CN106319155A - Method and device for adding high-steam-pressure magnesium into molten steel - Google Patents
Method and device for adding high-steam-pressure magnesium into molten steel Download PDFInfo
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- CN106319155A CN106319155A CN201510381344.6A CN201510381344A CN106319155A CN 106319155 A CN106319155 A CN 106319155A CN 201510381344 A CN201510381344 A CN 201510381344A CN 106319155 A CN106319155 A CN 106319155A
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Abstract
The invention provides a method and device for adding high-steam-pressure magnesium metal into molten steel. The magnesium adding device is mainly composed of a storage bucket, a control valve and a body; the body is composed of a conveying pipe, an embedded pipe and a three-way pipe. The method comprises the steps that the magnesium adding device is put into a tubular furnace, pure magnesium particles with the particle size ranging from 0.5 mm to 2 mm are contained into the storage bucket, after the temperature of the lower middle portion of the conveying pipe set rises to 1120 DEG C to 1200 DEG C, the control valve is opened, the pure magnesium particles are added into the conveying pipe set at the speed ranging from 0.5 g/min to 1.5 g/min, meanwhile, an argon adjusting valve is opened, argon is led in with the flow ranging from 0.5 L/min to 1.5 L/min, and magnesium steam in the conveying pipe is loaded into the molten steel. Accordingly, the method and device have the beneficial effects that magnesium is stably and safely added into the molten steel, the yield of the magnesium is high, alloy elements are not introduced, the production cost is low, and magnesium distribution in the molten steel is uniform.
Description
Technical field
The present invention relates to a kind of molten steel and add method and the device thereof of high vapour pressure magnesium, this device is put into tube furnace,
When temperature reaches design temperature, after making magnesium metal form magnesium vapor, reload in molten steel.
Background technology
Steel-making is a refinement oxide process, is i.e. blown into oxygen in ferrum liquid, by the pig iron excess element (C, Si,
Mn) and impurity (S, P) remove, reach to meet the limit of steel grade performance.Due to the effect of oxygen furnace steel, making steel latter stage,
In molten steel, oxygen content maximum can reach 0.1%, but the dissolubility that oxygen is in solid steel is extremely low (such as dissolves in δ-Fe
Degree is 0.0082% to the maximum), the oxygen of these excess will separate out with the form of FeO or other oxide during solidification,
Thus reduce the serviceability of steel.So, must be by the oxygen removal in molten steel after decarburization terminates.Oxygen bag in steel
Include the free oxygen [O] of dissolvingDWith the oxygen [O] in field trashL, deoxygenate i.e. by add in molten steel deoxidizer (such as manganese, silicon,
Titanium, aluminum, magnesium etc.), the free oxygen in steel is transferred to oxide and is situated between in thing (inclusion), float and remove, reach
Purpose to the oxygen content reduced in steel.And the level of oxygen content in steel can indirectly reflect steel intermediary in thing quantity level,
Total oxygen T [O] in Common Steels represents the cleanliness factor of molten steel.
Total oxygen demand T [O] in steel has close relationship, the requirement such as figure to oxygen content of typical case's steel grade with the quality of product
Shown in 1, therefore, how to reduce the oxygen content in steel, improve the cleanliness factor of steel, the most effectively utilize deoxidation products also
Increasingly paid close attention to by metallargist.
According to the difference of deoxidizing capacity, deoxygenated alloy is divided into weak deoxidizer (such as deoxidizers such as Mn, Si, Ti) and takes off by force
Oxygen agent (such as Al, Mg etc.).In early days iron and steel often use in producing silicon, manganese as deoxidizer, due to flat with Si, Mn
The oxygen content of weighing apparatus is higher, and for the oxygen content in steel is removed to extremely low level, major part iron and steel enterprise all uses Al conduct
End-deoxidizer.Having research display, when dissolving aluminum content in steel and being 0.03%-0.05%, in steel, averaged Oxygen content can drop
Low to below 3ppm.But, remain in tufted (cluster) Al in steel after aluminium deoxidation2O3It is mingled with and can be substantially reduced
The plasticity of steel, toughness, fatigue strength, resistance to corrosion, particularly destroy the seriality of steel matrix, at dead load
With cause material failure under the effect of dynamic load, reduce steel product rate and product quality.On the other hand, molten steel cast
During Al2O3It is mingled with and easily causes nozzle blocking to cause the production accidents such as cast interruption.
