CN107299278B - A kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt steel making method - Google Patents
A kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt steel making method Download PDFInfo
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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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
- C21C5/30—Regulating or controlling the blowing
- C21C5/35—Blowing from above and through the bath
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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
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/06—Deoxidising, e.g. killing
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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
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/06—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of rods or wires
- C21D8/065—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of rods or wires of ferrous alloys
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
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Abstract
A kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt steel making method, includes the following steps：Top and bottom complex blowing basic bessemer converter just refining, LF refining furnace refining, the degassing of VD vacuum drying ovens, large round billet circular-arc type continuous casting machine continuous casting, steel rolling heating, dephosphorization and iron oxide scale, roll, enter to cheat slow cooling.The present invention has three obdurability, delayed fracture resistance and cold deformation aspect exploitation designs in mind, and after round steel bulk heat treatmet, performance indicator reaches Rm >=950Mpa, Re >=830Mpa, A >=20%, Z >=60%, KV2 (- 101 DEG C) >=30J.
Description
Technical field
The present invention relates to steelmaking technical field more particularly to a kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt steel making sides
Method.
Background technology
The grade bolts such as L43 high-strength bolt in Large-scale Wind Turbines is largely used, more powerful to adapt to
The autonomous Design of wind power generating set is developed, and is ensured the operational reliability of entire wind power generating set, is met wind-powered electricity generation manufacturing enterprise
Demand.Basis of the fastener as Wind turbines, in the connection of host, blade, pylon and reduction box, with wind-driven generator
Group subjects additional axial tension (alternation) load, lateral shear (alternation) load or the bending load being thus combined together
The effect of lotus, also shock loading and long-term field are on active service sometimes, the condition of bad environments.Good cold pier performance is needed,
High tensile strength and plasticity, toughness, higher fatigue resistance and repeat impact stretch resistance have sufficiently low delayed fracture
Sensibility and low tough crisp conversion temperature.In the latest 20 years, both at home and abroad substantially using 35VB, 35CrMo, 42CrMo, American Standard B7 and
The steel grades such as 40CrNiMoA produce, and manufacture wind-powered electricity generation high-strength bolt, -101 DEG C of ballistic works of big dimension stock are difficult to stably reach
27J requirements above.Into 21st century, especially in recent years, as domestic high-power wind turbine generating set is gone into operation successively,
To ensure that entire unit stability in the process of running and safety, some domestic wind-powered electricity generation producers are attempted to use the big specifications of L43
Steel manufacture high intensity, low temperature resistant bolt, but -101 DEG C of low-temperature impact work wild effects annoying always the research and development of product into
Journey.
Currently, the good market prospect of 42CrNi2Mo steel, but the steel grade production technology difficulty is very big, and advise greatly
The production of lattice material is more difficult to, and puzzle wind power high-strength bolt steel manufacturing enterprise for a long time.Technical bottleneck shows as two aspects：First, advising greatly
- 101 DEG C of ballistic works of lattice material are difficult to stablize guarantee；Second is that because the steel contains higher Ni elements, contain Cr elements simultaneously, causes thick
Strip plate dephosphorization is difficult, the surface quality of steel outstanding problem that steel thereby result in.42CrNi2Mo steel grade chemical compositions are compared with national standard
The Ni of 40CrNiMoA is increased to 1.65~2.00% by 1.25~1.65%, and other elements have adjustment.It is generated in steel containing Ni brilliant
Between selective oxidation, make FeO fayalites or its eutectic along the wedge shaped immersion metallic matrix of intergranular, disperseed iron scale with
The stress of metal circle, to improve the iron scale adhesiveness of the steel containing Ni, when Ni, Cr coexist, thickness obviously increases, and makes
Difficult at strip plate dephosphorization, this is also the long-standing technical barrier in this field.
Therefore, a kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt steel making method is developed, not only there is urgent research
Value, it may have good economic benefit and commercial application potentiality, where this power that exactly present invention is accomplished and basis.
Invention content
In order to overcome the defect of the prior art as indicated above, the present inventor to have made intensive studies this, paying
After a large amount of creative works, so as to complete the present invention.
Specifically, the technical problem to be solved by the present invention is to：A kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt is provided
With steel making method.
In order to solve the above technical problems, the technical scheme is that：
A kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt steel making method, includes the following steps：Top and bottom complex blowing alkalinity turns
Refining, LF refining furnace refining, the degassing of VD vacuum drying ovens, large round billet circular-arc type continuous casting machine continuous casting, steel rolling heating, dephosphorization and iron oxide at the beginning of stove
Scale rolls, enters to cheat slow cooling.
