JPH01259101A - Manufacture of ferrous spherical particle - Google Patents
Manufacture of ferrous spherical particleInfo
- Publication number
- JPH01259101A JPH01259101A JP63085389A JP8538988A JPH01259101A JP H01259101 A JPH01259101 A JP H01259101A JP 63085389 A JP63085389 A JP 63085389A JP 8538988 A JP8538988 A JP 8538988A JP H01259101 A JPH01259101 A JP H01259101A
- Authority
- JP
- Japan
- Prior art keywords
- powder
- flame
- iron
- ferrous
- oxygen
- 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.)
- Granted
Links
- 239000012798 spherical particle Substances 0.000 title claims abstract description 9
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 7
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 title abstract 9
- 239000000843 powder Substances 0.000 claims abstract description 34
- 239000007789 gas Substances 0.000 claims abstract description 8
- 239000011261 inert gas Substances 0.000 claims abstract description 7
- 238000002485 combustion reaction Methods 0.000 claims abstract description 5
- 238000002844 melting Methods 0.000 claims abstract description 4
- 230000008018 melting Effects 0.000 claims abstract description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 67
- 229910052742 iron Inorganic materials 0.000 claims description 24
- 239000002245 particle Substances 0.000 claims description 3
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 abstract description 24
- 238000000034 method Methods 0.000 abstract description 23
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 abstract description 20
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 15
- 239000001301 oxygen Substances 0.000 abstract description 15
- 229910052760 oxygen Inorganic materials 0.000 abstract description 15
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 abstract description 13
- 239000001294 propane Substances 0.000 abstract description 10
- 229910001873 dinitrogen Inorganic materials 0.000 abstract description 9
- ATRMIFNAYHCLJR-UHFFFAOYSA-N [O].CCC Chemical compound [O].CCC ATRMIFNAYHCLJR-UHFFFAOYSA-N 0.000 abstract description 5
- 238000002347 injection Methods 0.000 abstract description 4
- 239000007924 injection Substances 0.000 abstract description 4
- 230000003647 oxidation Effects 0.000 abstract description 4
- 238000007254 oxidation reaction Methods 0.000 abstract description 4
- 238000001816 cooling Methods 0.000 abstract description 3
- 239000000446 fuel Substances 0.000 description 6
- 238000007796 conventional method Methods 0.000 description 4
- 239000010935 stainless steel Substances 0.000 description 4
- 229910001220 stainless steel Inorganic materials 0.000 description 4
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 125000002534 ethynyl group Chemical group [H]C#C* 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000012299 nitrogen atmosphere Substances 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 239000012298 atmosphere Substances 0.000 description 2
- 239000012159 carrier gas Substances 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 241001062472 Stokellia anisodon Species 0.000 description 1
- LNSPFAOULBTYBI-UHFFFAOYSA-N [O].C#C Chemical group [O].C#C LNSPFAOULBTYBI-UHFFFAOYSA-N 0.000 description 1
- 239000003570 air Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910002090 carbon oxide Inorganic materials 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 238000005238 degreasing Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000002737 fuel gas Substances 0.000 description 1
- NPEWZDADCAZMNF-UHFFFAOYSA-N gold iron Chemical compound [Fe].[Au] NPEWZDADCAZMNF-UHFFFAOYSA-N 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000007517 polishing process Methods 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 238000006722 reduction reaction Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
Landscapes
- Powder Metallurgy (AREA)
Abstract
Description
【発明の詳細な説明】
「産業上の利用分野］
本発明は、鉄系球状粒子の製造方法に関するものである
。DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to a method for producing iron-based spherical particles.