And magnesium elements has the strongest chemism, in molten steel, Mg has the strongest affinity to nonmetalloid.Early
At 1970 ' s, Mori etc. the most once pointed out the probability that molten steel is deoxygenated by magnesium vapor, and it utilizes magnesium as deoxidizer, obtains
Obtain [%Mg] [%O] < 1.0 × 10 when 1873K-6.Saxena etc. have studied the probability making steel-making refining agent with magnesium,
Research finds, forms minimum, spinelle (spinel) the type oxygen of Dispersed precipitate (uniform distribution) in steel
Compound, this spinelle is to the fatigue behaviour of steel and other performance undamaged evil.
(Tateyama etc. use magnesium core-spun yarn (cored wire) (Mg, MgO, CaF2) in mild steel argon shield
Magnesium deoxidation, desulfurization is carried out in induction furnace.) addition of magnesium less than 15%, can be by molten steel after 5 minutes
T [O] is reduced to 9ppm, and [S] is reduced to 3ppm；After static placement 10 minutes, the T [O] in molten steel, [S] do not find
Go up, be kept at the level of 11ppm and 3ppm.Therefore, it can be seen that Mg has with S and O in molten steel
Strong affinity, and do not change molten steel component, it is preferably to deoxygenate and desulfurizing agent.Additionally, oxide smelting in recent years
The development of technology for gold, utilizes Mg to process molten steel and obtains high-melting-point, being situated between at thing crystal grain thinning containing magnesium of tiny, disperse,
The relevant issues adding Mg in molten steel are made to become hot issue.
It is true that in steel manufacture process, used Gas injection method by passivated magnesium (passivation
Magnesium), in granule sprays into molten iron (hot metal), the purpose of desulfurizing iron is reached.It is also adopted by the method being similar to
Magnesium is passed through in ferrum liquid production spheroidal graphite cast-iron (nodular cast iron).Refer to shown in Fig. 2, the steam of Mg Yu Al
Pressure and the relation of temperature, as can be seen from Figure 2 at a temperature of steel-making, (1600 DEG C) Mg has the highest vapour pressure (its
Vapour pressure is 200 times of aluminum), it is obvious that owing to being far above molten iron temperature at molten steel temperature (1600 DEG C)
(1300-1400 DEG C), the method for this winding-up Inactivate granular magnesium cannot directly apply to the magnesium of molten steel and process processing procedure.Therefore exist
The most largely limit magnesium use in actual STEELMAKING PRODUCTION.Therefore the most safely and effectively mode will
Magnesium adds molten steel, becomes one of molten steel magnesium key problem processing metallurgical technology.
The method that magnesium adds molten steel the most generally used pours method, injection feeding technology (cored wire method), pressure
Entering method (plunging method) etc., the alloy species of addition has magnesium-rare earth, high magnesium alloy, Inactivate granular magnesium etc..
The disclosed patent of China describes a kind of side adding magnesium at ingot mould (ingot mold) bottom even place mat NiMg alloy
Method.In the NiMg alloy added, Mg content range is 5-50%.It will be apparent that this kind of method introduces in molten steel
W metal, had both destroyed the chemical composition of original molten steel, had too increased the cost of production.Meanwhile, this kind is being applied
During method, the oxygen position in steel need to be adjusted to a higher level, the total oxygen content of the molten steel also made rises.
Separately there is the magnesium core-spun yarn of a kind of special construction, by this magnesium heart yearn by wire-feeding device comprising straightening wire-leading device (cored wire injection
System) feeding molten steel depths.It will be apparent that magnesium heart yearn is when arriving bottom molten steel, magnesium general's generation Mg (s) → Mg (l) →
The evolution process of Mg (g), due to variations in temperature huge between molten steel and magnesium heart yearn so that the mistake of Mg (s) → Mg (g)
Journey i.e. completed within the ofest short duration time, owing to magnesium is in gasification, by producing the biggest pressure, easily made
Molten steel is become acutely to seethe and produce production accident.One is also had to utilize thermit reduction (Aluminothermic reduction)
The Mg steam of preparation, and utilize argon, as carrier, magnesium vapor is imported molten steel.
Although tradition is the most multiple, and magnesium adds the mode in molten steel, it is apparent that the most still there is flaw, and nonideal mode,
Inventor lacks for this, is studied improvement especially, and by specialty itself and experiment experience for many years, finally
After going through test repeatedly, revising and improve, and there is the birth of the present invention.