In the present invention, as a kind of perferred technical scheme, the concrete technology that the top and bottom complex blowing basic bessemer converter just refines is：
Using high-quality molten iron as main material, and it is equipped with pig iron composition steel-making primary raw material, liquid iron charging ratio reaches 80%, blows
" double slags " method dephosphorization, terminal point control (C+Mn) content wt >=0.18%, P content wt≤0.010% of tapping are used during refining；Go out
Add SiCaBaAl 1.0kg/t steel, steel-core-aluminium 2.0kg/t steel-deoxidizings when 15~20t of steel, iron alloy material, carburant, slag charge are subsequent
It is added in packet, the tapping later stage uses argon gas strong mixing, with uniform temperature and ingredient, and deoxidation products is promoted to float.
Iron alloy material includes fero-manganesesilicon, ferrochrome, nickel plate and molybdenum-iron.
Wherein, 2/3 quantity of nickel plate is added in first furnace, and 1/3 quantity is added in tapping process.
Nickel plate carries out 650-750 DEG C of heat preservation, and the time is more than 4 hours expansion hydrogen annealings.
Slag charge includes the mixture of lime, pro-molten refining slag and fluorite.
In the present invention, as a kind of perferred technical scheme, the concrete technology of the LF refining furnace refining is：Before refining furnace
Phase calcium carbide and silicon carbide diffusive deoxidation, form white slag as early as possible, and the dual alkalinity R controls of white slag are 4~9%, chemical composition control
Target processed：C, Si contents wt is controlled by 0.39~0.41%, 0.23~0.27% lower limit；Mn, Cr, Ni, Mo content wt are pressed
0.78%, 0.83%, 1.73%, 0.23% desired value controls；S content wt≤0.010%；Al content wt：0.030~
0.040%；Finishing slag dual alkalinity R2 >=4.0 are refined, the chemical composition wt% of the refining finishing slag is：(FeO+MnO) <
0.60%, CaO 50~65%, SiO25~18%, MgO 0.2~3.0%, Al2O325~30%, S 0.30~0.60%.
In the present invention, as a kind of perferred technical scheme, the concrete technology of the VD vacuum drying ovens degassing is：1650 ±
10 DEG C, vacuum degree be less than 67Pa under keep 15min or more carry out VD Fruit storages, after treatment feed 1.5~2.0m/
T CaSi core-spun yarns carry out denaturation treatment to molten steel, while the protection covering that charring rice husk carries out molten steel is added, argon gas before bull ladle
15~30min of soft stirring, 1550 ± 15 DEG C of bull ladle temperature.
In the present invention, as a kind of perferred technical scheme, the concrete technology of the large round billet circular-arc type continuous casting machine continuous casting is：
Big packet long nozzle uses Ar seal apparatus, flows blowing argon to big Baogang, the degree of superheat is at 25~40 DEG C, during Φ 350mm round billets use
Carbon mould flux, pulling rate are 0.48 ± 0.2m/min, and conticaster uses M-EMS parameter 3Hz/250A, strand to exist
After the infrared Length-fixing cutting of line, high temperature is clamped into hole slow cooling.
In the present invention, as a kind of perferred technical scheme, the concrete technology of the steel rolling heating is：Φ 350mm steel billets
It is controlled at≤800 DEG C using preheating section temperature using walking beam furnace, heats one section of 1100-1180 DEG C of temperature, heat two sections
Temperature is controlled at 1180-1220 DEG C, and two sections of heating and soaking zone soaking time are more than 3 hours, high temperature section (one section of heating and heating
Two sections) total heating time is more than 6 hours heating process.
In the present invention, as a kind of perferred technical scheme, the concrete technology of the dephosphorization and iron oxide scale is：It is logical
After crossing the high pressure water dephosphorization of 20-24MPa, using the broken iron oxide scale for bonding fastening of manipulator transverse shifting, roughing before open rolling
When the 2nd, 4,6 passage double steel methods reject side scale.
In the present invention, as a kind of perferred technical scheme, the concrete technology of the rolling is：Φ 350mm round billets use
After the intermediate square billet of blooming mill production 180mm × 220mm of Φ 1350mm, it is rolled into the steel of 88~Φ of Φ 100mm, steel pressure
Contracting ensure that the inherent quality of steel than > 12.
It is as a kind of perferred technical scheme, described to enter to cheat the concrete technology of slow cooling and be in the present invention：Steel rolling terminates
Enter to cheat slow cooling mode using 500 DEG C of > afterwards, further goes de-stress.
In the present invention, nickel can improve the intensity of steel and improve its plasticity and toughness；Nickel does not form carbonization in steel
Object can only be solid-solution in austenite and ferrite, play crystal grain thinning, reinforced ferrite, improve toughness, especially improve low temperature punching
Hit the effect for absorbing energy；The quenching degree of steel can be increased again simultaneously, this higher to mechanical property requirements and uniform big section wind
Electric high-strength bolt effect is preferable.
Due to using the technology described above, the present invention has the advantages that：
One, the essential elements target component such as C, Si, Mn, Cr, Mo, Ni in steel is designed, integrated performance index is improved；Control exists
More conventional narrower interval range, steel uniformity is good and product performance index stability is high；The control of TAl contents 0.025%~
0.035%, crystal grain thinning.
