CN106086595A - A kind of it is prevented effectively from the production technology that marine anchor chain round steel cracks - Google Patents

A kind of it is prevented effectively from the production technology that marine anchor chain round steel cracks Download PDF

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CN106086595A
CN106086595A CN201610614669.9A CN201610614669A CN106086595A CN 106086595 A CN106086595 A CN 106086595A CN 201610614669 A CN201610614669 A CN 201610614669A CN 106086595 A CN106086595 A CN 106086595A
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steel
round steel
slag
anchor chain
temperature
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豆乃远
万文华
滕力宏
王日红
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Zenith Steel Group Co Ltd
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Zenith Steel Group Co Ltd
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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
    • 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
    • B22D11/111—Treating the molten metal by using protecting powders
    • 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
    • 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
    • B22D11/12—Accessories for subsequent treating or working cast stock in situ
    • B22D11/1226—Accessories for subsequent treating or working cast stock in situ for straightening strands
    • 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
    • C21C5/52—Manufacture of steel in electric furnaces
    • 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
    • C21C7/0006—Adding metallic additives
    • 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
    • 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
    • C21C7/064—Dephosphorising; Desulfurising
    • 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
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • 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
    • C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
    • 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
    • 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
    • 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
    • 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
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • 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
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
    • 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
    • C22C38/16—Ferrous alloys, e.g. steel alloys containing copper
    • 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
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

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  • Treatment Of Steel In Its Molten State (AREA)

Abstract

The present invention relates to a kind of be prevented effectively from the production technology that marine anchor chain round steel cracks.Preparation method includes electric furnace smelting operation, LF external refining operation, billet continuous casting operation and rolling process step.nullRational designing chemical composition，Control carbon equivalent，Add Ti V-N steel，Control P、S content≤0.015%，Control N content≤70ppm，Conservative control residual elements Cu、The content of Nb etc.，LF carries out sealing，The soft argon blowing rate of conservative control，Prevent molten steel from inhaling nitrogen，Reinforced aluminum deoxidation、The soft argon blowing time of proper extension，Continuous casting uses whole process protection casting，Low pulling rate、Low overheat，Select suitable covering slag，Improve straightening temperature，Continuous casting billet enters to cheat slow cooling，The good tapping interval of roll control，Improve compression ratio，Select rational Technology for Heating Processing，Use the marine anchor chain round steel that the inventive method produces，Operation is simple、With low cost、It is made without application of vacuum，The surface quality of the marine anchor chain round steel existence solving production at present is bad，Crackle occurs that ratio is high、The technical barriers such as quality is unstable.

Description

A kind of it is prevented effectively from the production technology that marine anchor chain round steel cracks
Technical field
The invention belongs to metallurgical technology field, relate in particular to a kind of be prevented effectively from what marine anchor chain round steel cracked Production technology.
Background technology
The 85% of world commerce is transported by boats and ships, and marine anchor chain is can not in naval vessel and ocean engineering The vitals lacked, is the product of a kind of high intensity, high technology content.At present, China is global most important shipbuilding One of country, Diesel engine accounts for more than the 70% of whole nation shipbuilding total amount, along with ocean, river shipping and offshore oil industry Development, anchor steel market potential is relatively big, and development prospect is wide.Industrially developed country's marine anchor chain steel is used mostly tensile strength Three grades of anchor chain steel of 690MPa level, owing to three grades of anchor chain steel are widely used in the mooring location of large ship, oil platform, Residing harsh environmental conditions, therefore it is required that it has the performances such as enough intensity, toughness and good solderabilities.
Owing to anchor chain steel carbon equivalent is higher, Fe content is high, its free linear shrinkage value is more much larger than carbon steel, heat conductivity Little, for the 1/4～1/6 of carbon steel, very sensitive to crackle, if composition design, residual element content and processing parameter etc. Absent measures is improper, is very easy to crack, and especially anchor chain is more prone to longitudinal crack when bending ring, has a strong impact on Safety of ship, and user is after the processes processes such as blanking, sensing heating, bending ring, welding, deburring, it is desirable to obtain good Weldquality, enough intensity, the final products such as good surface quality, it is therefore desirable to raw material has intact surface Quality, high low-temperature flexibility, organize uniformly, it is ensured that material have in chain process processed stable sawing, preheating, brake forming and Welding performance.
