JPH0341533B2 - - Google Patents
Info
- Publication number
- JPH0341533B2 JPH0341533B2 JP58110983A JP11098383A JPH0341533B2 JP H0341533 B2 JPH0341533 B2 JP H0341533B2 JP 58110983 A JP58110983 A JP 58110983A JP 11098383 A JP11098383 A JP 11098383A JP H0341533 B2 JPH0341533 B2 JP H0341533B2
- Authority
- JP
- Japan
- Prior art keywords
- molten metal
- filtration
- filter
- main body
- passage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 229910052751 metal Inorganic materials 0.000 claims description 44
- 239000002184 metal Substances 0.000 claims description 44
- 238000001914 filtration Methods 0.000 claims description 42
- 238000000034 method Methods 0.000 claims description 5
- 239000011148 porous material Substances 0.000 claims description 4
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 239000003507 refrigerant Substances 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 230000006837 decompression Effects 0.000 description 2
- 239000006260 foam Substances 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000011819 refractory material Substances 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000003779 heat-resistant material Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000003566 sealing material Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Filtration Of Liquid (AREA)
- Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
- Manufacture And Refinement Of Metals (AREA)
Description
【発明の詳細な説明】 本発明は金属溶湯のろ過方法に関する。[Detailed description of the invention] The present invention relates to a method for filtering molten metal.
例えばコンピユータの補助記憶装置に使用され
る磁気デイスクのデイスク基体をアルミニウムで
作る場合、介在物の大きさは数μ以下であること
が要求されている。このように介在物が微小な高
品質の製品を製造するには、鋳塊の製造段階にお
いてそのアルミニウム溶湯に含まれる介在物を相
応に除去する必要がある。 For example, when the disk base of a magnetic disk used in an auxiliary storage device of a computer is made of aluminum, the size of inclusions is required to be several microns or less. In order to manufacture a high-quality product with such minute inclusions, it is necessary to appropriately remove the inclusions contained in the molten aluminum at the ingot manufacturing stage.
一般に介在物の除去のために、金属溶湯をフイ
ルターに通してろ過することが行われている。こ
のようなフイルターとしてポーラスチユーブフイ
ルター、セラミツクフオームフイルター等が使用
され、通常は溶湯の自重によつてフイルターを通
過させている。 Generally, in order to remove inclusions, molten metal is filtered through a filter. Porous tube filters, ceramic foam filters, etc. are used as such filters, and the molten metal is usually passed through the filter by its own weight.
しかしながら前述したような高品質を得るため
に気孔径の微小なフイルターを使用して通常の自
重方式によるろ過を行うには、溶湯ヘツドをかな
り高めねばならない。例えばアルミニウム溶湯で
１Kg/cm2のゲージ圧を必要とする場合には、通常
の自重方式によるろ過では溶湯ヘツドは４ｍ以上
となつてしまう。このためろ過器の深さがそれ相
応に深いものとされねばならず、設備上、安全性
等の面で障害となる。しかもデツドストツクが多
くなつて歩留りが悪くなり、フイルターのセツト
作業も非常に困難となる。またろ過に要する圧力
は、ろ過開始時の一時期にその後のろ過継続中に
おけるよりも大きな圧力を必要とするので、この
一時期の高い圧力を得るためにのみ溶湯ヘツドを
むやみに高めることは好ましいことではない。 However, in order to obtain the above-mentioned high quality, the molten metal head must be considerably increased in order to carry out filtration by the normal gravity method using a filter with a small pore size. For example, if a gauge pressure of 1 kg/cm 2 is required for molten aluminum, the molten metal head would be 4 m or more if filtered using the normal gravity method. Therefore, the depth of the filter must be made correspondingly deep, which poses an obstacle in terms of equipment and safety. Furthermore, the amount of dead stock increases, resulting in poor yield and making it extremely difficult to set the filter. In addition, the pressure required for filtration is greater at the beginning of filtration than during the subsequent period of filtration, so it is not desirable to increase the molten metal head unnecessarily just to obtain a high pressure during this period. do not have.
