CN116042960A - Production process for preventing bubbles from occurring in smelting H08A steel casting blank - Google Patents
Production process for preventing bubbles from occurring in smelting H08A steel casting blank Download PDFInfo
- Publication number
- CN116042960A CN116042960A CN202310059822.6A CN202310059822A CN116042960A CN 116042960 A CN116042960 A CN 116042960A CN 202310059822 A CN202310059822 A CN 202310059822A CN 116042960 A CN116042960 A CN 116042960A
- Authority
- CN
- China
- Prior art keywords
- slag
- aluminum
- minutes
- molten steel
- smelting
- 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
Classifications
-
- 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
- C21C7/0006—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
- C21C7/0056—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00 using cored wires
-
- 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
- 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
- C22C33/06—Making ferrous alloys by melting using master alloys
-
- 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)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention discloses a production process for preventing bubbles from occurring in smelting H08A steel casting blanks, refining molten steel to fix oxygen, adding aluminum ferromanganese to perform precipitation deoxidation, wherein the addition of the aluminum ferromanganese is performed according to the standard that 10kg of aluminum ferromanganese is dehydrated to 12ppm of oxygen and less than 100ppm of oxygen; adding lime 6kg/t after 2 minutes of power transmission for slagging, adding deoxidizer 0.5kg/t and aluminum slag ball 3kg/t after slag melting, further deoxidizing and slagging, smelting for 10 minutes, sampling and analyzing, adding low-carbon ferromanganese alloy 0.9kg/t and silicon-calcium alloy 0.3kg/t according to the components of molten steel [ Si ], [ Mn ], and adding lime 2kg/t and aluminum slag ball 0.5-1kg/t in batches according to slag color; the refining furnace must keep the tapping of yellow and white slag above 10 minutes, low silicon ferrotitanium alloy is added before tapping, about 0.4kg/t, soft blowing can be performed above 8 minutes after feeding pure calcium wire, the refining furnace is controlled according to internal control components, and the requirements of [ Si ] are more than or equal to 0.020-0.025%, [ Ti ] is 0.08% -0.012%, and [ Al ] is more than or equal to 0.0030%. The [ Si ] and [ Ti ] components are controlled by the neutral line.
Description
Technical Field
The invention relates to a production process for preventing bubbles from occurring in smelting H08A steel casting blanks.
Background
In the metallurgical industry, H08A welding bar steel is used for producing welding rods, and the H08A welding bar steel has the characteristics that chemical components are required to meet standard component requirements, and the quality of casting blanks must not have the defects of shrinkage porosity, shrinkage cavity, bubbles and the like. Ensuring good deoxidization degree of molten steel in the smelting process of H08A welding rod steel is a key for ensuring casting blank quality.
H08A welding strip steel is an important raw material for producing welding rods, belongs to low-carbon, low-silicon and low-aluminum steel grades, and one of the biggest differences with other steel grades is to ensure the chemical composition of the finished steel, and the national standard composition of the steel is less than or equal to 0.03 percent and less than or equal to 0.10 percent. The deoxidization process is particularly important in the production of H08A welding rod steel, if deoxidization Cheng Duguo is strong, the phenomenon of increasing [ Si ] can be caused, the [ Si ] component exceeds the standard, a large amount of inclusions generated in the deoxidization process can block a tundish nozzle to influence the castability of molten steel and the forward running of continuous casting, but if deoxidization is insufficient, the oxygen content in the molten steel is higher, and air bubbles can be generated in a casting blank in the casting process. Therefore, the production of H08A welding rod steel needs to make a reasonable molten steel deoxidizing system, and especially the quality and the castability of a casting blank are controlled.
