CN103882182B - A kind of high temperature steel cleaning molten method - Google Patents
A kind of high temperature steel cleaning molten method Download PDFInfo
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- CN103882182B CN103882182B CN201410109652.9A CN201410109652A CN103882182B CN 103882182 B CN103882182 B CN 103882182B CN 201410109652 A CN201410109652 A CN 201410109652A CN 103882182 B CN103882182 B CN 103882182B
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Abstract
The invention discloses a kind of high temperature steel cleaning molten method, the method adopts induction furnace melting high temperature steel, adopts bulk deoxidation, diffusive deoxidation and cast ladle in stove to add rare earth and in conjunction with ladle bottom porous plug blowing argon gas, realize high temperature steel cleaning molten.The present invention adopts in bulk deoxidation, diffusive deoxidation and ladle and adds rare earth and Argon mode melting high temperature steel, and high temperature steel oxygen level and inclusion content significantly reduce, and can significantly improve high temperature steel performance,
Description
Technical field
The invention belongs to cleaning molten technical field, relate to a kind of cleaning molten method in a series of heat-resisting consumable accessory preparation process such as bocca, grate plate, grid section, cracking tube on the industrial equipmentss such as electric power, building materials, metallurgy, petrochemical industry cracking.
Background technology
In alloy material high temperature steel smelting solidification process, there is nitrogen, hydrogen, oxygen and inclusion, especially the nickeliferous height of high temperature steel, this phenomenon is more serious.Deposit nitrogen in the melt, hydrogen, oxygen to reduce along with melt temperature, in cooling subsequently and process of setting, solubleness reduces, and the state that reaches capacity exists in gaseous form; Inclusion source point inclusion and outer inclusion.Outer inclusion can reduce as far as possible by controlling raw material quality, melt ladle, flow path groove refractory quality used and using method; Inclusion is as FeO, Fe
2o
3, MnO, SiO
2deng, and their mixture, this is first deoxidation products chemical reaction occurring and is formed of oxygen and deoxidation, and major part floats and enters slag, still has small portion to have little time floating and discharges and remain in steel.Therefore the purifying work of high temperature steel is mainly removed around deoxidation and eliminating and consequent deoxidation products.
Carry out a large amount of research work about the purifying invention of steel fusant both at home and abroad, especially achieve good result at large iron and steel enterprise (as Baogang, Wuhan Iron and Steel Plant, Baosteel etc.).At present, in the purifying normal employing stove of domestic and international iron and steel enterprise melt, melt is purifying in conjunction with external refining method, and external refining method has vacuum oven purifying method, AOD furnace method, BOD oven process, KF oven process, RH oven process etc.The use of these methods is for Be very effective such as deoxidation, degassed, removal of inclusions, but cost is high, complex procedures, investment are large.Electromagnetism is purifying is the removal of impurities novel method being subject to common concern in recent years at home and abroad, also obtains successful Application in aluminium processing industry.Electromagnetic purification is based on electromagnetic separation principle, major influence factors is magnetic field and electric current, the electromagnetic force that the material different according to electric conductivity is subject in magnetic field varies in size, utilize the difference of the specific conductivity of metal melt and nonmetal melt (inclusion), realize being separated of pure metal and non-metallic inclusion, electromagnetic purification method is also applied in Manufacture Of Iron And Steel By Melting carrying out by iron and steel scientific worker, but due to high temperature steel melt temperature high (1550 ~ 1650 DEG C), higher than molten aluminium (650-800 DEG C), also face many as filter temperature tolerance level, magnetic field accurately controls, the problems such as melt temperature strictly controls, be difficult at present solve, and cost is also higher.
Chinese invention patent application specification sheets CN102031384A discloses " a kind of method purified magnesium alloy fused mass ", this patent of invention adopts solid Slag inclusion in sheet or block foam ceramic foam filter magnesium alloy fused mass, realize purification magnesium alloy, but the oxygen be dissolved in melt, argon, nitrogen etc. can not be removed.
