CN114959194A - Cover type annealing process for hot-rolled ferritic stainless steel - Google Patents
Cover type annealing process for hot-rolled ferritic stainless steel Download PDFInfo
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- CN114959194A CN114959194A CN202210492903.0A CN202210492903A CN114959194A CN 114959194 A CN114959194 A CN 114959194A CN 202210492903 A CN202210492903 A CN 202210492903A CN 114959194 A CN114959194 A CN 114959194A
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- 238000000137 annealing Methods 0.000 title claims abstract description 53
- 238000000034 method Methods 0.000 title claims abstract description 34
- 229910001220 stainless steel Inorganic materials 0.000 title claims abstract description 27
- 239000001257 hydrogen Substances 0.000 claims abstract description 51
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 51
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 49
- 238000001816 cooling Methods 0.000 claims abstract description 37
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 35
- 239000010959 steel Substances 0.000 claims abstract description 35
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 28
- 238000010438 heat treatment Methods 0.000 claims abstract description 21
- 238000010926 purge Methods 0.000 claims abstract description 20
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 14
- 238000010583 slow cooling Methods 0.000 claims abstract description 12
- 229910000734 martensite Inorganic materials 0.000 claims abstract description 10
- 238000012360 testing method Methods 0.000 claims abstract description 9
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 4
- 239000001301 oxygen Substances 0.000 claims abstract description 4
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 4
- 238000004321 preservation Methods 0.000 claims description 9
- 239000000203 mixture Substances 0.000 claims description 5
- 239000010935 stainless steel Substances 0.000 claims description 4
- 229910000859 α-Fe Inorganic materials 0.000 claims description 4
- 238000007599 discharging Methods 0.000 claims description 3
- 239000012535 impurity Substances 0.000 claims description 2
- 238000012545 processing Methods 0.000 abstract description 3
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 206010037544 Purging Diseases 0.000 description 14
- 230000000052 comparative effect Effects 0.000 description 13
- 238000005554 pickling Methods 0.000 description 9
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- 230000001603 reducing effect Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 239000002253 acid Substances 0.000 description 3
- 230000004580 weight loss Effects 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000005098 hot rolling Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 239000010965 430 stainless steel Substances 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000001186 cumulative effect Effects 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000005338 heat storage Methods 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000010079 rubber tapping Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
- C21D9/54—Furnaces for treating strips or wire
- C21D9/663—Bell-type furnaces
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Sheet Steel (AREA)
Abstract
The invention discloses a bell-type annealing process for hot-rolled ferritic stainless steel, which is characterized by comprising the following steps of: the method comprises the following steps: 1) and (3) loading rolls: stacking the steel coils on a furnace platform, fastening an inner cover, starting the seal test of a hydrogen valve of the furnace platform, locking the inner cover, performing the cold seal test of the furnace platform, finally starting the nitrogen replacement in the furnace, injecting 50-70Nm 3 Drives off the air in the furnace and finally the oxygen volume content in the furnace<1 percent; 2) setting a heating cover and igniting; 3) annealing; 4) hydrogen purging; 5) slowly cooling; 6) and (3) rapid cooling: hanging away from the heating cover, replacing the cooling cover, rapidly cooling the temperature in the furnace to 340-. The invention strictly controls the cooling rate in the slow cooling stage, and the martensite structure is fully decomposed, thereby being more beneficial to subsequent processing.
Description
Technical Field
The invention belongs to the technical field of stainless steel, and particularly relates to a bell-type annealing process for hot-rolled ferritic stainless steel.
Background
The traditional ferritic stainless steel (such as 430) has high carbon content, a certain proportion of high-temperature austenite phase region exists in the hot rolling process, a certain proportion of martensite phase exists in the hot-rolled strip steel, and carbides in the hot-rolled steel are distributed in a band shape, so that the processing performance and the corrosion resistance of the material are influenced. Therefore, the traditional ferritic stainless steel needs to enter a bell-type furnace for bell-type annealing treatment, so that martensite is decomposed into ferrite and carbide, and the carbide in the ferrite phase is uniformly dispersed and distributed, thereby achieving the purposes of softening the material and improving the corrosion resistance.
The hot-rolled stainless steel all-hydrogen hood-type annealing furnace comprises a furnace platform, an inner cover, a heating cover, a cooling cover, a valve station, a corresponding control system and the like, wherein the main annealing process comprises the steps of placing 3-4 steel coils on the furnace platform in a stacking mode, buckling the inner cover, performing sealing test and initial purging, buckling the heating cover, performing automatic ignition of the heating cover with two layers of 12 gas burners, transmitting heat to an inner cover wall through radiation by firepower of the burners, transmitting the heat of the inner cover wall to the steel coils mainly through convection heat transfer by using a protective atmosphere in the furnace, and achieving annealing operation of the steel coils.
