CN113751683A - Method for improving internal quality of SWRH82B billet - Google Patents
Method for improving internal quality of SWRH82B billet Download PDFInfo
- Publication number
- CN113751683A CN113751683A CN202111049608.XA CN202111049608A CN113751683A CN 113751683 A CN113751683 A CN 113751683A CN 202111049608 A CN202111049608 A CN 202111049608A CN 113751683 A CN113751683 A CN 113751683A
- Authority
- CN
- China
- Prior art keywords
- swrh82b
- billet
- internal quality
- liquid core
- improving
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 39
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 24
- 239000007788 liquid Substances 0.000 claims abstract description 20
- 238000001816 cooling Methods 0.000 claims abstract description 18
- 238000010438 heat treatment Methods 0.000 claims abstract description 17
- 230000010355 oscillation Effects 0.000 claims abstract description 16
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 11
- 239000010959 steel Substances 0.000 claims abstract description 11
- 238000009749 continuous casting Methods 0.000 claims abstract description 9
- 239000003345 natural gas Substances 0.000 claims abstract description 7
- 238000005204 segregation Methods 0.000 claims description 20
- 238000003756 stirring Methods 0.000 claims description 16
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 11
- 229910052799 carbon Inorganic materials 0.000 claims description 11
- 239000013078 crystal Substances 0.000 claims description 9
- 238000005507 spraying Methods 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 abstract description 6
- 238000009434 installation Methods 0.000 abstract description 5
- 239000007921 spray Substances 0.000 abstract description 2
- 238000005266 casting Methods 0.000 description 16
- 238000005516 engineering process Methods 0.000 description 7
- 238000005096 rolling process Methods 0.000 description 3
- 238000007711 solidification Methods 0.000 description 3
- 230000008023 solidification Effects 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910000734 martensite Inorganic materials 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000010899 nucleation Methods 0.000 description 2
- 230000006911 nucleation Effects 0.000 description 2
- 229910000677 High-carbon steel Inorganic materials 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
Classifications
-
- 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
-
- 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
- B22D11/122—Accessories for subsequent treating or working cast stock in situ 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
- B22D11/16—Controlling or regulating processes or operations
- B22D11/22—Controlling or regulating processes or operations for cooling cast stock or mould
- B22D11/225—Controlling or regulating processes or operations for cooling cast stock or mould for secondary cooling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
- B22D41/50—Pouring-nozzles
- B22D41/60—Pouring-nozzles with heating or cooling means
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Continuous Casting (AREA)
Abstract
The invention relates to the field of continuous casting and manufacturing of small square billets, in particular to a method for improving the internal quality of SWRH82B small square billets. The method comprises the following steps: when producing SWRH82B steel billets, the size and position of a liquid core are controlled by adopting a continuous casting ultrahigh pulling speed and an ultrahigh water ratio process, the pulling speed is controlled to be 3.15-3.60 m/min, and a secondary cooling process is full water spray cooling, and the water ratio is 1.6-2.0L/kg; installing liquid core pulse magnetic oscillation equipment, wherein the installation position of the electromagnetic pulse is 200-; the water gap of the tundish is heated by natural gas, the heating temperature is 1320-. The overall quality of the pre-stressing steel SWRH82B billet can be significantly improved.
Description
Technical Field
The invention relates to the field of continuous casting and manufacturing of small square billets, in particular to a method for improving the internal quality of SWRH82B small square billets.
Background
The SWRH82B steel is a main material for manufacturing prestressed steel strands, and the drawing performance of a wire rod is directly influenced by the internal quality of a casting blank. If the internal quality of a casting blank is poor and the central carbon segregation is serious, reticular carbide can appear in the subsequent rolling process of the wire rod, if the central Cr segregation is serious, a martensite abnormal structure can appear in the subsequent rolling process, and if larger-level looseness, shrinkage cavities or cracks exist in the casting blank, the internal elements of the casting blank are unevenly distributed, so that the abnormal structure appears in the rolling process. Both the network carbides and the martensite have a very adverse effect on the drawing of the wire rod. Meanwhile, in most of the prior processes for producing SWRH82B, the pulling speed is less than or equal to 3.0m/min and is about 2.0m/min to a great extent, which seriously restricts the exertion of the production capacity of a continuous casting machine.
