WO2007072898A1

WO2007072898A1 - Metal filtration equipment and filter cassette

Info

Publication number: WO2007072898A1
Application number: PCT/JP2006/325471
Authority: WO
Inventors: Tatsumi Tsuyama; Yukihisa Shiraishi; Kazuhiko Kawaguchi; Minoru Kubota
Original assignee: Mitsui Mining & Smelting Co., Ltd.
Priority date: 2005-12-21
Filing date: 2006-12-21
Publication date: 2007-06-28
Also published as: JP4046345B2; JP2007169709A

Abstract

A pair of refractory plates (11,12) are disposed within a unit container. Multiple lengthy ceramic tubes (14) are fitted between the pair of refractory plates (11,12). One end (14a), on the side of melt outlet aperture (9), of each of the ceramic tubes (14) is fixed to the refractory plate (12) by means of refractory cement (22), and the other end (14b) of each of the ceramic tubes (14) is fixed to the refractory plate (11) by means of fiber mortar (21). Thus, retention of the thermal shock resistance and enhancement of the fixing strength of the ceramic tubes (14) are simultaneously attained.

Description

Specification

Metal filtration device and filter cassette

Technical field

[0001] The present invention relates to a metal filtering device and a filter cassette for filtering molten metal, and intends to achieve both improvement in the fixing strength of the ceramic tube and maintenance of thermal shock resistance.

Background art

[0002] Metals, for example, aluminum or aluminum alloy melts are poured into molds to produce desired products. Prior to pouring the molten metal into the bowl during fabrication, the molten metal is filtered with a metal filter to remove inclusions (harmful or unnecessary foreign matter) contained in the molten metal. In the metal filtration device, the molten metal is circulated through a filter cassette having a plurality of ceramic tubes between a pair of side plates, and the inclusions are removed by passing the molten metal through the ceramic tubes to obtain a clean molten metal. (For example, see Patent Document 1 below).

In such a metal filtering device, it is conceivable to attach a ceramic tube to a pair of side plates via a flexible fiber mortar. In such a metal filtration device in which a ceramic tube is attached with a fiber mortar, the flaws caused by expansion of the ceramic tube are reduced, but there is a possibility that the fiber mortar is destroyed by vibration. If the fiber-type mortar on the tapping side is destroyed, the molten metal will not be filtered, which will have a significant effect on the quality of the molten metal.

[0004] Further, in the conventional metal filtration device, inclusions accumulate near the surface layer of the ceramic tube and become clogged due to long-term use. For this reason, there is a case where cleaning gas such as inert gas is intermittently blown from the lower part of the container to prevent clogging of the ceramic tube. When the cleaning gas is blown, the temperature of the molten metal decreases, and when the cleaning gas is stopped, the temperature of the molten metal increases. For this reason, there is a possibility that the ceramic tube expands and contracts due to a temperature change and a gap is formed between the ceramic tube and the side plate. Although it is possible to suppress the generation of a gap between the side plate and the ceramic tube by improving the bonding strength between the ceramic tube and the side plate, there is a risk of cracking in the ceramic tube at the fixed portion. [0005] Patent Document 1: Japanese Patent No. 3317507

Disclosure of the invention

Problems to be solved by the invention

[0006] The present invention has been made in view of the above situation, and a metal filtering device capable of achieving both improvement in the fixing strength of a ceramic tube and maintenance of thermal shock resistance even when it is repeatedly subjected to vibration and sudden temperature changes. And providing a filter cassette.

Means for solving the problem

[0007] To achieve the above object, the metal filtration device of the present invention according to claim 1 of the present invention is a metal filtration device having a hot water inlet and a hot water outlet, and includes a hot water side plate and hot water provided therein. A side plate and a ceramic tube with one end open and a bottomed bottom, a tube attached at one end to the hot water side plate and the other end attached to the hot water side plate. The end of the side is attached to the tapping side plate with the tapping side refractory material, and the bottomed side end of the ceramic tube is attached to the tapping side plate with the tapping side refractory material, and the fixing strength of the tapping side refractory material is ceramic. It is characterized by a higher tensile strength than the tube and a lower bond strength of the refractory material on the hot water side than the tensile strength of the ceramic tube.

