CN100567512C - A kind of nitrogen content control method for smelting stainless steel by vacuum oxygen decarburization device - Google Patents
A kind of nitrogen content control method for smelting stainless steel by vacuum oxygen decarburization device Download PDFInfo
- Publication number
- CN100567512C CN100567512C CNB2007100385292A CN200710038529A CN100567512C CN 100567512 C CN100567512 C CN 100567512C CN B2007100385292 A CNB2007100385292 A CN B2007100385292A CN 200710038529 A CN200710038529 A CN 200710038529A CN 100567512 C CN100567512 C CN 100567512C
- Authority
- CN
- China
- Prior art keywords
- nitrogen
- vacuum
- vod
- content
- stainless steel
- 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.)
- Expired - Fee Related
Links
Landscapes
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention discloses a kind of nitrogen content control method for smelting stainless steel by vacuum oxygen decarburization device, this method is controlled to be nitrogen content greater than 1000ppm with the VOD initial condition, AOD terminal point carbon content is controlled to be 0.20~0.25%, and then in VOD vacuum-treat process, carry out decarburization, desulfurization charges into the operation of nitrogen, in the atmosphere adjusting stage, carry out the fine setting of nitrogen composition by bottom blowing nitrogen at last.Thereby in the time of can reaching VOD control endpoint carbon content<250ppm, VOD terminal point nitrogen content can be realized stable control flexibly in 300~900ppm scope, solved in the VOD vacuum metling low-carbon (LC) control nitrogen type stainless steel process problem of dark decarburization and control nitrogen contradiction, for exploitation provides the otherwise effective technique assurance with nitrogen for the economical stainless steel of joint nickel of nickel.Reduced simultaneously the consumption of this type of steel grade smelting process argon gas, anti-material etc. again, the consumption of having saved the chromium nitride alloy, 120 yuan/ton of ton smelting steel cost savings.
Description
Technical field
The present invention relates to the stainless steel smelting technology, special relevant with VOD vacuum oxygen decarburization refining techniques.
Background technology
Along with global stainless steel production capacity promotes, nickel resources day is becoming tight, and each big stainless steel plant, the world develops one after another with the nickel-saving type stainless steel of nitrogen for nickel, and wherein 00Cr19Ni10 (being 304L) is exactly one of most typical steel grade, from the big condition of production, this type of steel grade is smelted and is had certain difficulty at present.There is following defective when for example, the two-step process path smelts this type of steel grade:
(1) since stainless steel smelting with the molten iron of cheapness as main raw material, cause the initial carbon content of AOD higher (>3%), smelting cycle is long partially, so that rhythm of production is difficult to coupling, connects that to water the stove number on the low side;
(2) because endpoint carbon content requires<0.025%, and AOD decarburization task is all relatively heavy, the consumption of various media and anti-material is all than higher.
Relative two step method, three-step approach is smelted this type of steel grade can shorten the AOD smelting cycle, faster production rhythm, and can reduce various energy medium consumption (as Ar), realize that smelting cost reduces.But concerning VOD, smelt this type of steel grade and also have a unmanageable problem of terminal point nitrogen content, mainly be because:
(1) according to normal VOD vacuum metling technology, if require control endpoint carbon content<0.025%, then the VOD vacuum-treat finish nitrogen content must<200ppm;
(2) owing to the restriction of ladle bottom blowing gas permeable brick, VOD ladle bottom blowing nitrogen flow is less relatively, so that limited by bottom blowing nitrogen nitrogen pick-up speed, if nitrogen increased amount is excessive, then smelting cycle is longer relatively;
(3) owing to causing the serious temperature drop of molten steel, so VOD is limited by the amplitude of bottom blowing nitrogen nitrogen pick-up by a large amount of nitrogen nitrogen pick-up of bottom blowing meeting.
