CN117363954A - Method for reducing dust spot area of U71Mn hot rolled steel rail welded joint - Google Patents
Method for reducing dust spot area of U71Mn hot rolled steel rail welded joint Download PDFInfo
- Publication number
- CN117363954A CN117363954A CN202311202037.8A CN202311202037A CN117363954A CN 117363954 A CN117363954 A CN 117363954A CN 202311202037 A CN202311202037 A CN 202311202037A CN 117363954 A CN117363954 A CN 117363954A
- Authority
- CN
- China
- Prior art keywords
- equal
- hot rolled
- steel rail
- rolled steel
- less
- 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 58
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 48
- 239000010959 steel Substances 0.000 title claims abstract description 48
- 239000000428 dust Substances 0.000 title claims abstract description 15
- 230000008569 process Effects 0.000 claims abstract description 31
- 238000009749 continuous casting Methods 0.000 claims abstract description 24
- 238000003723 Smelting Methods 0.000 claims abstract description 12
- 239000000126 substance Substances 0.000 claims abstract description 10
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 29
- 229910052742 iron Inorganic materials 0.000 claims description 17
- 238000010079 rubber tapping Methods 0.000 claims description 16
- 238000009849 vacuum degassing Methods 0.000 claims description 16
- 238000007664 blowing Methods 0.000 claims description 12
- 238000005266 casting Methods 0.000 claims description 12
- 238000007670 refining Methods 0.000 claims description 12
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 8
- 238000001816 cooling Methods 0.000 claims description 8
- 239000002893 slag Substances 0.000 claims description 8
- 239000000203 mixture Substances 0.000 claims description 6
- 230000004048 modification Effects 0.000 claims description 6
- 238000012986 modification Methods 0.000 claims description 6
- 239000012535 impurity Substances 0.000 claims description 5
- 238000003756 stirring Methods 0.000 claims description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 5
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims description 4
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims description 4
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims description 4
- 235000011941 Tilia x europaea Nutrition 0.000 claims description 4
- 229910052782 aluminium Inorganic materials 0.000 claims description 4
- 229910052786 argon Inorganic materials 0.000 claims description 4
- 229910052788 barium Inorganic materials 0.000 claims description 4
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 claims description 4
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 claims description 4
- 229910052918 calcium silicate Inorganic materials 0.000 claims description 4
- 239000000378 calcium silicate Substances 0.000 claims description 4
- OYACROKNLOSFPA-UHFFFAOYSA-N calcium;dioxido(oxo)silane Chemical compound [Ca+2].[O-][Si]([O-])=O OYACROKNLOSFPA-UHFFFAOYSA-N 0.000 claims description 4
- 238000009826 distribution Methods 0.000 claims description 4
- 230000000694 effects Effects 0.000 claims description 4
- 239000010436 fluorite Substances 0.000 claims description 4
- 238000011065 in-situ storage Methods 0.000 claims description 4
- 239000004571 lime Substances 0.000 claims description 4
- 239000011574 phosphorus Substances 0.000 claims description 4
- 229910052698 phosphorus Inorganic materials 0.000 claims description 4
- 239000000843 powder Substances 0.000 claims description 4
- 239000011593 sulfur Substances 0.000 claims description 4
- 229910052717 sulfur Inorganic materials 0.000 claims description 4
- 238000003825 pressing Methods 0.000 claims description 3
- 238000009966 trimming Methods 0.000 claims 1
- 239000000463 material Substances 0.000 abstract description 2
- 238000005096 rolling process Methods 0.000 description 8
- 238000003466 welding Methods 0.000 description 7
- 238000006477 desulfuration reaction Methods 0.000 description 3
- 230000023556 desulfurization Effects 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 238000005452 bending Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 230000002572 peristaltic effect Effects 0.000 description 2
- 238000012797 qualification Methods 0.000 description 2
- 239000000498 cooling water Substances 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
Classifications
-
- 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
- B22D11/001—Continuous casting of metals, i.e. casting in indefinite lengths of specific alloys
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/28—Manufacture of steel in the converter
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0075—Treating in a ladle furnace, e.g. up-/reheating of molten steel within the ladle
-
- 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
- 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
-
- 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
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Mechanical Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention discloses a method for reducing the dust spot area of a U71Mn hot rolled steel rail welded joint, and belongs to the technical field of metallurgical materials. The method for reducing the dust spot area of the U71Mn hot rolled steel rail welded joint can effectively reduce the dust spot area of the steel rail welded joint by optimizing the contents of Si, mn and V in chemical components of a continuous casting blank for producing the steel rail and controlling smelting process parameters.