During the period, the hydrogen in the furnace is swept in different stages according to different process requirements, the steel coil enters a cooling stage with a cooling cover after the temperature rise and the heat preservation are finished, nitrogen replacement is carried out after the set tapping temperature is reached, then the steel coil is hung away from the cooling cover and the inner cover, and the steel coil enters a pickling line for pickling and descaling after being cooled for a period of time outside the furnace.
The bell-type furnace is a periodic heat treatment furnace, and compared with a continuous heat treatment furnace, the annealing period of the bell-type furnace is much longer. In the conventional cap annealing process of hot-rolled 430 stainless steel, there are the following problems: the whole annealing period from the steel coil charging to the steel coil discharging is long; the use of hydrogen is increased by large-flow hydrogen purging in the annealing link, and simultaneously, due to the strong reducing effect of the hydrogen, the structure of oxide skin on the surface of the hot-rolled strip steel is changed, and the change of the structure of the oxide skin on the section is inconsistent due to the coil-shaped factor of the steel coil, so that the difficulty is increased for the subsequent acid washing treatment; the local over-temperature generated in the annealing process and the cooling rate control in the slow cooling stage cause the head and tail performance difference of the steel coil.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a cover annealing process for hot-rolled ferritic stainless steel, which is beneficial to fully softening a steel coil, has stable steel coil performance and greatly reduces the average hydrogen consumption per ton of steel.
The technical scheme adopted by the invention for solving the technical problems is as follows: a bell-type annealing process for hot-rolled ferritic stainless steel is characterized in that: the method comprises the following steps:
1) and (3) loading rolls: stacking the steel coils on a furnace platform, fastening an inner cover, starting the seal test of a hydrogen valve of the furnace platform, locking the inner cover, performing the cold seal test of the furnace platform, finally starting the nitrogen replacement in the furnace, injecting 50-70Nm 3 Drives off the air in the furnace and finally the oxygen volume content in the furnace<1％；
2) Setting a heating cover and igniting: starting ignition after the heating cover is buckled and the hearth is swept, and injecting 10-20Nm into the furnace during the period 3 Replacing nitrogen with hydrogen;
3) annealing: the annealing temperature is 830-870 ℃, and then the temperature of the platform is maintained for 16-30 h;
4) hydrogen purging: hydrogen is again injected in the annealing process for 10-20Nm 3 ；
5) And (3) slow cooling: after the heat preservation is finished, slowly cooling the mixture with the heating cover, and controlling the temperature to be below 760 ℃ at a cooling rate of less than 30 ℃/h;
6) and (3) rapid cooling: hanging away from the heating cover, replacing the cooling cover, rapidly cooling the temperature in the furnace to 340-.
Preferably, in the step 4),the purging of the hydrogen is started from the stage of entering the heat preservation, and the purging flow is set to be 10-15Nm 3 And/h, purging for 30-90min, so that the hydrogen is injected in a staggered manner with the hydrogen replacement in the step 2), the purpose is to keep certain hydrogen purity in the temperature rising and heat preservation stages, the conventional process is to continuously inject the hydrogen for a long time, because of the relation of pressure in the furnace and the like, the more the hydrogen is injected, the more the hydrogen is discharged out of the furnace, and the hydrogen can be discharged out besides the water vapor generated by the reaction. And a small amount of injection is staggered, abnormal discharge can be reduced, reaction is reduced, a certain amount of hydrogen is kept in the furnace, the effect of convection heat transfer is enhanced, hydrogen and water vapor in the furnace can reach a balance, particularly in the heat preservation section, the temperature rise section does not exhaust due to high furnace pressure, the hydrogen concentration in the furnace is reduced, and the heat conduction effect of hydrogen is enhanced. The lower hydrogen makes the structure of the oxide skin on the surface of the steel coil not obviously different, thereby reducing the difficulty of hot pickling and reducing the increase of heat loss caused by excessive waste gas emission.
Preferably, the area content of the martensite structure after the ferritic stainless steel is subjected to the cover annealing is controlled to be less than or equal to 0.1%. The temperature is controlled to be cooled to be lower than 760 ℃ at the cooling rate of less than 30 ℃/h, and the martensite structure generated by the fast cooling after the ferritic stainless steel is subjected to the cover annealing is eliminated.
