CN105772666A - Center segregation control method for 30 CrMo circular tube blank and steel casting blank - Google Patents
Center segregation control method for 30 CrMo circular tube blank and steel casting blank Download PDFInfo
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- CN105772666A CN105772666A CN201610172935.7A CN201610172935A CN105772666A CN 105772666 A CN105772666 A CN 105772666A CN 201610172935 A CN201610172935 A CN 201610172935A CN 105772666 A CN105772666 A CN 105772666A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/10—Supplying or treating molten metal
- B22D11/11—Treating the molten metal
- B22D11/114—Treating the molten metal by using agitating or vibrating means
- B22D11/115—Treating the molten metal by using agitating or vibrating means by using magnetic fields
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/16—Controlling or regulating processes or operations
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/28—Manufacture of steel in the converter
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/072—Treatment with gases
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/10—Handling in a vacuum
Abstract
The invention relates to the field of ferrous metallurgy, in particular to a center segregation control method for a 30 CrMo circular tube blank and a 30 CrMo steel casting blank. The center segregation control method for the 30 CrMo circular tube blank and the 30 CrMo steel casting blank can improve center segregation parameter control and includes the following steps that a, a converter smelting process is implemented; b, an LF molten steel refining process is implemented; c, an RH refining process is implemented; and d, a molten steel continuous casting process is implemented, wherein the stirring current of a crystallizer electromagnetic stirrer ranges from 350 A to 400 A, the frequency ranges from 2 Hz to 4 Hz, parameters of a solidification final stage electromagnetic stirrer are characterized in that the stirring current ranges from 200 A to 300 A, the frequency ranges from 6.0 Hz to 8.0 Hz, the superheat degree control scope ranges from 15 DEG C to 35 DEG C, the pulling rate is controlled to range from 0.75 m/min to 1.00 m/min, and the secondary cooling specific water amount is controlled to range from 0.21 to 0.29 per kilometer of steel. Growth of columnar crystals is restrained, and control of center segregation parameters is improved. The center segregation control method is particularly suitable for producing the 30 CrMo circular tube blank and the 30 CrMo steel casting blank with the cross section phi being 350 mm.
Description
Technical field
The present invention relates to field of steel metallurgy, the center segregation control method of especially a kind of 30CrMo circular pipe blank steel strand.
Background technology
The steel for oil well pipes that 30CrMo tube blank steel uses mainly for the production of oil-gas mining, transport, chemical constituent is by weight percentage: C:0.27%～0.32%, Si:0.20%～0.35%, Mn:0.45%～0.65%, P≤0.020%, S≤0.010%, V≤0.015%, Cr::0.85%～1.05%, Mo:0.17%～0.24%, Cu≤0.15%, Ni≤0.20%, Alt:0.020%～0.040%, residual elements require: Nb≤0.010%, Ti≤0.010%, B≤0.005%, and V+Nb+Ti+B+Zr≤0.15%；As≤0.015%, Sn≤0.010%Sb≤0.010%, Pb≤0.008%, Bi≤0.010%, and As+Sn+Sb+Pb+Bi≤0.045%, surplus is Fe.In use under the combined effect of applied stress and hydrogen sulfide gas, often there is suddenly brittle failure (being called H 2 S stress corrosion) when stress is far below itself yield strength, often result in the problems such as raw leakage, production and environmental protection are adversely affected.Along with socioeconomic development, oil gas transport efficiency requirements is higher, exploit the development trends such as difficulty increase constantly proposes harsher requirement to slab quality.Especially such as casting blank solidification tissue ratio and distribution equiaxial crystal ratio, much researching and analysing and point out, poling lumber recovery and end product quality are had material impact by circle base equiaxial crystal ratio.Therefore, improve strand strand equiaxial crystal ratio, expand Center Equiaxial Crystal district, optimize casting blank solidification structural homogenity just aobvious particularly important.