［従来の技術］
鋼材の溶断、粉末冶金、化学還元などにおいて使用され
る鉄系の粉末は、鉄系素材を粉砕し篩分する方υ、によ
っていたか、粉末の流動性や製品品質の向上を狙うため
、粉砕粉に代わって、球状の粉末か要求されてき“（い
る。鉄系の球状粒子の製造方法は、特開昭５０− ］
’ｌ Ｉｉ ５６１に記載されるように、１０ ［１ｆ
ｌ−１４０［］°Ｃの雰囲気に鉄粉を投入し、鉄粉な酸
化燃焼させその熱によって、鉄粉を溶融し、球状化する
ことか知られている。しかしなから、この方法では、投
入する鉄粉末か過度に酸化するため、球状化した鉄粉の
周囲に醇化鉄層か生成する欠点を有している。[Conventional technology] Iron-based powders used in steel cutting, powder metallurgy, chemical reduction, etc. have been produced by crushing and sifting iron-based materials, or by improving powder fluidity and product quality. In order to achieve
'l Ii 561, 10 [1f
It is known that iron powder is put into an atmosphere at 1-140 []°C, and the iron powder is oxidized and burned, and the heat melts the iron powder and turns it into spheres. However, this method has the disadvantage that the iron powder to be introduced is excessively oxidized, resulting in the formation of a liquefied iron layer around the spheroidized iron powder.
［発明か解決しようとする課題と解決手段コ上記の公知
技術ては、鉄系球状粒子の製造は、可能であるか粒子の
周辺に、酸化鉄か生成するため、その酸化鉄を還元し゛
Ｃ金屈鉄とする工程を必要とする。[Problems to be Solved by the Invention and Solution] Is it possible to produce iron-based spherical particles using the above-mentioned known technology?Since iron oxide is generated around the particles, the iron oxide is reduced (C). It requires a process to make it into gold iron.
発明者等は、このような上記従来技術の欠点を解消する
ため、火炎中に破砕状または、繊維状の鉄系粉末を不活
性ガスと共に投入し、火炎中て球状化させる方法を見出
した。すなわち、公知例ては、鉄粉末日体を酪素によっ
て酸化燃焼させるため、当然のことなから、粒子の周囲
に酸化鉄層を生成する。これに対し、本発明法ては、鉄
系粉末を溶融させる熱源は、酸素、空気、プロパン、ア
セチレンなと気体燃料によっているため、鉄粉の過剰な
酸化かおこり難い。さらに、本発明では、鉄粉末を不活
性ガスと一緒に火炎中に投入するため、酸化鉄の生成を
、ざらに防ＩＬすることか可能である。In order to overcome the drawbacks of the above-mentioned conventional techniques, the inventors have discovered a method of injecting crushed or fibrous iron-based powder into a flame together with an inert gas and spheroidizing it in the flame. That is, in the known example, since iron powder is oxidized and burned with butyric, an iron oxide layer is naturally formed around the particles. In contrast, in the method of the present invention, the heat source for melting the iron-based powder is a gaseous fuel such as oxygen, air, propane, or acetylene, so that excessive oxidation of the iron powder is unlikely to occur. Furthermore, in the present invention, since the iron powder is thrown into the flame together with the inert gas, it is possible to roughly prevent the production of iron oxide.
この方法によれは、鉄系粉末を溶融させるための熱源は
、気体燃料を使用するため、公知例のような鉄粉末の燃
焼による酸化鉄層を生成することはない。しかも、酸素
−プロパンや酸素−アセチレン噴出孔と鉄系粉末噴出孔
とか独立し、鉄系粉末は、専用のｎｐ出出孔ら不活性ガ
スと一緒に噴出するため、その粉末の溶融に際し、酸化
現象が一層起こりにくｕ・。このような本発明法によれ
は、鉄系粉末か火炎中て溶融し１表面張力によって完全
に球状化し、冷却過程て鉄系の球状粒子か得られること
になる。According to this method, a gaseous fuel is used as a heat source for melting the iron-based powder, so an iron oxide layer is not generated due to combustion of the iron powder as in the known example. Moreover, the oxygen-propane or oxygen-acetylene nozzle and the iron-based powder nozzle are independent, and the iron-based powder is ejected together with inert gas from the dedicated NP nozzle, so when the powder is melted, it is oxidized. The phenomenon is even more unlikely to occur. According to the method of the present invention, iron-based powder is melted in a flame, completely spheroidized by surface tension, and iron-based spherical particles are obtained during the cooling process.