Two, the present invention use double slag operation of converter and LF ladle refining high alkalinity slag systems, no dephosphorization, desiliconization and desophorization for hot metal (dephosphorization,
Desiliconization, desulfurization) under the conditions of, realize low P, low S control；Using VD vacuum outgas and whole argon for protecting pouring, to H, O, N etc.
Impurity content is controlled, and nonmetallic inclusionsin steel quantity is reduced, and is promoted fine dispersion, is improved the low temperature ductile-brittle transiton of steel
Temperature.
Three, the present invention produces continuous casting billet using continuous casting process, and steel densification is effectively improved using electromagnetic agitating technology
Degree and component segregation.
Four, the present invention combines the innovation containing higher Ni and Cr elements red heat steel billet difference base type to use combined type de-scaling mode：
Manipulator pushes the broken attachment squama of steel billet transverse shifting before high-pressure water descaling+steel billet open rolling after the hot base of circle is come out of the stove
The 2nd, 4,6 passage double steel method de-scaling of piece+roughing.
The present invention has three obdurability, delayed fracture resistance and cold deformation aspect exploitation designs, round steel overall thermal in mind
After processing, performance indicator reaches Rm >=950Mpa, Re >=830Mpa, A >=20%, Z >=60%, KV2 (- 101 DEG C) >=30J.
Specific implementation mode
With reference to specific embodiment, the present invention is further described.But the purposes and mesh of these exemplary embodiments
Be only used for enumerating the present invention, any type of any restriction not is constituted to the real protection scope of the present invention, it is more non-to incite somebody to action this
The protection domain of invention is confined to this.
Embodiment 1
A kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt steel making method, includes the following steps：
Top and bottom complex blowing basic bessemer converter just refines：Converter is equipped with the composition steel-making of the 5t pig iron and uses using the high-quality molten iron of 72t as main material
Primary raw material, liquid iron charging ratio reach 80%, use " double slags " method dephosphorization, terminal point control (C+Mn) content wt to be in converting process
0.18%, tapping P content wt is 0.010%；Add SiCaBaAl1.0kg/t steel, steel-core-aluminium 2.0kg/t steel-deoxidizings when tapping 15t,
(iron alloy material includes fero-manganesesilicon, ferrochrome, nickel plate and molybdenum-iron to iron alloy material；Wherein, 2/3 quantity of nickel plate is added in first furnace, and 1/
3 quantity are added in tapping process, and nickel plate carries out 650 DEG C of heat preservations, and the time is 4.5 hours expansion hydrogen annealings), carburant,
Packet is then added in slag charge (slag charge includes the mixture of 300kg/ hearthstones ash, 500kg/ stoves pro-molten refining slag and 100kg/ stove fluorites)
In, the tapping later stage uses argon gas strong mixing, with uniform temperature and ingredient, and deoxidation products is promoted to float；
LF refining furnace refines：Refining furnace calcium carbide early period and silicon carbide diffusive deoxidation form white slag, the binary of white slag as early as possible
Basicity R control is 4, chemical Composition Control target：C, Si contents wt presses 0.39%, the control of 0.23% lower limit；Mn, Cr, Ni, Mo contain
Wt is measured to control by 0.78%, 0.83%, 1.73%, 0.23% desired value；S contents wt is 0.010%；Al content wt is
0.030%, surplus is Fe and other inevitable impurity；It is 4.0 to refine finishing slag dual alkalinity R2, the change of the refining finishing slag
Learning composition wt% is：(FeO+MnO) it is 0.5%, CaO 65%, SiO25%, MgO 0.2%, Al2O329%, S 0.30%.
VD vacuum drying ovens deaerate：15min is kept to carry out VD Fruit storages, processing knot at 1640 DEG C, vacuum degree 67Pa
1.5m/t CaSi core-spun yarns are fed after beam, denaturation treatment is carried out to molten steel, while charring rice husk is added carries out the protection of molten steel and covering
It covers, the soft stirring 15min of argon gas before bull ladle, 1535 DEG C of bull ladle temperature.
Large round billet circular-arc type continuous casting machine continuous casting：Big packet long nozzle uses Ar seal apparatus, flows blowing argon, the degree of superheat to big Baogang
At 25 DEG C, carbon mould flux during Φ 350mm round billets use, pulling rate 0.28m/min, conticaster is using M-EMS
Parameter 3Hz/250A, after the infrared Length-fixing cutting of line, high temperature is clamped into hole slow cooling strand.
Steel rolling is heated：Φ 350mm steel billets are controlled using preheating section temperature at 800 DEG C using walking beam furnace, heating one
1100 DEG C of Duan Wendu heats two sections of temperature controls at 1180 DEG C, and two sections of heating and soaking zone soaking time are 3.5 hours, high temperature
The heating process that section (two sections of one section of heating and heating) total heating time is 6.5 hours.