Summary of the invention
The object of the invention is to the shortcoming overcoming above-mentioned prior art, provide a kind of high temperature steel cleaning molten method, it is that realize high temperature steel high effect cleaning, production technique is simple by combining in conjunction with Argon to rare earth in slag deoxidation and ladle.
The object of the invention is to be achieved through the following technical solutions:
This high temperature steel cleaning molten method, adopts induction furnace melting high temperature steel, adopts bulk deoxidation, diffusive deoxidation and cast ladle in stove to add rare earth and in conjunction with ladle bottom porous plug blowing argon gas, realize high temperature steel cleaning molten.
Further, above at least three slag making, add Mn-Fe, Si-Fe pre-deoxidation of 1%, first add Mn-Fe by steel quality mark; Add the Al final deoxygenation of steel quality mark 0.15%, go out liquid steel temperature 1620 DEG C-1650 DEG C maintenance 5min-10min.
Further, above-mentioned diffusive deoxidation is pointed out by slag, is added in equably on slag blanket by reductor, and reductor comprises Si-Fe powder, Si-Ca powder, reductor granularity 1mm-3mm.
Further, above-mentioned Si-Fe powder add-on is 0.3% of steel quality mark; The add-on of described Si-Ca powder is 0.2% of steel quality mark.
Further, when ladle deoxidation, cast ladle baking, temperature is greater than 800 DEG C, and add the Yttrium base rare earth of 0.2%-0.3% before molten steel injects by steel quality mark, granularity 1mm-3mm, inject molten steel, slag mixes out; Ladle bottom porous plug adopts ceramic material, and Argon amount is that molten steel per ton blows 150 liters-250 liters, and Argon pressure is 1.0kg/ ㎡-2.0kg/ ㎡, and argon blowing time is 5min-10min.
Further, three slags are made during high temperature steel melting, furnace bottom adds 1% lime by steel quality mark, add alloy material, power transmission, see that molten steel adds slag making materials, after furnace charge melts and finishes, skim, slag making again, Mn-Fe and Si-Fe of 0.2% is added respectively by steel quality mark, first add Mn-Fe and add Si-Fe again, get stokehold sample analysis, add foundry returns, according to stokehold sample analytical results, add alloy adjusting component, 0.5% ferromanganese is added by steel quality mark, to be melted evenly after, 0.5% ferrosilicon is added again by steel quality mark, after fusing evenly, get sample after stove, skim, make new slag, after after stove, sample analytical results reaches component requirements, slag is pointed out simultaneously, 0.2% silicon-calcium powder is added in slag, insulation 5min-10min, the Al final deoxygenation of 0.15% is added according to steel quality mark.
Above-mentioned silicon-calcium powder granularity is 1min-3mm.
The present invention has following beneficial effect:
The present invention adopts in bulk deoxidation, diffusive deoxidation and ladle and adds rare earth and Argon mode melting high temperature steel, and high temperature steel oxygen level and inclusion content significantly reduce, and can significantly improve high temperature steel performance,
value improves 18.5%-30%, and work-ing life improves 20%.
Embodiment
High temperature steel cleaning molten method formula of the present invention adopts low cost induction furnace melting high temperature steel for medium-sized and small enterprises, adopts bulk deoxidation, diffusive deoxidation and cast ladle in stove to add rare earth and in conjunction with ladle bottom porous plug blowing argon gas, realize high temperature steel cleaning molten.The method at least three slag making, add Mn-Fe, Si-Fe pre-deoxidation of 1%, first add Mn-Fe by steel quality mark.Add the Al final deoxygenation of steel quality mark 0.15%, go out liquid steel temperature 1620 DEG C-1650 DEG C maintenance 5min-10min.Be added in equably on slag blanket by reductor, reductor comprises Si-Fe powder (adding by steel quality mark 0.3%), Si-Ca powder (adding by steel quality mark 0.2%), reductor granularity 1mm-3mm.