For 30CrMo tube blank steel, it is bigger that the Gao Ge in steel grades, molybdenum content itself determine strand column crystal prosperity trend；Furthermore, owing to casting blank section is relatively large and for circle base, its specific surface area less strand heat transfer efficiency is lower, and slowly, the control of crystalline structure is more difficult in solidification cooling.In continuous casting production process, strand column crystal is flourishing, and equiaxial crystal ratio is on the low side, often leads to column crystal interdendritic and occurs bonding, forms confined space, and molten steel continues cooled and solidified, volume contraction, and outside molten steel cannot feeding in time and form the defects such as loose, segregation.Loose and the center segregation formed can not all effectively eliminate in subsequent rolling process process, affects product quality.As metallurgical work studies, improve the emphasis that 30CrMo circular pipe blank Inner Quality of Billet is research, especially as improved 30CrMo circular pipe blank strand equiaxial crystal ratio.
Patent CN102021488A discloses a kind of steel for nuclear-island seamless steel tube and production method thereof.The steel for nuclear-island seamless steel tube of the present invention, its chemical composition is by weight percentage: 0 < C≤0.20%, 0.10%≤Si≤0.35%, 0.80%≤Mn≤1.60%, 0 < P≤0.020%, 0 < S≤0.015%, 0 < Cr≤0.25%, 0 < Ni≤0.50%, 0 < Cu≤0.18%, 0 < Mo≤0.10%, 0 < V≤0.06%, 0.020%≤Al≤0.050%, 0 < Sn≤0.030%, Fe is surplus.The steel for nuclear-island seamless steel tube of this invention meets the condition of carbon equivalent (Ceq=C+Mn/6+ (Cr+Mo+V)/5+ (Ni+Cu)/15)≤0.48, control the essential element carbon and manganese content of steel, stabilized steel pipe die intends the tensile property after hidden lino removal, it is ensured that body and simulation hidden lino removal sample tensile property meet technical standard requirement simultaneously.Residual elements nickel is added as alloying element, improves steel for nuclear-island seamless steel tube low-temperature impact toughness, meet its 0 DEG C ,-20 DEG C impact flexibility requirements.But concrete grammar φ 350mm section being produced to the control of bigger specification 30CrMo circular pipe blank equiaxial crystal ratio is not directed to.The open a kind of hot-rolled steel pipe continuous casting round billet hot charging method and system of CN101984093A, its method includes step: the molten steel casting after refine becomes continuous cast round billets；On continuous cast round billets production line, continuous cast round billets is cut into multiple lengths by flame gun, forms hot continuous cast round billets；The hot continuous cast round billets of multiple lengths at least has two flow directions, and the hot continuous cast round billets of Part I enters into preheating furnace preheating or insulation by the first circle base rollgang, then passes through the second circle base rollgang and delivers to high temperature furnace heating；The hot continuous cast round billets of Part II is directly sent to high temperature furnace heating by the second circle base rollgang；The hot continuous cast round billets delivering to high temperature furnace heating is cut into cut lengths by hot saw equipment hot saw；The continuous cast round billets that hot saw is cut into cut lengths sends to heat centering, perforation, tube rolling；Subsequently enter next procedure.This invention makes full use of the heat of hot continuous cast round billets, saves a large amount of fuel；Reduce equipment needed thereby and Factory Building simultaneously, reduce found the factory investment and maintenance of equipment expense.But producing bigger specification 30CrMo circular pipe blank equiaxial crystal ratio for φ 350mm section to control, the concrete grammar improving Inner Quality of Billet is not directed to.CN103537642A discloses a kind of new method controlling continuous cast round billets machine Casting speed, and the control method of continuous casting billet pulling rate is divided into two stages.First stage, before continuous casting billet disengagement dummy bar head (about more than 10 30 minutes), the casting speed control of strand is formulated by traditional method and is determined according to the actual degree of superheat of Metal in Tundish.Second stage, after strand disengages dummy bar head, the Actual Casting Speed of strand should determine in the casting billet surface actual temperature of straightening section by strand, namely strand Actual Casting Speed data are adjusted according to the surface real data of straightening section place strand, strand is made to depart from this dangerous temperature of theoretical 723 DEG C-912 DEG C of brittleness temperature region as early as possible interval, probability that casting billet surface that strand due to self tissue inter-variable cause easily crack is greatly decreased, and next takes into account molten steel temperature in tundish.It is easy to be effectively improved or substantially solve arc large round billet conticaster billet surface crackle easily lead to a phenomenon, under the premise ensureing slab quality, improve conticaster integral production efficiency greatly, improve strand lumber recovery further, better improve great circle surface quality of continuously cast slab.But for φ 350mm section production bigger specification 30CrMo circular pipe blank equiaxial crystal ratio control, promote casting blank solidification structural homogenity, the concrete grammar of compactness is not directed to.