Dephosphorization and iron oxide scale：It is broken using manipulator transverse shifting before open rolling after the high pressure water dephosphorization of 20MPa
The iron oxide scale for bonding fastening, the 2nd, 4,6 passage double steel methods reject side scale when roughing.
Rolling：After intermediate square billet of the Φ 350mm round billets using blooming mill production 180mm × 220mm of Φ 1350mm, rolling
At the steel of Φ 88mm, steel compression ratio > 12 ensure that the inherent quality of steel.
Enter to cheat slow cooling：Enter to cheat slow cooling mode using 510 DEG C after steel rolling, further goes de-stress.
Steel performance index manufactured in the present embodiment reaches Rm955Mpa, Re835Mpa, A 20%, Z 65%, KV2 (-
101℃)30J。
Embodiment 2
A kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt steel making method, includes the following steps：
Top and bottom complex blowing basic bessemer converter just refines：Converter is equipped with the composition steel-making of the 8t pig iron and uses using the high-quality molten iron of 72t as main material
Primary raw material, liquid iron charging ratio reach 80%, use " double slags " method dephosphorization, terminal point control (C+Mn) content wt to be in converting process
0.2%, tapping P content wt is 0.009%；Add SiCaBaAl1.0kg/t steel, steel-core-aluminium 2.0kg/t steel-deoxidizings when tapping 20t,
(iron alloy material includes fero-manganesesilicon, ferrochrome, nickel plate and molybdenum-iron to iron alloy material；Wherein, 2/3 quantity of nickel plate is added in first furnace, and 1/
3 quantity are added in tapping process, and nickel plate carries out 750 DEG C of heat preservations, and the time is 5 hours expansion hydrogen annealings), carburant, slag
Packet is then added in material (slag charge includes the mixture of 300kg/ hearthstones ash, 500kg/ stoves pro-molten refining slag and 100kg/ stove fluorites)
In, the tapping later stage uses argon gas strong mixing, with uniform temperature and ingredient, and deoxidation products is promoted to float；
LF refining furnace refines：Refining furnace calcium carbide early period and silicon carbide diffusive deoxidation form white slag, the binary of white slag as early as possible
Basicity R control is 9, chemical Composition Control target：C, Si contents wt presses 0.41%, the control of 0.27% lower limit；Mn, Cr, Ni, Mo contain
Wt is measured to control by 0.78%, 0.83%, 1.73%, 0.23% desired value；S contents wt is 0.010%；Al content wt：
0.040%, surplus is Fe and other inevitable impurity；It is 4.5 to refine finishing slag dual alkalinity R2, the change of the refining finishing slag
Learning composition wt% is：(FeO+MnO) 0.4%, CaO 50%, SiO218%, MgO 3.0%, Al2O328%, S 0.60%.
VD vacuum drying ovens deaerate：15min is kept to carry out VD Fruit storages, processing under being 67Pa in 1660 DEG C, vacuum degree
After feed 2.0m/t CaSi core-spun yarns denaturation treatment carried out to molten steel, while the protection that charring rice husk carries out molten steel is added
It covers, the soft stirring 30min of argon gas before bull ladle, 1565 DEG C of bull ladle temperature.
Large round billet circular-arc type continuous casting machine continuous casting：Big packet long nozzle uses Ar seal apparatus, flows blowing argon, the degree of superheat to big Baogang
At 40 DEG C, carbon mould flux during Φ 350mm round billets use, pulling rate 0.68m/min, conticaster is using M-EMS
Parameter 3Hz/250A, after the infrared Length-fixing cutting of line, high temperature is clamped into hole slow cooling strand.
Steel rolling is heated：Φ 350mm steel billets are controlled using preheating section temperature at 850 DEG C using walking beam furnace, heating one
1180 DEG C of Duan Wendu heats two sections of temperature controls at 1220 DEG C, and two sections of heating and soaking zone soaking time are 4 hours, high temperature section
The heating process that (two sections of one section of heating and heating) total heating time is 7 hours.
Dephosphorization and iron oxide scale：It is broken using manipulator transverse shifting before open rolling after the high pressure water dephosphorization of 24MPa
The iron oxide scale for bonding fastening, the 2nd, 4,6 passage double steel methods reject side scale when roughing.
Rolling：After intermediate square billet of the Φ 350mm round billets using blooming mill production 180mm × 220mm of Φ 1350mm, rolling
At the steel of Φ 95mm, steel compression ratio > 12 ensure that the inherent quality of steel.
Enter to cheat slow cooling：Enter to cheat slow cooling mode using 515 DEG C after steel rolling, further goes de-stress.