次に、本発明法を図面に基づいて詳細に説明する。Next, the method of the present invention will be explained in detail based on the drawings.
第１図ε；ｌ、本発明法による鉄系球状杓子の製造方法
の概略図である。バーナ１の正面は、第２１２１に示す
ように火炎孔１０と鉄系粉末噴出孔］１かサントウィチ
状に円周状に配列されている。バーナ１からは、例えは
酸素−プロパン火炎２と＃：系粉末３か噴出する。鉄
系粉末３は、ホッパー５に貯蔵されており、窒素ガス９
とともにパイプ（又はホース）４を通してバー・３−に
入り、噴出する。−方、火炎を生成する酸素６、プロパ
ン（又はアセチレン）７か、ガス制御器８を経由してバ
ーナｌに入り、酸素−プロパンの混合気体となり、火炎
孔１０より噴出し、火炎を生成する。形成した火炎２の
熱により窒素ガスとともに噴出した鉄系粉末３か溶融し
、表面張力によって球状化する。冷却凝固後、鉄系粉末
を回収することによって大部の球状化鉄粉を得ることか
てきる。FIG. 1 is a schematic diagram of a method for manufacturing an iron-based spherical ladle according to the method of the present invention. On the front side of the burner 1, flame holes 10 and iron-based powder ejection holes] 1 are arranged circumferentially in a sandwich pattern, as shown in numeral 2121. For example, an oxygen-propane flame 2 and #: type powder 3 are ejected from the burner 1. Iron-based powder 3 is stored in a hopper 5, and nitrogen gas 9
Along with this, it enters the bar 3- through the pipe (or hose) 4 and is ejected. - On the other hand, the oxygen 6 and propane (or acetylene) 7 that generate the flame enter the burner l via the gas controller 8, become a mixed gas of oxygen and propane, and are ejected from the flame hole 10 to generate a flame. . The iron-based powder 3 ejected together with the nitrogen gas is melted by the heat of the formed flame 2 and becomes spheroidized by surface tension. After cooling and solidifying, most of the spheroidized iron powder can be obtained by recovering the iron-based powder.
このプロセスにおい゛Ｃ，鉄系粉末は、窒素ガスととも
に噴出し、鉄粉の醇化防止か図れるか、望ましくは、燃
料である酸素−プロパンの燃焼比率を（理論的には、酸
素／プロパン−５）を小さくし、出来るたけ、渦剰耐素
を少なくすることか酸化防止をさらに高める上て重要で
ある。In this process, the iron-based powder is ejected together with nitrogen gas, and it is possible to prevent the iron powder from becoming smelt or, desirably, to increase the combustion ratio of the oxygen-propane fuel (theoretically, the oxygen/propane-5 ), it is important to reduce the vortex resistance as much as possible, or to further increase the oxidation prevention.
［実施例］
実施例１
鋼材の溶断用として使用している粉砕鉄粉を従来法、す
なわち、鉄粉を酸素によって酸化燃焼させる技術と比較
して調査した。本発明法ては、燃料に酸素とプロパンを
、鉄粉のキャリヤーガスに窒素ガスを使用し、鉄粉の火
炎ｌ＼の供給速度を８０Ｋｇ／ｈｒとした。その結果を
第１表に示した。[Examples] Example 1 The crushed iron powder used for cutting steel materials was investigated by comparing it with a conventional method, that is, a technique in which iron powder is oxidized and burned with oxygen. In the method of the present invention, oxygen and propane were used as fuel, nitrogen gas was used as a carrier gas for the iron powder, and the supply rate of the iron powder flame was 80 kg/hr. The results are shown in Table 1.