Summary of the invention
The objective of the invention is in order to solve the unmanageable problem of VOD smelting low carbon control nitrogen type stainless steel nitrogen content, a kind of nitrogen content control method for smelting stainless steel by vacuum oxygen decarburization device is provided, it can realize endpoint carbon content less than 0.025%, and nitrogen content can be realized stable control flexibly in 300~900ppm scope.
For achieving the above object, the present invention is based on stainless steel refining VOD control nitrogen process thermodynamics and dynamic analysis, and each processing parameter is to the research of VOD control nitrogen influence, by special control to the whole vacuum metling process of VOD, in conjunction with go to the bottom nitrogen blowing microalloying operation of atmosphere, form a kind of new VOD control nitrogen technical scheme, concrete technical measures and controlled step are as follows:
One, control VOD initial carbon of supplied materials molten steel and nitrogen content, requiring initial carbon is 0.20~0.25%, initial nitrogen is greater than 1000ppm.
Because VOD vacuum decarburization process is accompanied by denitrogenation, and denitride amount becomes certain proportional relation with decarburized amount, so be necessary suitably to control the initial carbon content of VOD supplied materials molten steel; In addition, it is on the low side to finish the molten steel nitrogen content for fear of the VOD vacuum-treat, and preceding operation argon oxygen decarburizing furnace AOD can take omnidistance nitrogen flushing to smelt, and handles the preceding initial nitrogen content of molten steel to improve VOD.By research and practice, control VOD initial carbon content is 0.20~0.25%, initial nitrogen content is greater than 1000ppm the best, this carbon, nitrogen content scope can satisfy the requirement of VOD normal processing, can reduce the loss of nitrogen in the vacuum oxygen decarburization process and hitting of terminal point nitrogen content to greatest extent again.
Two, in VOD vacuum metling process, should follow following steps and requirement:
(1): the oxygen decarburization stage, after the VOD vacuum-treat begins, vacuum oxygen decarburization when vacuum tightness reaches 15 ~ 20kpa, CO content is to stop oxygen at 5 ~ 8% o'clock to the process waste gas.In order to solve low-carbon (LC) control nitrogen shaped steel kind VOD vacuum-treat stage decarburization and control nitrogen contradictory problems, at first reduce initial carbon content; Secondly should rationally control the vacuum oxygen decarburization time, i.e. control rationally stops oxygen constantly; According to decarburization thermodynamics and dynamic analysis, under guaranteeing that endpoint carbon content is less than 0.025% situation, the best oxygen that stops drops to 5 ~ 8% for the CO content in the waste gas constantly.
(2): free decarburization stage, CO, CO in the process waste gas
2Content was all reduced to 5% o'clock or dark vacuum strong mixing 10 ~ 12min can finish free decarburization.After the VOD oxygen blast stops, opening full pump and carry out the free decarburization of dark vacuum.Because the free decarburization of VOD is to carry out dark vacuum strong mixing to handle under no slag situation, so denitrogenation speed is relatively big; At this type of steel grade, should shorten free decarburization time as far as possible, reduce the loss of free decarburization stage nitrogen.CO, CO in the process waste gas
2Content was all reduced to 5% o'clock or dark vacuum strong mixing 10 ~ 12min can finish free decarburization.
(3): in the reinforced stage, before adding reductive agent ferrosilicon and slag charge, charge into nitrogen in the vacuum tank and press again.Nitrogen forms saturated nitrogen atmosphere after entering vacuum tank above molten steel surface, carry out the operation of strong mixing Argon simultaneously, and the promotion molten steel fully contacts with nitrogen, and the realization molten steel is inhaled nitrogen by a small margin.
(4): in the reduction and desulfurization stage, the reinforced end continues dark vacuum strong mixing reduction and desulfurization, keeps 5 ~ 10min.Because molten steel oxygen position, reduction back descends, and sweetening process takes dark vacuum strong mixing operation, so stage denitrogenation speed is also bigger.In order to reduce the loss of desulfurization stage nitrogen, should shorten dark vacuum reducing desulfurization time equally as far as possible, dark vacuum strong mixing desulfurization 5 ~ 10min can finish after promptly slag charge fully melted.