Steel performance index manufactured in the present embodiment reaches Rm 950Mpa, Re 832Mpa, A 21%, Z 62%, KV2 (-
101℃)32J。
Embodiment 3
A kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt steel making method, includes the following steps：
Top and bottom complex blowing basic bessemer converter just refines：Converter is equipped with the composition steel-making of the 7t pig iron and uses using the high-quality molten iron of 72t as main material
Primary raw material, liquid iron charging ratio reach 80%, and converting process takes the circumstances into consideration to adjust the additions such as lime, dolomite, ore, using " double
Slag " method dephosphorization, terminal point control (C+Mn) content wt are 0.18%, and tapping P content wt is 0.010%；Add when tapping 18t
SiCaBaAl 1.0kg/t steel, steel-core-aluminium 2.0kg/t steel-deoxidizings, (iron alloy material includes fero-manganesesilicon, ferrochrome, nickel plate to iron alloy material
And molybdenum-iron；Wherein, 2/3 quantity of nickel plate is added in first furnace, and 1/3 quantity is added in tapping process, and nickel plate carries out 700
DEG C heat preservation, the time is 5 hours expansion hydrogen annealings), carburant, (slag charge includes 300kg/ hearthstones ash, 500kg/ stoves fritting essence to slag charge
Refine slag and 100kg/ stove fluorites mixture) then be added packet in, tapping the later stage use argon gas strong mixing, with uniform temperature and at
Point, and deoxidation products is promoted to float；
LF refining furnace refines：Refining furnace calcium carbide early period and silicon carbide diffusive deoxidation form white slag, the binary of white slag as early as possible
Basicity R control is 8.38, chemical Composition Control target：C, Si contents wt presses 0.40%, the control of 0.25% lower limit；Mn,Cr,Ni,
Mo contents wt is controlled by 0.78%, 0.83%, 1.73%, 0.23% desired value；S contents wt is 0.010%；Al content wt：
0.035%, surplus is Fe and other inevitable impurity；It is 6.49 to refine finishing slag dual alkalinity R2, the refining finishing slag
Chemical composition wt% is：FeO 0.30%, CaO 60.07%, SiO29.25%, MgO 0.63%, Al2O328.56%, MnO
0.15%, S 0.502%, surplus are other inevitable impurity.
VD vacuum drying ovens deaerate：20min is kept to carry out VD Fruit storages, processing knot at 1650 DEG C, vacuum degree 65Pa
1.8m/t CaSi core-spun yarns are fed after beam, denaturation treatment is carried out to molten steel, while charring rice husk is added carries out the protection of molten steel and covering
It covers, the soft stirring 20min of argon gas before bull ladle, 1550 DEG C of bull ladle temperature.
Large round billet circular-arc type continuous casting machine continuous casting：Big packet long nozzle uses Ar seal apparatus, flows blowing argon, the degree of superheat to big Baogang
At 35 DEG C, carbon mould flux during Φ 350mm round billets use, pulling rate 0.48m/min, conticaster is using M-EMS
Parameter 3Hz/250A, after the infrared Length-fixing cutting of line, high temperature is clamped into hole slow cooling strand.
Steel rolling is heated：Φ 350mm steel billets are controlled using preheating section temperature at 850 DEG C using walking beam furnace, heating one
1150 DEG C of Duan Wendu heats two sections of temperature controls at 1200 DEG C, and two sections of heating and soaking zone soaking time are 5 hours, high temperature section
The heating process that (two sections of one section of heating and heating) total heating time is 8 hours.
Dephosphorization and iron oxide scale：It is broken using manipulator transverse shifting before open rolling after the high pressure water dephosphorization of 22MPa
The iron oxide scale for bonding fastening, the 2nd, 4,6 passage double steel methods reject side scale when roughing.
Rolling：After intermediate square billet of the Φ 350mm round billets using blooming mill production 180mm × 220mm of Φ 1350mm, rolling
At the steel of Φ 100mm, steel compression ratio > 12 ensure that the inherent quality of steel.
Enter to cheat slow cooling：Enter to cheat slow cooling mode using 550 DEG C after steel rolling, further goes de-stress.
Steel performance index manufactured in the present embodiment reaches Rm 960Mpa, Re 838Mpa, A 24%, Z 65%, KV2 (-
101℃)35J。
Embodiment 4
A kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt steel making method, includes the following steps：
Top and bottom complex blowing basic bessemer converter just refines：Converter is equipped with the composition steel-making of the 6t pig iron and uses using the high-quality molten iron of 72t as main material
Primary raw material, liquid iron charging ratio reach 80%, use " double slags " method dephosphorization, terminal point control (C+Mn) content wt to be in converting process
0.20%, tapping P content wt is 0.007%；Add SiCaBaAl1.0kg/t steel, steel-core-aluminium 2.0kg/t steel-deoxidizings when tapping 16t,
(iron alloy material includes fero-manganesesilicon, ferrochrome, nickel plate and molybdenum-iron to iron alloy material；Wherein, 2/3 quantity of nickel plate is added in first furnace, and 1/
3 quantity are added in tapping process, and nickel plate carries out 660 DEG C of heat preservations, and the time is 4.2 hours expansion hydrogen annealings), carburant,
Slag charge (slag charge includes the mixture of lime, pro-molten refining slag and fluorite) is then added in packet, and the tapping later stage is stirred by force using argon gas
It mixes, with uniform temperature and ingredient, and deoxidation products is promoted to float；
LF refining furnace refines：Refining furnace calcium carbide early period and silicon carbide diffusive deoxidation form white slag, the binary of white slag as early as possible
Basicity R control is 5.35, chemical Composition Control target：C, Si contents wt presses 0.39%, the control of 0.27% lower limit；Mn,Cr,Ni,
Mo contents wt is controlled by 0.78%, 0.83%, 1.73%, 0.23% desired value；S contents wt is 0.010%；Al content wt：
0.032%, surplus is Fe and other inevitable impurity；It is 4.3 to refine finishing slag dual alkalinity R2, the change of the refining finishing slag
Learning composition wt% is：(FeO+MnO) it is 0.5%, CaO 65%, SiO28.5%, MgO 0.5%, Al2O325%, S
0.50%.