Description
Technical Field
The invention belongs to the technical field of preparation of rolled easily-welded U71Mn hot rolled steel rail materials, and particularly relates to a method for reducing the dust spot area of a U71Mn hot rolled steel rail welded joint.
Background
At present, the high-speed railway rails in China mainly comprise U71MnG and U75VG, wherein U71MnG has the advantages of high toughness, fatigue resistance and the like, and is widely applied to the high-speed railway in China, but along with the increase of the consumption, a plurality of problems are gradually found: as shown in FIG. 1, the conventional U71Mn typical gray-spot fracture is a photograph, and the gray-spot area of the fracture is larger (the average statistical area is 12.2mm 2 ) This significantly reduces the weldability of the rail.
Disclosure of Invention
In order to solve the problems, the invention provides a method for reducing the dust spot area of a welding joint of a U71Mn hot rolled steel rail, which comprises the following steps of adjusting the chemical components of a continuous casting blank for producing the U71Mn hot rolled steel rail according to mass percent: c0.65-0.75%; si 0.20-0.30%; mn 0.75-0.80%; p is less than or equal to 0.025%; s is less than or equal to 0.006%; v0.02-0.03%, and Fe and unavoidable impurities in balance;
the method comprises the following processes: molten iron pretreatment, converter smelting, LF refining, VD vacuum degassing and continuous casting;
in the continuous casting process, protection casting is adopted, low-aluminum casting powder is adopted, weak cold water distribution is adopted in the secondary cooling section, the whole-process constant-pulling-speed operation is adopted, the pulling speed is 6.2-6.8m/min, the electric stirring and the light pressing of the casting machine are started, and the quality of the continuous casting blank is ensured.
In some embodiments, in the molten iron pretreatment process, the sulfur content in the molten iron is controlled to be less than or equal to 0.010 percent, and the phosphorus content is controlled to be less than or equal to 0.10 percent.
In some embodiments, in the converter smelting process, the content of tapping C is controlled to be more than or equal to 0.08%, the tapping temperature is controlled to be more than or equal to 1550 ℃, lime, calcium silicate barium and fluorite are added after tapping, deoxidization and slag modification are performed, the argon blowing effect is ensured in the tapping process, and the slag is free from caking phenomenon when molten steel is refined in place.
In some embodiments, in the LF refining process, desulfurization is performed according to the composition and temperature of molten steel of a converter, and the composition fine adjustment and the temperature rising operation are required to be performed, wherein the refining in-situ temperature is more than or equal to 1530 ℃.
In some embodiments, in the VD vacuum degassing process, the deep vacuum degassing time is not less than 16min, soft blowing is not less than 20min after vacuum degassing, the soft blowing is performed at Cheng Yaqi flow, and the molten steel is not exposed due to peristaltic motion.
The method for reducing the dust spot area of the U71Mn hot rolled steel rail welded joint based on the technical proposal can effectively reduce the dust spot area of the U71Mn hot rolled steel rail welded joint (the average dust spot area of the steel rail fracture is typically 12.2 mm) by effectively controlling the content of chemical components (especially Si and V) in the U71Mn hot rolled steel rail and combining with controlling smelting process parameters 2 Reduced to 4.1mm 2 The welding performance of the U71Mn hot rolled steel rail can be effectively improved, and the obtained U71Mn hot rolled steel rail has good comprehensive mechanical properties, and meets the following requirements: the yield strength is more than or equal to 515MPa, the tensile strength is more than or equal to 924MPa, the elongation is more than or equal to 12.0%, and the Brinell hardness average value is more than or equal to 272HB. Therefore, the method provided by the invention is suitable for large-scale popularization and application.
Drawings
FIG. 1 is a photograph of a typical gray spot fracture of a conventional U71 Mn.
Detailed Description
The present invention aims to provide a method for reducing the dust spot area of a welded joint of a U71Mn hot rolled steel rail and thereby to provide a (easily welded) U71Mn hot rolled steel rail.