(5): the vacuum breaker stage, carry out vacuum breaker by nitrogen, continue to take the argon gas strong mixing in the vacuum breaker process, vacuum breaker finishes the back and continues to keep Argon to stir 3 ~ 5min, presses again as reinforced initial vacuum and realizes that molten steel inhales nitrogen by a small margin.
Three, bottom blowing nitrogen microalloying is handled
Finish back molten steel analysis of nitrogen content result according to the VOD vacuum-treat, under atmospheric condition, substitute chromium nitride and carry out the fine setting of nitrogen component, require under airtight environment, to carry out, to improve nitrogen pick-up efficient by bottom blowing nitrogen.
In the above-mentioned steps two (3) described, after free decarburization finishes,, vacuum tightness should be returned to behind 6 ~ 12kpa reinforced in order to prevent reinforced process splash.
In the above-mentioned steps three, the bottom blowing nitrogen flow is controlled at not serious exposed being advisable of molten steel, and the nitrogen flushing amount can be calculated according to the deviation of actual nitrogen content and target nitrogen content.
Nitrogen nitrogen pick-up coefficient is roughly 800~1000ppm/m in the above-mentioned steps three
3T).
The present invention makes it compared with prior art owing to adopted above technical scheme, has the following advantages and positively effect:
1. dark decarburization and control nitrogen contradictory problems that VOD vacuum metling low-carbon (LC) control nitrogen type stainless steel faces have been solved effectively, guaranteeing under the situation of VOD endpoint carbon content less than 250ppm that promptly VOD terminal point nitrogen content can be realized stable control flexibly in 300~900ppm scope.
2. after this control nitrogen method is implemented, reduced the consumption of this type of steel grade smelting process argon gas, anti-material etc., and the consumption of having saved the chromium nitride alloy, 120 yuan/ton of ton smelting steel cost savings.
Embodiment:
Embodiment 1:
Steel grade: 00Cr19Ni10;
1, VOD molten steel initial condition
(1) initial carbon content: 0.202%
(2) initial nitrogen content: 0.217%
(3) molten steel amount: 113t
2, VOD vacuum-treat actual achievement
(1) oxygen decarburization stops constantly: CO content 7.5% in the waste gas
(2) oxygen decarburization time: 24min
(3) free decarburization finish time: CO content 4.2% in the waste gas, CO
2Content 4.8%;
(4) free decarburization time: 9min
(5) reduction and desulfurization time: 6min
3, nitrogen microalloying actual achievement
(1) bottom blowing nitrogen: 40.6m
3
(2) nitrogen flushing flow, nitrogen flushing time: 90m
3/ h, 28min
4, composition actual achievement
(1) steel sample analysis
Element | C | Si | Mn | S | P | Cr | Ni | N |
The VOD vacuum is initial | 0.202 | 0.04 | 1.07 | 0.008 | 0.02 | 18.05 | 8.01 | 0.217 |
The VOD vacuum ends | 0.021 | 0.25 | 1.11 | 0.008 | 0.02 | 18.12 | 8.17 | 0.071 |
VOD handles end of a period | 0.02 | 0.38 | 1.10 | 0.009 | 0.02 | 18.03 | 8.04 | 0.061 |
Finished product | 0.019 | 0.37 | 1.11 | 0.008 | 0.021 | 18.19 | 8.19 | 0.068 |
(2) the gas sample is analyzed
Element | C | S | O | N |
The VOD vacuum ends | 0.015 | 0.008 | 0.007 | 0.043 |
VOD handles end of a period | 0.017 | 0.008 | 0.011 | 0.055 |
Finished product | 0.0196 | 0.008 | 0.0172 | 0.0582 |
Embodiment 2:
Steel grade: 00Cr19Ni10;