VD vacuum drying ovens deaerate：15min is kept to carry out VD Fruit storages, processing knot at 1655 DEG C, vacuum degree 65Pa
1.6m/t CaSi core-spun yarns are fed after beam, denaturation treatment is carried out to molten steel, while charring rice husk is added carries out the protection of molten steel and covering
It covers, the soft stirring 25min of argon gas before bull ladle, 1555 DEG C of bull ladle temperature.
Large round billet circular-arc type continuous casting machine continuous casting：Big packet long nozzle uses Ar seal apparatus, flows blowing argon, the degree of superheat to big Baogang
At 35 DEG C, carbon mould flux during Φ 350mm round billets use, pulling rate 0.38m/min, conticaster is using M-EMS
Parameter 3Hz/250A, after the infrared Length-fixing cutting of line, high temperature is clamped into hole slow cooling strand.
Steel rolling is heated：Φ 350mm steel billets are controlled using preheating section temperature at 800 DEG C using walking beam furnace, heating one
1120 DEG C of Duan Wendu heats two sections of temperature controls at 1190 DEG C, and two sections of heating and soaking zone soaking time are 4 hours, high temperature section
The heating process that (two sections of one section of heating and heating) total heating time is 6.7 hours.
Dephosphorization and iron oxide scale：It is broken using manipulator transverse shifting before open rolling after the high pressure water dephosphorization of 21MPa
The iron oxide scale for bonding fastening, the 2nd, 4,6 passage double steel methods reject side scale when roughing.
Rolling：After intermediate square billet of the Φ 350mm round billets using blooming mill production 180mm × 220mm of Φ 1350mm, rolling
At the steel of Φ 88mm, steel compression ratio > 12 ensure that the inherent quality of steel.
Enter to cheat slow cooling：Enter to cheat slow cooling mode using 510 DEG C after steel rolling, further goes de-stress.
Steel performance index manufactured in the present embodiment reaches Rm 952Mpa, Re 830Mpa, A 20%, Z 60%, KV2 (-
101℃)31J。
Embodiment 5
A kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt steel making method, includes the following steps：
Top and bottom complex blowing basic bessemer converter just refines：Converter is equipped with the composition steel-making of the 7t pig iron and uses using the high-quality molten iron of 72t as main material
Primary raw material, liquid iron charging ratio reach 80%, use " double slags " method dephosphorization, terminal point control (C+Mn) content wt to be in converting process
0.28%, tapping P content wt is 0.008%；Add SiCaBaAl1.0kg/t steel, steel-core-aluminium 2.0kg/t steel-deoxidizings when tapping 18t,
(iron alloy material includes fero-manganesesilicon, ferrochrome, nickel plate and molybdenum-iron to iron alloy material；Wherein, 2/3 quantity of nickel plate is added in first furnace, and 1/
3 quantity are added in tapping process, and nickel plate carries out 750 DEG C of heat preservations, and the time is 4.6 hours expansion hydrogen annealings), carburant,
Slag charge (slag charge includes the mixture of lime, pro-molten refining slag and fluorite) is then added in packet, and the tapping later stage is stirred by force using argon gas
It mixes, with uniform temperature and ingredient, and deoxidation products is promoted to float；
LF refining furnace refines：Refining furnace calcium carbide early period and silicon carbide diffusive deoxidation form white slag, the binary of white slag as early as possible
Basicity R control is 8, chemical Composition Control target：C, Si contents wt presses 0.41%, the control of 0.23% lower limit；Mn, Cr, Ni, Mo contain
Wt is measured to control by 0.78%, 0.83%, 1.73%, 0.23% desired value；S contents wt is 0.007%；Al content wt：
0.032%, surplus is Fe and other inevitable impurity；It is 4.6 to refine finishing slag dual alkalinity R2, the change of the refining finishing slag
Learning composition wt% is：(FeO+MnO) 0.40%, CaO 64%, SiO26%, MgO 2.5%, Al2O326.65%, S
0.45%.