Summary of the invention
The present invention is related to a kind of method and device thereof adding high vapour pressure magnesium in molten steel, and this device is i.e. the interpolation of magnesium
Device, includes airtight storage vat, control valve and conveying pipe group.Tube furnace is put into by by magnesium adding set,
Again the pure magnesium grain that particle diameter is 0.5～2mm is loaded in storage vat.Because when pure magnesium grain particle diameter is less than 0.5mm, meeting
Magnesium grain is contacted through the embedded Guan Eryu molten steel in conveying pipe group, and when particle diameter is more than 2mm, then can make magnesium
Grain cannot enter conveying pipe through controlling valve.When pipe middle and lower part to be conveyed temperature rises to 1120 DEG C-1200 DEG C, will control
Valve is opened, and with suitable charging rate, pure magnesium grain is added conveying and manages, and opens argon regulation valve at this moment.Because working as
Argon flow amount is less than 0.2L/min, the Argon Bubble containing magnesium formed bottom molten steel can be made excessive, be unfavorable in Argon Bubble
The magnesia molten steel that passes to, and when argon flow amount is more than 0.5L/min, or make the vapour pressure of the magnesium on molten steel surface too low,
Magnesium recovery rate is caused to reduce.So being passed through argon with the flow of 0.2-0.5L/min, can inciting somebody to action of safety carry the most again
Magnesium vapor in pipe is loaded in molten steel.
And oxygen in magnesium metal and steel, sulfur have an extremely strong affinity, and there is the highest deoxidation and desulfurized effect,
And its MgO, MgS Jie generated has the features such as tiny, even particle size distribution at thing.Utilize magnesium as steelmaking process
First deoxidant element, or as secondary deoxidization desulfuration element, the total oxygen, the sulfur content that are possible not only to realize in steel reach pole
Low level, it is possible to as the modification agent (inclusion modifier) after using aluminum, titanium etc. as first deoxidation, by steel
Large-scale aluminium oxide and titanyl compound are situated between and modify as tiny magnalium, compound Jie of magnesium titanium at thing at thing.For oxide smelting
The application of technology for gold lays the foundation.
But the fusing point of magnesium metal and boiling point are respectively 670 DEG C and 1100 DEG C, in steel-making temperature (1600 DEG C) condition
Under, its vapour pressure is up to 20-25 atmospheric pressure, as solid metallic magnesium being directly added into molten steel, and on the one hand can not
The molten steel that causes avoided acutely seethes, even explosion accident, on the other hand also makes the recovery rate degradation of magnesium.Institute
To use the device and method of the present invention, magnesium can be added in molten steel with safety and efficient mode, become at molten steel magnesium
The key point of reason.
Accompanying drawing explanation
Fig. 1 is existing typical case's steel grade requirement figure to oxygen content；
Fig. 2 is the vapour pressure graph of a relation with temperature of existing Mg Yu Al；
Fig. 3 is the generalized section of magnesium adding set of the present invention；
Fig. 4 is the schematic diagram that magnesium adding set of the present invention puts into tube furnace.
Description of reference numerals: 1 magnesium adding set；11 storage vats；12 control valves；13 bodies；131
Conveying pipe；132 embedded pipes；1321 pores；133 tee Ts；14 temperature inductors；15
Resistance to scouring coating；16 crucibles；2 tube furnaces；20 burner hearths；21 pipelines；211 valves；212 valves
Door；213 valves；22 gas purifiers；23 effusion meters；230 effusion meters；24 delivery conduit；3
Molten steel；4 temperature-sensitive stickers.
Detailed description of the invention
The following is embodiment, but present disclosure is not limited to the scope of these embodiments.
First, referring to shown in Fig. 3, for the generalized section of magnesium adding set of the present invention, this magnesium adding set 1 is main
If being made up of storage vat 11, control valve 12 and body 13.This body 13 has a conveying pipe 131,
Being provided with embedded pipe 132 inside hollow, this body 13 is a conveying pipe 131, and sidewall is provided with a tee T 13
3, it is available for argon and injects, and in carrying pipe 131, be provided with an embedded pipe 132, be positioned at bottom embedded pipe 132
For closing and offering several pore 1321, and bottom embedded pipe 132, it is provided with a temperature inductor 14,
Be positioned at body 13 inwall and be then formed with a resistance to scouring coating (corrosion resistant coating) 15, above-mentioned respectively
Element is all compact siro spinning technology, prevents air from entering.
