JPH0241159Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a molten metal filtration device for removing non-metallic inclusions contained in molten metal such as molten aluminum.

(Prior Art) As shown in FIG. 2, this type of molten metal filtration device is assembled by fixing both ends of a plurality of hard ceramic tubes 20 between tube attachment recesses 22 of an end plate 21 facing each other. It is common to have a three-dimensional structure, and such an assembly is fixed within the tank body 23 using a wedge plate 24 or the like. However, the mirror plate 21
is made of a silicate-bonded silicon carbide refractory, while the hard ceramic tube 20 is usually made of molten alumina aggregate bonded with a special binder, and each part has different thermal expansion. Thermal distortion occurred when the temperature was raised, causing problems such as damage to the hard ceramic tube 20 and end plate 21, and cracks.

Therefore, as shown in Japanese Utility Model Application Publication No. 59-68663, a structure is proposed in which the open end of the tube is fixed to the end plate with mortar and ring-shaped packing, and the closed end of the tube is fixed to the end plate with mortar. As shown in Japanese Patent No. 69959, a structure has been proposed in which one end of the tube is attached to the end plate through a gasket, and the other end is completely fixed to the end plate with mortar. However, in both cases, both ends of the tube are installed in the tube mounting recesses of the end plate, and the gasket also shrinks and deforms when the assembly is firmly fixed in the tank by the wedge plate, which reduces thermal expansion. It was not sufficiently effective, and it was not possible to completely prevent cracking due to thermal stress during temperature rise. In addition, the latter is easy to damage because the parts that are not fixed by mortar come off when transporting the assembly or lifting the assembly with a crane or the like and setting it in the tank, and when a gasket is attached to the open end of the tube. However, there were problems such as the tendency for molten metal to leak.

(Problems to be solved by the invention) The present invention solves the above-mentioned conventional problems and can sufficiently absorb thermal strain during temperature rise.
It was also completed with the aim of creating a molten metal filtration device that would not cause problems such as damage to the assembly or leakage of molten metal during transportation.

(Means for Solving the Problems) The present invention is a molten metal filtration device in which an assembly formed by fixing a plurality of bottomed hard ceramic tubes between opposing end plates is installed in a tank. A through hole slightly larger than the outer diameter of the hard ceramic tube is formed in the end plate on the closed end side of the hard ceramic tube, and the open end of the hard ceramic tube is inserted and fixed into the tube mounting recess of the end plate on the open end side. , the closed end is loosely fixed to the inner circumferential surface of the through hole such that the outer end surface thereof is flush with or slightly inside the outer surface of the end plate.

(Example) Next, the present invention will be described in detail with reference to the illustrated embodiment. 1 is a tank body, and 2 is a partition wall that divides the inside of the tank body 1 into a filtration tank 3 and a cleaning tank 4. Also 5
is an assembly installed in a tank, and this assembly 5 consists of a plurality of bottomed cylindrical hard ceramic tubes 6, 6 fixed between opposing end plates 7, 7. Hard ceramic tube 6
A communication hole 8 is formed in one end plate 7 and the partition wall 2 corresponding to the open end of the cleaning tank 4 to allow the filtered molten metal to pass through the cleaning tank 4.
It is now possible to lead to

In this invention, each hard ceramic tube 6
As shown in the figure, a through hole 9 slightly larger than the outer diameter of the hard ceramic tube 6 is formed in the end plate 7 on the closed end side, and a tube mounting recess 10 is formed in the end plate 7 on the open end side as in the conventional case. has been done. The closed end of the hard ceramic tube 6 is fixed to the inner circumferential surface of the through hole 9 with mortar, ceramic fiber, etc. At this time, the outer end surface 11 of the hard ceramic tube 6 is fixed to the outer surface of the end plate 7 12, or slightly inward of this outer surface 12 by several millimeters. Furthermore, the open end of the hard ceramic tube 6 is securely fixed to the end plate 7 by mortar, but the closed end side is fixed to the end plate 7 more gently than the open end by mortar or ceramic fibers having a cushioning property. shall be fixed at

Note that 13 is a wedge plate for firmly fixing such an assembly 5 between the side wall of the tank body 1 and the partition wall 2, 14 is an inlet for molten metal, and 15 is an outlet for filtered molten metal. .