Summary of the invention
When the technical problem to be solved is to provide a kind of production 30CrMo circular pipe blank steel strand, it is effectively improved the center segregation control method of the 30CrMo circular pipe blank steel strand of center segregation parameter.
The technical solution adopted for the present invention to solve the technical problems is: the center segregation control method of 30CrMo circular pipe blank steel strand, comprises the steps:
A, being first converter smelting process, wherein converter terminal is controlled by carbon content >=0.05%, phosphorus content≤0.010%, and outlet temperature scope presses 1670 DEG C～1690 DEG C controls；
Secondly b, it is LF stove refined molten steel technique, wherein utilizing LF refine whole process Argon to stir, and forbid occur that molten steel turns over greatly phenomenon, during departures, Als is controlled according to 0.040%～0.060%, described refine terminates rear Argon >=5min, and out-station temperature is controlled by 1590～1620 DEG C；
Secondly c, it is RH refinery practice, wherein argon flow amount is controlled by 1150～1450NL/min, the process time of vacuum < 3mbar is more than or equal to 10min, when RH sets off, described Als is controlled by 0.030%～0.055%, application of vacuum terminates rear argon blowing time >=5min, and out-station temperature span of control is 1560～1580 DEG C；
D, finally it is continuous casting steel technique, wherein: the stir current that crystallizer electromagnetism stirs is 350～400A, frequency 2～4Hz；Solidification end stirring parameter is stir current 200～300A, frequency 6.0～8.0Hz；Degree of superheat span of control is 15～35 DEG C；Casting speed control is at 0.75～1.00m/min；Two cold specific waters control at 0.21～0.29/kgSteel。
Further, in described step b, the argon flow amount of omnidistance Argon stirring fluctuates slightly by molten steel.
Further, in described step d, ensure green shell homoepitaxial in crystallizer and to reach the crystallizer cooling span of control of required thickness scope be 2350～2550L/min.
The invention has the beneficial effects as follows: the present invention it is critical only that the method by " M-EMS+solidification end electromagnetic agitation " M+F-EMS, realize the more significant bigger specification 30CrMo circular pipe blank solidified structure of strand column crystal prosperity trend is controlled, thus realizing the center segregation of circular pipe blank and steel strand is controlled.Fusing, by forcing to drive the flowing of mushy zone molten steel, is washed away by solidification end electromagnetic agitation by columanar structure, it is suppressed that column crystal grows, thus improving the control of center segregation parameter.Present invention is particularly suitable for producing 30CrMo circular pipe blank and the steel strand of φ 350mm section.
Detailed description of the invention
The technical solution adopted for the present invention to solve the technical problems is: the center segregation control method of 30CrMo circular pipe blank steel strand, comprise the steps: a, first for converter smelting process, wherein converter terminal is controlled by carbon content >=0.05%, phosphorus content≤0.010%, and outlet temperature scope presses 1670 DEG C～1690 DEG C controls；Secondly b, it is LF stove refined molten steel technique, wherein utilizing LF refine whole process Argon to stir, and forbid occur that molten steel turns over greatly phenomenon, during departures, Als is controlled according to 0.040%～0.060%, described refine terminates rear Argon >=5min, and out-station temperature is controlled by 1590～1620 DEG C；Secondly c, it is RH refinery practice, wherein argon flow amount is controlled by 1150～1450NL/min, the process time of vacuum < 3mbar is more than or equal to 10min, when RH sets off, described Als is controlled by 0.030%～0.055%, application of vacuum terminates rear argon blowing time >=5min, and out-station temperature span of control is 1560～1580 DEG C；D, finally it is continuous casting steel technique, wherein: the stir current that crystallizer electromagnetism stirs is 350～400A, frequency 2～4Hz；Solidification end stirring parameter is stir current 200～300A, frequency 6.0～8.0Hz；Degree of superheat span of control is 15～35 DEG C；Casting speed control is at 0.75～1.00m/min；Two cold specific waters control at 0.21～0.29/kgSteel.Therein, Als refers to dissolved aluminum.