The control of the endpoint [ Si ] component of 0.020-0.030% in the current smelting process of H08A welding rod steel is the first choice smelting process for avoiding the occurrence of bubbles in casting blanks. The process method mainly comprises the following deoxidizing agents are added according to the total amount of molten steel in a converter deoxidizing alloying process: adding composite deoxidizer, aluminum-iron alloy, low-silicon-titanium-iron alloy, aluminum-manganese-iron alloy, silicon-calcium alloy and the like into a steel ladle, using low-aluminum slag balls, calcium carbide powder and the like for slagging in an LF refining furnace, adding silicon-calcium alloy to finely adjust the [ Si ] component to 0.020% -0.025%, and then feeding pure calcium wires into the steel ladle for calcium treatment. Although the smelting process avoids the negative influence on the quality of the casting blank to a certain extent, the problem of casting blank bubbles still exists in the casting process of molten steel. In order to thoroughly eliminate the problem of casting blank bubbles in the casting process of H08A welding rod steel, the existing technology is based on the control of the end point [ Si ] component of an LF refining furnace according to 0.020% -0.025%, 0.2-0.3kg/t ferrotitanium alloy is added into molten steel for final deoxidation 3 minutes before wire feeding according to the [ Ti ] component in the molten steel, so that the molten steel contains a certain amount of [ Ti ] component, the oxidation of the [ Si ] component is furthest reduced in the casting process, and the problem of casting blank bubbles in the casting process of H08A welding rod steel is fundamentally solved.
Search the following documents considered: (1) Haiming "external refining technology of electric furnace molten steel" Beijing metallurgical industry Press-2010 for comparing deoxidation capacities of different deoxidizers in LF; (2) Gao Zeping Beijing Metallurgical industry Press 2011, steelmaking technology, deoxidization and alloying System; (3) Zheng Jinxing, wang Zhenguang and Wang Qingchun "steelmaking Process and Equipment" Beijing metallurgical industry Press 2011 for deoxidizing and nonmetallic inclusions; it is known that no system exists at present to effectively solve the problem of bubble of casting blank of H08A welding rod steel, which causes that numerous steel factories in China have the problem of bubble of casting blank in the process of producing H08A welding rod steel, and the quality of products is affected, so that the problem of bubble of H08A is thoroughly solved at present.
Disclosure of Invention
The invention aims to provide a production process for preventing bubbles from occurring in smelting H08A steel casting blanks, which can improve the quality of casting blanks to the maximum extent, and prevent quality defects such as subcutaneous bubbles and the like from occurring in the casting process of the casting blanks, and has remarkable effect.
The technical scheme adopted by the invention is that the production process for preventing bubbles from occurring in smelting the H08A steel casting blank is implemented according to the following steps:
(1) Firstly, oxygen is determined after refined molten steel enters a station, aluminum ferromanganese is added according to the oxygen content of the molten steel to carry out precipitation deoxidation, and the addition of the aluminum ferromanganese is carried out according to the standard that 10kg of the aluminum ferromanganese is dehydrated to 12ppm of oxygen and less than 100ppm of oxygen;
(2) Adding lime 6kg/t for slagging after 2 minutes of power transmission, adding deoxidizer 0.5kg/t and aluminum slag ball 3kg/t for further deoxidization and slagging after the slag is melted, and avoiding long-time low-grade heat preservation operation to reduce carburetion of the electrode;
(3) Sampling and analyzing after smelting for 10 minutes, adding 0.9kg/t of low-carbon ferromanganese alloy and 0.3kg/t of calcium-silicon alloy adjusting components according to the [ Si ] and [ Mn ] components of molten steel, and adding 2kg/t of lime and 0.5-1kg/t of aluminum slag balls in batches according to the color of slag;
(4) The refining furnace is required to keep tapping above yellow and white slag for more than 10 minutes, low-silicon ferrotitanium alloy is added before tapping, about 0.4kg/t is added, tapping can be performed after soft blowing is performed for more than 8 minutes after pure calcium wire is fed, the soft blowing state slightly fluctuates with the slag surface, and molten steel is not exposed as a standard;
(5) The refining furnace is controlled according to the internal control components, and the requirements of [ Si ] are more than or equal to 0.020-0.025%, [ Ti ] is 0.08-0.012%, and [ Al ] is more than or equal to 0.0030%. The [ Si ] and [ Ti ] components are controlled by the neutral line.