本発明の目的は、増々高品質化が要求される状
況に鑑み、上述した従来技術の問題点を解決する
のみならず、通常のろ過装置に僅かの改修を行う
ことで簡単にろ過性能（微小介在物のろ過能力）
を高め得るようになすろ過方法を提供することで
ある。 In view of the increasing demand for higher quality, the purpose of the present invention is not only to solve the problems of the prior art described above, but also to easily improve the filtration performance (microscopic inclusion filtration ability)
An object of the present invention is to provide a filtration method that can increase the
このために本発明は、金属溶湯の自重によるろ
過開始において高圧を必要とする一時期に、フイ
ルターの金属溶湯流出側に真空圧を付与すること
を特徴とする。 For this purpose, the present invention is characterized in that vacuum pressure is applied to the molten metal outflow side of the filter at a time when high pressure is required to start filtration due to the weight of the molten metal.
以下に図示した実施装置を参照して本発明のろ
過方法を更に詳しく説明する。 The filtration method of the present invention will be explained in more detail with reference to the implementation apparatus illustrated below.
第１図は本発明のろ過方法を実施せるろ過装置
を示している。このろ過装置は本体１内に金属溶
湯溜２、フイルター装置３、ろ過溶湯通路４が設
けてあり、溶湯溜２に通じる入口樋５およびろ過
溶湯通路４を流れて来たろ過溶湯をろ過装置から
流出させるための出口樋６が配備されている。 FIG. 1 shows a filtration apparatus capable of carrying out the filtration method of the present invention. This filtration device is provided with a metal molten metal reservoir 2, a filter device 3, and a filtered molten metal passage 4 in a main body 1, and filtered molten metal flowing through an inlet gutter 5 leading to the molten metal reservoir 2 and a filtered molten metal passage 4 is passed from the filtration device. An outlet gutter 6 is provided for drainage.
本体１はフランジ部１０によつて分割された下
部本体１１および蓋本体１２より構成され、蓋本
体１２にはさらにフランジ部１３により分割され
た蓋部分１４が設けてある。蓋本体１２および蓋
部分１４はそれぞれ下部本体１１に装脱可能とさ
れており、後述するフイルター装置３および減圧
容器本体３０のセツト作業を行えるようになつて
いる。これらの本体１の構成部分は何れも外板１
５内にアルミナ繊維耐火物等で作られた適当な断
熱耐火材よりなる層１６を積層して配備されてい
る。さらにろ過準備としてろ過装置内部を加熱し
且つその後のろ過作業時に溶湯を所要温度に維持
するために、耐火断熱層１６に加えて例えば電熱
ヒーター等の加熱装置１７が適当に配備されてい
る。下部本体１１には耐火断熱層１６の内側に耐
溶湯材よりなる層１８が積層配備されており、こ
れらによつて溶湯溜２およびろ過溶湯通路４が形
成されている。 The main body 1 is composed of a lower main body 11 and a lid main body 12 divided by a flange portion 10, and the lid main body 12 is further provided with a lid portion 14 divided by a flange portion 13. The lid main body 12 and the lid portion 14 are each removable from the lower main body 11, so that the filter device 3 and the vacuum container main body 30, which will be described later, can be set. All of these constituent parts of the main body 1 are the outer panel 1.
A layer 16 made of a suitable heat-insulating refractory material such as alumina fiber refractory material is laminated within the refractory layer 5 . Furthermore, in order to heat the inside of the filtration apparatus in preparation for filtration and to maintain the molten metal at a required temperature during subsequent filtration work, a heating device 17 such as an electric heater is appropriately provided in addition to the fireproof insulation layer 16. In the lower body 11, a layer 18 made of a molten metal resistant material is laminated inside a fireproof heat insulating layer 16, and a molten metal reservoir 2 and a filtered molten metal passage 4 are formed by these layers.
フイルター装置３はセラミツクフオームフイル
ター等の一般に溶湯金属ろ過に使用するもので、
ここでは数μの介在物を除去するために数十μ程
度の気孔径のものとされる（気孔径の1/10程度の
介在物が除去可能とみなされている）。このフイ
ルター装置３は耐溶湯材で作られた溶湯溜２の底
部に嵌着させてセツトされる。 The filter device 3 is a ceramic foam filter or the like that is generally used for filtration of molten metal.