The method for reducing the ash spot area of the welded joint of the U71Mn hot rolled steel rail comprises the following steps of adjusting chemical components of a continuous casting blank for producing the U71Mn hot rolled steel rail according to mass percent: c0.65-0.75%; si 0.20-0.30%; mn 0.75-0.80%; p is less than or equal to 0.025%; s is less than or equal to 0.006%; v0.02-0.03%, and Fe and unavoidable impurities in balance;
the method specifically comprises the following processes: molten iron pretreatment, converter smelting, LF refining, VD vacuum degassing and continuous casting; wherein:
in the molten iron pretreatment process, the sulfur content in molten iron is controlled to be less than or equal to 0.010 percent, and the phosphorus content is controlled to be less than or equal to 0.10 percent;
in the converter smelting process, the content of tapping C is controlled to be more than or equal to 0.08%, the tapping temperature is controlled to be more than or equal to 1550 ℃, lime, calcium silicate barium and fluorite are added after tapping, deoxidation and slag modification are carried out, the argon blowing effect is ensured in the tapping process, and the slag is not blocked when molten steel is refined in place;
in the LF refining process, desulfurization is carried out according to the components and the temperature of the molten steel of the converter, and the components are finely adjusted and the temperature is increased, so that the refining in-situ temperature is required to be more than or equal to 1530 ℃;
in the VD vacuum degassing process, the deep vacuum degassing time is not less than 16min, soft blowing is not less than 20min after vacuum degassing, the flow rate of soft blowing Cheng Yaqi is stable, and the molten steel is not exposed due to creeping;
in the continuous casting process, protection casting is adopted, low-aluminum casting powder is adopted, weak cold water distribution is adopted in the second cooling section, the whole-process constant pulling speed operation is adopted, the pulling speed is 6.2-6.8m/min, the electric stirring and the light pressing of the casting machine are started, and the quality of the continuous casting blank is ensured;
wherein the chemical components of the continuous casting blank are selected from the following components in percentage by mass: c0.70-0.75%; si 0.21-0.30%; mn0.76-0.78%; p is less than or equal to 0.015 percent; s is less than or equal to 0.004%; v0.02-0.03%, and Fe and unavoidable impurities in balance.
The method for reducing the dust spot area of the U71Mn hot rolled steel rail welding joint provided by the invention can effectively reduce the dust spot area of the U71Mn hot rolled steel rail welding joint by controlling the contents of Si and Mn in the smelting process and adding a proper amount of V element and combining with strictly controlled smelting process parameters.
Continuous casting slab obtained based on the methodThe rolling of the universal rolling mill of the rail passing beam factory (continuous casting billet heating, universal rolling mill rolling, cooling and pre-bending by a cooling bed and straightening) can provide a U71Mn hot rolled steel rail, which comprises the following chemical components in percentage by mass: c0.65-0.75%; si 0.20-0.30%; mn 0.75-0.80%; p is less than or equal to 0.025%; s is less than or equal to 0.006%; v0.02-0.03%, and Fe and unavoidable impurities in balance. The U71Mn hot rolled steel rail has smaller fracture gray spot area, and the average fracture gray spot area can reach 4.1mm 2 The welding qualification rate can be further improved, and meanwhile, the welding qualification rate also has good comprehensive mechanical properties, and meets the following requirements: the yield strength is more than or equal to 515MPa, the tensile strength is more than or equal to 924MPa, the elongation is more than or equal to 12.0%, and the Brinell hardness average value is more than or equal to 272HB.
The following describes the invention in detail by way of specific examples, which are intended to aid in understanding the invention and are not intended to limit the invention.