According to the characteristic that the H08A welding strip steel strictly controls oxygen activity in smelting and casting processes and the characteristic that the bonding capability of Ti element and O is stronger than that of Si element, according to a metallurgical transmission theory, the secondary oxidation of [ Si ] component caused by insufficient final deoxidization in the smelting and casting processes of the H08A welding strip steel is analyzed theoretically, so that the defect of bubble appears in a casting blank, the probability of bubble appearing in the casting blank can be inhibited to the greatest extent by adding a proper amount of low-silicon ferrotitanium alloy, and meanwhile, the grain can be refined by adding a proper amount of low-silicon ferrotitanium alloy into molten steel before the smelting of an LF furnace, so that the welding performance is improved, and the quality of the H08A welding strip steel is optimized. The process can be used as an important means for improving the qualification rate of products in the steelmaking production of H08A welding rod steel, and can be directly used for steelmaking.
In the smelting process of H08A welding strip steel, ti element with stronger affinity with oxygen is selected as a final deoxidizing element according to the strength sequence of alloy element and oxygen affinity, and a proper amount of low-silicon ferrotitanium alloy is added into molten steel before the smelting of an LF furnace is finished, and then Ca wire is fed, so that the oxygen activity in the molten steel is controlled to be about 15-20ppm, the probability of casting blank bubbles is reduced, and the casting property of continuous casting is ensured.
The chemical reaction sequence between oxygen and [ Ca ], [ Si ], [ Ti ], [ Al ] in molten steel in the smelting and casting process of the LF furnace is as follows:
[Ca]+[O]=(CaO)(S) (1)
3[Al]+2[O]=(Al 2 O 3 )(S) (2)
[Ti]+2[O]=(TiO 2 )(S) (3)
[Si]+2[O]=(SiO 2 )(S) (4)
the affinity of [ Ca ], [ Al ], [ Ti ] elements with oxygen is slightly stronger than that of [ Si ] elements, a secondary oxidation process of molten steel occurs under the casting condition of H08A welding strip steel, the [ Ca ], [ Al ] elements in the molten steel are preferentially oxidized, and redundant oxygen can be combined with the [ Ti ], [ Si ] elements in the molten steel, so that the carbon-oxygen reaction is furthest inhibited; therefore, the inventor considers that adding a proper amount of low-silicon ferrotitanium into molten steel before the smelting of the LF furnace is finished, the secondary oxidation reaction degree is restrained, the probability of casting blank bubbles in the smelting and casting processes of the molten steel is avoided, and the purpose of improving the blank forming rate of H08A welding strip steel is achieved.
Taking an 80t converter and a steel plant provided with an 80t LF refining furnace for smelting H08A welding strip steel as an example test, the process is implemented to realize the achievement that the qualification rate of 50 furnaces for continuous casting of H08A welding rod steel reaches 100%, and the test data are shown in the following table:
table 1
It can be seen from the test that:
(1) Before the smelting of the LF refining furnace is finished, 0.4kg/t low-silicon Tai-Fe alloy is added according to the deoxidization degree and the molten steel [ Al ] and [ Ti ] components, the LF endpoint [ Ti ] component is controlled to be about 0.008-0.013%, and the probability of generating bubbles of a casting blank caused by secondary oxidation in the casting process is furthest inhibited.
(2) The method is characterized in that 1.2-1.5m/t pure calcium wire is fed into molten steel to improve the morphology of inclusions in the molten steel, so that the inclusions can be floated and removed to the greatest extent, and the fluidity and the castability of the molten steel are ensured.
(3) After the pure calcium wire is fed, soft blowing is carried out for 8 minutes, tapping is carried out, and continuous casting is carried out according to a protection pouring process.
In the continuous production process of H08A welding strip steel, the final deoxidization work is finished by adding a proper amount of low-silicon ferrotitanium alloy into molten steel before the smelting of an LF furnace is finished, so that the product percent of pass is improved. After the process is implemented to continuously produce H08A welding strip steel according to the weight of 2t of each casting blank, the cost can be saved after 1t of waste blank is reduced: 1t x 4390 yuan/t=4390 yuan (tax-containing tariffs of H08A steel are calculated according to the price of 4390 yuan/ton). The invention starts from the practical production, the designed new process can effectively control the casting blank quality and the casting property of molten steel, improves the casting blank quality of H08A welding strip steel, explores an effective process method for preventing the bubble defect of the casting blank of the H08A welding strip steel, and has remarkable effect after the new process is put into a steel mill.