1, VOD molten steel initial condition
(1) initial carbon content: 0.258%
(2) initial nitrogen content: 0.093%
(3) molten steel amount: 110.2t;
2, VOD vacuum-treat actual achievement
(1) oxygen decarburization stops constantly: CO content 6.8% in the waste gas
(2) oxygen decarburization time: 26min
(3) free decarburization finish time: CO content 3.2% in the waste gas, CO
2Content 4.5%;
(4) free decarburization time: 8min
(5) reduction and desulfurization time: 8min
3, nitrogen microalloying actual achievement
(1) bottom blowing nitrogen: 25.4m
3
(2) nitrogen flushing flow, nitrogen flushing time: 90m
3/ h, 16min
4, composition actual achievement
(1) steel sample analysis
Element | C | Si | Mn | S | P | Cr | Ni | N |
The VOD vacuum is initial | 0.248 | 0.04 | 1.10 | 0.005 | 0.018 | 18.05 | 8.09 | 0.093 |
The VOD vacuum ends | 0.02 | 0.53 | 1.09 | 0.002 | 0.019 | 17.88 | 8.08 | 0.059 |
VOD handles end of a period | 0.028 | 0.51 | 1.12 | 0.002 | 0.018 | 18.17 | 8.20 | 0.062 |
Finished product | 0.022 | 0.47 | 1.10 | 0.002 | 0.02 | 18.19 | 8.07 | 0.060 |
(2) the gas sample is analyzed
Element | C | S | O | N |
The VOD vacuum ends | 0.0166 | 0.002 | 0.0436 | 0.0555 |
VOD handles end of a period | 0.0156 | 0.001 | 0.0047 | 0.0556 |
Finished product | 0.016 | 0.002 | 0.0059 | 0.0584 |
Embodiment 3:
Steel grade: 00Cr19Ni10;
Molten steel amount: 118.4t
1, VOD molten steel initial condition
(1) initial carbon content: 0.228%
(2) initial nitrogen content: 0.115%
2, VOD vacuum-treat actual achievement
(1) oxygen decarburization stops constantly: CO content 8% in the waste gas
(2) oxygen decarburization time: 24min
(3) free decarburization finish time: CO content 2.8% in the waste gas, CO
2Content 4.2%;
(4) free decarburization time: 12min
(5) reduction and desulfurization time: 10min
3, nitrogen microalloying actual achievement
(1) bottom blowing nitrogen: 15m
3
(2) nitrogen flushing flow, nitrogen flushing time: 90m
3/ h, 11min
4, composition actual achievement
(1) steel sample analysis
Element | C | Si | Mn | S | P | Cr | Ni | N |
The VOD vacuum is initial | 0.228 | 0.05 | 1.18 | 0.006 | 0.021 | 17.89 | 8.03 | 0.115 |
The VOD vacuum ends | 0.02 | 0.51 | 1.11 | 0.003 | 0.02 | 17.83 | 8.08 | 0.056 |
VOD handles end of a period | 0.022 | 0.49 | 1.12 | 0.003 | 0.021 | 18.09 | 8.04 | 0.065 |
Finished product | 0.019 | 0.48 | 1.14 | 0.003 | 0.020 | 18.22 | 8.18 | 0.064 |
(2) the gas sample is analyzed
Element | C | S | O | N |
The VOD vacuum ends | 0.0196 | 0.003 | 0.0058 | 0.0510 |
VOD handles end of a period | 0.0210 | 0.003 | 0.0065 | 0.0624 |
Finished product | 0.0185 | 0.002 | 0.0062 | 0.0622 |
Embodiment 4:
Steel grade: 00Cr19Ni10;
1, VOD molten steel initial condition
(1) initial carbon content: 0.212%
(2) initial nitrogen content: 0.127%
(3) molten steel amount: 108t
2, VOD vacuum-treat actual achievement
(1) oxygen decarburization finish time: CO content 5% in the waste gas
(2) oxygen decarburization time: 26min
(3) free decarburization finish time: CO content 3.2% in the waste gas, CO
2Content 4.3%;
(4) free decarburization time: 12min
(5) reduction and desulfurization time: 8min
3, nitrogen microalloying actual achievement
(1) bottom blowing nitrogen: 22.5m
3
(2) nitrogen flushing flow, nitrogen flushing time: 90m
3/ h, 16min
4, composition actual achievement
(1) steel sample analysis
Element | C | Si | Mn | S | P | Cr | Ni | N |
The VOD vacuum is initial | 0.248 | 0.05 | 1.04 | 0.004 | 0.025 | 18.15 | 8.15 | 0.127 |