Therefore, how to design a more scientific and efficient method for improving the internal quality of the SWRH82B billet is a problem to be solved by the invention.
Disclosure of Invention
The invention provides a method for improving the internal quality of SWRH82B billet aiming at the defects. The method and the steps of adopting the continuous casting ultrahigh pulling speed and ultrahigh specific water process to control the size and the position of the liquid core, optimizing the casting blank liquid core pulse magnetic oscillation process to improve the isometric crystal area proportion of the casting blank, optimizing the electromagnetic stirring technology to reduce the center segregation index, optimizing the tundish nozzle heating process to reduce the superheat degree and the like are adopted, the internal quality of the prestressed steel SWRH82B billet is obviously improved, and the benefit is created.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a method for improving the internal quality of SWRH82B billet comprises the following steps:
s1, when producing SWRH82B steel billet, adopting the continuous casting ultrahigh pulling speed and superstrong specific water process to control the size and position of the liquid core, which specifically comprises the following steps: the pulling speed is controlled to be 3.15-3.60 m/min, the secondary cooling process is full water spraying cooling, and the specific water amount is 1.6-2.0L/kg; the production efficiency can be obviously improved by the ultrahigh pulling speed (the pulling speed is more than or equal to 3.15m/min), and the solidification and nucleation can be promoted and the central segregation degree of the casting blank can be reduced by matching with the full water-cooling secondary cooling with large specific water amount.
S2, installing liquid core pulse magnetic oscillation equipment, setting the electromagnetic pulse distance to 200-600mm away from the outlet of the crystallizer, and setting the pulse magnetic oscillation process parameter as current of 500-600A; the pulse electromagnetic oscillation process can increase the nucleation point of the initial solidification of the casting blank, the pulse position is 200-600mm, and the internal quality and the surface quality of the casting blank can be improved by matching with the proper current parameter of 500-600A.
S3, setting the specific parameters of terminal electromagnetic stirring as current: 305-345A, frequency: 14-16 Hz; the proper stirring current and the higher stirring frequency can improve the efficiency of the casting blank during solidification and reduce the segregation degree of the casting blank.
S4, heating the tundish nozzle by natural gas at 1320-1400 ℃ and 13-18 ℃ superheat degree. The water gap is heated to more than 1320 ℃, so that low-superheat-degree casting can be realized, low-superheat-degree casting at 13-18 ℃ is realized, the continuous casting speed is improved, the production efficiency is improved, and the internal density and uniformity of a casting blank are improved.
Furthermore, the central shrinkage cavity of the produced SWRH82B billet is 0 grade, the central carbon segregation is 0.99-1.04 grade, and the central porosity is 0-0.5 grade. The central porosity and shrinkage cavity level are high, the central carbon segregation of the small square billet can be high, the central carbon segregation can reach more than 1.15, and the central carbon segregation of the small square billet can be obviously reduced by controlling the central shrinkage cavity and the porosity.
Further, the size of the liquid core of S1 is 50-55 mm for the billet. When the size of the liquid core is 50-55 mm, the electromagnetic stirring has the best stirring effect, the central carbon segregation index of high-carbon steel can be obviously reduced, and the internal quality of the SWRH82B billet is improved.
Furthermore, the equiaxed crystal proportion of S2 is more than or equal to 55 percent. The higher the isometric crystal rate is, the better the density and uniformity of the casting blank is, and the higher the internal quality of the casting blank is.
The invention has the beneficial effects that:
the invention provides a method for improving the internal quality of an SWRH82B small square billet, which can integrally improve the internal quality of the small square billet by adopting a method of controlling the size and the position of a liquid core by adopting a super-strong specific water process, using full water cooling by a secondary cooling process, drawing speed being more than 3.0m/min, simultaneously using water gap heating to reduce superheat degree, adopting a pulse magnetic oscillation technology, reducing the central segregation index by an isometric crystal proportion being more than or equal to 55 percent and adopting an electromagnetic stirring technology and the like.