Detailed Description
A production process for preventing bubbles from occurring in smelting H08A steel cast blanks takes an 80t converter as an example, a steelworks equipped with an 80t LF refining furnace is used for smelting H08A welding strip steel, and the process is implemented to realize the achievement that the qualification rate of 50 furnaces for continuous casting H08A welding rod steel reaches 100 percent, and is implemented according to the following steps:
(1) Firstly, oxygen is determined after refined molten steel enters a station, aluminum ferromanganese is added according to the oxygen content of the molten steel to carry out precipitation deoxidation, and the addition of the aluminum ferromanganese is carried out according to the standard that 10kg of the aluminum ferromanganese is dehydrated to 12ppm of oxygen and less than 100ppm of oxygen;
(2) Adding lime 6kg/t for slagging after 2 minutes of power transmission, adding deoxidizer 0.5kg/t and aluminum slag ball 3kg/t for further deoxidization and slagging after the slag is melted, and avoiding long-time low-grade heat preservation operation to reduce carburetion of the electrode;
(3) Sampling and analyzing after smelting for 10 minutes, adding 0.9kg/t of low-carbon ferromanganese alloy and 0.3kg/t of calcium-silicon alloy adjusting components according to the [ Si ] and [ Mn ] components of molten steel, and adding 2kg/t of lime and 0.5-1kg/t of aluminum slag balls in batches according to the color of slag;
(4) The refining furnace is required to keep tapping above yellow and white slag for more than 10 minutes, low-silicon ferrotitanium alloy is added before tapping, about 0.4kg/t is added, tapping can be performed after soft blowing is performed for more than 8 minutes after pure calcium wire is fed, the soft blowing state slightly fluctuates with the slag surface, and molten steel is not exposed as a standard;
(5) The refining furnace is controlled according to the internal control components, and the requirements of [ Si ] are more than or equal to 0.020-0.025%, [ Ti ] is 0.08-0.012%, and [ Al ] is more than or equal to 0.0030%. The [ Si ] and [ Ti ] components are controlled by the neutral line.
Claims (1)
1. The production process for preventing bubbles from occurring in smelting H08A steel casting is characterized by comprising the following steps of:
(1) Firstly, oxygen is determined after refined molten steel enters a station, aluminum ferromanganese is added according to the oxygen content of the molten steel to carry out precipitation deoxidation, and the addition of the aluminum ferromanganese is carried out according to the standard that 10kg of the aluminum ferromanganese is dehydrated to 12ppm of oxygen and less than 100ppm of oxygen;
(2) Adding lime 6kg/t for slagging after 2 minutes of power transmission, adding deoxidizer 0.5kg/t and aluminum slag ball 3kg/t for further deoxidization and slagging after the slag is melted, and avoiding long-time low-grade heat preservation operation to reduce carburetion of the electrode;
(3) Sampling and analyzing after smelting for 10 minutes, adding 0.9kg/t of low-carbon ferromanganese alloy and 0.3kg/t of calcium-silicon alloy adjusting components according to the [ Si ] and [ Mn ] components of molten steel, and adding 2kg/t of lime and 0.5-1kg/t of aluminum slag balls in batches according to the color of slag;
(4) The refining furnace is required to keep tapping above yellow and white slag for more than 10 minutes, low-silicon ferrotitanium alloy is added before tapping, about 0.4kg/t is added, tapping can be performed after soft blowing is performed for more than 8 minutes after pure calcium wire is fed, the soft blowing state slightly fluctuates with the slag surface, and molten steel is not exposed as a standard;
