JP4749567B2 - Molten filtration tank - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure of a filtration tank for filtering molten metal such as molten aluminum or molten aluminum alloy.
[0002]
[Prior art and problems to be solved by the invention]
Conventionally, inclusions such as non-metallic inclusions are often mixed in molten metal such as molten aluminum and molten aluminum alloy used for casting due to various origins during the melting process. Therefore, in order to produce a good metal casting, it is necessary to remove inclusions in the molten metal prior to casting.
[0003]
For this purpose, it is generally performed to remove inclusions by temporarily storing the molten metal in a filtration tank and passing the filter through a filter disposed in the filtration tank. As the filter, a cartridge (filter cartridge) is used in which a plurality of filters made of a cylindrical ceramic porous body are arranged and fixedly held.
[0004]
In FIG. 6, the schematic sectional drawing of the conventional filtration tank is shown. In FIG. 6, the filtration tank has a main body portion 2 and a lid portion 4 adapted to be detachable so as to close the upper opening of the main body portion 2. The main body 2 is provided with a hot water inlet 12 and a hot water outlet 14. A communication opening 16 that communicates with the hot water outlet 14 is formed in the main body 2, and a filter cartridge 18 is fitted in the communication opening. The filter cartridge 18 includes a plurality of cylindrical filters 18a, a front plate 18b attached to one end of each of the plurality of filters 18a, and the other end of the plurality of filters 18a. And a rear side plate 18c attached to the rear side plate 18c. A wedge 19 for holding the filter cartridge 18 is inserted between the rear plate 18 c and the inner wall of the main body 2. The end of the filter 18a joined to the front plate 18b is opened, and the end joined to the rear plate 18c is closed. Openings 18b1 are formed in the front side plate 18b at positions corresponding to the respective filters 18a, whereby the open ends of the respective filters 18a and the hot water outlet 14 are communicated with each other through the communication openings 16.
[0005]
The molten metal to be filtered enters the filtration tank from the inlet 12 and permeates from the outside to the inside of the filter 18a, and the inclusions are excluded. The filtered molten metal exits the filtration tank from the hot water outlet 14 through the communication opening 16 from the open end of each filter 18a.
[0006]
In order to prevent the molten metal in the filtration tank from leaking to the communication opening 16 without passing through the filter 18a, a ceramic fiber gasket 28 is interposed between the front plate 18b and the inner wall where the communication opening 16 is formed. It is done. By the way, in order to continue the molten metal leakage prevention from this part over a long period of time, it is important to keep the distance between the inner wall of this part and the front side plate 18b uniform and constant over the entire circumference. For this reason, the square-shaped portion in which the communication opening 16 is formed is formed by a heat-resistant annular member called a frame brick, and the surface facing the front side plate 18b of the annular member is made sufficiently smooth and in the vertical direction. To be along. Conventionally, in order to achieve the above-described purpose, the annular member has been integrated with the inner wall of the filtration tank (that is, fixed by a bonding material) in order to maintain the posture of the annular member constant.
[0007]
However, in such a conventional filtration tank, the melt is gradually accumulated due to the thermal expansion and contraction generated in the annular member and the surrounding heat-resistant member by repeatedly performing molten metal filtration. Or a position shift occurs in the annular member, and the posture changes so that the distance between the surface facing the front side plate 18b and the front side plate 18b cannot be maintained uniformly and constant, and the molten metal leakage prevention by the gasket 28 cannot be prevented. Sometimes.
[0008]
Once the molten metal leakage prevention function is impaired, it is necessary to replace the annular member with a new one. However, in the conventional filtration tank structure, the annular member is integrated with the filtration tank main body 2. In addition, it is necessary to perform an exchanging operation for simultaneously removing an annular member and a corresponding heat-resistant member around the annular member and fixing a new one. This replacement work is extremely troublesome and time-consuming, and the productivity is significantly reduced due to the interruption of the filtration work during that time.
[0009]
Accordingly, an object of the present invention is to provide a molten metal filtration tank that can reduce the frequency of breakage and posture change of an annular member that forms a communication opening with a hot water outlet and can be easily replaced. To do.
[0010]
[Means for Solving the Problems]
According to the present invention, the object as described above is achieved.
In the molten metal filtration tank for filtering the melt to be filtered introduced from the hot water inlet through a filter member attached to the communication opening that communicates with the hot water outlet and discharging it from the hot water outlet as a filtered molten metal,
The molten metal filtration tank, wherein the filter member is abutted against an annular member forming the communication opening, and the annular member is adapted to the tank wall via a cushion member,
Is provided.