The specific implementation mode is as follows:
in order to make those skilled in the art better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
A method for improving the internal quality of SWRH82B billet comprises the following steps:
s1, producing an SWRH82B steel billet by adopting a 150-square small square billet, controlling the continuous casting ultrahigh pulling speed to be 3.15m/min, and adopting full water spray cooling in a secondary cooling process, wherein the specific water amount is 1.6L/kg;
s2, installing liquid core pulse magnetic oscillation equipment, setting the electromagnetic pulse installation position to be 200mm away from the outlet of the crystallizer, and setting the pulse magnetic oscillation process parameter to be 500A;
s3, optimizing the electromagnetic stirring technology to reduce the center segregation index, and setting specific parameters of the end electromagnetic stirring as current: 305A, frequency: 14 Hz;
s4, optimizing the tundish nozzle heating process to reduce the superheat degree: the heating mode of the tundish nozzle is natural gas, the heating temperature is 1320 ℃, and the superheat degree is 15 ℃.
The central shrinkage cavity of the produced SWRH82B billet is 0 grade, the central carbon segregation is 0.99 grade, the central porosity is 0.5 grade, the size of the liquid core is 50mm, and the isometric crystal proportion is 55 percent.
Example 2
S1, producing an SWRH82B steel billet by adopting a 150-square small square billet, controlling the ultrahigh pulling speed to be 3.3m/min, and cooling by adopting full water spraying in a secondary cooling process, wherein the specific water amount is 1.8L/k;
s2, installing liquid core pulse magnetic oscillation equipment, setting the electromagnetic pulse installation position to be 400mm away from the outlet of the crystallizer, and setting the pulse magnetic oscillation process parameter to be current of 530A;
s3, optimizing the electromagnetic stirring technology to reduce the center segregation index, and setting specific parameters of the end electromagnetic stirring as current: 320A, frequency: 15 Hz;
s4, optimizing the tundish nozzle heating process to reduce the superheat degree: the heating mode of the tundish nozzle is natural gas, the heating temperature is 1330 ℃, and the superheat degree is 13 ℃.
The central shrinkage cavity of the produced SWRH82B billet is 0 grade, the central carbon segregation is 1.02, the central porosity is 0 grade, the liquid core size is 53mm, and the isometric crystal proportion is 58%.
Example 3
S1, producing an SWRH82B steel billet by adopting a 160-square small square billet, controlling the ultrahigh pulling speed to be 3.15m/min, and cooling by adopting full water spraying in a secondary cooling process, wherein the specific water amount is 1.8L/kg;
s2, installing liquid core pulse magnetic oscillation equipment, setting the electromagnetic pulse installation position to be 400mm away from the outlet of the crystallizer, and setting the pulse magnetic oscillation process parameter to be 540A;
s3, optimizing the electromagnetic stirring technology to reduce the center segregation index, and setting specific parameters of the end electromagnetic stirring as current: 340A, frequency: 16 Hz;
s4, optimizing the tundish nozzle heating process to reduce the superheat degree: the heating mode of the tundish nozzle is natural gas, the heating temperature is 1330 ℃, and the superheat degree is 18 ℃.
The produced SWRH82B small square billet has a central shrinkage cavity of 0 grade, central carbon segregation of 1.03 grade, central porosity of 0.5 grade, liquid core size of 55mm and isometric crystal proportion of 60 percent.
Example 4
S1, producing an SWRH82B steel billet by adopting a 160-square small square billet, controlling the ultrahigh drawing speed to be 3.60m/min, and cooling by adopting full water spraying in a secondary cooling process, wherein the specific water amount is 2.0L/kg;
s2, installing liquid core pulse magnetic oscillation equipment, setting the electromagnetic pulse installation position to be 600mm away from the outlet of the crystallizer, and setting the pulse magnetic oscillation process parameter to be 600A;
s3, optimizing the electromagnetic stirring technology to reduce the center segregation index, and setting specific parameters of the end electromagnetic stirring as current: 345A, frequency: 16 Hz;
s4, optimizing the tundish nozzle heating process to reduce the superheat degree: the heating mode of the tundish nozzle is natural gas, the heating temperature is 1400 ℃, and the superheat degree is 18 ℃.
The central shrinkage cavity of the produced SWRH82B billet is 0 grade, the central carbon segregation is 1.04, the central porosity is 0 grade, the liquid core size is 54mm, and the isometric crystal proportion is 62%.
Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the invention can be made, and equivalents and modifications of some features of the invention can be made without departing from the spirit and scope of the invention.