The VOD vacuum ends | 0.022 | 0.41 | 1.04 | 0.004 | 0.024 | 18.12 | 8.12 | 0.046 |
VOD handles end of a period | 0.022 | 0.38 | 1.05 | 0.003 | 0.025 | 18.13 | 8.10 | 0.056 |
Finished product | 0.023 | 0.39 | 1.03 | 0.003 | 0.025 | 18.10 | 8.13 | 0.054 |
(2) the gas sample is analyzed
Element | C | S | O | N |
The VOD vacuum ends | 0.0202 | 0.004 | 0.0059 | 0.0436 |
VOD handles end of a period | 0.0218 | 0.003 | 0.0067 | 0.0542 |
Finished product | 0.0220 | 0.002 | 0.0072 | 0.0532 |
Embodiment 5:
Steel grade: 00Cr19Ni10;
1, VOD molten steel initial condition
(1) initial carbon content: 0.243%
(2) initial nitrogen content: 0.126%
(3) molten steel amount: 109.5t;
2, VOD vacuum process control actual achievement
(1) oxygen decarburization stops constantly: CO content 8% in the waste gas
(2) oxygen decarburization time: 25min
(3) free decarburization finish time: CO content 4.6% in the waste gas, CO
2Content 5.0%;
(4) free decarburization time: 8min
(5) reduction and desulfurization time: 5min
3, nitrogen microalloying actual achievement
(1) bottom blowing nitrogen: 28m
3
(2) nitrogen flushing flow, nitrogen flushing time: 90m
3/ h, 18min
4, composition actual achievement
(1) steel sample analysis
Element | C | Si | Mn | S | P | Cr | Ni | N |
The VOD vacuum is initial | 0.243 | 0.04 | 1.14 | 0.004 | 0.023 | 18.15 | 8.03 | 0.126 |
The VOD vacuum ends | 0.019 | 0.45 | 1.12 | 0.003 | 0.022 | 17.88 | 8.04 | 0.042 |
VOD handles end of a period | 0.020 | 0.46 | 1.13 | 0.002 | 0.023 | 18.17 | 8.02 | 0.058 |
Finished product | 0.020 | 0.45 | 1.10 | 0.002 | 0.023 | 18.19 | 8.01 | 0.060 |
(2) the gas sample is analyzed
Element | C | S | O | N |
The VOD vacuum ends | 0.0170 | 0.003 | 0.0067 | 0.0400 |
VOD handles end of a period | 0.0185 | 0.002 | 0.0062 | 0.0564 |
Finished product | 0.0190 | 0.002 | 0.0058 | 0.0553 |
Claims (4)
1. nitrogen content control method for smelting stainless steel by vacuum oxygen decarburization device is characterized in that comprising:
Step 1: control VOD initial carbon of supplied materials molten steel and nitrogen content, initial carbon is 0.20~0.25%, initial nitrogen is greater than 1000ppm;
Step 2: VOD vacuum metling process
(1) the oxygen decarburization stage, CO content is to stop oxygen at 5 ~ 8% o'clock in the process waste gas;
(2) the free decarburization stage, CO, CO in the process waste gas
2Content was all reduced to 5% o'clock or dark vacuum strong mixing 8 ~ 12min can finish free decarburization;
(3) in the reinforced stage, add before reductive agent ferrosilicon and the slag charge, charge into nitrogen in the vacuum tank and press again, nitrogen forms saturated nitrogen atmosphere after entering vacuum tank above molten steel surface, carry out the operation of strong mixing Argon simultaneously, the promotion molten steel fully contacts with nitrogen, and the realization molten steel is inhaled nitrogen by a small margin;
(4) the reduction and desulfurization stage, 5 ~ 10min is kept in dark vacuum strong mixing;
(5) the vacuum breaker stage charges into the nitrogen vacuum breaker, and takes the argon gas strong mixing, and the multiple fully back of pressing continues to keep Argon to stir 3 ~ 5min;
Step 3: bottom blowing nitrogen microalloying is handled, and finishes back molten steel analysis of nitrogen content result according to the VOD vacuum-treat, carries out the fine setting of nitrogen component under atmospheric condition, in airtight environment.