Secondly, the magnesium adding set 1 of the present invention is installed in the burner hearth 20 of tube furnace 2, coordinates refering to Fig. 4 institute
Show, magnesium adding set 1 is put into tube furnace 2, the upper and lower side of the magnesium adding set 1 in this tube furnace 2 mat respectively
Extended connection by pipeline 21, and be provided with valve 211,212 and 213 respectively at diverse location, be positioned at valve
It is provided with a gas purifier 22 between door 211 and 213, and is provided with effusion meter 23 and 230, topmost
Then it is connected to valve 213 by a delivery conduit 24, is positioned at magnesium adding set 1 inwall and has inserted crucible for inserting steel
Liquid 3, is then provided with a temperature-sensitive sticker 4 as at tube furnace 2 outer wall.
And under conditions of steel-making temperature 1600 DEG C, how can safely and can high recovery rate magnesium is added molten steel, just
It it is the important core of the present invention.Please referring still to shown in Fig. 3 and 4, when the present invention is actually used, first by valve 2
11,212 and 213 opening, then control valve 212 makes effusion meter 230 range of flow be 1-2
The flow of L/min, and it is passed through argon 10 minutes so that the partial pressure of oxygen in tube furnace 2 is down to minimum.Then by particle diameter
Be 0.5～2min pure magnesium grain load in storage vat 11, and control valve 213 makes effusion meter 23 range of flow be
After the flow of 0.5～1L/min is passed through argon 5 minutes, close valve 213.It is then electrified to tube furnace 2 crucible 1
After steel in 6 is warming up to 1600 DEG C, holding temperature and make the steel in crucible 16 dissolve completely, the temperature more making molten steel 3 is equal
Homogenize.
Now, magnesium adding set 1 is put above tube furnace 2 crucible 16, treat that temperature inductor 14 detects temperature
When scope is in the range of 1120 DEG C-1200 DEG C, and constant within the range.Now open control valve 12, with necessarily
Add magnesium grain speed, the pure magnesium grain in storage vat 11 is joined in embedded pipe 132, and can be by temperature by pure
The gasification of magnesium grain forms magnesium vapor.Now open valve 213, with 0.2～0.5L/min flow, be passed through argon, complete
The process of magnesium is added in molten steel.
Therefore, the present invention is used to add the technology of high vapour pressure magnesium in molten steel 3, it is clear that to have the advantage that
(1) present invention mainly adds pure magnesium in molten steel 3, so it is multiple by molten steel 3 composition to introduce other element
Hydridization.
(2) the invention is characterized in that by recycling argon after the gasification of magnesium metal steam be that carrier is added to molten steel 3
In, it is to avoid the danger of blast is there is with liquid molten steel because solid-state magnesium granules directly contacts.
(3) present invention is in implementation process, omnidistance uses argon as protective gas, it is to avoid magnesium and air contact and
Oxidation.
(4) present invention's it is important that utilize the temperature range of interior 1120 DEG C-1200 DEG C of the burner hearth 20 of tube furnace 2 to reach
The gasification of magnesium, it is not necessary to additionally install the heater of the gasification magnesium that heats up additional.
(5) present invention be within the temperature range of 1120 DEG C-1200 DEG C by solid-state magnesium gasify, in this temperature range its
The vapour pressure of magnesium is only 4 atmospheric pressure.
(6) present invention is in the part of embedded pipe 132, and this embedded pipe 132 is high temperature resistant stainless steel material；Therefore
In magnesium gasification, do not result in conveying pipe 131 burst.
(7) present invention is when adding magnesium to molten steel 3, is using argon as carrier, can the one-tenth of very well and uniform molten steel 3
Point, it is to avoid during tube furnace 2 adds, magnesium component is in the uneven situation of molten steel 3 total distributed.
(8) present invention is when adding magnesium to molten steel 3, and the response rate of magnesium is higher.
(9) present invention can add the amount of magnesium of embedded pipe 14 by controlling storage vat 11, and coordinate and add the magnesium time and reach
To accurately controlling content of magnesium in steel.
In sum, the present invention can add in molten steel safely, stably by magnesium, and does not introduce other alloy unit
Element, not only production cost is low and the recovery rate of magnesium is high, especially the distributing very evenly, again before application also of the magnesium in molten steel
Finding no same or similar device or method is applied for a patent formerly or disclosed data, reason has met patent of invention
Important document, whence proposes patent application in accordance with the law.