Claims (4)
1. A method for improving the internal quality of SWRH82B billet is characterized in that: the method comprises the following steps:
s1, when producing SWRH82B steel billet, adopting the continuous casting ultrahigh pulling speed and superstrong specific water process to control the size and position of the liquid core, which specifically comprises the following steps: the pulling speed is controlled to be 3.15-3.60 m/min, the secondary cooling process is full water spraying cooling, and the specific water amount is 1.6-2.0L/kg;
s2, installing liquid core pulse magnetic oscillation equipment, setting the electromagnetic pulse distance to 200-600mm away from the outlet of the crystallizer, and setting the pulse magnetic oscillation process parameter as current of 500-600A;
s3, setting the specific parameters of terminal electromagnetic stirring as current: 305-345A, frequency: 14-16 Hz;
s4, heating the tundish nozzle by natural gas at 1320-1400 ℃ and 13-18 ℃ superheat degree.
2. A method of improving the internal quality of a SWRH82B billet as claimed in claim 1 wherein: the central shrinkage cavity of the produced SWRH82B billet is 0 grade, the central carbon segregation is 0.99-1.04 grade, and the central porosity is 0-0.5 grade.
3. A method of improving the internal quality of a SWRH82B billet as claimed in claim 1 wherein: wherein the size of the liquid core of S1 is 50-55 mm.
4. A method of improving the internal quality of a SWRH82B billet as claimed in claim 1 wherein: the equiaxed crystal proportion of S2 is not less than 55%.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202111049608.XA CN113751683A (en) | 2021-09-08 | 2021-09-08 | Method for improving internal quality of SWRH82B billet |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202111049608.XA CN113751683A (en) | 2021-09-08 | 2021-09-08 | Method for improving internal quality of SWRH82B billet |
Publications (1)
Publication Number | Publication Date |
---|---|
CN113751683A true CN113751683A (en) | 2021-12-07 |
Family
ID=78793867
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202111049608.XA Pending CN113751683A (en) | 2021-09-08 | 2021-09-08 | Method for improving internal quality of SWRH82B billet |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN113751683A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115138812A (en) * | 2022-07-05 | 2022-10-04 | 上海大学 | Method and device for improving quality of casting blank |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005095968A (en) * | 2003-09-26 | 2005-04-14 | Jfe Steel Kk | Continuous casting method for steel |
US20080164004A1 (en) * | 2007-01-08 | 2008-07-10 | Anastasia Kolesnichenko | Method and system of electromagnetic stirring for continuous casting of medium and high carbon steels |
CN101775461A (en) * | 2010-01-19 | 2010-07-14 | 南京钢铁股份有限公司 | Method for improving central carbon segregation of tire cord steel |
CN106735025A (en) * | 2017-02-09 | 2017-05-31 | 首钢总公司 | A kind of control method of prestress steel continuous small-billet casting center segregation |
CN107904497A (en) * | 2017-12-13 | 2018-04-13 | 西王金属科技有限公司 | A kind of high life bearing steel and its manufacture method |
CN110527917A (en) * | 2019-09-30 | 2019-12-03 | 阳春新钢铁有限责任公司 | 30MnSiBCa hot-rolled wire rod for PC steel bar and preparation method thereof |
CN111534753A (en) * | 2020-05-22 | 2020-08-14 | 江苏永钢集团有限公司 | Chromium alloyed cord steel wire rod and production process thereof |
CN112359277A (en) * | 2020-10-15 | 2021-02-12 | 中天钢铁集团有限公司 | Control method for segregation and net carbon of 86-level high-strength cord steel wire rod |
CN112410679A (en) * | 2020-10-30 | 2021-02-26 | 江苏永钢集团有限公司 | Chromium alloy non-quenched and tempered steel wire rod and production method thereof |
CN113308638A (en) * | 2021-05-27 | 2021-08-27 | 江苏永钢集团有限公司 | Cord steel disc and abnormal structure improvement method thereof |
-
2021
- 2021-09-08 CN CN202111049608.XA patent/CN113751683A/en active Pending
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005095968A (en) * | 2003-09-26 | 2005-04-14 | Jfe Steel Kk | Continuous casting method for steel |
US20080164004A1 (en) * | 2007-01-08 | 2008-07-10 | Anastasia Kolesnichenko | Method and system of electromagnetic stirring for continuous casting of medium and high carbon steels |