2. nitrogen content control method for smelting stainless steel by vacuum oxygen decarburization device as claimed in claim 1 is characterized in that: step 2 returns to 6 ~ 12kpa with vacuum tightness in (3).
3. nitrogen content control method for smelting stainless steel by vacuum oxygen decarburization device as claimed in claim 2, it is characterized in that: the bottom blowing nitrogen flow is controlled at not serious exposed being advisable of molten steel in the step 3, and the nitrogen flushing amount can be calculated according to actual nitrogen content and target nitrogen content deviation.
4. nitrogen content control method for smelting stainless steel by vacuum oxygen decarburization device as claimed in claim 3 is characterized in that: nitrogen nitrogen pick-up coefficient is 800~1000ppm/m in the step 3
3T.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CNB2007100385292A CN100567512C (en) | 2007-03-27 | 2007-03-27 | A kind of nitrogen content control method for smelting stainless steel by vacuum oxygen decarburization device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CNB2007100385292A CN100567512C (en) | 2007-03-27 | 2007-03-27 | A kind of nitrogen content control method for smelting stainless steel by vacuum oxygen decarburization device |
Publications (2)
Publication Number | Publication Date |
---|---|
CN101275174A CN101275174A (en) | 2008-10-01 |
CN100567512C true CN100567512C (en) | 2009-12-09 |
Family
ID=39995032
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CNB2007100385292A Expired - Fee Related CN100567512C (en) | 2007-03-27 | 2007-03-27 | A kind of nitrogen content control method for smelting stainless steel by vacuum oxygen decarburization device |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN100567512C (en) |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102199688B (en) * | 2010-03-25 | 2013-02-06 | 宝山钢铁股份有限公司 | Method for efficiently refining ultra-pure ferritic stainless steel |
CN102251076B (en) * | 2010-05-21 | 2013-04-03 | 宝山钢铁股份有限公司 | RH vacuum refining method of ultra-low carbon stainless steel |
CN102312175B (en) * | 2011-07-01 | 2013-03-13 | 山西太钢不锈钢股份有限公司 | Method for manufacturing stainless steel plate used for thermonuclear fusion reactor |
CN107955857B (en) * | 2017-10-23 | 2019-10-18 | 邢台钢铁有限责任公司 | A kind of control nitrogen method during AOD smelting stainless steel |
CN108588338B (en) * | 2018-03-20 | 2019-05-03 | 北京科技大学 | A kind of VD furnace utilizes CO2The method for making steel denitrogenation |
CN108570535A (en) * | 2018-05-25 | 2018-09-25 | 河北工业职业技术学院 | The experimental facilities and method of nitrogen blowing alloying under the conditions of a kind of stainless-steel vacuum |
CN112126745A (en) * | 2020-09-27 | 2020-12-25 | 江油市长祥特殊钢制造有限公司 | Nitrogen increasing method for stainless steel |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1032974C (en) * | 1993-07-23 | 1996-10-09 | 大冶钢厂 | Method for smelting ultra-low carbon high silicon stainless steel |
JP2000160233A (en) * | 1998-11-25 | 2000-06-13 | Sumitomo Metal Ind Ltd | Method for desulfurize-refining stainless steel |
KR20020022275A (en) * | 2000-09-19 | 2002-03-27 | 이구택 | Method for refining the austenite stainless hot metal having high Cr |
KR20020040023A (en) * | 2000-11-23 | 2002-05-30 | 이구택 | A method for manufacturing high chromium stainless steel using exhausted gas analysis |
-
2007
- 2007-03-27 CN CNB2007100385292A patent/CN100567512C/en not_active Expired - Fee Related