If user in use occurs that crackle, whole piece anchor chain may do scraps process, anchor chain manufacturing firm can be given Bring heavy financial burden, greatly reduce the production efficiency of enterprise, if weld impingement value is on the low side, bear at seawater corrosion, height After using a period of time under the conditions of lotus, corrosion, wear phenomenon is serious, and crackle occur in indivedual chain links, can be thrown by client equally Tell, how to obtain and meet properties and the preferable surface quality that user requires, it is to avoid crackle occurs, is domestic anchor steel phase Close the common issue that manufacturer is faced.
Summary of the invention
Present invention aims to above technical barrier, by appropriate design composition, appropriate design technological parameter, control Residual element content processed and control the means such as gas content, it is provided that a kind of be prevented effectively from the life that marine anchor chain round steel cracks Production. art, operation is simple, with low cost, be made without application of vacuum, just can while meeting user's properties requirement, The surface quality of to crack sensitivity strong marine anchor chain round steel is effectively ensured, it is to avoid crack, fully meet domestic and international ship Demand with anchor chain round steel client.
To achieve these goals, the invention provides and a kind of be prevented effectively from the production work that marine anchor chain round steel cracks Skill, including electric furnace smelting operation, LF refining procedure, billet continuous casting operation and rolling process, concrete operations are as follows:
(1) electric furnace smelting uses high-quality molten iron and cleaning steel scrap, omnidistance BOTTOM ARGON BLOWING, designing chemical composition, controls carbon equivalent, Add Ti V-N steel, control P, S content≤0.015%, control the content of residual elements Cu, Nb, control tapping terminal feelings Condition, tapping process uses pushing off the slag operation, forbids slag to tap, and deoxidizer addition is: carborundum 100kg, aluminium block addition root Add according to tapping carbon；
As preferably, step (1) described high-quality molten iron, it is desirable to [Si]: 0.30～0.70%, [P]≤0.12%, [S]≤ 0.030%, temperature T >=1300 DEG C, content≤0.15% of described control residual elements Cu, content≤0.05% of Nb；
Phosphorus is harmful element, serious segregation easily occurs on the column crystal boundary of solidification, increases crackle tendency, the easy shape of sulfur Become red brittleness eutectic, and separate out at grain boundaries, easily at grain boundaries generation crackle, accordingly, it would be desirable to the phosphorus controlled in steel, sulfur contain Amount；There is data to show, in steel during residual elements copper content ＞ 0.15%, the steel plasticity when hot-working can be reduced, accelerate crackle Generation and development, Nb easily forms Nb (C, N) in steel, causes embrittlement of grain boundaries, makes to be formed in the later strand of solidification crackle；
As preferably, step (1) is described controls tapping terminal situation, taps [C]: 0.07～0.18%, and tapping [P]≤ 0.012%, tapping temperature: 1625～1665 DEG C；Aluminium block addition adds according to tapping carbon, and tapping carbon ＞ 0.12% adds aluminum 90kg, tapping carbon ＜ 0.08% add aluminum 140kg, and other adds aluminum 120kg；
Add different aluminium blocks according to molten steel oxidation degree difference during tapping and carry out pre-deoxidation, be greatly improved the profit of aluminium block By rate, and it is bad or produce too much field trash to avoid pre-deoxidation；
As preferably, step (1) described appropriate design composition [C]: 0.28～0.32%, [Mn]: 1.45～1.60%, [Cr]: 0.15～0.25%, [Al]: 0.025～0.055%, [Ti]: 0.010～0.025%；Control carbon equivalent Ceq≤ 0.65；
Carbon equivalent can increase the sensitivity of crackle, by adding a certain amount of Cr in steel, improves the heart of big specification steel Portion's mechanical performance, adds titanium and carries out microalloying, while properties can be made to meet requirement, reduces carbon equivalent, meanwhile, adds titanium Can prevent steel surface from cracking with fixed nitrogen；
(2) LF refining furnace good seal, it is ensured that Deoxidation Atmosphere in Furnace, prevent molten steel exposed, inhale nitrogen；Reinforced aluminum deoxidation, Power transmission is fed aluminum steel and is adjusted aluminum to 0.040%～0.050% after 5 minutes；Prometaphase uses the strengthening deoxidation of carborundum, aluminum shot and desulfurization behaviour Make, it is ensured that white slag time >=25 minute；Guarantee the mobility of refining slag, control refining slag basicity R >=3.5；Before bull ladle 3～5 points Clock adds ferrotianium 0.60～0.65kg/t or feeding titanium wire 1.5～1.6m/t, feeds pure calcium line 0.8～1.5m/t and carry out before bull ladle Final deoxidizing and inclusion modification, extend soft argon blowing time, controls soft argon blowing rate, connects and waters heat bull ladle temperature: 1555 after soft blow ～1570 DEG C, titanium is the element easily aoxidized, and the addition of titanium directly affects the absorbance of titanium and the effect in steel opportunity, and In casting cycle, titaniferous molten steel is easily at nozzle clogging, mainly with the steel of solidification as matrix, and enriched titaniferous and the oxidation of aluminum Thing, therefore, should control reasonably to add titanium amount and addition opportunity, it is to avoid terminal molten steel peroxidating.