Here, in order to remove inclusions of several microns, the pore diameter is about several tens of microns (inclusions of about 1/10 of the pore diameter are considered to be removable). This filter device 3 is fitted and set at the bottom of a molten metal reservoir 2 made of a molten metal resistant material.
ろ過溶湯通路４はフイルター装置３を通過した
溶湯を流すための通路であり、蓋部分１４の下側
に形成せる空間部１９に通じていて、ここから出
口樋６を通して流出させるようになつている。通
路４の最下部にはろ過装置外部へ通ずるドレン抜
き通路２０が形成され、ドレン抜き作業以外にお
いてこの通路２０は開閉装置２１によつて密閉で
きるようになされている。 The filtration molten metal passage 4 is a passage for flowing the molten metal that has passed through the filter device 3, and communicates with a space 19 formed on the lower side of the lid portion 14, from which the molten metal flows out through the outlet gutter 6. . A drain passage 20 leading to the outside of the filtration device is formed at the lowest part of the passage 4, and this passage 20 can be sealed by an opening/closing device 21 except when draining.
空間部１９内に本発明の特徴とする真空圧付与
のための減圧容器本体３０が装脱できるように配
備されるのである。この減圧容器本体３０は鉄等
の耐熱材で形成されたここでは吊鐘状のものであ
り、下端の開口縁部３０Ａを空間部１９の底面に
対して密着させて配置され、これにより通路４の
空間部１９に対する開口を包囲させるようにして
セツトされるようになつている。すなわち減圧容
器本体３０を第１図に示す如くセツトすることに
より、出口樋６への流通は遮断できるようになつ
ているのである。 In the space 19, a decompression container body 30 for applying vacuum pressure, which is a feature of the present invention, is removably installed. This decompression container main body 30 is formed of a heat-resistant material such as iron and has a bell-like shape, and is arranged with the opening edge 30A at the lower end in close contact with the bottom surface of the space 19, so that the passage 4 The opening to the space 19 is surrounded by the opening. That is, by setting the reduced pressure container main body 30 as shown in FIG. 1, the flow to the outlet gutter 6 can be blocked.
減圧容器本体３０は第２図に示す如く頂部にて
耐圧ホース３１により減圧タンク３２に接続さ
れ、この減圧タンク３２に接続された真空ポンプ
３３により減圧タンク３２を減圧されることで減
圧容器本体３０を通して通路４内を真空引きでき
るようになつている。耐圧ホース３１には冷却器
３４が介装され、その冷媒通路３５を流れる冷媒
との熱交換によつて冷却されるようになすことが
望ましい。何故ならば、後述するようにこの真空
引きは金属溶湯をフイルターに通すために行われ
るのであり、その熱気により高温ガスを真空引き
することになるからである。また耐圧ホース３１
には三方向弁３６を介装し、真空引きを迅速に停
止できるようにするのが望ましい。 As shown in FIG. 2, the reduced pressure container main body 30 is connected at the top to a reduced pressure tank 32 by a pressure hose 31, and the reduced pressure tank 32 is depressurized by a vacuum pump 33 connected to this reduced pressure tank 32, so that the reduced pressure container main body 30 The inside of the passage 4 can be evacuated through the passage 4. It is desirable that a cooler 34 is interposed in the pressure hose 31 so that the pressure hose 31 is cooled by heat exchange with the refrigerant flowing through the refrigerant passage 35 . This is because, as will be described later, this evacuation is performed to pass the molten metal through a filter, and the hot air is used to evacuate the high-temperature gas. Also, the pressure hose 31
It is preferable that a three-way valve 36 be interposed therein so that the evacuation can be quickly stopped.