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1032974C (en) * | 1993-07-23 | 1996-10-09 | 大冶钢厂 | Method for smelting ultra-low carbon high silicon stainless steel |
JP2000160233A (en) * | 1998-11-25 | 2000-06-13 | Sumitomo Metal Ind Ltd | Method for desulfurize-refining stainless steel |
KR20020022275A (en) * | 2000-09-19 | 2002-03-27 | 이구택 | Method for refining the austenite stainless hot metal having high Cr |
KR20020040023A (en) * | 2000-11-23 | 2002-05-30 | 이구택 | A method for manufacturing high chromium stainless steel using exhausted gas analysis |
Non-Patent Citations (1)
Title |
---|
超低碳焊条钢的VOD冶炼. 常海等.材料开发与应用,第19卷第2期. 2004 * |
Also Published As
Publication number | Publication date |
---|---|
CN101275174A (en) | 2008-10-01 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN100567512C (en) | A kind of nitrogen content control method for smelting stainless steel by vacuum oxygen decarburization device | |
CN109252008B (en) | Production method of low-carbon low-nitrogen ultra-low-sulfur steel | |
CN101768656B (en) | Method for refining ultra-low carbon ferritic stainless steel under vacuum | |
CN101168817B (en) | Method for increasing nitrogen content of nitrogen-containing clean steel | |
CN103898269A (en) | Ultralow sulfur steel quick smelting method | |
CN103627841A (en) | Control method for nitrogen content of molten steel of wear-resistant steel | |
CN109082496A (en) | A kind of method of whole process hypoxemia position smelting suprelow carbon steel | |
CN105603156A (en) | Production method for IF steel containing ultralow sulfur | |
CN105177427A (en) | Steel for 30CrMo gas cylinders and production method thereof | |
CN104004881A (en) | Method for controlling nitrogen content in process of producing aluminium deoxidation high-carbon steel | |
CN109112251A (en) | A kind of smelting process for quickly making white slag | |
CN101096723A (en) | Method for AOD whole melted iron directly smelting austenitic stainless steel | |
CN107904352A (en) | A kind of smelting process of high nitrogen martensitic stain less steel | |
CN103397146A (en) | Production method of pipeline steel | |
CN104946974A (en) | Ultra-low carbon baking hardened steel slab and method for controlling solid solution carbon content thereof | |
CN101962701B (en) | LT-CAS (Control Automatic System) double-station vacuum refining device and process method thereof | |
CN101671763A (en) | Method for increasing nitrogen for smelting high nitrogen stainless steel in argon oxygen decarburizing furnace | |
CN104988424A (en) | Method for smelting non-oriented silicon steel by using molten iron containing vanadium and titanium | |
CN101660022B (en) | Method for improving steel cleanness of stainless steel | |
CN103484599B (en) | Smelting method of high-manganese wear-resistant steel | |
CN104046923B (en) | The X80 pipe line steel smelted under half steel condition and production technique thereof | |
CN116179797A (en) | Converter sulfur-control smelting process | |
CN100447271C (en) | Method for smelting carbon dioxide corrosion resistant steel | |
CN102071284B (en) | Method for reducing water nozzle clogging of continuous casting machine | |
CN101391287A (en) | Method for controlling stable performance of steel slag in continuous casting tundish |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
C10 | Entry into substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
C14 | Grant of patent or utility model | ||
GR01 | Patent grant | ||
CF01 | Termination of patent right due to non-payment of annual fee | ||
CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20091209 Termination date: 20160327 |