CN102453832A - Preparation method of cast iron - Google Patents
Preparation method of cast iron Download PDFInfo
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- CN102453832A CN102453832A CN2010105264366A CN201010526436A CN102453832A CN 102453832 A CN102453832 A CN 102453832A CN 2010105264366 A CN2010105264366 A CN 2010105264366A CN 201010526436 A CN201010526436 A CN 201010526436A CN 102453832 A CN102453832 A CN 102453832A
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Abstract
The invention provides a preparation method of cast iron. The preparation method comprises the following steps of: (1) introducing blast furnace molten iron into a decarburization furnace to carry out decarburization treatment, so as to obtain cast iron liquid; (2) introducing the cast iron liquid into a steel ladle, introducing alloying raw material into the cast iron liquid, and alloying; and (3) introducing the alloyed cast iron liquid into a cast iron mould, and demoulding after cooling, so as to obtain the cast iron. According to the preparation method of cast iron provided by the invention, blast furnace molten iron is taken as raw material, decarburization and alloying are carried out, the cast iron with the required compositions can be obtained, the raw materials adopted in the method provided by the invention are easy to obtain, compositions are stable, requirements of cast iron production can be met, and energy consumption is obviously reduced as compared with that of an electric arc furnace smelting method, thus production cost is greatly reduced.
Description
Technical field
The present invention relates to a kind of preparation method of cast iron.
Background technology
Cast iron is meant a kind of steel casting that adopts castmethod and produce.Cast iron is mainly used in and makes that some are complex-shaped, be difficult to forge or cut is shaped and the intensity of having relatively high expectations and the part of plasticity.
In Cast Iron Production, electric arc furnace smelting is to use method the most widely.This method is to use solid charges such as steel scrap, and the high temperature and the heat energy that utilize electric arc to produce melt these solid charges, thereby realizes the purpose of smelting.The electric arc furnace smelting greatest problem is: the source of raw material steel scrap is unstable; And the complicated component of steel scrap; Not all steel scrap all is suitable for preparing cast iron, thereby makes the raw material of Cast Iron Production receive great restriction, in addition; In the process of melting waste steel, consume a large amount of electric energy, cause production cost too high.
Summary of the invention
The objective of the invention is to overcome the shortcoming that raw material sources are limited and cost is too high that the preparation method of existing cast iron exists, a kind of novel method for preparing cast iron is provided.
The invention provides a kind of preparation method of cast iron, wherein, this method comprises:
(1) is incorporated in the decarburization stove blast-melted, under oxygen supply condition, carries out carbonization treatment, obtain cast iron liquid;
(2) cast iron liquid is incorporated in the ladle, and in cast iron liquid, introduces the alloying raw material, and alloying;
(3) the cast iron liquid after the alloying is incorporated in the cast iron mould, the cooling back demoulding obtains cast iron;
Wherein, the condition of said carbonization treatment makes in the cast iron liquid that obtains, and the content of carbon is 2.5-3.5 weight %, and the content of sulphur is below the 0.08 weight %, and the content of phosphorus is below the 0.1 weight %.
The preparation method of cast iron provided by the invention is blast-melted as raw material through using; And, can access the cast iron of required composition through decarburization and alloying, the raw material sources of method provided by the invention are extensive; And stable components; Can satisfy the requirement of Cast Iron Production, and significantly reduce, reduce production cost widely with respect to its energy consumption of electric arc furnace smelting method.
Embodiment
The invention provides a kind of preparation method of cast iron, wherein, this method comprises:
(1) is incorporated in the decarburization stove blast-melted, under oxygen supply condition, carries out carbonization treatment, obtain cast iron liquid;
(2) cast iron liquid is incorporated in the ladle, and in cast iron liquid, introduces the alloying raw material, and alloying;
(3) the cast iron liquid after the alloying is incorporated in the cast iron mould, the cooling back demoulding obtains cast iron;
Wherein, the condition of said carbonization treatment makes in the cast iron liquid that obtains, and the content of carbon is 2.5-3.5 weight %, and the content of sulphur is below the 0.08 weight %, and the content of phosphorus is below the 0.1 weight %.