Preferably, the ferritic stainless steel comprises the following components in percentage by mass: c is less than or equal to 0.12 percent, Si is less than or equal to 1.0 percent, Mn is less than or equal to 1.0 percent, P is less than or equal to 0.04 percent, S is less than or equal to 0.03 percent, Cr is 16.00 to 18.00 percent, and the balance is Fe and inevitable impurities.
Preferably, the yield strength of the ferritic stainless steel after the cover annealing is 260-330 MPa, the tensile strength is 440-520 MPa, the elongation is 26-33%, and the hardness is 135-150 HV.
Preferably, the yield strength and elongation of the ferritic stainless steel after the cap annealing are controlled within 5% of the variation between the head and the tail.
Compared with the prior art, the invention has the advantages that:
1) the hydrogen is used in the amount of only 20-40Nm 3 Furnace, average ton steel hydrogen consumption only about 0.4Nm 3 T, about 3.2Nm more conventional 3 The consumption per ton is reduced greatlyThe hydrogen use cost is saved, and the yield of 20 ten thousand tons of annealing per year can save more than 170 ten thousand yuan of hydrogen cost.
2) The invention only adopts a small amount of hydrogen to enter the furnace to weaken the strong reducibility of the steel coil iron scale, and fully utilizes the effect of strong heat conductivity, thereby reducing the change of the surface iron scale structure of the hot rolled steel coil and further reducing the load of subsequent hot pickling.
3) The cooling rate of less than 30 ℃/h is strictly controlled in the slow cooling stage, the reason is that local high temperature of the outer ring of the steel coil in the annealing process is easy to generate martensite structure in the subsequent rapid cooling process, the slow cooling is realized by controlling the cooling rate of less than 30 ℃/h, the slow cooling stage is combined with the cooling rate burner to continuously adopt small fire control, the conventional process extinguishes the burner of the heating cover after the heat preservation is finished, and when the heat storage capacity of the heating cover is poor, the temperature is rapidly reduced, so that the martensite structure cannot be fully decomposed, the material is not fully softened, and the subsequent processing is not facilitated.
4) The temperature in the steel coil is quickly cooled to 340-350 ℃, then nitrogen replacement is carried out, the higher temperature of the blowing-out furnace is set, the annealing period is greatly shortened, the final steel coil discharging temperature is lower than 300 ℃ after the final nitrogen replacement blowing, and the secondary oxidation of the surface of the steel coil is also avoided.
5) Compared with the conventional process, the acid pickling speed of the ferritic stainless steel subjected to cover annealing can be improved by 0.5-2mpm under the same condition.
6) The process adopted by the invention has obvious compression in the time of the temperature rise stage and the time of the rapid cooling stage, and can reduce the whole annealing period by 3-4.5h compared with the conventional process.
Drawings
FIG. 1 is a photograph (magnified 100 times) of a metallographic structure of a sample of example 1 of the present invention.
FIG. 2 is a photograph (magnified 100 times) of a metallographic structure of comparative example 3 of the present invention.
Detailed Description
The invention is described in further detail below with reference to the accompanying examples.
The present invention provides 3 examples and 3 comparative examples, which are selected from SUS430 smelted in the same furnace, and hot-rolled coils after casting and hot rolling, the compositions of which are shown in table 1, in order to ensure comparability.
The embodiment adopts the annealing process of the invention, and the preparation steps are as follows:
1) and (3) loading rolls: stacking 4 steel coils on a furnace platform, fastening an inner cover, starting the seal test of a hydrogen valve on the furnace platform, locking the inner cover, performing the cold seal test on the furnace platform, starting the nitrogen replacement in the furnace, and injecting 50-70Nm 3 Drives off the air in the furnace and finally the oxygen volume content in the furnace<1％；
2) Setting a heating cover and igniting: starting ignition after the heating cover is buckled and the hearth is swept, and injecting 10-20Nm into the furnace during the period 3 Replacing nitrogen with hydrogen; the heat conductivity coefficient of the hydrogen is 7 times that of the nitrogen, and the strong heat conductivity characteristic of the hydrogen is fully utilized to achieve the effect of shortening the annealing period.
3) Annealing: the annealing temperature is 830-870 ℃, and then the temperature of the platform is maintained for 16-30 h;
4) hydrogen purging: hydrogen is again injected in the annealing process for 10-20Nm 3 Setting purge flow 10-15Nm 3 H, purging for 30-90 min;
5) and (3) slow cooling: after the heat preservation is finished, slowly cooling the mixture with the heating cover, and controlling the temperature to be below 760 ℃ at a cooling rate of less than 30 ℃/h;
6) and (3) rapid cooling: and (3) hanging away the heating cover, replacing the cooling cover, cooling the temperature in the furnace to 340-.