CN101775461A (en) * | 2010-01-19 | 2010-07-14 | 南京钢铁股份有限公司 | Method for improving central carbon segregation of tire cord steel |
CN106735025A (en) * | 2017-02-09 | 2017-05-31 | 首钢总公司 | A kind of control method of prestress steel continuous small-billet casting center segregation |
CN107904497A (en) * | 2017-12-13 | 2018-04-13 | 西王金属科技有限公司 | A kind of high life bearing steel and its manufacture method |
CN110527917A (en) * | 2019-09-30 | 2019-12-03 | 阳春新钢铁有限责任公司 | 30MnSiBCa hot-rolled wire rod for PC steel bar and preparation method thereof |
CN111534753A (en) * | 2020-05-22 | 2020-08-14 | 江苏永钢集团有限公司 | Chromium alloyed cord steel wire rod and production process thereof |
CN112359277A (en) * | 2020-10-15 | 2021-02-12 | 中天钢铁集团有限公司 | Control method for segregation and net carbon of 86-level high-strength cord steel wire rod |
CN112410679A (en) * | 2020-10-30 | 2021-02-26 | 江苏永钢集团有限公司 | Chromium alloy non-quenched and tempered steel wire rod and production method thereof |
CN113308638A (en) * | 2021-05-27 | 2021-08-27 | 江苏永钢集团有限公司 | Cord steel disc and abnormal structure improvement method thereof |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115138812A (en) * | 2022-07-05 | 2022-10-04 | 上海大学 | Method and device for improving quality of casting blank |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN111992686B (en) | Aerial fog full-water combined cooling high-carbon steel continuous casting production method | |
CN109055868B (en) | Production method of X80 thick ultra-wide longitudinal submerged arc welding pipeline steel | |
CN111187992B (en) | Production method of continuous casting billet of wire rod for cutting diamond wire | |
CN112501506B (en) | Steel wire rod for bridge cable and manufacturing method thereof | |
CN113751683A (en) | Method for improving internal quality of SWRH82B billet | |
CN113652610A (en) | Ultrahigh-strength stranded wire rod for railway bridge and production process | |
CN108856670A (en) | The production method of low segregation 42CrMo4 series continuous cast round billets | |
CN102319881A (en) | Equipment and method for simultaneously preparing multiple round aluminum alloy ingots | |
CN104399929A (en) | Method for reducing longitudinal division of weather-proof steel continuously cast slab | |
CN114369760A (en) | Wire rod for stress corrosion resistant ultra-high strength steel strand and manufacturing method of steel strand | |
CN113843403B (en) | Method for improving surface cracks of casting blank by using ferrite phase | |
CN114054738A (en) | NM500 wear-resistant steel pouring method capable of avoiding delayed cracks of steel plate | |
CN112743053A (en) | Crystallizer for solving peritectic steel continuous casting slab surface cracks and control method | |
CN111826493B (en) | SWRH82B steel and smelting method thereof | |
CN113198994A (en) | Method for improving subcutaneous negative segregation in large round billet crystallizer in continuous casting process | |
CN108188366B (en) | Magnesium alloy semicontinuous casting grain refinement device and method | |
CN110951975A (en) | Method for smelting TA2 slab ingot by using cold cathode electron beam | |
CN110722330A (en) | Production method of ultra-low carbon steel wire rod for electric conduction | |
CN113927008B (en) | Production method for inhibiting periodic fluctuation of liquid level of dual-phase steel crystallizer for slab production | |
CN110923401A (en) | Method for controlling carbon segregation of high-carbon steel | |
CN113462982A (en) | Wire rod for stranded wire and production process | |
CN114054706B (en) | Production control method for improving pickling low-power quality of bearing steel round steel | |
CN117415298A (en) | Medium-high carbon steel continuous casting method under high drawing speed | |
CN115351254B (en) | Method for improving flaw detection qualification rate of low-alloy medium plate formed by continuous casting head and tail blanks | |
CN118143214A (en) | Compatible operation method of electromagnetic stirring and argon blowing of slab continuous casting crystallizer |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
RJ01 | Rejection of invention patent application after publication |
Application publication date: 20211207 |
|
RJ01 | Rejection of invention patent application after publication |