[0008] For this reason, the open end of the ceramic tube is attached to the outlet side plate on the outlet side with a refractory material having a fixing strength higher than the tensile strength of the ceramic tube, so that the adhesion strength is maintained and the temperature is maintained. There is no gap even if expansion and contraction due to change occur, and inclusions are suppressed, and expansion and contraction due to vibration and temperature change is a refractory material on the hot water side that has a lower bond strength than the tensile strength of the ceramic tube. Is absorbed at the end of the bottomed side of the ceramic tube attached to the hot water side plate. For this reason, it is possible to achieve both improvement of the fixing strength of the ceramic tube and maintenance of the thermal shock resistance even if it is repeatedly subjected to vibration and sudden temperature changes.

[0009] The metal filtering device of the present invention according to claim 2 of the present invention is the metal filtering device according to claim 1, wherein the tapping side refractory material is a refractory cement, and the tapping side refractory material is a fiber reinforced material. It is a system mortar. [0010] For this reason, it is possible to achieve both the improvement of the adhesion strength of the ceramic tube and the maintenance of the thermal shock resistance by using metaphysic cement and fiber-based mortar.

[0011] In addition, the metal filtration device of the present invention according to claim 3 of the present invention is similar to the metal filtration device of claim 1 or claim 2, and the fixing strength of the hot-water-side refractory is that of the ceramic tube. It is characterized by being one-half to one-third of the tensile strength.

[0012] For this reason, it is possible to achieve both improvement of the fixing strength of the ceramic tube and maintenance of thermal shock resistance while preventing destruction of the ceramic tube.

[0013] Further, the metal filtration device according to claim 4 of the present invention is the metal filtration device according to any one of claims 1 to 3, wherein the cleaning gas is jetted toward the ceramic tube. The gas jetting means is provided at the bottom of the unit container.

[0014] This makes it possible to achieve both improvement of the fixing strength of the ceramic tube and maintenance of thermal shock resistance even when repeated rapid temperature changes due to the ejection of the cleaning gas are repeated.

[0015] In addition, the metal filtration device according to claim 5 of the present invention is the metal filtration device according to any one of claims 1 to 4, wherein the ceramic tube is a ceramic tube made of an alumina porous tube. It is characterized by being.

[0016] Therefore, the molten metal can be filtered using a ceramic tube made of an alumina porous tube.

[0017] To achieve the above object, a filter cassette according to claim 6 of the present invention comprises a hot water side plate and a hot water side plate, an elongated shape with one end opened and the other end bottomed, The ceramic tube is attached to the hot water side plate and the other end is attached to the hot water side plate. The open end of the ceramic tube is attached to the hot water side plate with the hot water side refractory material, and the bottom of the ceramic tube is attached. The end of the pipe side is attached to the hot water supply side plate with the hot water side refractory material, and the fixing strength of the hot water side refractory is higher than the tensile strength of the ceramic tube, and the hot water side refractory is lower than the tensile strength of the ceramic tube. It is characterized by that.

[0018] For this reason, the open end of the ceramic tube is attached to the outlet side plate on the outlet side with a tapping refractory material having an adhesion strength higher than the tensile strength of the ceramic tube, so that the adhesion strength is maintained and the temperature is maintained. There is no gap even if expansion or contraction occurs due to change. Mixing of natural objects is suppressed, and expansion and contraction due to vibrations and temperature changes occur on the bottomed side of the ceramic tube attached to the hot-water side plate with a hot-water-side refractory material that has a lower bond strength than the tensile strength of the ceramic tube. Absorbed on the edge side. For this reason, it is possible to achieve both improvement of the fixing strength of the ceramic tube and maintenance of thermal shock resistance even if it is repeatedly subjected to vibrations and sudden temperature changes.