When ladle deoxidation, cast ladle baking, temperature is greater than 800 DEG C, and add the Yttrium base rare earth of 0.2%-0.3% before molten steel injects by steel quality mark, granularity 1mm-3mm, inject molten steel, slag mixes out; Ladle bottom porous plug adopts ceramic material, and Argon amount is that molten steel per ton blows 150 liters-250 liters, and Argon pressure is 1.0kg/ ㎡-2.0kg/ ㎡, and argon blowing time is 5min-10min.
Three slags are made during high temperature steel melting, furnace bottom adds 1% lime by steel quality mark, add alloy material, power transmission, see that molten steel adds slag making materials, after furnace charge melts and finishes, skim, slag making again, Mn-Fe and Si-Fe of 0.2% is added respectively by steel quality mark, first add Mn-Fe and add Si-Fe again, get stokehold sample analysis, add foundry returns, according to stokehold sample analytical results, add alloy adjusting component, 0.5% ferromanganese is added by steel quality mark, to be melted evenly after, 0.5% ferrosilicon is added again by steel quality mark, fusing evenly latter 5 minutes, get sample after stove, skim, make new slag, after after stove, sample analytical results reaches component requirements, slag is pointed out simultaneously, 0.2% silicon-calcium powder (granularity 1min-3mm) is added in slag, insulation 5min-10min, the Al final deoxygenation of 0.15% is added according to steel quality mark.
By ladle baking, in bag, temperature is not less than 800 DEG C, and put Yttrium base rare earth in bag, add, granularity 1min-3mm by the 0.2%-0.3% of Metal Weight, in stove, molten steel is poured in ladle, and slag mixes out, molten steel tapping temperature 1620 DEG C-1650 DEG C.
Open argon gas inflator, Argon amount blows 150 liters-250 liters by ladle molten steel amount molten steel per ton, and Argon pressure is 1.0kg/ ㎡-2.0kg/ ㎡, and argon blowing time is 5min-10min.
Below in conjunction with specific embodiment, the present invention is described in detail:
Embodiment 1
With 500kg medium-frequency induction furnace melting high temperature steel, smelting furnace is cleaned out, and furnace bottom adds 5kg lime, add the starting material such as low-carbon (LC) carbon steel scrap, waste stainless steel, low carbon ferrochromium, nickel plate, power transmission, is shown in that molten steel is with slag former, and furnace charge is skimmed after melting and finishing, add slag making materials, make new slag, add 1kg ferromanganese, add 1kg ferrosilicon subsequently, get stokehold sample analysis, add foundry returns.According to stokehold sample analytical results adjustment alloying constituent, add 2.5kg ferromanganese, add 2.5kg ferrosilicon subsequently, after fusing evenly, after 5min, get sample after stove, skim, make new slag, add 1kg aluminium, insert in stove to the furnace depth half degree of depth, slag point is pushed aside simultaneously, add 0.5kg silicon-calcium powder, granularity 1mm-3mm, keep 8min.By ladle baking, with infrared thermometer thermometric 850 DEG C, 1kg Yttrium base rare earth is placed at the bag end, granularity 1mm-3mm, and in stove, molten steel is poured in ladle, and slag mixes out, opens argon-blowing device, Argon amount 90 liters, Argon 8min, pressure 1.5kg/ ㎡.After argon gas has blown, close argon-blowing device, pour into a mould after leaving standstill 3min.Heat-resisting oxygen content in steel 20ppm after tested, inclusion content only 0.02%, and does not carry out σ compared with purifying treatment
1000 1000bring up to 13MPa by 10MPa, improve 30%.Do Ethylene Cracking Tube with HP40 and after purifying treatment, improve 20% work-ing life.