A nozzle clogging difficult problem in the case of using Calcium treatment technology to solve aluminum height, reduces inclusion content of steel, carries The degree of purity of Gao Gang.MnS field trash in steel is transformed into CaS simultaneously, reduces because MnS is mingled with the anisotropy making steel produce.
As preferably, described in step (2), prevent that molten steel is exposed, inhale nitrogen, it is desirable to nitrogen content≤70ppm；
As preferably, described in step (2), extend soft argon blowing time, soft argon blowing time by within 15～20 minutes, be optimized for 20～ 25 minutes；Described soft argon blowing rate 70～90NL/min；
Carrying out soft blow argon process after alloying, the proper extension soft blow time, to realize having the enough calm time to promote folder Foreign material float, and reduce inclusion content of steel, are finally reached the purpose purifying steel；
(3) continuous casting uses whole process protection casting, middle bag to use Integral nozzle, and middle bag baking temperature reaches more than 1000 DEG C；Open Before watering, the middle first argon filling of bag, big bag argon seals, then opens and water, and Kai Jiaohouzhong Baogang liquid level exceedes slag blocking wall and most goes up hole and can add middle bag Coverture, after middle covering agent covers, can stop tundish argon filling；Add middle covering agent in time, forbid that molten steel occurs Exposed；Metal in Tundish is kept to pour into a mould in high level；Keep crystallizer molten steel surface stable, fluctuating margin in the range of ± 2.5mm, Employing automatic casting control, prevent because of casting billet surface slag inclusion cause round steel face crack or stick up skin, lose flesh defect；It is low overheated to use The cast of degree, low pulling rate, the degree of superheat controls at 20～35 DEG C, pulling rate 0.85～0.95m/min, prevents steel from producing shrinkage cavity and implosion Defect；The two weak cold water distribution patterns of cold employing, specific water is 0.22L/Kg, with M-EMS, and uses crystallizer to protect Slag, covering slag spares no effort to, adds less, keeps black flour operation and drag for slag in time and remove the resistance to material in the mouth of a river of fusing；Improve straightening temperature,
Use the casting of low overheat, low pulling rate and drag for slag technique in time, striving for for promoting field trash to float in a crystallizer The more time, increase the probability that field trash is adsorbed by covering slag, and dragged for protection slag strip in time, it is to avoid because of lubrication not The good crackle caused；
In step (3), described crystallizer protecting residue is western precious special anchor steel covering slag, wherein basicity be R=0.85～ 0.95, fusing point 1070～1100 DEG C, viscosity is 0.45～0.55Pa.S/1300 DEG C, and C is 13.0～14.0% admittedly；Every 2 hours Measure a liquid slag layer thickness, it is ensured that the liquid slag layer degree of depth is 6～9mm；Crystallizer one cold water flow is 111m3/ h, it is ensured that one is cold Water temperature difference 7～8 DEG C；Middle water-coating port diameter of phi 40mm, mouth of a river insertion depth is 90～110mm, and M-EMS is 180A/ 2Hz (improves M-EMS Current, it is possible to decrease the thickness of initial solidification shell, reduce depth of chatter mark)；Vibration parameters: amplitude (mm)±2.5；Frequency (opm) 130+60V (properly increases frequency of vibration, reduces the negative slip time)；
In step (3), described raising straightening temperature, temperature 1000 DEG C～1050 DEG C before aligning, upper surface and the side temperature difference ≤20℃；
Production practices finding, suitable raising is entered straightening temperature and is conducive to improving continuous casting billet quality, it is to avoid crack, Therefore, temperature before aligning is changed into 1000 DEG C～1050 DEG C by 980 DEG C～1030 DEG C；