According to the present invention; The kind of said decarburization stove is conventionally known to one of skill in the art; The condition of said carbonization treatment can be adjusted according to the required carbon content of cast iron; Under the preferable case, the condition of said carbonization treatment can comprise: oxygen supply pressure is that 0.4-0.8MPa, oxygen flow can be 2000-4000Nm
3/ h, oxygen supply can be 2-6 minute the time.
A kind of preferred embodiment in; Preparing method provided by the invention also is included in before the oxygen supply, in the decarburization stove, adds the dephosphorization material, and the add-on of said dephosphorization material can in very large range change; Under the preferable case; Blast-melted with respect to 100 weight parts, the add-on of dephosphorization material can be the 2-5 weight part, most preferably is the 3-4 weight part.
In a kind of preferred embodiment, the condition of said carbonization treatment makes in the cast iron liquid that obtains, and the content of carbon is 2.7-3 weight %, and the content of sulphur is below the 0.08 weight %, and the content of phosphorus is below the 0.1 weight %; Most preferably, the condition of said carbonization treatment makes in the cast iron liquid that obtains, and the content of carbon is 2.7-3 weight %, and the content of sulphur is 0.02-0.06 weight %, and the content of phosphorus is 0.02-0.08 weight %.
Among the present invention, the kind of said dephosphorization material is conventionally known to one of skill in the art, for example, can be lime and/or fluorite.
In a kind of preferred implementation, said dephosphorization material is lime and fluorite, and the weight ratio of lime and fluorite can be 2-5: 1.
Said lime can be commercially available, and for example, CaO content is the lime of 85-95 weight %, and said fluorite can be commercially available, CaF in the fluorite
2Content can be for more than the 75 weight %.
According to the present invention, the cast iron liquid that obtains after the carbonization treatment is incorporated in the ladle, and in cast iron liquid, introduces the alloying raw material, and alloying; The condition of said alloying can in very large range change, and preferably, the condition of said alloying can comprise: the temperature of alloying is 1450-1550 ℃, and the time of alloying is 3-10 minute; More preferably, the temperature of alloying is 1480-1530 ℃, and the time of alloying is 4-6 minute.Said alloying raw material can be adjusted according to the composition of the cast iron that finally makes, and preferably, said alloying raw material is ferrosilicon and/or ferromanganese.
In a kind of preferred implementation, the add-on of ferrosilicon and/or ferromanganese and the condition of alloying make in the cast iron liquid after the alloying, and silicone content can be 0.8-2 weight %, and manganese content can be 0.5-1.5 weight %.More preferably, the add-on of said ferrosilicon and/or ferromanganese and the condition of alloying make in the cast iron liquid after the alloying, and silicone content is 1-1.5 weight %, and manganese content is 0.6-1 weight %.
In addition; In order further to reduce the oxygen level in the cast iron liquid, preferably before alloying, add silit cast iron liquid is handled, the add-on of said silit can in very large range change; Preferably; The add-on of said silit makes in the cast iron liquid after the deoxidation, and the content of oxygen is below the 50ppm, and the increase that makes carbon content is less than 0.01 weight %.
Among the present invention, said blast-melted composition can in very large range change, preferably; Said blast-melted in, carbon content can be 3.5-4.5 weight %, manganese content is 0.2-1.5 weight %; Sulphur content is 0.02-0.15 weight %, and phosphorus content is 0.05-0.4 weight %; More preferably, carbon content can be 3.5-4.5 weight %, and manganese content can be 0.2-1.2 weight %, and sulphur content can be 0.02-0.08 weight %, and phosphorus content can be 0.06-0.2 weight %.
In addition, after the alloying, the cast iron liquid after the alloying is incorporated in the cast iron mould, the cooling back demoulding obtains cast iron.
The present invention will be described in more detail through concrete embodiment below.
Embodiment 1
Use blast furnace to produce canned molten iron and make raw materials for production, wherein, 1200 ℃ of molten iron temperatures, carbon content is 4.5 weight %, and silicone content is 0.2 weight %, and manganese content is 1.5 weight %, and sulphur content is 0.08 weight %, and phosphorus content is 0.4 weight %, and surplus is an iron.
This molten iron (5 tons) is incorporated in the decarburization stove (5 tons of capacity), and in the decarburization stove, adds lime (calcium oxide content is 85 weight %) and fluorite (Calcium Fluoride (Fluorspan) content is 78 weight %), feeding quantity is 200 kilograms (weight ratio of lime and fluorite is 2: 1).Then, decarburization is carried out in oxygen supply in the decarburization stove, and oxygen supply pressure is 0.4MPa, and oxygen flow is 2000Nm
3/ h, oxygen supply time is 6min, obtains cast iron liquid.