(Function) A device configured in this way can, for example,
After heating the entire tank to about 800°C at a heating rate of Hr, molten metal such as aluminum is injected into the filtration tank 3 from the injection port 14, and non-metallic inclusions contained in the molten metal are removed. It is a conventional method to filter the molten metal through the outer surfaces of a plurality of hard ceramic tubes 6, to flow only the purified molten metal from the inside of the hard ceramic tubes 6 into the cleaning tank 4 through the communication hole 8, and to take it out from the outlet 15. It is similar to this type of device. However, in this invention, the hard ceramic tube 6
A through hole 9 slightly larger than the outside diameter of the tube is formed in the head plate 7 on the closed end side of the hard ceramic tube 6. Since it is loosely fixed, even if the hard ceramic tube 6 thermally expands due to temperature rise, the closed end of the hard ceramic tube 6 will freely extend inside the through hole 9 of the end plate 7 and will not exert thermal stress on the end plate 7. . Therefore, in the device of the present invention, the hard ceramic tube 6 and end plate 7 do not break due to thermal expansion unlike in the conventional case. In addition, the hard ceramic tube 6 is fixed to the inner circumferential surface of the through hole 9 so that the outer end surface 11 of the closed end thereof is flush with the outer surface 12 of the end plate 7, or is slightly inside thereof. 5 in the tank body 1 with the wedge plate 13. Especially when a gap of several mm is formed between the outer end surface 11 and the outer surface 12 as shown in the figure, this gap is made of hard ceramic. Since the tube 6 serves as an expansion allowance when thermally expanded, the hard ceramic tube 6 can be prevented from hitting the wedge plate 13, and cracking of the hard ceramic tube 6 can be more reliably prevented.

Moreover, in the manufacturing process of the end plate 7, the one with through holes 9 is easier to manufacture than the conventional one with a concave part for attaching the tube, and has the advantage of improving the yield. Since the closed end of the hard ceramic tube 6 is loosely fixed to the end plate 7, the hard ceramic tube 6 will not come off from the end plate 7 even during transportation or assembly of the assembly. Furthermore, in the present invention, since the open end of the hard ceramic tube 6 can be firmly fixed to the end plate 7 with mortar, molten metal will not leak from this part unlike in the case where a conventional gasket is attached.

(Effects of the invention) As is clear from the above explanation, the present invention prevents cracks from occurring in the hard ceramic tube or head plate due to thermal stress during heating or filtration of molten metal, and also prevents cracking during transportation. Not only can troubles such as damage and molten metal leaks during assembly be prevented, but the end plate is also easy to manufacture, which has the advantage of reducing manufacturing costs.
Furthermore, in the present invention, the closed end of the hard ceramic tube exposed in the through hole of the end plate also contributes to filtration, so there is an advantage that the filtration area can be expanded. Therefore, the present invention has extremely great practical value as a molten metal filtration device that solves the problems of the conventional method.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view showing an embodiment of the present invention, and FIG. 2 is a partially cutaway front view showing main parts of a conventional example. 5: Assembly, 6: Hard ceramic tube,
7: end plate, 9: through hole, 11: outer end surface, 12: outer surface.

Claims (1)

[Scope of utility model registration request] Multiple bottomed hard ceramic tubes 6,6
A molten metal filtration device in which an assembly 5 formed by fixing a molten metal between end plates 7 and 7 facing each other is installed in a tank,
End plate 7 on the closed end side of the hard ceramic tube 6
A through hole 9 slightly larger than the outer diameter of the hard ceramic tube 6 is formed in the hole 9, and the open end of the hard ceramic tube 6 is inserted and fixed into the tube mounting recess 10 of the end plate 7 on the open end side, and the closed end is inserted into the tube mounting recess 10 of the head plate 7 on the open end side. A molten metal filtration device characterized in that the outer end surface 11 is loosely fixed to the inner circumferential surface of the through hole 9 so that the outer end surface 11 is on the same plane as the outer surface 12 of the mirror plate 7 or slightly inside thereof.