Continuous casting billet uses transition cold bed high temperature ejection, and " one " font is added a cover hole and uncapped after cold 48 hours, and temperature≤140 DEG C turn Fortune, middle bag casting cycle is not more than 15 hours；When casting short interruption, double teeming base is hung out process；Middle bag stops watering tail base Process, it is to be ensured that strand zero defect；The low liquid level of middle bag waters strand and other waters injection extremely, will individually pick out stacking,
" one " font is used to add a cover into hole slow cooling, [H] content can being substantially reduced in steel, it is to avoid stocking occurs that white point is existing As, in employing, bag casting cycle is not more than 15 hours, and crystallizer protecting residue can be avoided to crust in a large number, seriously hinders the equal of melt cinder Uniform flow enters thus the inhomogeneous cooling of green shell can be caused even, causes continuous casting billet surface to crack；
(4) steel rolling is strengthened cooling controlling and rolling controlling process and is controlled, and controls tapping interval well, improves compression ratio, and stocking enters cheats slow cooling, choosing Use rational Technology for Heating Processing, hardening heat: 900 ± 15 DEG C；Temperature: 600 ± 30 DEG C.In step (4), described steel rolling adds Strong cooling controlling and rolling controlling process controls, Soaking Pit Temperature 1190～1220 DEG C, start rolling temperature 1100～1130 DEG C, total heat time heating time 170 ～210min, enter stove rhythm 120～150 seconds/, having rolled rear round steel should slow cooling in time, it is ensured that round steel enters hole and adds a cover slow cooling Time cannot be less than 24 hours；
Tapping interval is controlled in employing well, improves compression ratio, can improve the surface quality of stocking, strengthens that continuous casting billet is tiny to be split The seam ability of stricture of vagina；
It is improper that Technology for Heating Processing controls, and also can accelerate the extension of crackle, make crackle from outward appearance to inner essence, by short and long, affects anchor The quality of chain；
The beneficial effects of the present invention is:
By rational designing chemical composition, control carbon equivalent, control residual element content, selection suitable procedures, rationally set The meter means such as technological parameter and strict implement normalizing operation, there is surface quality in the marine anchor chain round steel solving production at present The technical barriers such as bad, crackle ratio is high, weldquality is bad, quality is unstable.
The present invention improves the intensity of steel by improving the content of element silicon, on the premise of performance meets requirement, reduces manganese The content of element, meanwhile, adds certain chromium element, reduces the content of easy segregation P element, strict control nitrogen element as far as possible Content, reduces the carbon equivalent causing crack-sensitivity characteristic, avoids because P segregation, nitrogen content too high precipitation aluminium nitride are led simultaneously The face crack caused, plays the effect that Crack prevention produces；By taking continuous casting billet and stocking retarded cooling process to replace vacuum refining Technique serves avoids the too high effect causing steel hydrogen embrittlement and stress cracking occur of hydrogen content in invar, avoids because of true simultaneously Empty refining process occurs continuous casting billet surface defect that vacuum slag phenomenon causes and vacuum fine aluminium metallurgy damage excessive cause subcutaneous It is mingled with the risk of the Cracks In Continuous Cast Billets caused.
Operation of the present invention is simple, with low cost, can be while meeting user's properties requirement, it is possible to it is right to be effectively ensured The surface quality of the marine anchor chain round steel that crack sensitivity is strong, it is to avoid crack, produces and fully meets marine anchor chain round steel The anchor chain round steel that the usability of user requires.
Detailed description of the invention
Production technology is summarized as follows:
Electric furnace smelting → LF ladle refining → billet continuous casting (220*260mm2) → mill milling.