After decarburization finishes, through the elemental composition of Chemical Analysis method detection cast iron liquid, wherein; The temperature of cast iron liquid is 1500 ℃, and carbon content is 2.7 weight %, and silicone content is 0.2 weight %; Sulphur content is 0.08 weight %, and phosphorus content is 0.1 weight %, and manganese content is 0.5 weight %.
The cast iron liquid that obtains is poured in the ladle (6 tons of capacity); And add 20 kilograms of silit (SiC content is 75 weight %); And add 170 kilograms of ferrosilicon (Si: the Fe mol ratio is 3.65: 1) and 30 kilograms of ferromanganese (Mn: the Fe mol ratio is 1.85: 1); With alloying, the temperature of alloying is 1500 ℃, and the time of alloying is 6 minutes.After the alloying, analyze through the cast iron liquid of Chemical Analysis method after to alloying, wherein, silicone content is 0.5 weight %, and manganese content is 0.8 weight %, and carbon content is 2.705 weight %.
Cast iron liquid after the alloying is poured in the cast iron mould, be cooled to room temperature after, obtain the cast iron of 50 kilograms/piece.
Embodiment 2
Adopt smelting furnace to produce canned molten iron and make raw materials for production, wherein, molten iron temperature is 1450 ℃, and carbon content is 3.5 weight %, and silicone content is 0.8 weight %, and manganese content is 0.8 weight %, and sulphur content is 0.06 weight %, and phosphorus content is 0.2 weight %, and surplus is an iron.
This molten iron (30 tons) is introduced in the decarburization stove (capacity is 30 tons), and in this decarburization stove, added lime (calcium oxide content is 88 weight %) and fluorite (Calcium Fluoride (Fluorspan) content is 80 weight %), feeding quantity is 900 kilograms (weight ratio of lime and fluorite is 5: 1).Then, decarburization is carried out in oxygen supply in the decarburization stove, and oxygen supply pressure is 0.7MPa, and oxygen flow is 3000Nm
3/ h, oxygen supply time is 3min, obtains cast iron liquid.
After decarburization finishes, through the elemental composition of Chemical Analysis method detection cast iron liquid, wherein; The temperature of cast iron liquid is 1550 ℃, and carbon content is 2.8 weight %, and silicone content is 0.8 weight %; Sulphur content is 0.06 weight %, and phosphorus content is 0.08 weight %, and manganese content is 0.5 weight %.
The cast iron liquid that obtains is poured in the ladle (31 tons of capacity); And add 70 kilograms of silit (content of SiC is 75 weight %); And add 660 kilograms of ferrosilicon (Si: the Fe mol ratio is 3.65: 1) and 20 kilograms of ferromanganese (Mn: the Fe mol ratio is 1.85: 1); With alloying, the temperature of alloying is 1550 ℃, and the time of alloying is 7 minutes.After the alloying, analyze through the cast iron liquid of Chemical Analysis method after to alloying, wherein, silicone content is 1.6 weight %, and manganese content is 0.75 weight %, and carbon content is 2.802 weight %.
Cast iron liquid after the alloying is poured in the cast iron mould, be cooled to room temperature after, obtain the cast iron of 50 kilograms/piece.
Embodiment 3
Adopt blast furnace to produce canned molten iron and make raw materials for production, wherein, molten iron temperature is 1300 ℃, and carbon content is 4.00 weight %, and silicone content is 0.6 weight %, and manganese content is 0.2 weight %, and sulphur content is 0.035 weight %, and phosphorus content is 0.3 weight %.
In the decarburization stove (capacity is 15 tons) that this molten iron (15 tons) is incorporated into, and in this decarburization stove, add lime (calcium oxide content is 91 weight %) and fluorite (Calcium Fluoride (Fluorspan) content is 80 weight %), feeding quantity is 600 kilograms (weight ratio of lime and fluorite is 3: 1).Then, decarburization is carried out in oxygen supply in the decarburization stove, and oxygen supply pressure is 0.6MPa, and oxygen flow is 3000Nm
3/ h, oxygen supply time is 2min, obtains cast iron liquid.