(5) The refining furnace is controlled according to the internal control components, and the requirements of [ Si ] are more than or equal to 0.020-0.025%, [ Ti ] is 0.08-0.012%, and [ Al ] is more than or equal to 0.0030%. The [ Si ] and [ Ti ] components are controlled by the neutral line.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310059822.6A CN116042960A (en) | 2023-01-20 | 2023-01-20 | Production process for preventing bubbles from occurring in smelting H08A steel casting blank |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310059822.6A CN116042960A (en) | 2023-01-20 | 2023-01-20 | Production process for preventing bubbles from occurring in smelting H08A steel casting blank |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116042960A true CN116042960A (en) | 2023-05-02 |
Family
ID=86127125
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310059822.6A Pending CN116042960A (en) | 2023-01-20 | 2023-01-20 | Production process for preventing bubbles from occurring in smelting H08A steel casting blank |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116042960A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114959426A (en) * | 2022-05-09 | 2022-08-30 | 包头钢铁（集团）有限责任公司 | Preparation method of metal material for automobile brake cable |
-
2023
- 2023-01-20 CN CN202310059822.6A patent/CN116042960A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114959426A (en) * | 2022-05-09 | 2022-08-30 | 包头钢铁（集团）有限责任公司 | Preparation method of metal material for automobile brake cable |
Non-Patent Citations (2)
| Title |
|---|
| 杨怀春等: "H08A铸坯气泡的原因分析及控制", 新疆钢铁, no. 1, pages 29 - 31 * |
| 贯生金等: "天钢LD-LF-CC流程冶炼H08A的生产工艺优化", 天津冶金, no. 4, pages 24 - 26 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108396097B (en) | Smelting method of low-Ca and low-Al welding wire steel | |
| CN114085953B (en) | Control method for acid dissolution of aluminum in aluminum-containing cold heading steel | |
| CN102776323B (en) | Smelting method of steel for hypoxia axle | |
| KR20130025383A (en) | Method for controlling titanium content in ultra-low carbon killed steel | |
| CN102816979A (en) | Production method of low-carbon sulfur series free-cutting steel continuous casting billet | |
| CN114395657B (en) | High-cleanness electroslag bearing steel for railway freight car and smelting method thereof | |
| CN109402327B (en) | External refining production method of ultrapure high-carbon chromium bearing steel | |
| CN112442572A (en) | Deoxidation control method for high-end bearing steel inclusion | |
| CN102851447B (en) | Outside-furnace refining production method of steel used in carbon steel welding wire | |
| CN114182156A (en) | Production method of low-aluminum carbon structural molten steel | |
| CN113564447B (en) | Vanadium-controlled Cr13 type hydroelectric stainless steel smelting method | |
| CN111793772A (en) | High-standard bearing steel efficient production process | |
| CN115261706A (en) | Preparation method of martensitic stainless steel continuous casting round billet for photovoltaic glass calendering roll | |
| CN114657323A (en) | Deep desulfurization method for LF (ladle furnace) | |
| CN115261564B (en) | Pure iron as non-aluminum deoxidizing material for amorphous soft magnetic thin belt and preparation method thereof | |
| CN110714161A (en) | High-sulfur free-cutting steel for automobile and production process thereof | |
| CN112481550B (en) | Smelting process of lanthanum-cerium-rare earth alloy die steel | |
| CN116042949A (en) | Production method for non-refining treatment of low-carbon low-silicon steel | |
| CN116042960A (en) | Production process for preventing bubbles from occurring in smelting H08A steel casting blank | |
| CN110923405B (en) | Process control method for reducing hydrogen hazard in steel rail | |
| CN113106349A (en) | Alloy welding wire steel wire rod and preparation method thereof | |
| CN109182648B (en) | Method for producing sulfur-containing free-cutting steel by utilizing desulfurized and slagging-off iron | |
| CN112322836A (en) | Step-by-step deoxidation operation method suitable for low-carbon steel | |
| CN112159925A (en) | Production process of high-strength and high-toughness anchor rod steel billet | |
| CN112708728A (en) | Method for improving plasticity of non-metallic inclusion in aluminum deoxidized steel/aluminum-containing steel and steel |
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 |