Example 1
The method sequentially comprises the following steps: molten iron pretreatment, converter smelting, LF refining, VD vacuum degassing and continuous casting to produce a continuous casting blank of a U71Mn hot rolled steel rail, wherein the chemical components and the content of the continuous casting blank are shown in the following table 1; and then the U71Mn hot rolled steel rail is produced by the following procedures: heating a continuous casting blank, descaling by high-pressure water, rolling by a universal rolling mill, cooling by a cooling bed, pre-bending, straightening, flaw detection, processing, checking and warehousing; wherein:
in the molten iron pretreatment process, the sulfur content in molten iron is controlled to be 0.010 percent, and the phosphorus content is controlled to be 0.10 percent;
in the converter smelting process, the content of tapping C is controlled to be more than or equal to 0.08%, the tapping temperature is controlled to be more than or equal to 1550 ℃, lime, calcium silicate barium and fluorite are added after tapping, deoxidation and slag modification are carried out, the argon blowing effect is ensured in the tapping process, and the slag is not blocked when molten steel is refined in place;
in the LF refining process, desulfurization is carried out according to the components and the temperature of the molten steel of the converter, and the components are finely adjusted and the temperature is increased, so that the refining in-situ temperature is required to be more than or equal to 1530 ℃;
in the VD vacuum degassing process, the deep vacuum degassing time is 16min, soft blowing is carried out for 20min after vacuum degassing, the soft blowing is carried out for Cheng Yaqi, the flow is stable, and the peristaltic movement of molten steel is not exposed;
in the continuous casting process, protection casting is adopted, low-aluminum casting powder is adopted, weak cold water distribution is adopted in the second cooling section, the whole-process constant pulling speed operation is adopted, the pulling speed is 6.5m/min, the electromagnetic stirring and the light reduction of the casting machine are started, the electromagnetic stirring light reduction parameters of the second cooling water and the reduction of each withdrawal straightening machine are set, and the quality of continuous casting billets is ensured; and rolling the continuous casting blank by a universal rolling mill in a rail girder factory to obtain the steel rail.
Examples 2 to 3 were conducted in accordance with the procedure of example 1 except that the chemical composition content of the continuous casting slab was different from that of example 1, and are specifically shown in the following table 1.
The mechanical properties of the U71Mn hot rolled steel rails obtained in examples 1 to 3 were examined, and the results are shown in the following table 2, and the fracture gray spot areas of the U71Mn hot rolled steel rails obtained in examples 1 to 3 were examined, and the results are shown in the following table 3.
Table 1: chemical composition and content (%)
Table 2: mechanical properties of the rails of the various embodiments
Table 3: rail break gray spot area of each embodiment
| Examples | Statistical average (mm) of the areas of the broken spots of the steel rail 2 ) |
| 1 | 4.1 |
| 2 | 4.0 |
| 3 | 3.8 |
As can be seen from the above Table 2, the U71Mn hot rolled steel rails produced in examples 1-3 all have good mechanical properties, satisfying the following: the yield strength is more than or equal to 515MPa, the tensile strength is more than or equal to 924MPa, the elongation is more than or equal to 12.0%, and the Brinell hardness average value is more than or equal to 272HB. As can be seen from Table 3 above, the U71Mn hot rolled steel rails produced in examples 1-3 have smaller areas of broken gray spots, both being 4.1mm 2 Below, the cross-sectional area of the dust spot is far lower than that of the conventional U71Mn (12.2 mm 2 ) Therefore, the method provided by the invention can obviously reduce the fracture gray spot area of the U71Mn hot rolled steel rail, further can effectively improve the welding performance of the U71Mn hot rolled steel rail, and has good popularization value.
Finally, it should be noted that: the foregoing description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but 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 modifications may be made to the technical solutions described in the foregoing embodiments, or that equivalents may be substituted for part of the technical features thereof. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (5)
1. A method for reducing the dust spot area of a welded joint of a U71Mn hot rolled steel rail, comprising the steps of adjusting the chemical composition of a continuous casting blank for producing the U71Mn hot rolled steel rail according to mass percent: c0.65-0.75%; si 0.20-0.30%; mn0.75-0.80%; p is less than or equal to 0.025%; s is less than or equal to 0.006%; v0.02-0.03%, and Fe and unavoidable impurities in balance;
the method comprises the following processes: molten iron pretreatment, converter smelting, LF refining, VD vacuum degassing and continuous casting;
in the continuous casting process, protection casting is adopted, low-aluminum casting powder is adopted, weak cold water distribution is adopted in the secondary cooling section, the whole-process constant-pulling-speed operation is adopted, the pulling speed is 6.2-6.8m/min, the electric stirring and the light pressing of the casting machine are started, and the quality of the continuous casting blank is ensured.