[0011]
In one aspect of the present invention, the cushion member comprises a ceramic fiber.
[0012]
In one aspect of the present invention, a ceramic fiber mortar is filled between the annular member and the tank wall so as to prevent the cushion member from being exposed to the molten metal to be filtered.
[0013]
In one aspect of the present invention, the annular member is adapted to the tank wall from the side on which the filter member abuts, and the outer peripheral surface of the annular member gradually increases from the side on which the filter member abuts to the opposite side. The tapered surface reduces the outer diameter. In one aspect of the present invention, the taper angle of the tapered surface is 2 ° to 20 °. In one aspect of the present invention, the thickness of the cushion member interposed between the tapered surface and the surface of the tank wall corresponding to the tapered surface is 5 mm to 20 mm.
[0014]
In one aspect of the present invention, a first convex portion or a first concave portion is formed in an annular shape on the end surface of the annular member opposite to the side on which the filter member abuts, and the first convex portion Or the 2nd recessed part or 2nd convex part is formed in the surface of the said tank wall corresponding to a 1st recessed part cyclically | annularly.
[0015]
In one aspect of the present invention, a ceramic fiber sheet is interposed between the end surface of the annular member opposite to the side on which the filter member abuts and the surface of the tank wall corresponding to the end surface.
[0016]
In one aspect of the present invention, the end surface of the annular member on the side where the filter member abuts protrudes from the surface of the tank wall by 1 mm to 5 mm.
[0017]
In one aspect of the present invention, the filter member includes a filter made of a cylindrical ceramic porous body and a side plate attached to one end that can be opened, and the side plate includes one end of the filter. An opening is formed corresponding to the opening, the opening communicates with the communication opening, and the side plate is in contact with the annular member. In one aspect of the present invention, a ceramic fiber gasket is interposed between the annular member and the side plate.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0019]
FIG. 1 is a schematic exploded sectional view showing a configuration of an embodiment of a molten metal filtration tank according to the present invention, FIG. 2 is a partially enlarged sectional view thereof, and FIG. 3 is a front view of an annular member.
[0020]
The filtration tank has a main body portion 2 and a lid portion 4 adapted to be detachable so as to close the upper opening of the main body portion 2. The main body 2 is provided with a hot water inlet 12 and a hot water outlet 14. The main body 2 is formed with a communication opening 16 that communicates with the hot water outlet 14, and a filter cartridge 18 as a filter member is fitted into the communication opening.
[0021]
The filter cartridge 18 includes a plurality of cylindrical filters 18a made of a ceramic porous body such as an alumina porous body, a front side plate 18b attached to one end of the plurality of filters 18a, and a plurality of filters. And a rear plate 18c attached to the other end of 18a so as to gather them together. A wedge 19 for holding the filter cartridge 18 is inserted between the rear plate 18 c and the inner wall of the main body 2. The front side plate 18b, the rear side plate 18c and the wedge 19 are made of, for example, a silicon carbide refractory. The end of the filter 18a joined to the front plate 18b is opened, and the end joined to the rear plate 18c is closed. Openings 18b1 are formed in the front side plate 18b at positions corresponding to the respective filters 18a, whereby the open ends of the respective filters 18a and the hot water outlet 14 are communicated with each other through the communication openings 16.
[0022]
The molten metal to be filtered (filtered molten metal) enters the filtration tank from the hot water inlet 12 and is filtered when permeating from the outside to the inside of the filter 18a, and inclusions are excluded. The filtered molten metal (filtered molten metal) exits the filtration tank from the outlet 14 through the communication opening 16 from the open end of each filter 18a.
[0023]
In the present embodiment, the front plate 18 b of the filter cartridge 18 is brought into contact with an annular member 20 that forms the communication opening 16, and the annular member 20 is a cushion member 24 against the tank wall 22 of the filtration tank main body 2. Has been adapted through. The annular member 20 is called a frame brick, and is made of, for example, a refractory material of silicon carbide or alumina. The cushion member 24 includes a ceramic fiber. The thickness T1 of the cushion member 24 is, for example, 5 mm to 20 mm. As the cushion member 24, a relatively short-fiber cotton-like ceramic fiber (hard fiber) called a bulk fiber can be used. This is characterized by excellent heat resistance, resistance to rapid heating and quenching, chemical stability, and easy cutting and processing. Bulk fiber should be used with appropriate thickness. Moreover, as the cushion member 24, what is called a fiber blanket (obtained by laminating fibers and needle processing) can also be used. This fiber blanket is particularly characterized by high tensile strength. A fiber blanket having an appropriate thickness is cut into a predetermined region shape and used. Furthermore, as the cushion member 24, what is called a fiber rope (a rope blank formed by covering an elongated fiber blanket with a heat-resistant glass fiber) can be used. The fiber rope is used by laying in parallel so as to cover a predetermined area.