When producing 30CrMo circular pipe blank and steel strand, the steel grade chemical constituent that it adopts is by weight percentage: C:0.27%～0.32%, Si:0.20%～0.35%, Mn:0.45%～0.65%, P≤0.020%, S≤0.010%, V≤0.015%, Cr::0.85%～1.05%, Mo:0.17%～0.24%, Cu≤0.15%, Ni≤0.20%, Alt:0.020%～0.040%, residual elements require: Nb≤0.010%, Ti≤0.010%, B≤0.005%, and V+Nb+Ti+B+Zr≤0.15%；As≤0.015%, Sn≤0.010%Sb≤0.010%, Pb≤0.008%, Bi≤0.010%, and As+Sn+Sb+Pb+Bi≤0.045%, surplus is Fe.Adopt the 30CrMo circle base steel continuous casting billet that this method produces, its equiaxial crystal ratio is effectively controlled, casting blank solidification tissue is effectively improved, and loose grading improves, equiax crystal region area expands, circle base central area compactness effectively improves, and mill bar quality controls good and stable.Under normal circumstances, in continuous casting process, casting blank solidification tissue presents the crystallizer tissue regions in " chill fine grained region, columnar zone, Center Equiaxial Crystal district " from casting billet surface to center.Improve strand equiaxial crystal ratio for improving slab quality, improve strand central area consistency, current metallurgy industry emerges kinds of processes technology, the method wherein improving strand center porosity just has electromagnetic agitating technology and solidification end Reduction Technology, and for circle base, for ensureing the regular demand of strand overall dimensions, do not use solidification end Reduction Technology.Therefore, electromagnetic agitation is currently used effect comparatively substantially one of technological means.
The present invention is formulated by the rational degree of superheat and pulling rate match control and intensity of secondary cooling, is the key of casting blank solidification heat transfer control, the key that namely center segregation of casting blank controls.
Embodiment
Certain steel mill adopts 120t converter smelting → LF stove refine → RH refine → tetra-machine four to flow casting machine φ 350mm section continuous casting and produces 30CrMo circular pipe blank.When bessemerizing end, aim carbon is 0.05% be controlled, and terminal phosphorus is 0.006%, and outlet temperature controls at 1690 DEG C.
Molten steel arrives LF refining furnace place, carries out Argon molten steel and slightly fluctuates, and does not occur turning over greatly phenomenon, and departures Als controls to be 0.040%, and molten steel is carried out soft blow argon after terminating by refine, and argon blowing time is after 6.5min, LF process terminates, and constant temperature is 1590 DEG C.
After molten steel arrives at a station, RH refine Argon argon flow amount is 1450NL/min control, and process time 11min, the RH departures Als of vacuum < 3mbar is 0.030%, and application of vacuum terminates rear Argon 5min, and out-station temperature controls at 1580 DEG C.
RH application of vacuum is allocated and transported after terminating and is flowed casting machine φ 350mm section to four machines four and carry out molten steel casting, and actual control of the critical technical parameter relevant to application claims is: M-EMS: stir current 370A, stirring frequency 2.0Hz；Solidification end electromagnetic agitation: stir current 200A, stirring frequency 8.0Hz；The actual casting process degree of superheat of molten steel controls at 15～27 DEG C；Pulling rate is 1.00m/min；Crystallizer cooling controls at 2550L/min；Two cold specific waters control at 0.21/kgSteel。
After above-mentioned technological invention is stably used, slab quality is well controlled, and strand low power center segregation testing result is 0 grade；Spectrum direct-reading segregation testing result is 1.03～1.04.
Claims (3)
- The center segregation control method of 1.30CrMo circular pipe blank steel strand, it is characterised in that comprise the steps:A, being first converter smelting process, wherein converter terminal is controlled by carbon content >=0.05%, phosphorus content≤0.010%, and outlet temperature scope presses 1670 DEG C～1690 DEG C controls；Secondly b, it is LF stove refined molten steel technique, wherein utilizing LF refine whole process Argon to stir, and forbid occur that molten steel turns over greatly phenomenon, during departures, Als is controlled according to 0.040%～0.060%, described refine terminates rear Argon >=5min, and out-station temperature is controlled by 1590～1620 DEG C；Secondly c, it is RH refinery practice, wherein argon flow amount is controlled by 1150～1450NL/min, the process time of vacuum < 3mbar is more than or equal to 10min, when RH sets off, described Als is controlled by 0.030%～0.055%, application of vacuum terminates rear argon blowing time >=5min, and out-station temperature span of control is 1560～1580 DEG C；D, finally it is continuous casting steel technique, wherein: the stir current that crystallizer electromagnetism stirs is 350～400A, frequency 2～4Hz；Solidification end stirring parameter is stir current 200～300A, frequency 6.0～8.0Hz；Degree of superheat span of control is 15～35 DEG C；Casting speed control is at 0.75～1.00m/min；Two cold specific waters control at 0.21～0.29/kgSteel。
- 2. the center segregation control method of 30CrMo circular pipe blank steel strand as claimed in claim 1, it is characterised in that: in described step b, the argon flow amount of omnidistance Argon stirring fluctuates slightly by molten steel.