Embodiment 1 (heat (batch) number 616030121)
(1) electric furnace smelting operation
Electric furnace smelting uses high-quality molten iron and cleaning steel scrap, omnidistance BOTTOM ARGON BLOWING, wherein, enters constituent mass in stove molten iron and contains Amount: Si:0.49%, P:0.093%, S:0.021%, enters stove molten iron temperature T=1308 DEG C；The content of control residual elements Cu≤ Content≤0.05% of 0.15%, Nb
Appropriate design composition: [C]: 0.28～0.32%, [Mn]: 1.45～1.60%, [Cr]: 0.15～0.25%, [Al]: 0.025～0.055%, [Ti]: 0.010～0.025%；Control carbon equivalent Ceq≤0.65；Electric furnace smelting controls tapping Terminal tapping [C]: 0.11%, taps [P]: 0.010%, tapping temperature: 1635 DEG C, and tapping process uses pushing off the slag operation, forbids Slag is tapped, and deoxidizer addition is: carborundum 100kg, aluminium block 120kg；
(2) LF refining procedure
LF refining furnace good seal, it is ensured that Deoxidation Atmosphere in Furnace, prevent molten steel exposed, inhale nitrogen, nitrogen content 51ppm；By force Changing aluminium deoxidation, power transmission is fed aluminum steel and is adjusted aluminum to 0.045% after 5 minutes；Prometaphase uses the strengthening deoxidation of carborundum, aluminum shot and desulfurization behaviour Make, it is ensured that 30 minutes white slag time；Guarantee the mobility of refining slag, control refining slag basicity R=4.2；Bull ladle adds for first 4 minutes Ferrotianium 0.63kg/t, feeds pure calcium line 1.0m/t and carries out final deoxidizing and inclusion modification, extend soft argon blowing time, soft blow before bull ladle 22 minutes argon time；Described soft argon blowing rate 80NL/min, connects after soft blow and waters heat bull ladle temperature: 1565 DEG C；
(3) continuous casting working procedure
Continuous casting uses whole process protection casting, middle bag to use Integral nozzle, and middle bag baking temperature reaches 1085 DEG C；Open before watering, in The first argon filling of bag, big bag argon seals, then opens and water, and Kai Jiaohouzhong Baogang liquid level exceedes slag blocking wall and most goes up hole and can add middle covering agent, After middle covering agent covers, tundish argon filling can be stopped；Add middle covering agent in time, forbid occur that molten steel is exposed；Protect Hold Metal in Tundish to pour into a mould in high level；Keeping crystallizer molten steel surface stable, fluctuating margin, in the range of ± 2mm, uses automatically Cast control, prevent because of casting billet surface slag inclusion cause round steel face crack or stick up skin, lose flesh defect；Use low overheat, low draw Speed cast, the degree of superheat controls at 30 DEG C, pulling rate 0.90m/min, prevents steel from producing shrinkage cavity and implosion defect；Two cold employings are weak cold Water distribution pattern, specific water is 0.22L/Kg, with M-EMS, and use crystallizer protecting residue, covering slag to spare no effort to, few Add, keep black flour operation and drag for slag in time and remove the resistance to material in the mouth of a river of fusing；Improve straightening temperature, the front temperature 1025 DEG C of aligning, Upper surface and the side temperature difference 10 DEG C；
In step (3), described crystallizer protecting residue is western precious special anchor steel covering slag, and wherein basicity is R=0.90, molten Point 1082 DEG C, viscosity is 0.50Pa.S/1300 DEG C, and C is 13.75% admittedly；A liquid slag layer thickness is measured every 2 hours, it is ensured that The liquid slag layer degree of depth is 7～8mm；Crystallizer one cold water flow is 111m3/ h, it is ensured that a cold water temperature difference 7～8 DEG C；Middle water-coating port is straight Footpath Φ 40mm, mouth of a river insertion depth is 90～100mm, and M-EMS is 180A/2Hz；Vibration parameters: amplitude (mm) ± 2.5；Frequency (opm) 130+60V；
Continuous casting billet uses transition cold bed high temperature ejection, and " one " font is added a cover and within 48 hours, uncapped into hole slow cooling, and temperature 130 DEG C turns Fortune, middle bag casting cycle 14 hours；Extremely watering injection individually picks out stacking,
(4) rolling process
Steel rolling is strengthened cooling controlling and rolling controlling process and is controlled, and controls tapping interval well, improves compression ratio, and stocking enters cheats slow cooling, soaking Furnace temperature 1199 DEG C, start rolling temperature 1113 DEG C, total heat time heating time 190min, enter stove rhythm 130 seconds/, rolled rear round steel Should slow cooling in time, it is ensured that round steel enters hole and adds a cover the slow cooling time 25 hours, selects rational Technology for Heating Processing, hardening heat: 900 ℃；Temperature: 600 DEG C.