第１表
ここて、本発明法のプロパン量と酸素届は、プロパン１
５Ｎｍ”／ｈｒ一定とし、酸素の量を７５．６０．４５
Ｎｍ″／ｈｒと変化させ、酸素／プロパン比か５．４．
３となるようにした。また、キャリヤーガスとしての窒
素は、７ Ｎｍ３／ｈｒの−・定として実施した。第１
表から明らかなように、従来法ては、鉄粉末自体は、球
状化するか、その表面に３０〜４０％の酸化鉄か発生ず
る。これに対し、本発明法ては、酸素／プロパン比か５
の時、３・〜４％の酸化鉄か発生ずるのみて、その比か
４．３の時は、全く発生しない。これは、本発明法ては
、溶融した球状粒子か酸素と反応しにくいことを示して
おり、従来法の鉄粉末を酸素によって酸化燃焼させる技
術とは、各段に差が認められる。Table 1 Here, the amount of propane and the amount of oxygen for the method of the present invention are as follows: propane 1
5Nm”/hr constant, oxygen amount 75.60.45
Nm″/hr, and the oxygen/propane ratio was 5.4.
I set it to 3. Further, nitrogen as a carrier gas was used at a constant rate of 7 Nm3/hr. 1st
As is clear from the table, in the conventional method, the iron powder itself becomes spheroidized or 30 to 40% iron oxide is generated on its surface. In contrast, in the method of the present invention, the oxygen/propane ratio is
When the ratio is 4.3, only 3-4% iron oxide is generated, and when the ratio is 4.3, no iron oxide is generated at all. This indicates that the method of the present invention is less likely to react with oxygen due to the molten spherical particles, and is clearly different from the conventional method of oxidizing and burning iron powder with oxygen.
実施例２
ステンレス鋼板の研磨工程て発生ずる削り粉を脱脂後、
粉砕し、流動性を高めてから、実施例１と同様のテスト
を行なった。テスト条件は、・実施例１と同一であるか
、今回は、実施例１に、さらに、火炎全体を窒素ガス雰
囲気て覆って実施した。比較としては、実施例１の火炎
を窒素ガスて覆わない方法と比較した。第２表にその結
果を示す。Example 2 After degreasing the shavings generated during the polishing process of stainless steel plate,
After pulverizing and increasing fluidity, the same test as in Example 1 was conducted. The test conditions were the same as in Example 1.This time, in addition to Example 1, the test was conducted by covering the entire flame with a nitrogen gas atmosphere. For comparison, a comparison was made with the method of Example 1 in which the flame was not covered with nitrogen gas. Table 2 shows the results.
第２表
窒素雰囲気の条件としては、火炎全体を円筒状の＋１Ｙ
Ｆｔ人物で覆い、その円部物の内部に窒素ガスを、Ｉ
Ｎ ｍ ” ／ ｈ ｒ吹込なから実施した。Table 2 The conditions for the nitrogen atmosphere are as follows:
Ft covered with a figure, nitrogen gas inside the circular part, I
It was carried out starting from the injection of Nm''/hr.
第２表より明らかなように、窒素雰囲気下てのテストに
よって得たステンレスの球状粉は、酸化率か１％耕下と
少ない。このことから、火炎を窒素雰囲気で覆うことて
、ざらに、酸化鉄の少ない球状粉か冑られることか判る
。As is clear from Table 2, the oxidation rate of the stainless steel spherical powder obtained by the test under the nitrogen atmosphere was as low as 1%. From this, it can be seen that covering the flame with a nitrogen atmosphere roughly destroys the spherical powder with less iron oxide.