Embodiment described above is only to be described the preferred embodiment of the present invention, the not model to the present invention
Enclose and be defined, on the premise of designing spirit without departing from the present invention, those of ordinary skill in the art's skill to the present invention
Various deformation that art scheme is made and improvement, all should fall in the protection domain that claims of the present invention determines.
Claims (6)
1. the method that a molten steel adds high vapour pressure magnesium, it is characterised in that mainly set a magnesium adding set and put into pipe
In formula stove, when magnesium add device middle and lower part temperature rise to design temperature time, add pure magnesium grain, make pure magnesium particle shape become magnesium vapor,
By argon, magnesium vapor is loaded in molten steel.
2. the method that molten steel as claimed in claim 1 adds high vapour pressure magnesium, it is characterised in that argon regulation valve with
The flow of 0.5～1.5L/min is passed through argon.
3. the method that molten steel as claimed in claim 1 adds high vapour pressure magnesium, wherein, this magnesium vapor utilize argon with
The flow of 0.2～0.5L/min is added in molten steel.
4. the method that molten steel as claimed in claim 1 adds high vapour pressure magnesium, wherein, the particle diameter of this pure magnesium grain is
0.5～2mm.
5. the device of the molten steel high vapour pressure magnesium of interpolation, it is characterised in that it is mainly by magnesium adding set and tube furnace institute
Composition, this magnesium adding set includes:
One storage vat, for hermetic container, is located at topmost；
One body, for hollow tubular, combines closely with this storage vat, forms a conveying pipe；One control valve, is located at
Between this storage vat and this conveying pipe, the blanking of storage vat can be adjusted；One embedded pipe, is located in this conveying pipe, and it is close
Closing shape, bottom offers several pore.
6. molten steel as claimed in claim 5 adds the device of high vapour pressure magnesium, wherein, offers bottom this embedded pipe
Several apertures are less than the pore of pure magnesium grain.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510381344.6A CN106319155B (en) | 2015-07-02 | 2015-07-02 | Molten steel adds the method and its device of high vapour pressure magnesium |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510381344.6A CN106319155B (en) | 2015-07-02 | 2015-07-02 | Molten steel adds the method and its device of high vapour pressure magnesium |
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| CN106319155A true CN106319155A (en) | 2017-01-11 |
| CN106319155B CN106319155B (en) | 2018-07-06 |
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| CN201510381344.6A Expired - Fee Related CN106319155B (en) | 2015-07-02 | 2015-07-02 | Molten steel adds the method and its device of high vapour pressure magnesium |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112391574A (en) * | 2020-11-13 | 2021-02-23 | 新兴铸管股份有限公司 | Magnesium evaporator |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201010670Y (en) * | 2007-02-12 | 2008-01-23 | 四川龙蟒集团有限责任公司 | Magnesium granule blowing and desulphurizing device for molten iron |
| CN101298631A (en) * | 2008-06-16 | 2008-11-05 | 东北大学 | In situ mechanically rabbled furnace external desulfurization method and apparatus |
| KR20130075519A (en) * | 2011-12-27 | 2013-07-05 | 재단법인 포항산업과학연구원 | Desulfurizer using magnesium thermal reduction and desulfurizing method of molten iron using the same |
| CN104120213A (en) * | 2014-07-21 | 2014-10-29 | 东北大学 | Method and device for external desulfurization and refining of molten iron through injecting magnesium steam |
-
2015
- 2015-07-02 CN CN201510381344.6A patent/CN106319155B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201010670Y (en) * | 2007-02-12 | 2008-01-23 | 四川龙蟒集团有限责任公司 | Magnesium granule blowing and desulphurizing device for molten iron |
| CN101298631A (en) * | 2008-06-16 | 2008-11-05 | 东北大学 | In situ mechanically rabbled furnace external desulfurization method and apparatus |
| KR20130075519A (en) * | 2011-12-27 | 2013-07-05 | 재단법인 포항산업과학연구원 | Desulfurizer using magnesium thermal reduction and desulfurizing method of molten iron using the same |
| CN104120213A (en) * | 2014-07-21 | 2014-10-29 | 东北大学 | Method and device for external desulfurization and refining of molten iron through injecting magnesium steam |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112391574A (en) * | 2020-11-13 | 2021-02-23 | 新兴铸管股份有限公司 | Magnesium evaporator |
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