Continuous casting billet surface, stocking surface and user use rear surface quality good, and crackle does not all occur.
Embodiment 2 (heat (batch) number 616030122)
Electric furnace smelting controls tapping terminal [P]=0.009%, steel [C]=0.14% eventually, and tapping adds aluminum 90kg, remaining
Operate same as in Example 1.
Embodiment 3 (heat (batch) number 616030123)
Ensure 28 minutes white slag time；Guarantee the mobility of refining slag, control refining slag basicity R=4.3, remaining operation with Embodiment 1 is identical.
The chemical composition of steel obtained by embodiment 1-3, mechanical property, surface quality situation are shown in Table 1, table 2 and table 3 institute respectively Show:
The chemical composition (wt/%) of the steel prepared by table 1 example 1-3
Table 2 mechanical property (test carried out for the steel prepared by example 1-3)
Heat (batch) number Yield strength Re Tensile strength Rm Elongation percentage A (%) Contraction percentage of area Z (%) Ballistic work AKV (J)
616030121 608 779 23.5 69 151
616030122 610 778 23.0 70 153
616030123 605 772 23.5 68 149
Table 3 anchor steel surface quality (prepares, for example 1-3, the test that steel is carried out)
Heat (batch) number Surface quality of continuously cast slab Stocking surface quality Heat treatment rear surface quality condition
616030121 Intact, flawless Intact, flawless Intact, flawless
616030122 Intact, flawless Intact, flawless Intact, flawless
616030123 Intact, flawless Intact, flawless Intact, flawless
Comparative example 1
" nitrogen content 51ppm " in example 1 step (1) is revised as " nitrogen content 72ppm ", and other conditions are with embodiment 1.
Testing the final round steel prepared, round steel surface quality is bad, many places elongated crack occurs, much worse than this The surface quality of the steel of preparation in bright embodiment.
Comparative example 2
" 30 minutes white slag time of guarantee " in example 1 step (2) is revised as " ensure 20 minutes white slag time, other Part is with embodiment 1.
Testing the final round steel prepared, round steel surface quality is bad, many places elongated crack occurs, much worse than this The surface quality of the steel of preparation in bright embodiment.
Comparative example 3
" appropriate design composition: [Mn]: 1.45～1.60% " in example 1 step (1) is revised as [Mn]: 1.70～ 1.85% ", other conditions are with embodiment 1.Testing the final round steel prepared, round steel surface quality is not ideal, goes out Existing many places longitudinal crack, much worse than the surface quality of the steel of preparation in the embodiment of the present invention.
Comparative example 4
" continuous casting billet uses transition cold bed high temperature ejection, and " one " font adds a cover hole cold 48 hours " in example 1 step (3) is repaiied Changing " continuous casting billet uses transition cold bed high temperature ejection, and heap is cold " into, other conditions are with embodiment 1.
Testing the final round steel prepared, round steel surface quality is bad, and hair check is more, implements much worse than the present invention The surface quality of the steel of preparation in example.
Comparative example 5
" after rolling completes, round steel should slow cooling in time " in example 1 step (4) is revised as that " after rolling completes, round steel should be timely Heap is cold ", other conditions are with embodiment 1.
Testing the final round steel prepared, round steel surface quality is bad, many places hair check occurs, much worse than the present invention The surface quality of the steel of preparation in embodiment.
Comparative example 6
" enter to cheat slow cooling " by example 1 step (3) and in step (4), " slow cooling " is revised as " heap is cold ", " and LF refining procedure knot Vacuum refining operation is proceeded to after bundle ", other conditions are with embodiment 1.
Testing the final round steel prepared, there is many places elongated crack in round steel surface, much worse than the embodiment of the present invention The surface quality of the steel of middle preparation.