The invention's effect

[0019] The metal filtration device of the present invention is a metal filtration device and a filter cassette capable of achieving both improvement in the fixing strength of the ceramic tube and maintenance of thermal shock resistance even when repeatedly subjected to vibration and sudden temperature changes. .

Brief Description of Drawings

FIG. 1 is a side sectional view of a metal filtering device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a filter cassette.

FIG. 3 is a detailed view of essential parts in FIG. 2.

[Fig. 4] A table showing the results of construction conditions.

FIG. 5 is a table showing the fracture strength of refractory materials and ceramic tubes.

[Fig. 6] A table showing the physical properties of the refractory material.

FIG. 7 is an explanatory diagram of a load test.

FIG. 8 is an explanatory diagram of an impact test.

FIG. 9 is an explanatory diagram of an impact test.

FIG. 10 is a table showing the results of an impact test.

BEST MODE FOR CARRYING OUT THE INVENTION

[0021] FIG. 1 is a side cross-sectional view of a metal filtering device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a filter cassette, FIG. 3 is a detailed state of a main part in FIG. 2, and FIG. The result of the condition is shown. Fig. 5 shows the fracture strength of the refractory material and ceramic tube, Fig. 6 shows the physical properties of the refractory material, Fig. 7 shows the load test, Figs. 8 and 9 show the impact test, and Fig. 10 shows the impact. The results of the test are shown.

As shown in FIG. 1, the metal filtering device 1 is provided with a filter cassette 3 in a unit container 2, and the filter cassette 3 is held between a front inner wall 4 and a rear inner wall 5 via a wedge 6. Has been. The unit container 2 on the front inner wall 4 side is provided with a hot water inlet 7, and a molten metal (for example, molten aluminum) is supplied from the hot water inlet 7.

[0023] The unit container 2 on the opposite side of the filter cassette 3 across the rear inner wall 5 is provided with a tapping chamber 8, and the tapping chamber 8 is provided with a tapping port 9. The aluminum melt supplied from the hot water inlet 7 is filtered through the filter cassette 3, sent to the hot water outlet 8, discharged from the hot water outlet 9, and sent to the bowl.

[0024] Further, at the bottom of the unit container 2, a cleaning gas jetting means 10 for jetting a cleaning gas of an inert gas (for example, an argon gas) toward the filter cassette 3 is provided. When the molten metal is filtered, foreign matter accumulates near the surface of the ceramic tube, which will be described later, of the filter cassette 3, and clogging occurs due to long-term use. Therefore, clogging of the ceramic tube is suppressed by intermittently injecting a cleaning gas such as an inert gas from the cleaning gas ejection means 10.

[0025] The filter cassette 3 includes a pair of side plates 11 (a hot water side plate) and 12 (a hot water side plate). The front inner wall 4 holds the side plate 11 via a wedge 6, and the rear inner wall 5 has a packing. The side plate 12 is held via Side plates 11 and 12 are formed of silicon carbide refractory plates. There may be one between the side plates 11 and 12, but usually, a plurality of (e.g., 18 in four stages) long ceramic tubes 14 are provided, and the ceramic tubes 14 are made of an alumina porous tube. It is formed with. The ceramic tube 14 is made of alumina or silicon carbide. From the viewpoint of hot strength and aluminum resistance, ceramic tubes made of alumina porous tube are preferred!

As shown in FIGS. 2 and 3, the ceramic tube 14 has one end 14a open and the other end 14b bottomed. An insertion hole 15 is formed in the side plate 11, and the other end 14 b of the ceramic tube 14 is fitted into the insertion hole 15 through a ceramic fiber packing 16. On the other hand, the side plate 12 is formed with a hole 17 connected to the tapping chamber 8 (see FIG. 1), and one end 14a of the ceramic tube 14 is fitted to the hole 17 via a knock 13 corresponding to the hole 17.

As shown in FIG. 3, at both ends of the ceramic tube 14 having a diameter of Dmm, the width of the thickness S of the packings 13 and 16 is defined as the axial extension allowance. Further, the end of the ceramic tube 14 has a length of the gap R held by the side plates 11 and 12, and the side plate 12 and the ceramic tube are surrounded around the portion of the gap R. Refractory material for fixing the tube 14 is interposed.