VD vacuum drying ovens deaerate：18min is kept to carry out VD Fruit storages, processing under being 62Pa in 1645 DEG C, vacuum degree
After feed 1.7m/t CaSi core-spun yarns denaturation treatment carried out to molten steel, while the protection that charring rice husk carries out molten steel is added
It covers, the soft stirring 23min of argon gas before bull ladle, 1540 DEG C of bull ladle temperature.
Large round billet circular-arc type continuous casting machine continuous casting：Big packet long nozzle uses Ar seal apparatus, flows blowing argon, the degree of superheat to big Baogang
At 30 DEG C, carbon mould flux during Φ 350mm round billets use, pulling rate 0.28m/min, conticaster is using M-EMS
Parameter 3Hz/250A, after the infrared Length-fixing cutting of line, high temperature is clamped into hole slow cooling strand.
Steel rolling is heated：Φ 350mm steel billets are controlled using preheating section temperature at 800 DEG C using walking beam furnace, heating one
1170 DEG C of Duan Wendu heats two sections of temperature controls at 1210 DEG C, and two sections of heating and soaking zone soaking time are 3.5 hours, high temperature
The heating process that section (two sections of one section of heating and heating) total heating time is 7 hours.
Dephosphorization and iron oxide scale：It is broken using manipulator transverse shifting before open rolling after the high pressure water dephosphorization of 23MPa
The iron oxide scale for bonding fastening, the 2nd, 4,6 passage double steel methods reject side scale when roughing.
Rolling：After intermediate square billet of the Φ 350mm round billets using blooming mill production 180mm × 220mm of Φ 1350mm, rolling
At the steel of Φ 100mm, steel compression ratio > 12 ensure that the inherent quality of steel.
Enter to cheat slow cooling：Enter to cheat slow cooling mode using 520 DEG C after steel rolling, further goes de-stress.
Steel performance index manufactured in the present embodiment reaches Rm 951Mpa, Re 833Mpa, A 21%, Z 64%, KV2 (-
101℃)32J。
Steel prepared by embodiment 1-3 carry out performance measurement, as a result as follows：
Table 1 is the service check result for the 42CrNi2Mo steel that 1-3 of the embodiment of the present invention is obtained
1 mechanical performance index of table
Table 2 is the macroscopic examination result of steel prepared by 1-3 of the embodiment of the present invention.
2 steel macroscopic examination result (grade) of table
| Specification/mm | General Loosen | Center porosity | Pattern segregation | General spot segregation | Edge spot segregation |
| Φ88 | 0/0 | 1.0/1.0 | 0.5/0.5 | Nothing | Nothing |
| Φ95 | 0/0 | 1.0/1.0 | 0.5/0.5 | Nothing | Nothing |
| Φ100 | 0.5/0.5 | 1.0/1.0 | 0/0 | Nothing | Nothing |
| Standard requirement | ≤2.5 | ≤2.5 | ≤2.5 | - | - |
Table 3 is P, S content, field trash and grain size inspection result in steel prepared by invention embodiment 1-3.
3 non-metallic inclusion of table is graded with grain size
It should be appreciated that the purposes of these embodiments is merely to illustrate the present invention and is not intended to limitation protection model of the invention
It encloses.In addition, it should also be understood that, after reading the technical contents of the present invention, those skilled in the art can make the present invention each
Kind change, modification and/or variation, all these equivalent forms equally fall within and are protected defined by the application the appended claims
Within the scope of shield.
Claims (2)
1. a kind of resistance to ultralow temperature impacts wind-powered electricity generation high-strength bolt steel making method, it is characterised in that：Include the following steps：It is multiple to push up bottom
Blow basic bessemer converter just refining, LF refining furnace refining, the degassing of VD vacuum drying ovens, large round billet circular-arc type continuous casting machine continuous casting, steel rolling heating, dephosphorization with
And iron oxide scale, roll, enter to cheat slow cooling, wherein：
The concrete technology of refining is at the beginning of the top and bottom complex blowing basic bessemer converter：Using high-quality molten iron as main material, and it is equipped with pig iron composition refining
Steel primary raw material, liquid iron charging ratio reach 80%, " double slags " method dephosphorization, terminal point control (C+Mn) content are used in converting process
Wt >=0.18%, P content wt≤0.010% of tapping；Add SiCaBaAl 1.0kg/t steel, steel-core-aluminium when 15~20t of tapping
2.0kg/t steel-deoxidizings, iron alloy material, carburant, slag charge are then added in packet, and the tapping later stage uses argon gas strong mixing, with uniform
Temperature and ingredient, and deoxidation products is promoted to float；
The concrete technology of LF refining furnace refining is：Refining furnace calcium carbide early period and silicon carbide diffusive deoxidation are formed white as early as possible