2. The method of claim 1, wherein the sulfur content in the molten iron is controlled to be less than or equal to 0.010% and the phosphorus content is controlled to be less than or equal to 0.10% in the molten iron pretreatment process.
3. The method according to claim 1 or 2, wherein in the converter smelting process, the content of tapping C is controlled to be more than or equal to 0.08%, the tapping temperature is controlled to be more than or equal to 1550 ℃, lime, calcium silicate barium and fluorite are added after tapping, deoxidation and slag modification are carried out, the argon blowing effect is ensured in the tapping process, and slag is not agglomerated when molten steel is refined in place.
4. A method according to any one of claims 1-3, wherein in the LF refining process, desulphurisation, component trimming and temperature increasing operations are performed according to converter steel composition and temperature, requiring refining in-situ temperatures > 1530 ℃.
5. The method of any one of claims 1-4, wherein in the VD vacuum degassing process, the deep vacuum degassing time is not less than 16min, the soft blowing after vacuum degassing is not less than 20min, the soft blowing through Cheng Yaqi flow is stable, and the molten steel is not exposed to creep.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311202037.8A CN117363954A (en) | 2023-09-18 | 2023-09-18 | Method for reducing dust spot area of U71Mn hot rolled steel rail welded joint |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311202037.8A CN117363954A (en) | 2023-09-18 | 2023-09-18 | Method for reducing dust spot area of U71Mn hot rolled steel rail welded joint |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117363954A true CN117363954A (en) | 2024-01-09 |
Family
ID=89390111
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311202037.8A Pending CN117363954A (en) | 2023-09-18 | 2023-09-18 | Method for reducing dust spot area of U71Mn hot rolled steel rail welded joint |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117363954A (en) |
-
2023
- 2023-09-18 CN CN202311202037.8A patent/CN117363954A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN115369305A (en) | Smelting method of easily-welded high-speed steel rail | |
| CN112877586A (en) | Production method of high-strength and high-toughness American-standard steel rail for CR175 crane | |
| CN103556055A (en) | Hot-rolled H-shaped steel for marine natural gas extraction platform structure and production method of hot-rolled H-shaped steel | |
| CN107974615A (en) | Thickness is less than the Q460E high strength steel plates and its production method of 12mm | |
| CN109112246B (en) | Production method of steel wire rod for railway elastic strip fastener formed by direct cold bending | |
| CN111334717A (en) | Method for producing 60kg/m steel rail by using 320mm × 415mm casting blank | |
| CN115058636A (en) | Production method of European standard R370CrHT on-line heat treatment steel rail | |
| CN111334718A (en) | European standard R260Mn steel rail and production method thereof | |
| CN111485171A (en) | Steel rail material for heavy haul railway and production method thereof | |
| CN114150218A (en) | Q355NE hot-rolled round steel for high-speed rail bogie and production process | |
| CN113699431A (en) | Method for reducing surface cracks of low alloy steel | |
| CN101748243B (en) | Method for preparing spring steel | |
| CN117363954A (en) | Method for reducing dust spot area of U71Mn hot rolled steel rail welded joint | |
| CN116716552A (en) | Smelting method for reducing dust spot area of high-speed steel rail welding joint | |
| CN115029506A (en) | Production method of carbon steel rail with American standard strength | |
| CN115491576A (en) | Smelting continuous casting method of rare earth microalloyed 355 MPa-level low-cost hot-rolled H-shaped steel | |
| CN114807773A (en) | High-mechanical-property steel for wind driven generator shaft and preparation process thereof | |
| CN115029613A (en) | Preparation method of high-strength weather-resistant low-temperature-resistant YQ450NQR1 steel | |
| CN113774267A (en) | Rolling method of high-strength high-hardness corrosion-resistant pearlitic steel | |
| CN116716553A (en) | Smelting method for improving drop hammer qualification rate of high-speed steel rail | |
| CN117051329A (en) | U71MnCr steel rail with good welding quality and smelting method thereof | |
| CN117026076A (en) | Smelting method of microalloyed high-speed steel rail | |
| CN112375977A (en) | Rare earth microalloyed seamless steel tube for Q390 steel grade structure and production method thereof | |
| CN114457287A (en) | High-strength steel for saw blade and production method thereof | |
| CN117051312A (en) | Smelting production method for high-strength heat-treated steel rail with outlet beauty |
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 |