[0028] The other end 14b of the ceramic tube 14 is attached to the side plate 11 by a fiber-based mortar 21 as a hot water-side refractory material. The fiber mortar 21 has elasticity and can absorb the expansion / contraction of the ceramic tube 14. One end 14a (the outlet side of the filtered molten metal) of the ceramic tube 14 is fixed to the side plate 12 by a refractory segment 22 as a refractory side refractory material. The refractory cement 22 does not cause a gap even when the ceramic tube 14 with high fixing strength expands and contracts, and it is not broken like a fiber mortar by vibration.

[0029] As shown in FIG. 5, the fiber-based mortar 21 has a weak adhesive force, which is less than 1S, for example, lOOkgf. In addition, the tensile breaking load (tensile strength) of the ceramic tube 14 is, for example, 200 kgf to 300 kgf, and the fixing strength of the fiber system mortar 21 is one half to one third of the tensile breaking load of the ceramic tube 14. It is preferred from the viewpoint of ensuring thermal shock resistance.

[0030] The fiber-based mortar 21 contains a ceramic fiber and an inorganic binder, and is an alumina silica-based ceramic fiber as the ceramic fiber. Furthermore, for example, 10 wt% to 20 wt% of ceramic fiber is contained, and as shown in FIG. 6, the total content of alumina (Al 2 O 3) is 80% or more and silica (SiO 2) is 10% or more.

2 3 2

Further, as shown in FIG. 5, the refractory cement 22 is a force (adhesion strength) force until destruction of the bonded portion, for example, 800 kgf, and has a strong adhering force. The refractory cement 22 is preferably a refractory cement having a fine aggregate particle size. Further, as shown in FIG. 6, alumina (Al 2 O 3) is 60

twenty three

Preferred is a refractory cement with about% and silica (SiO 2) about 40%.

2

[0032] Further, as shown in FIG. 6, the compressive strength of the fiber-based mortar 21 is, for example, l kgfZcm ² after treatment at room temperature and 800 ° C. Furthermore, the compressive strength of the refractory cement 22, for example, a LOOkgfZcm ² at room temperature, and One Do the 200KgfZcm ² after treatment 800 ° C.

[0033] The compressive strength of the side plate 12 (the hot water side plate) is higher than the compressive strength of the side plate 11 (the hot water side plate). It is also preferable to have a viewpoint that prevents breakage of the ceramic tube 14 and the detachment of the ceramic tube 14 from the side plates 11 and 12. That is, when the compressive strength of the side plate 11 is low, fluctuations in the length direction (axial direction) due to thermal variations of the ceramic tube 14 can be absorbed at that portion, and when the compressive strength of the side plate 12 is high, the side of the outlet side The ceramic tube 14 can be prevented from coming off. The preferable values are 2 to 30 kgfZcm ² (room temperature) and 50 to ²⁰⁰ kgfZcm ² (room temperature), respectively.

The load test having the value shown in FIG. 5 was performed using the test apparatus shown in FIG. That is, the test piece 101 (ceramic tube) having a diameter of Dlmm (for example, 100 mm) was held on the holding portion 103 of the end plate 102 (side plate: refractory plate), and the periphery of the test piece 101 was fixed with the refractory material 104. The diameter of the holding part 103 is D2 mm (for example, 104 mm), the holding length of the test piece 101 is R mm (for example, 26 mm), and the end of the test piece 101 has a thickness of Smm (for example, 4 mm). Packing 105 is interposed. In this state, a load was applied to the test piece 101, and the force until failure was measured.