Embodiment 2
With 1000kg medium-frequency induction furnace melting high temperature steel ZG
40cr
25ni
20, smelting furnace is cleaned out, and furnace bottom adds 10kg lime, add the starting material such as low-carbon (LC) carbon steel scrap, waste stainless steel, low carbon ferrochromium, nickel plate, power transmission, is shown in that molten steel is with slag former, and furnace charge is skimmed after melting and finishing, add slag making materials, make new slag, add 2kg ferromanganese, add 2kg ferrosilicon subsequently, get stokehold sample analysis, add foundry returns.According to stokehold sample analytical results adjustment alloying constituent, add 5kg ferromanganese, add 5kg ferrosilicon subsequently, after melting even 5min, get sample after stove, skim, make new slag, add 2kg aluminium, insert in stove to the furnace depth half degree of depth, slag point is pushed aside simultaneously, add 0.5kg silicon-calcium powder, granularity 1mm-3mm, keep 8min.By ladle baking, with infrared thermometer thermometric 850 DEG C, 1kg Yttrium base rare earth is placed at the bag end, granularity 1mm-3mm, and in stove, molten steel is poured in ladle, and slag mixes out, opens argon-blowing device, Argon amount 90 liters, Argon 8min, pressure 1.5kg/ ㎡.After argon gas has blown, close argon-blowing device, pour into a mould after leaving standstill 3min.ZG after tested
40cr
25ni
20heat-resisting oxygen content in steel 18ppm, inclusion content only 0.02%, and does not carry out σ compared with purifying treatment
1000 1000bring up to 12.5MPa by 10.5MPa, improve 19%.Use ZG
40cr
25ni
20high temperature steel is prepared cement grate-cooler grate plate and is improve 20% work-ing life after purifying treatment.
Embodiment 3
With 1500kg medium-frequency induction furnace melting high temperature steel ZG
40cr
25ni
20, smelting furnace is cleaned out, and furnace bottom adds 15kg lime, add the starting material such as low-carbon (LC) carbon steel scrap, waste stainless steel, low carbon ferrochromium, nickel plate, power transmission, is shown in that molten steel is with slag former, and furnace charge is skimmed after melting and finishing, add slag making materials, make new slag, add 3kg ferromanganese, add 3kg ferrosilicon subsequently, get stokehold sample analysis, add foundry returns.According to stokehold sample analytical results adjustment alloying constituent, add 7.5kg ferromanganese, add 7.5kg ferrosilicon subsequently, after fusing evenly, after 5min, get sample after stove, skim, make new slag, add 3kg aluminium, insert in stove to the furnace depth half degree of depth, slag point is pushed aside simultaneously, add 1.5kg silicon-calcium powder, granularity 1mm-3mm, keep 8min.By ladle baking, with infrared thermometer thermometric 850 DEG C, 3kg Yttrium base rare earth is placed at the bag end, granularity 1mm-3mm, and in stove, molten steel is poured in ladle, and slag mixes out, opens argon-blowing device, Argon amount 270 liters, Argon 8min, pressure 1.5kg/ ㎡.After argon gas has blown, close argon-blowing device, pour into a mould after leaving standstill 3min.ZG after tested
40cr
25ni
20heat-resisting oxygen content in steel 15ppm, inclusion content only 0.018%, and does not carry out σ compared with purifying treatment
1000 1000bring up to 16MPa by 13.5MPa, improve 18.5%.Use ZG
40cr
25ni
20high temperature steel makes thermal power plant's bocca, and after purifying treatment, work-ing life improves 20%.
The method that in stove of the present invention, deoxidation degasification adopts bulk deoxidation and diffusive deoxidation to combine realizes the efficient deoxidation of stove.The deoxidation products that bulk deoxidation produces floats up in slag, oxygen in molten steel shifts to slag, along with the carrying out of bulk deoxidation, slag amount increases, molten metal and slag interface oxygen concn increase, establish the balance of oxygen in molten steel and slag, can affect the absorption of follow-up deoxidation products, bulk deoxidation efficiency is low.In slag, add diffusion deoxidizer, slough the oxygen in slag, destroy the balance with oxygen in slag in molten steel, the oxygen in molten steel is shifted gradually in slag, sets up new balance, thus be conducive to deoxidation, improve deoxidation effectiveness.Deoxidation is completed in stove, pour into the process of ladle at molten steel in stove, owing to contacting with the oxygen in air, secondary oxidation can be produced, therefore adopt in ladle and add the further deoxidation of rare earth, adopt blowing argon gas simultaneously, rapidly inclusion content in melting steel in ladle is taken in slag, thus obtain high metallurgical quality.