Claims (9)

1. one kind is prevented effectively from the production technology that marine anchor chain round steel cracks, it is characterised in that: described production technology bag Including electric furnace smelting operation, LF external refining operation, billet continuous casting operation and rolling process, concrete operations are as follows:
(1) electric furnace smelting operation
Electric furnace smelting raw material uses high-quality molten iron and cleaning steel scrap, omnidistance BOTTOM ARGON BLOWING, designing chemical composition, controls carbon equivalent, adds Add Ti V-N steel, control P, S content≤0.015%, control the content of residual elements Cu, Nb, control tapping terminal situation, Tapping process uses pushing off the slag operation, forbids slag to tap, and deoxidizer addition is: carborundum 100kg, and aluminium block addition is according to going out Steel carbon adds；
(2) LF refining procedure
LF refining furnace good seal, it is ensured that Deoxidation Atmosphere in Furnace, prevent molten steel exposed, inhale nitrogen；Reinforced aluminum deoxidation, power transmission 5 points Feeding aluminum steel after clock adjusts aluminum to 0.040%～0.050%；Prometaphase uses the strengthening deoxidation of carborundum, aluminum shot and desulfurization, and the later stage uses Carborundum carries out slag interface deoxidation, it is ensured that white slag time >=25 minute；Guarantee the mobility of refining slag, control refining slag basicity R≥3.5；Within before bull ladle 3～5 minutes, add ferrotianium 0.60～0.65kg/t or feeding titanium wire 1.5～1.6m/t, feed pure before bull ladle Calcium line 0.8～1.5m/t carries out final deoxidizing and inclusion modification, extends soft argon blowing time, controls soft argon blowing rate, connects after soft blow Water heat bull ladle temperature: 1555～1570 DEG C；
(3) billet continuous casting operation
Continuous casting uses whole process protection casting, middle bag to use Integral nozzle, and middle bag baking temperature reaches more than 1000 DEG C；Open before watering, in The first argon filling of bag, big bag argon seals, then opens and water, and Kai Jiaohouzhong Baogang liquid level exceedes slag blocking wall and most goes up hole and can add middle covering agent, After middle covering agent covers, tundish argon filling can be stopped；Add middle covering agent in time, forbid occur that molten steel is exposed；Protect Hold Metal in Tundish to pour into a mould in high level；Keep crystallizer molten steel surface stable, fluctuating margin in the range of ± 2.5mm, use from Dynamic cast controls, prevent because of casting billet surface slag inclusion cause round steel face crack or stick up skin, lose flesh defect；Use low overheat, low Pulling rate is poured into a mould, and the degree of superheat controls at 20～35 DEG C, pulling rate 0.85～0.95m/min, prevents steel from producing shrinkage cavity and implosion defect； The two weak cold water distribution patterns of cold employing, specific water is 0.22L/Kg, with M-EMS, and uses crystallizer protecting residue, protects Protect slag to spare no effort to, add less, keep black flour operation and drag for slag in time and remove the resistance to material in the mouth of a river of fusing；Improve straightening temperature；
Continuous casting billet uses transition cold bed high temperature ejection, and " one " font is uncapped after adding a cover hole slow cooling 48 hours, and temperature≤140 DEG C turn Fortune, middle bag casting cycle is not more than 15 hours；When casting short interruption, double teeming base is hung out process；Middle bag stops watering tail base Process, it is to be ensured that strand zero defect；The low liquid level of middle bag waters strand and other waters strand extremely, will individually pick out stacking；
(4) rolling process
Steel rolling is strengthened cooling controlling and rolling controlling process and is controlled, and controls tapping interval well, improves compression ratio stocking, enters and cheat slow cooling, selects rationally Technology for Heating Processing.
A kind of it is prevented effectively from the production technology that marine anchor chain round steel cracks, it is characterised in that: High-quality molten iron described in step (1), it is desirable to [Si]: 0.30～0.70%, [P]≤0.12%, [S]≤0.030%, temperature T >= 1300 DEG C, content≤0.15% of described control residual elements Cu, content≤0.05% of Nb.
A kind of it is prevented effectively from the production technology that marine anchor chain round steel cracks, it is characterised in that: Control tapping terminal situation described in step (1), tap [C]: 0.07～0.18%, [P]≤0.012% of tapping, tapping temperature: 1625～1665 DEG C；Aluminium block addition adds according to tapping carbon, and tapping carbon ＞ 0.12% adds aluminum 90kg, tapping carbon ＜ 0.08% and adds Aluminum 140kg, other adds aluminum 120kg；Described designing chemical composition: [C]: 0.28～0.32%, [Mn]: 1.45～1.60%, [Cr]: 0.15～0.25%, [Al]: 0.025～0.055%, [Ti]: 0.010～0.025%；Control carbon equivalent Ceq≤ 0.65, control N content≤70ppm.