[0035] When the refractory cement 22 is used as the refractory material, the fixing strength of the fiber mortar 21 which is stronger than that of the fiber mortar 21 is 2 minutes of the tensile breaking load of the ceramic tube 14. One-third to one-third. The fixing strength of the refractory cement 22 is 2 to 4 times or more of the tensile strength of the ceramic tube 14, and the fixing strength of the refractory cement 22 is 8 or more times that of the fiber-based mortar 21. . This is because the refractory cement 22 and the ceramic tube 14 are firmly fixed, and when a strong force is applied, the ceramic tube 14 is damaged before the attachment portion is detached. Further, since the fixing force of the fiber system mortar 21 is weak, the ceramic tube 14 is not damaged when the force is applied, and the bonded portion is damaged.

[0036] The fiber-based mortar 21 and the refractory cement 22 increase in fracture strength as the coating amount increases. The coating amount of the fiber-based mortar 21 needs about 20-30g to obtain the breaking strength of lOOkgf, and the fiber-based mortar 21 of about 20-30g at maximum is required to obtain the breaking strength lower than lOOkgf. Used. The amount of refractory cement 22 applied is about 40-50 g in order to obtain a breaking strength of 800 kgf, and about 40-50 g of refractory cement 22 is used to obtain a breaking strength of 800 kgf.

[0037] The result of the impact test in the case of the ceramic tube 14 having the same size as the test piece 101 This will be described with reference to FIGS.

[0038] As shown in FIG. 8, using a test arm in which a piece of wood 112 is attached to the tip of an arm 111 having a length L, the arm 111 is rotated by a head HI, and is repeatedly applied to the ceramic tube 14 by the piece of wood 112. Had a blow. As shown in FIG. 9, the part to which the impact is applied by the piece of wood 112 is also the part where the ceramic tube 14 is fixed to the holding part 114 by the refractory material 113 and the part H2 (for example, 100 mm) away in the axial direction. As shown in Fig. 10, when the refractory material 113 on both sides was a fiber-based mortar, significant wear was observed after 600 hits. When the refractory material 113 on the side close to the striking site (left side in Fig. 9) was made of refractory cement, it was strong enough to show no wear after 1200 hits.

Therefore, by attaching the ceramic tube 14 to the side plate 11 with the fiber-based mortar 21 and fixing the ceramic tube 14 to the side plate 12 with the refractory cement 22, a structure free from wear against vibration can be obtained.

In the metal filtration device 1 described above, the molten aluminum supplied from the hot water inlet 7 into the filter cassette 3 passes through a complicated flow path formed by a plurality of ceramic tubes 14, and Outer surface force It is sent to the inside of the cylinder and filtered to remove inclusions. The aluminum melt, which has been filtered and cleaned, is sent from the opening of one end 14a of the ceramic tube 14 to the hot water discharge chamber 8 through the hole 17 and discharged from the hot water outlet 9.

[0041] Inclusions removed during the filtration accumulate on the surface layer of the ceramic tube 14, and when filtration of the molten aluminum is repeated, the inclusions accumulated on the surface layer of the ceramic tube 14 can secure a predetermined flow rate. Disappear. For this reason, the filter cassette 3 is washed every predetermined period. When cleaning the filter cassette 3, cleaning gas (argon gas) is supplied from the cleaning gas ejection means 10 at a predetermined pressure. Argon gas becomes a large number of minute bubbles to remove inclusions deposited on the surface layer of the ceramic tube 14 and lift the inclusions.

[0042] When argon gas is blown in, the temperature of the molten aluminum decreases, and when the argon gas is stopped, the temperature of the molten aluminum increases. For this reason, the ceramic tube 14 repeatedly expands and contracts due to temperature changes. [0043] The other end 14b of the ceramic tube 14 is attached to the refractory plate 11 by an elastic fiber mortar 21. Therefore, the expansion and contraction of the ceramic tube 14 is absorbed by the mounting portion of the refractory plate 11. The For this reason, even if the ceramic tube 14 expands and contracts, there is no risk of cracking.

[0044] On the other hand, since one end 14a of the ceramic tube 14 is fixed to the fireproof plate 12 by the fireproof cement 22, the fixing strength is high, and even if the ceramic tube 14 expands and contracts, there is no gap in the fixing portion. In addition, the refractory cement 22 is not destroyed by vibration. For this reason, the fixed portion is not eroded on the outlet side of the molten aluminum, and inclusions are not generated, and the opening force of the one end 14a of the ceramic tube 14 does not cause the inclusions to enter.