Claims (3)
1. a high temperature steel cleaning molten method, it is characterized in that, adopt induction furnace melting high temperature steel, to adopt in stove bulk deoxidation, diffusive deoxidation and cast ladle adds rare earth and in conjunction with ladle bottom porous plug blowing argon gas, realize high temperature steel cleaning molten, at least three slag making when bulk deoxidation, add Mn-Fe, Si-Fe pre-deoxidation of 1%, first add Mn-Fe by steel quality mark; Add the Al final deoxygenation of steel quality mark 0.15%, go out liquid steel temperature 1620 DEG C-1650 DEG C maintenance 5min-10min; Described diffusive deoxidation is pointed out by slag, is added in equably on slag blanket by reductor, and reductor comprises Si-Fe powder and/or Si-Ca powder, reductor granularity 1mm-3mm; When ladle deoxidation, cast ladle baking, temperature is greater than 800 DEG C, and add the Yttrium base rare earth of 0.2%-0.3% before molten steel injects by steel quality mark, granularity 1mm-3mm, inject molten steel, slag mixes out; Ladle bottom porous plug adopts ceramic material, and Argon amount is that molten steel per ton blows 150 liters-250 liters, and Argon pressure is 1.0kg/ ㎡-2.0kg/ ㎡, and argon blowing time is 5min-10min; Described Si-Fe powder add-on is 0.3% of steel quality mark; The add-on of described Si-Ca powder is 0.2% of steel quality mark.
2. high temperature steel cleaning molten method according to claim 1, it is characterized in that, three slags are made during high temperature steel melting, furnace bottom adds 1% lime by steel quality mark, add alloy material, power transmission, see that molten steel adds slag making materials, after furnace charge melts and finishes, skim, slag making again, Mn-Fe and Si-Fe of 0.2% is added respectively by steel quality mark, first add Mn-Fe and add Si-Fe again, get stokehold sample analysis, add foundry returns, according to stokehold sample analytical results, add alloy adjusting component, 0.5% ferromanganese is added by steel quality mark, to be melted evenly after, 0.5% ferrosilicon is added again by steel quality mark, after fusing evenly, get sample after stove, skim, make new slag, after after stove, sample analytical results reaches component requirements, slag is pointed out simultaneously, 0.2% silicon-calcium powder is added in slag, insulation 5min-10min, the Al final deoxygenation of 0.15% is added according to steel quality mark.
3. high temperature steel cleaning molten method according to claim 2, is characterized in that, described silicon-calcium powder granularity is 1mm-3mm.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104694704B (en) * | 2015-04-01 | 2016-11-23 | 山东瑞泰新材料科技有限公司 | The vacuum metling technique of nitrogen austenite heat resisting steel |
| CN108486313B (en) * | 2018-03-27 | 2019-11-19 | 南阳飞龙汽车零部件有限公司 | A kind of smelting technology promoting heat resisting steel intergranular degree of purity |
| CN111996330A (en) * | 2020-07-10 | 2020-11-27 | 海盐中达金属电子材料有限公司 | Process for smelting precise or special alloy by multi-slag method in medium-frequency induction furnace for desulfurization and oxygen removal |
| CN114934152B (en) * | 2022-06-14 | 2024-01-05 | 山西太钢不锈钢股份有限公司 | Continuous casting method of stainless steel with high rare earth content |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4093452A (en) * | 1975-07-23 | 1978-06-06 | British Steel Corporation | Refining liquid metal |
| CN1924028A (en) * | 2006-09-01 | 2007-03-07 | 西安交通大学 | Purifying and alloying method of wear-resistant steel fusant |
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2014
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4093452A (en) * | 1975-07-23 | 1978-06-06 | British Steel Corporation | Refining liquid metal |
| CN1924028A (en) * | 2006-09-01 | 2007-03-07 | 西安交通大学 | Purifying and alloying method of wear-resistant steel fusant |
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