Slag, the dual alkalinity R control of white slag is 4~9%, chemical Composition Control target：C, Si contents wt presses 0.39~0.41%, 0.23
~0.27% lower limit controls；Mn, Cr, Ni, Mo content wt are controlled by 0.78%, 0.83%, 1.73%, 0.23% desired value；S contains
Measure wt≤0.010%；Al content wt：0.030~0.040%；Finishing slag dual alkalinity R2 >=4.0 are refined, the refining finishing slag
Chemical composition wt% is：(FeO+MnO) < 0.60%, CaO 50~65%, SiO25~18%, MgO 0.2~3.0%,
Al2O325~30%, S 0.30~0.60%；
The concrete technology of VD vacuum drying ovens degassing is：Keep 15min with enterprising in the case where 1650 ± 10 DEG C, vacuum degree are less than 67Pa
Row VD Fruit storages, after treatment feed 1.5~2.0m/t CaSi core-spun yarns and carry out denaturation treatment to molten steel, simultaneously
The protection that addition charring rice husk carries out molten steel covers, argon gas 15~30min of soft stirring before bull ladle, 1550 ± 15 DEG C of bull ladle temperature；
The concrete technology of the large round billet circular-arc type continuous casting machine continuous casting is：Big packet long nozzle uses Ar seal apparatus, blows big Baogang's stream
Argon is protected, and the degree of superheat is at 25~40 DEG C, and carbon mould flux during Φ 350mm round billets use, pulling rate is 0.48 ± 0.2m/min, even
Casting machine uses M-EMS parameter 3Hz/250A, and after the infrared Length-fixing cutting of line, high temperature is clamped into hole slow cooling strand；
The concrete technology of steel rolling heating is：Φ 350mm steel billets are controlled using walking beam furnace using preheating section temperature
≤ 800 DEG C, one section of 1100-1180 DEG C of temperature is heated, two sections of temperature controls is heated at 1180-1220 DEG C, heats two sections and soaking
Section soaking time is more than 3 hours, and high temperature section (two sections of one section of heating and heating) total heating time is more than 6 hours heating process；
The concrete technology of the dephosphorization and iron oxide scale is：After the high pressure water dephosphorization of 20-24MPa, used before open rolling
The broken iron oxide scale for bonding fastening of manipulator transverse shifting, the 2nd, 4,6 passage double steel methods reject side scale when roughing；
It is described to enter to cheat the concrete technology of slow cooling and be：Enter to cheat slow cooling mode using 500 DEG C of > after steel rolling.
2. a kind of resistance to ultralow temperature as described in claim 1 impacts wind-powered electricity generation high-strength bolt steel making method, it is characterised in that：Institute
It includes fero-manganesesilicon, ferrochrome, nickel plate and molybdenum-iron to state iron alloy material；Wherein, 2/3 quantity of nickel plate is added in first furnace, and 1/3 quantity exists
It is added in tapping process, and nickel plate carries out 650-750 DEG C of heat preservation, the time is more than 4 hours expansion hydrogen anneal process；The slag charge
Include the mixture of lime, pro-molten refining slag and fluorite.
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| CN107746910A (en) * | 2017-11-12 | 2018-03-02 | 湖南华菱湘潭钢铁有限公司 | A kind of production method of CrNiMo alloys round steel |
| CN108517390A (en) * | 2018-03-28 | 2018-09-11 | 河钢股份有限公司 | Improve the refining slag system and method for refining of VD dehydrogenation efficiency |
| CN108531815A (en) * | 2018-05-24 | 2018-09-14 | 本钢板材股份有限公司 | High temperature bolt steel BG25Cr2MoVA and preparation method thereof |
| CN109097665B (en) * | 2018-09-28 | 2019-12-31 | 邢台钢铁有限责任公司 | Smelting method of high-strength atmospheric corrosion resistant bolt steel |
| CN109402320A (en) * | 2018-11-27 | 2019-03-01 | 南京钢铁股份有限公司 | A kind of preparation method of high cleanliness wind-powered electricity generation fastener |
| CN110899330B (en) * | 2019-10-29 | 2021-09-10 | 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 |
| CN111041325B (en) * | 2019-11-06 | 2021-03-23 | 中天钢铁集团有限公司 | Production method of steel for hand tool |
| CN111321273B (en) * | 2020-03-16 | 2021-06-15 | 马鞍山钢铁股份有限公司 | Method for accurately controlling alkalinity of 42CrMo steel refining slag |
| CN112359274A (en) * | 2020-09-29 | 2021-02-12 | 江苏永钢集团有限公司 | Round steel for high-strength wind power anchor bolt and manufacturing method thereof |
| CN114769544B (en) * | 2020-11-25 | 2024-03-01 | 宝钢德盛不锈钢有限公司 | Production method for reducing mountain scales at hot rolled edge of 200 series stainless steel |
| CN113584390B (en) * | 2021-08-03 | 2022-05-13 | 宝武杰富意特殊钢有限公司 | Round steel for high-strength bolt and preparation method thereof |
| CN114015832A (en) * | 2021-10-26 | 2022-02-08 | 山东寿光巨能特钢有限公司 | Production method of round steel for minus 40 ℃ impact-resistant high-strength bolt |
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