[0045] Therefore, there is no possibility that a gap is generated on the outlet side that affects the filtration quality, that is, the ceramic tube 14 is firmly fixed to the fireproof plate 12 at one end 14a of the ceramic tube 14, and the gap is not generated. The expansion and contraction of the ceramic tube 14 is absorbed by the mounting portion of the refractory plate 11 at the other end 14b through the fiber mortar 21.

[0046] Therefore, in the metal filtration device 1 described above, it is possible to achieve both improvement in the fixing strength of the ceramic tube 14 and maintenance of the thermal shock resistance even when repeated sudden temperature changes are received.

[0047] As shown in FIG. 4, one end 14a of the ceramic tube 14 is fixed to the fireproof plate 12 with a fireproof cement 22, and the other end 14b of the ceramic tube 14 is attached to the fireproof plate 12 with a fiber mortar 21. In this case, there was no gap on the outlet side, and a good result (◯) was obtained, the impact resistance was excellent, and no crack was generated, and the result (◯) was obtained.

[0048] When both ends of the ceramic tube 14 are attached to the refractory plates 11 and 12 with the fiber-based mortar 21, the result is that the gap on the outlet side becomes too large (X), resulting in impact resistance. As a result, no crack was generated, and the result was (◯).

[0049] Further, when both ends of the ceramic tube 14 are attached to the refractory plates 11 and 12 with the refractory cement 22, there is no gap on the outlet side and a good result (◯) is obtained, and a crack is generated in terms of impact resistance. The result (X) was difficult.

[0050] As can be seen from the resultant force of FIG. 4, in this embodiment, it is understood that both the improvement of the fixing strength of the ceramic tube and the maintenance of the thermal shock resistance can be achieved even when repeated rapid temperature changes are performed. . Industrial applicability

INDUSTRIAL APPLICATION This invention can be utilized in the industrial field | area of the metal filtration apparatus and filter cassette which filter a molten metal.

Claims

The scope of the claims

[1] A metal filtering device having a hot water outlet and a hot water outlet,

A hot water side plate and a hot water side plate provided inside,

A ceramic tube with one end opened and the other end in a long shape with a bottom, one end attached to the hot water side plate and the other end attached to the hot water side plate

With

Attach the open end of the ceramic tube to the tapping side plate with tapping refractory material, and attach the bottom end of the ceramic tube to the tapping side plate with tapping refractory.

Fixing strength of the refractory material on the hot water side is higher than the tensile strength of the ceramic tube, and fixing strength of the refractory material on the hot water side is lower than the bow I tension strength of the ceramic tube.

A metal filtration device characterized by that.

[2] In the metal filtration device according to claim 1,

A metal filtering device characterized in that the refractory material on the hot water side is refractory cement and the refractory material on the hot water side is a fiber mortar.

[3] In the metal filtration device according to claim 1 or claim 2,

The adhesion strength of the refractory material on the hot water side is considered to be one-half to one-third of the tensile strength of the ceramic tube.

A metal filtration device characterized by that.

[4] In the metal filtration device according to any one of claims 1 to 3,

A metal filtration apparatus comprising a cleaning gas jetting means for jetting a cleaning gas toward a ceramic tube at a bottom portion of a unit container.

[5] In the metal filtration device according to any one of claims 1 to 4,

The metal filter is characterized in that the ceramic tube is a ceramic tube made of an anoleminous porous tube.

[6] Hot spring side plate and hot water side plate,

A ceramic tube having one end open and a bottomed bottom, and one end attached to a hot water side plate and the other end attached to a hot water side plate With

Attach the opening end of the ceramic tube to the tapping side plate with the tapping side refractory material, and attach the bottom end of the ceramic tube to the tapping side plate with the tapping side refractory material.

A filter cassette characterized by that.