A kind of it is prevented effectively from the production technology that marine anchor chain round steel cracks, it is characterised in that: Prevent described in step (2) molten steel exposed, inhale nitrogen, it is desirable to nitrogen content≤70ppm.
A kind of it is prevented effectively from the production technology that marine anchor chain round steel cracks, it is characterised in that: Extending soft argon blowing time described in step (2), soft argon blowing time is 20～25 minutes；Described soft argon blowing rate 70～90NL/ min。
A kind of it is prevented effectively from the production technology that marine anchor chain round steel cracks, it is characterised in that: In step (3), described crystallizer protecting residue is western precious special anchor steel covering slag, and wherein basicity is R=0.85～0.95, fusing point 1070～1100 DEG C, viscosity is 0.45～0.55Pa.S/1300 DEG C, and C is 13.0～14.0% admittedly；Measured once every 2 hours Liquid slag layer thickness, it is ensured that the liquid slag layer degree of depth is 6～9mm；Crystallizer one cold water flow is 111m3/ h, it is ensured that a cold water temperature difference 7～ 8℃；Middle water-coating port diameter of phi 40mm, mouth of a river insertion depth is 90～110mm, and M-EMS Current is 180A/2Hz； Vibration parameters: amplitude (mm) ± 2.5；Frequency (opm) 130+60V.
A kind of it is prevented effectively from the production technology that marine anchor chain round steel cracks, it is characterised in that: In step (3), described raising straightening temperature, the front temperature 1000 of aligning～1050 DEG C, upper surface and the temperature difference≤20 DEG C, side.
A kind of it is prevented effectively from the production technology that marine anchor chain round steel cracks, it is characterised in that: In step (4), described steel rolling strengthen cooling controlling and rolling controlling process control, Soaking Pit Temperature 1190～1220 DEG C, start rolling temperature 1100～ 1130 DEG C, total heat time heating time 170～210min, enter stove rhythm 120～150 seconds/, rolled rear round steel should slow cooling in time, Guarantee that round steel enters hole and adds a cover the slow cooling time and cannot be less than 24 hours.
A kind of it is prevented effectively from the production technology that marine anchor chain round steel cracks, it is characterised in that: In step (4), the rational Technology for Heating Processing of described selection is, hardening heat: 900 ± 15 DEG C；Temperature: 600 ± 30 DEG C.
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CN107299278A (en) * 2017-06-01 2017-10-27 山东寿光巨能特钢有限公司 A kind of resistance to ultralow temperature impact wind-powered electricity generation high-strength bolt steel making method
CN109234645A (en) * 2018-09-30 2019-01-18 镇江宝海船舶五金有限公司 A kind of composite material and preparation method thereof applied in marine anchor chain
CN111347022A (en) * 2018-12-24 2020-06-30 新疆八一钢铁股份有限公司 Control method for improving qualified rate of 30CrMoA hot upsetting of sucker rod steel
CN110064742A (en) * 2019-06-10 2019-07-30 成渝钒钛科技有限公司 Continuous cast crystallizer number deepens research method in two steel-making of one kind
CN111996466A (en) * 2020-09-18 2020-11-27 莱芜钢铁集团银山型钢有限公司 V-N microalloyed steel and production method of V-N microalloyed continuous casting billet without surface cracks
WO2022099680A1 (en) * 2020-11-16 2022-05-19 何满潮 Converter and continuously-cast small billet-based production method for npr rock bolt or anchor cable novel material
CN114769545A (en) * 2020-11-25 2022-07-22 宝钢德盛不锈钢有限公司 Production method for reducing mountain scales on hot-rolled edge of 200-series stainless steel
CN114769545B (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
CN113857448A (en) * 2021-11-29 2021-12-31 东北大学 Low-alkalinity coating-free protective slag for continuous casting of hot forming steel
CN113857448B (en) * 2021-11-29 2022-02-22 东北大学 Low-alkalinity coating-free protective slag for continuous casting of hot forming steel

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