このような構成のろ過装置によつてろ過を行う
場合、蓋本体１２を取外して所要のフイルター装
置３をセツトしておく。また減圧容器本体３０を
第１図に示す如く所定位置にセツトしておくとと
もに、真空ポンプ３３を作動して減圧タンクを所
要真空圧にしておく。 When performing filtration with a filtration device having such a configuration, the lid main body 12 is removed and the required filter device 3 is set. Further, the vacuum container main body 30 is set in a predetermined position as shown in FIG. 1, and the vacuum pump 33 is operated to bring the vacuum tank to the required vacuum pressure.
然る後ろ過すべき溶湯を入口樋５から溶湯溜２
へ供給する。この溶湯ヘツドをレベルl1で示す。
一方、出口樋６のレベルはl2であり、この差△ｌ
がろ過時の溶湯ヘツドとなる。勿論溶湯ヘツド△
ｌは予め必要とされる圧力を基にして設定されて
いるのである。 After that, the molten metal to be filtered is transferred from the inlet gutter 5 to the molten metal sump 2.
supply to This molten metal head is indicated by level l 1 .
On the other hand, the level of the outlet gutter 6 is l 2 , and this difference △l
becomes the molten metal head during filtration. Of course the molten metal head△
l is set in advance based on the required pressure.
しかるに、溶湯を溶湯溜２に供給してそれがフ
イルター装置３を通るまでは溶湯ヘツドはｈで示
されるように大きいが、フイルター装置３を最初
に通過する際には溶湯の表面張力によるろ過抵抗
が非常に大きく、この溶湯ヘツドｈでは不足す
る。この間に減圧容器本体３０を通じてフイルタ
ー装置３の出口側の通路４を負圧とし、この負圧
の助勢によりろ過を開始せしめるのである。一旦
ろ過が開始されると、図示例ではヘツド△ｌによ
つて連続してろ過が行われるので、負圧の付与は
不要となる。従つてろ過が開始されたならば速や
かに真空引きを停止し、減圧容器本体３０をろ過
装置から取出して蓋部分１４をセツトする。勿論
取出すことに代えて適当な距離につきろ過装置内
で持上げるように構成することもできる。 However, until the molten metal is supplied to the molten metal reservoir 2 and passes through the filter device 3, the molten metal head is large as shown by h, but when it first passes through the filter device 3, the filtration resistance due to the surface tension of the molten metal increases. is very large, and this molten metal head h is insufficient. During this time, the passage 4 on the outlet side of the filter device 3 is made negative pressure through the reduced pressure container main body 30, and filtration is started with the assistance of this negative pressure. Once the filtration is started, in the illustrated example, the filtration is performed continuously by the head Δl, so that it is not necessary to apply a negative pressure. Therefore, once filtration has started, the evacuation is immediately stopped, the reduced pressure container main body 30 is taken out from the filtration device, and the lid portion 14 is set. Of course, instead of taking it out, it can also be configured to be lifted up within the filtration device by a suitable distance.
ろ過終了に際しては開閉装置２１を開いてドレ
ン抜き通路２１から通路４内に溜つた溶湯を排出
する。然る後フイルター装置３の交換等の作業を
行つて次のろ過に待機される。 Upon completion of filtration, the opening/closing device 21 is opened to discharge the molten metal accumulated in the passage 4 from the drain passage 21. After that, operations such as replacing the filter device 3 are performed, and the filter device is placed on standby for the next filtration.
以上の如く本発明によれば金属溶湯のろ過に際
し、特に少くともろ過開始の一時期にフイルター
装置の出口側に真空圧を作用させることでろ過開
始のために必要な圧力を得るのであるから、自重
方式のろ過装置で溶湯ヘツドを高めることなくよ
り微細なフイルター装置によるろ過を可能とする
のである。従つて従来装置に僅かな改修を加える
だけでより高品質を得るろ過装置となし得るの
で、産業上極めて有利である。 As described above, according to the present invention, when filtering molten metal, the pressure necessary for starting filtration is obtained by applying vacuum pressure to the outlet side of the filter device at least for a period of time when filtration starts. This method enables filtration using a finer filter device without increasing the molten metal head. Therefore, it is possible to obtain a filtration device of higher quality by simply making a slight modification to the conventional device, which is extremely advantageous industrially.