After decarburization finishes, through the elemental composition of Chemical Analysis method detection cast iron liquid, wherein; The temperature of cast iron liquid is 1550 ℃, and carbon content is 2.89 weight %, and silicone content is 0.6 weight %; Sulphur content is 0.035 weight %, and phosphorus content is 0.1 weight %, and manganese content is 0.1 weight %.
The cast iron liquid that obtains is poured in the ladle (16 tons of capacity); Add 20 kilograms of silit (SiC content is 75 weight %); And add 350 kilograms of ferrosilicon (Si: the Fe mol ratio is 3.65: 1) and 200 kilograms of ferromanganese (Mn: the Fe mol ratio is 1.85: 1) with alloying; The temperature of alloying is 1550 ℃, and the time of alloying is 5 minutes.After the alloying, analyze through the cast iron liquid of Chemical Analysis method after to alloying, wherein, silicone content is 1.6 weight %, and manganese content is 1.3 weight %, and carbon content is 2.9 weight %.
Cast iron liquid after the alloying is poured in the cast iron mould, be cooled to room temperature after, obtain the cast iron of 50 kilograms/piece.
Embodiment 4
Adopt blast furnace to produce canned molten iron and make raw materials for production, wherein, molten iron temperature is 1300 ℃, and carbon content is 4.00 weight %, and silicone content is 0.4 weight %, and manganese content is 0.8 weight %, and sulphur content is 0.035 weight %, and phosphorus content is 0.3 weight %.
In the decarburization stove (capacity is 15 tons) that this molten iron (15 tons) is incorporated into, and in this decarburization stove, add lime (calcium oxide content is 91 weight %) and fluorite (Calcium Fluoride (Fluorspan) content is 80 weight %), feeding quantity is 600 kilograms (weight ratio of lime and fluorite is 4: 1).Then, decarburization is carried out in oxygen supply in the decarburization stove, and oxygen supply pressure is 0.6MPa, and oxygen flow is 3000Nm
3/ h, oxygen supply time is 4min, obtains cast iron liquid.
After decarburization finishes, through the elemental composition of Chemical Analysis method detection cast iron liquid, wherein; The temperature of cast iron liquid is 1500 ℃, and carbon content is 3.0 weight %, and silicone content is 0.4 weight %; Sulphur content is 0.035 weight %, and phosphorus content is 0.1 weight %, and manganese content is 0.1 weight %.
The cast iron liquid that obtains is poured in the ladle (16 tons of capacity); Add 20 kilograms of silit (SiC content is 75 weight %); And add 350 kilograms of ferrosilicon (Si: the Fe mol ratio is 3.65: 1) and 300 kilograms of ferromanganese (Mn: the Fe mol ratio is 1.85: 1) with alloying; The temperature of alloying is 1500 ℃, and the time of alloying is 4 minutes.After the alloying, analyze through the cast iron liquid of Chemical Analysis method after to alloying, wherein, silicone content is 1.7 weight %, and manganese content is 0.8 weight %, and carbon content is 3.0 weight %.
Cast iron liquid after the alloying is poured in the cast iron mould, be cooled to room temperature after, obtain the cast iron of 50 kilograms/piece.
Can find out from the foregoing description; Method provided by the invention can be used in the cast iron of the multiple composition content of preparation, and the raw material sources of method provided by the invention are extensive, and stable components; Can satisfy the demand of raw material in the Cast Iron Production; And significantly reduce with respect to its energy consumption of electric arc furnace smelting method, reduced production cost widely, application prospect is extensive.
Claims (10)
1. the preparation method of a cast iron, wherein, this method comprises:
(1) is incorporated in the decarburization stove blast-melted, under oxygen supply condition, carries out carbonization treatment, obtain cast iron liquid;
(2) cast iron liquid is incorporated in the ladle, and in cast iron liquid, introduces the alloying raw material, and alloying;
(3) the cast iron liquid after the alloying is incorporated in the cast iron mould, the cooling back demoulding obtains cast iron,
Wherein, the condition of said carbonization treatment makes in the cast iron liquid that obtains, and the content of carbon is 2.5-3.5 weight %, and the content of sulphur is below the 0.08 weight %, and the content of phosphorus is below the 0.1 weight %.