[0024]
As shown in FIG. 2, the annular member 20 is not integrally fixed to the tank wall 22, and the direction of the arrow A in the drawing (that is, the side opposite to the side on which the front plate 18 b abuts). The tank wall 22 is adapted in the direction toward the head. The outer peripheral surface of the annular member 20 is a tapered surface, and the outer diameter dimension gradually decreases in the direction of arrow A in the figure. The taper angle θ of this tapered surface is preferably 2 ° to 20 °. If the taper angle θ is too small, it is difficult to pull out the annular member 20 when it is replaced. If the taper angle θ is too large, the annular member 20 tends to fall off during mounting.
[0025]
An annular convex portion 20 ′ is formed on the end surface of the annular member 20 opposite to the side on which the front plate 18 b abuts. 'Is formed. A ceramic fiber sheet 26 is interposed between the end surface of the annular member 20 where the convex portion 20 ′ is formed and the surface of the tank wall 22 where the concave portion 22 ′ is formed. The ceramic fiber sheet 26 is formed by molding a bulk fiber into a paper shape, is flexible, and has excellent heat resistance and sealing properties. The ceramic fiber sheet 26 is cut into a required shape using scissors or the like. The thickness T2 of the ceramic fiber sheet 26 is, for example, 2 mm to 10 mm. Instead of forming the annular protrusion 20 ′ on the annular member 20, an annular recess may be formed, and instead of forming the annular recess 22 ′ on the tank wall 22, an annular protrusion may be formed. Thus, the annular member 20 and the tank are formed by forming the annular convex part 20 ′ or the annular concave part on the annular member 20 and forming the annular concave part 22 ′ or the annular convex part on the tank wall 22 so as to correspond thereto. In addition to exhibiting the effect of suppressing molten metal leakage between the wall 22 and the wall 22, the effect of preventing the annular member 20 from shifting from a predetermined position can also be exhibited.
[0026]
A space between the annular member 20 and the tank wall 22 is filled with a ceramic fiber mortar 25 having good corrosion resistance against the molten metal so as to prevent the cushion member 24 from being exposed to the molten metal to be filtered. The ceramic fiber mortar 25 is a refractory fiber-based mortar, which has good wear resistance, heat insulation properties, high strength, low shrinkage, and particularly good corrosion resistance against molten metal such as an aluminum alloy, and is dried by a gas burner or the like. The bulk density is, for example, 0.80 to 0.82 g / cm ³ , which results in no penetration in a 72 hour corrosion resistance test on aluminum alloys.
[0027]
The end surface of the annular member 20 on the side where the front plate 18b comes into contact protrudes from the surface of the tank wall 22 by T3, for example, 1 mm to 5 mm. A ceramic fiber gasket 28 for preventing molten metal leakage is interposed between the end face and the front side plate 18b.
[0028]
In the present embodiment, unlike the conventional molten metal filtration tank, the annular member 20 is not fixed to the tank wall 22 but is held with a cushion member 24 interposed therebetween, and the front plate 18b of the filter cartridge 18 is used. The predetermined position is maintained by receiving the pressing force in the direction of arrow A. Thus, since the annular member 20 is loosely attached to the tank wall 22 via the cushion member 24, the stress generated in the filtration tank main body tank wall 22 due to repeated molten metal filtration is transmitted to the annular member 20. Absorption can be reduced by the cushion member 24 without doing so. For this reason, in the conventional molten metal filtration tank, the annular member is easily damaged mainly by the pressure from the outside to the inside in the radial direction. However, in the embodiment of the present invention, such pressure is absorbed by the cushion member 24. Even if the molten metal filtration is repeated, distortion is not easily accumulated in the annular member 20, so that the annular member 20 is less likely to be damaged or changed in posture, and it is possible to extend the life of the annular member 20 and to maintain the molten metal leakage preventing action by the gasket 28 for a long time. It becomes.