［発明の効果］
実施例１．２て述へたように、本発明法によれは、鉄粉
およびステンレス粉か、容易に球状化てき、しかも、従
来技術て発生したような、酸化鉄の発生率か極めて少な
い球状法☆子をｍることかてきる。本発明法で、使用で
きる材料粉末は、鉄粉、ステンレス粉に限らず、高温で
酸化されやずい鉄系の粉末であれば、あらゆる合金粉末
も使用することかできる。[Effects of the Invention] As described in Example 1.2, the method of the present invention allows iron powder and stainless steel powder to easily become spheroidized, and moreover, does not cause iron oxide to form, which occurs with the prior art. The occurrence rate is extremely low, and it can be said that the spherical method ☆ child is m. In the method of the present invention, the material powder that can be used is not limited to iron powder or stainless steel powder, but any alloy powder can be used as long as it is an iron-based powder that is oxidized at high temperatures.
さらに、燃料は、支燃用として、酸素以外に、酸素と窒
素の混合物でも十分使用することができる。一方、燃料
ガスとしては、プロパン、アセチレン等炭化水素系のガ
スや水素、−酸化炭素等の気体燃料であれば、それらを
、単独又は混合してイ吏用することができる。Furthermore, in addition to oxygen, a mixture of oxygen and nitrogen can also be used as a fuel for supporting combustion. On the other hand, the fuel gas may be a hydrocarbon gas such as propane or acetylene, or a gaseous fuel such as hydrogen or carbon oxide, either alone or in combination.
第１図は本発明法による鉄系球状粒子の製造方法の一実
施例を示す概略説明図、第２図は第１図におけるバーナ
の正面説明図である。
１・・・バーナ、２・・・火炎、３・・・鉄系粉末、４
゜６．７・・・パイプ、５・・・ポツパー、８・・・ガ
ス制御回路、９・・・窒素ガス、１０・・・火炎孔、１
１・・・粉末噴射孔。FIG. 1 is a schematic explanatory diagram showing an embodiment of the method for producing iron-based spherical particles according to the method of the present invention, and FIG. 2 is a front explanatory diagram of the burner in FIG. 1. 1...Burner, 2...Flame, 3...Iron-based powder, 4
゜6.7... Pipe, 5... Popper, 8... Gas control circuit, 9... Nitrogen gas, 10... Flame hole, 1
1...Powder injection hole.
Claims (1)
、火炎中で鉄系粉末を溶融球状化させることを特徴とす
る鉄系球状粒子の製造方法。A method for producing iron-based spherical particles, which comprises introducing iron-based powder together with an inert gas into combustion flame gas and melting the iron-based powder into spheroidized particles in the flame.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63085389A JPH0692601B2 (en) | 1988-04-08 | 1988-04-08 | Method for producing iron-based spherical particles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63085389A JPH0692601B2 (en) | 1988-04-08 | 1988-04-08 | Method for producing iron-based spherical particles |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01259101A true JPH01259101A (en) | 1989-10-16 |
| JPH0692601B2 JPH0692601B2 (en) | 1994-11-16 |
Family
ID=13857394
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63085389A Expired - Fee Related JPH0692601B2 (en) | 1988-04-08 | 1988-04-08 | Method for producing iron-based spherical particles |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0692601B2 (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5022757A (en) * | 1973-07-03 | 1975-03-11 | ||
| JPS63111101A (en) * | 1986-10-30 | 1988-05-16 | Daido Steel Co Ltd | Spheroidizing method for metal or alloy powder |
| JPS63307203A (en) * | 1987-05-27 | 1988-12-14 | ジー・ティー・イー・プロダクツ・コーポレイション | Wet metallurgical method for producing finely divided or spherical metal powder |
-
1988
- 1988-04-08 JP JP63085389A patent/JPH0692601B2/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5022757A (en) * | 1973-07-03 | 1975-03-11 | ||
| JPS63111101A (en) * | 1986-10-30 | 1988-05-16 | Daido Steel Co Ltd | Spheroidizing method for metal or alloy powder |
| JPS63307203A (en) * | 1987-05-27 | 1988-12-14 | ジー・ティー・イー・プロダクツ・コーポレイション | Wet metallurgical method for producing finely divided or spherical metal powder |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0692601B2 (en) | 1994-11-16 |
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