2. preparation method according to claim 1, wherein, the condition of said carbonization treatment makes in the cast iron liquid that obtains, and the content of carbon is 2.7-3 weight %, and the content of sulphur is 0.02-0.06 weight %, and the content of phosphorus is 0.02-0.08 weight %.
3. preparation method according to claim 1 and 2, wherein, the condition of said carbonization treatment comprises: oxygen supply pressure is that 0.4-0.8MPa, oxygen flow are 2000-4000Nm
3/ h, oxygen supply time are 2-6 minute.
4. preparation method according to claim 1, wherein, this method also is included in before the oxygen supply, in the decarburization stove, adds the dephosphorization material, blast-melted with respect to 100 weight parts, the add-on of dephosphorization material is the 2-5 weight part.
5. preparation method according to claim 4, wherein, said dephosphorization material is lime and/or fluorite.
6. preparation method according to claim 5, wherein, said dephosphorization material is lime and fluorite, and the weight ratio of lime and fluorite is 2-5: 1.
7. preparation method according to claim 1, wherein, said alloying raw material is ferrosilicon and/or ferromanganese; And the condition of said alloying comprises: the temperature of alloying is 1450-1550 ℃; The time of alloying is 3-10 minute, and the condition of the add-on of ferrosilicon and/or ferromanganese and alloying, makes in the cast iron liquid after the alloying; Silicone content is 0.8-2 weight %, and manganese content is 0.5-1.5 weight %.
8. preparation method according to claim 7, wherein, the add-on of said ferrosilicon and/or ferromanganese and the condition of alloying make in the cast iron liquid after the alloying, and silicone content is 1-1.5 weight %, and manganese content is 0.6-1 weight %.
9. preparation method according to claim 1, this method also are included in before the alloying, in cast iron liquid, add silit and make the deoxidation of cast iron liquid, and the increase of carbon content is less than 0.01 weight % after the adding of silit.
10. preparation method according to claim 1, wherein, said blast-melted in; Carbon content is 3.5-4.5 weight %, and silicone content is 0.2-0.8 weight %, and manganese content is 0.2-1.5 weight %; Sulphur content is 0.02-0.1 weight %, and phosphorus content is 0.05-0.4 weight %.
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| CN2010105264366A CN102453832A (en) | 2010-10-25 | 2010-10-25 | Preparation method of cast iron |
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| CN2010105264366A CN102453832A (en) | 2010-10-25 | 2010-10-25 | Preparation method of cast iron |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102925787A (en) * | 2012-09-11 | 2013-02-13 | 青岛和德隆机械有限公司 | Raw material composition for valve castings special for medium and high pressure oil fields and production method for raw material composition |
| CN109439833A (en) * | 2018-12-11 | 2019-03-08 | 滨州亚泰雅德动力配件有限公司 | High Nickel Cast Iron Engine Stigma carbon content control method and device |
| CN113832315A (en) * | 2021-09-27 | 2021-12-24 | 唐山鑫业科技有限公司 | Decarburization process for white malleable cast iron |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN86101370A (en) * | 1986-03-07 | 1987-01-24 | 陈庆伟 | Direct cast iron-melting method using blowing oxygen for blast furnace |
-
2010
- 2010-10-25 CN CN2010105264366A patent/CN102453832A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN86101370A (en) * | 1986-03-07 | 1987-01-24 | 陈庆伟 | Direct cast iron-melting method using blowing oxygen for blast furnace |
Non-Patent Citations (1)
| Title |
|---|
| 王克非 等: "铸造生铁氧化脱磷的试验研究", 《华东冶金学院学报》, vol. 17, no. 3, 31 July 2000 (2000-07-31), pages 184 - 187 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102925787A (en) * | 2012-09-11 | 2013-02-13 | 青岛和德隆机械有限公司 | Raw material composition for valve castings special for medium and high pressure oil fields and production method for raw material composition |
| CN109439833A (en) * | 2018-12-11 | 2019-03-08 | 滨州亚泰雅德动力配件有限公司 | High Nickel Cast Iron Engine Stigma carbon content control method and device |
| CN113832315A (en) * | 2021-09-27 | 2021-12-24 | 唐山鑫业科技有限公司 | Decarburization process for white malleable cast iron |
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Application publication date: 20120516 |