- 3. the center segregation control method of 30CrMo circular pipe blank steel strand as claimed in claim 1, it is characterised in that: in described step d, ensure green shell homoepitaxial in crystallizer and to reach the crystallizer cooling span of control of required thickness scope be 2350～2550L/min.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110899330A (en) * | 2019-10-29 | 2020-03-24 | 邯郸钢铁集团有限责任公司 | Center crack control process for large-size 42CrMo round steel with thickness of more than 70mm |
| US10919088B2 (en) | 2017-02-20 | 2021-02-16 | Abb Schweiz Ag | Method and stirring system for controlling an electromagnetic stirrer |
| CN113092712A (en) * | 2021-02-26 | 2021-07-09 | 邯郸钢铁集团有限责任公司 | Quality evaluation method for casting blank of exposed part of outer plate for high-end automobile |
| CN114985694A (en) * | 2022-06-22 | 2022-09-02 | 芜湖新兴铸管有限责任公司 | Method for reducing carbon segregation range of medium carbon steel billet |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61140357A (en) * | 1984-12-11 | 1986-06-27 | Kobe Steel Ltd | Electromagnetic stirring method of weakly deoxidized steel in continuous casting of slab |
| CN101701277A (en) * | 2009-11-25 | 2010-05-05 | 天津钢铁集团有限公司 | Method for smelting steel round blank of air cylinder by convertor process |
| CN102277534A (en) * | 2011-07-29 | 2011-12-14 | 攀钢集团有限公司 | Hot rolled steel section for gas cylinders and production method thereof |
| CN105215310A (en) * | 2015-11-17 | 2016-01-06 | 攀钢集团攀枝花钢铁研究院有限公司 | A kind of method that big cross section Properties of Heavy Rail Steel strand center porosity controls |
-
2016
- 2016-03-23 CN CN201610172935.7A patent/CN105772666B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61140357A (en) * | 1984-12-11 | 1986-06-27 | Kobe Steel Ltd | Electromagnetic stirring method of weakly deoxidized steel in continuous casting of slab |
| CN101701277A (en) * | 2009-11-25 | 2010-05-05 | 天津钢铁集团有限公司 | Method for smelting steel round blank of air cylinder by convertor process |
| CN102277534A (en) * | 2011-07-29 | 2011-12-14 | 攀钢集团有限公司 | Hot rolled steel section for gas cylinders and production method thereof |
| CN105215310A (en) * | 2015-11-17 | 2016-01-06 | 攀钢集团攀枝花钢铁研究院有限公司 | A kind of method that big cross section Properties of Heavy Rail Steel strand center porosity controls |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10919088B2 (en) | 2017-02-20 | 2021-02-16 | Abb Schweiz Ag | Method and stirring system for controlling an electromagnetic stirrer |
| CN110899330A (en) * | 2019-10-29 | 2020-03-24 | 邯郸钢铁集团有限责任公司 | Center crack control process for large-size 42CrMo round steel with thickness of more than 70mm |
| CN113092712A (en) * | 2021-02-26 | 2021-07-09 | 邯郸钢铁集团有限责任公司 | Quality evaluation method for casting blank of exposed part of outer plate for high-end automobile |
| CN113092712B (en) * | 2021-02-26 | 2023-05-09 | 邯郸钢铁集团有限责任公司 | Method for evaluating quality of casting blank of outer plate exposed part for high-end automobile |
| CN114985694A (en) * | 2022-06-22 | 2022-09-02 | 芜湖新兴铸管有限责任公司 | Method for reducing carbon segregation range of medium carbon steel billet |
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