[0029]
When the annular member 20 is replaced, after the molten metal in the filtration tank is removed, the drawing tool is first locked in the locking hole 19a formed in the wedge 19 as shown in FIG. And then remove the filter cartridge 18 as shown in FIGS. Next, as shown in FIG. 5, the annular member 20 is pulled out toward the inside of the filtration tank in the direction opposite to the direction of the arrow A. At that time, the cushion member 24 and the ceramic fiber sheet 26 are removed together with the annular member 20, or remain attached to the filtration tank body tank wall 22. This residual fiber can be easily peeled off from the tank wall 22. Thereafter, a new annular member 20 is mounted via a new ceramic fiber sheet 26 and a new cushion member 24, and the filter cartridge 18 is disposed. And the filter cartridge 18 arrange | positioned in this predetermined position is fixed by the intervention of the wedge 19 in a predetermined position. This replacement operation is easy and can be completed in a short time because the annular member 20 is not fixed to the tank wall 22 and the tank wall 22 does not need to be replaced. Therefore, the decrease in productivity due to the interruption of the molten metal filtration operation is small.
[0030]
【The invention's effect】
As described above, according to the present invention, since the annular member is loosely adapted to the filtration tank main body tank wall via the cushion member, the life of the annular member can be prolonged, and the The work for exchanging the annular member with a new one can be performed easily and in a short period of time, and the period for stopping the filtration work for exchanging the annular member can be shortened, which is more productive than conventional filtration tanks. Can be greatly improved.
[Brief description of the drawings]
FIG. 1 is a schematic exploded sectional view showing a configuration of a molten metal filtration tank according to the present invention.
FIG. 2 is a partially enlarged cross-sectional view of FIG.
FIG. 3 is a front view of an annular member.
FIG. 4 is an explanatory diagram of an annular member replacement operation.
FIG. 5 is an explanatory diagram of an annular member replacement operation.
FIG. 6 is a schematic cross-sectional view showing a configuration of a conventional molten metal filtration tank.
[Explanation of symbols]
2 Filtration tank main body part 4 Filtration tank lid part 12 Hot water inlet 14 Hot water outlet 16 Communication opening 18 Filter cartridge 18a Cylindrical filter 18b Front side plate 18c Rear side plate 19 Wedge 19a Locking hole 20 Annular member 20 'Convex part 22 Filtration tank main body part Tank wall 22 'Recess 24 Cushion member 25 Ceramic fiber mortar 26 Ceramic fiber sheet 28 Ceramic fiber gasket

Claims (10)

In the molten metal filtration tank for filtering the melt to be filtered introduced from the hot water inlet through the filter member and discharging it from the hot water outlet as a filtered molten metal,
An annular member is adapted to the tank wall of the molten metal filtration tank, and the annular member forms a communication opening that communicates with the outlet.
A cushion member is interposed between the outer peripheral surface of the annular member and the tank wall ,
The filter member includes a side plate adapted to the annular member and a filter attached to an opening formed in the side plate, and the side plate is attached to the annular member such that the opening communicates with the communication opening. Abut,
A first convex portion or a first concave portion is formed in an annular shape on the end surface of the annular member opposite to the side on which the side plate abuts, and corresponding to the first convex portion or the first concave portion. The molten metal filtration tank, wherein the tank wall is formed with a second concave portion or a second convex portion in an annular shape .   The molten metal filtration tank according to claim 1, wherein the cushion member includes a ceramic fiber.   The ceramic fiber mortar is filled between the annular member and the tank wall so as to prevent the cushion member from being exposed to the molten metal to be filtered. The molten metal filtration tank of crab.   The annular member is adapted to the tank wall from the side on which the filter member abuts, and the outer peripheral surface of the annular member gradually decreases in outer diameter from the side on which the filter member abuts to the opposite side. It is set as the taper surface, The molten metal filtration tank in any one of Claims 1-3 characterized by the above-mentioned.   The molten metal filtration tank according to claim 4, wherein a taper angle of the tapered surface is 2 ° to 20 °.   The thickness of the said cushion member interposed between the said taper surface and the surface of the said tank wall corresponding to this taper surface is 5 mm-20 mm, It is characterized by the above-mentioned. Melt filtration tank. Wherein the ceramic fiber sheet is interposed between the surface of the tank wall, wherein the filter member of the annular member corresponding to the end face and the end face opposite to the side contacting, claims 1-6 A molten metal filtration tank according to any one of the above. The molten metal filtration tank according to any one of claims 1 to 7 , wherein an end surface of the annular member on a side where the filter member abuts protrudes from a surface of the tank wall by 1 mm to 5 mm. The molten metal filtration tank according to any one of claims 1 to 8 , wherein the filter is made of a cylindrical ceramic porous body, and the side plate is attached to one end of the filter that can be opened. The molten metal filtration tank according to claim 1 , wherein a ceramic fiber gasket is interposed between the annular member and the side plate.

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