclusions contained in the aluminum liquid and bring them out to the surface of the aluminum liquid, so as to achieve the degassing and purification effect.

[0028] The utility model can be summarized in other specific forms that do not violate the spirit and main features of the utility model. Therefore, no matter from which point of view, the above-mentioned embodiments of the utility model can only be regarded as an illustration of the utility model but not as a limitation of the utility model. Therefore, any changes within the meaning and scope equivalent to the claims of the utility model should be considered to be included in the scope of the claims.

Claims

1. A graphite degassing rotor, comprising a rotating rod (1) and an impeller (2), wherein the rotating rod (1) is a long cylindrical structure, with an external connecting thread (3) at the bottom and an internal connecting thread (4) at the top; characterized in that: The external connection thread (3) is connected to the impeller (2), and a circular hole step (5) is provided at the upper end of the internal connection thread (4); a sleeve (15) is provided on the outside of the rotating rod (1), and the sleeve (15) is fixed to the rotating rod (1) by means of threads, and a through-going vent hole (6) is provided inside the rotating rod (1); the impeller (2) is provided with an internal thread (7), and a plurality of blades (8) are provided at the bottom, and air outlet channels (9) are provided between the blades (8); a slope (10) is provided on the top of the impeller (2), and the slope (10) is connected to a circular arc chamfer (11).

2. The graphite degassing rotor according to claim 1, characterized in that: The external connection thread (3) is a common M-type thread, and the thread size is smaller than the diameter of the rotating rod (1).

3. The graphite degassing rotor according to claim 2, characterized in that: The diameter of the external connection thread (3) is 75% to 85% of the diameter of the rotating rod (1).

4. The graphite degassing rotor according to claim 1, characterized in that: The diameter of the circular hole step (5) is greater than the diameter of the internal connection thread (4).

5. The graphite degassing rotor according to claim 4, characterized in that: The internal connection thread (4) is a T-type thread, and is connected to the iron connection rod of the degasser via the T-type thread.

6. The graphite degassing rotor according to claim 1, characterized in that: The sheath (15) is a hollow cylindrical structure, and a long internal thread (12) is provided inside.

7. The graphite degassing rotor according to claim 6, characterized in that: The sheath (15) is made of one of graphite, aluminum silicate and calcium silicate, and is provided with a silicon carbide coating (13) on its surface. The thickness of the silicon carbide coating (13) is 0.5-1.0 mm, and the sheath (15) is always located at the contact surface with the uppermost layer of the aluminum liquid.

8. The graphite degassing rotor according to claim 1, characterized in that: The circular ventilation hole (6) is located at the center of the rotating rod (1) and has a diameter of φ10-φ16 mm.

9. The graphite degassing rotor according to claim 1, characterized in that: A U-shaped groove structure (14) is provided inside the blade (8).

10. The graphite degassing rotor according to claim 9, characterized in that: The number of the blades (8) is 6 to 12, and they are evenly distributed on the outer diameter of the impeller (2) along the circumference.

Images