尚図示実施装置は本発明の実施のための一例を
示すもので限定するものではない。従つて例えば
減圧容器本体の下端開口縁に沿つて耐熱パツキン
グ等のシール材を備えて真空引きの効率を高める
ようにすることができる。また図示例では減圧容
器本体３０に至る通路４を長くして（出口樋６を
高い位置とする）溶湯に接触しないようにしてあ
るが、このような通路構成は任意である。 It should be noted that the illustrated implementation apparatus shows an example for implementing the present invention, and is not intended to be limiting. Therefore, for example, a sealing material such as heat-resistant packing may be provided along the lower opening edge of the vacuum container main body to improve the efficiency of evacuation. Further, in the illustrated example, the passage 4 leading to the reduced pressure container main body 30 is made long (the outlet gutter 6 is set at a high position) so as not to come into contact with the molten metal, but such a passage configuration is arbitrary.
第１図は本発明のろ過方法を実施するために使
用するろ過装置の一実施例を示す断面図。第２図
は真空圧付与のための系統図。
１…本体、２…溶湯溜、３…フイルター装置、
４…通路、５…入口樋、６…出口樋、２０…ドレ
ン抜き通路、２１…開閉装置、３０…減圧容器本
体、３１…耐圧ホース、３２…減圧タンク、３３
…真空ポンプ、３４…冷却装置、３５…冷媒通
路、３６…三方向弁。
FIG. 1 is a sectional view showing one embodiment of a filtration device used to carry out the filtration method of the present invention. Figure 2 is a system diagram for applying vacuum pressure. 1... Main body, 2... Molten metal reservoir, 3... Filter device,
4...Passway, 5...Inlet gutter, 6...Outlet gutter, 20...Drain removal passage, 21...Opening/closing device, 30...Reduced pressure container body, 31...Pressure resistant hose, 32...Reduced pressure tank, 33
...Vacuum pump, 34...Cooling device, 35...Refrigerant passage, 36...Three-way valve.
Claims (1)
通してろ過するろ過方法において、少くともフイ
ルターに形成せる気孔を通して金属溶湯が最初に
フイルターを通過するろ過開始初期の一時期に、
フイルターの金属溶湯流出側に真空圧を作用させ
る段階を含むことを特徴とする金属溶湯のろ過方
法。1. In a filtration method in which inclusions contained in molten metal are filtered through a filter, at least during the initial stage of filtration when the molten metal first passes through the filter through pores formed in the filter,
A method for filtering molten metal, comprising the step of applying vacuum pressure to the molten metal outflow side of a filter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58110983A JPS605829A (en) | 1983-06-22 | 1983-06-22 | Filtering method of molten metal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58110983A JPS605829A (en) | 1983-06-22 | 1983-06-22 | Filtering method of molten metal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS605829A JPS605829A (en) | 1985-01-12 |
| JPH0341533B2 true JPH0341533B2 (en) | 1991-06-24 |
Family
ID=14549425
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58110983A Granted JPS605829A (en) | 1983-06-22 | 1983-06-22 | Filtering method of molten metal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS605829A (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0659532B2 (en) * | 1985-02-01 | 1994-08-10 | 住友電気工業株式会社 | Continuous casting equipment |
| JPS62218502A (en) * | 1986-03-17 | 1987-09-25 | Sumitomo Light Metal Ind Ltd | Treatment of molten metal for aluminum or aluminum alloy powder |
| CA2198301C (en) * | 1997-02-24 | 2004-09-14 | Alcan International Limited | Portable liquid metal filtration device for inclusion analysis |
| WO2005080028A1 (en) | 2004-02-24 | 2005-09-01 | Alcan International Limited | Method of priming filter for molten metal |
| WO2006110974A1 (en) * | 2005-04-21 | 2006-10-26 | Alcan International Limited | Method of priming filter for molten metal |
| WO2016126165A1 (en) * | 2015-02-06 | 2016-08-11 | Norsk Hydro Asa | Apparatus and method for the removal of unwanted inclusions from metal melts |
-
1983
- 1983-06-22 JP JP58110983A patent/JPS605829A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS605829A (en) | 1985-01-12 |
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