Comparative example 1 differs from example 1 in that: the hydrogen purging stage adopted 30Nm 3 /h×1h+20Nm 3 /h×3h+10Nm 3 The furnace purging is carried out by setting the hydrogen flow rate of/h multiplied by 10h, and the cumulative hydrogen purging amount is about 190Nm 3 。
Comparative example 2 differs from example 2 in that: the rapid cooling stage, nitrogen displacement temperature 300 ℃.
Comparative example 3 differs from example 3 in that: and a slow cooling stage, wherein the cooling rate is 50 ℃/h.
The obtained examples and comparative examples were subjected to performance tests, and specific data are shown in table 3.
The data of example 1 and comparative example 1 show that under the same hood-type annealing process, the difference of the hydrogen amount input during the annealing process has stronger correlation with the weight loss rate of removing the oxide scale, and the weight loss rate of the hydrogen amount is larger than that of the hydrogen amount. The high weight loss rate means that the pickling rate of the 430 hot coil after hood annealing under the same pickling condition is high, the productivity is high, the pickling rate is also verified in the mass production of a production line, the speed can be increased by 0.5-2mpm, the strong heat conductivity of hydrogen is fully utilized in different hydrogen input time periods, and the mechanical properties of the strip steel under different hydrogen purging amounts are similar and have no obvious difference.
The data of the example 2 and the comparative example 2 show that the improvement of the purging temperature before the steel coil is discharged has no obvious difference on the mechanical property and the acid pickling property of the steel coil, and the improvement of the purging temperature before the steel coil is discharged can effectively shorten the hood type annealing period.
Generally, the outer ring of the steel coil in the cover annealing has a temperature higher than a target temperature, and the higher the annealing temperature is, the higher the risk of high temperature of the outer ring is. Therefore, slow cooling measures must be taken in the slow cooling section, otherwise, the martensite structure in the strip steel is precipitated due to the too fast cooling in the high temperature region, and the mechanical property of the material is further influenced, and the data of the example 3 and the comparative example 3 fully illustrate the influence relation of the cooling rate of the slow cooling section. FIG. 1 is a photograph of a metallographic structure of a sample of example 1 of the present invention, which shows a uniform ferrite structure after annealing; FIG. 2 is a photograph of a metallographic structure of comparative example 3 of the present invention, in which a small amount of precipitation of a martensite structure was observed.
TABLE 1 chemical composition/wt% of hot-rolled stainless steel coil used in examples and comparative examples
| C | Si | Mn | P | S | Cr | Fe |
| 0.034 | 0.28 | 0.31 | 0.027 | 0.002 | 16.2 | Balance of |
Table 2 control of key process parameters for example and comparative batch annealing process
TABLE 3 Performance and head-to-tail deviation of examples, comparative examples
Claims (6)
1. A bell-type annealing process for hot-rolled ferritic stainless steel is characterized in that: the method comprises the following steps:
1) and (3) loading rolls: stacking the steel coils on the furnace platform, fastening the inner cover, starting the seal test of the hydrogen valve on the furnace platform, locking the inner cover, testing the cold seal of the furnace platform, and finallyStarting nitrogen replacement in the furnace, injecting 50-70Nm 3 Drives off the air in the furnace and finally the oxygen volume content in the furnace<1％；
2) Setting a heating cover and igniting: starting ignition after the heating cover is buckled and the hearth is swept, and injecting 10-20Nm into the furnace during the period 3 Replacing nitrogen with hydrogen;
3) annealing: the annealing temperature is 830-870 ℃, and then the temperature is maintained for 16-30h on the temperature platform;
4) hydrogen purging: hydrogen is again injected in the annealing process for 10-20Nm 3 ；
5) And (3) slow cooling: after the heat preservation is finished, slowly cooling the mixture with the heating cover, and controlling the temperature to be below 760 ℃ at a cooling rate of less than 30 ℃/h;
6) and (3) quick cooling: and (3) hanging away the heating hood, replacing the cooling hood, rapidly cooling the temperature in the furnace to 340-350 ℃, then performing nitrogen replacement, completely replacing hydrogen in the furnace by nitrogen, finally hanging away the cooling hood and the inner hood, and discharging the steel coil in the furnace out of the furnace.
2. The bell annealing process of hot rolled ferritic stainless steel according to claim 1, characterized in that: in the step 4), the purging of the hydrogen is started from the stage of entering the heat preservation, and the purging flow is set to be 10-15Nm 3 And h, purging for 30-90 min.
3. The bell annealing process of hot rolled ferritic stainless steel according to claim 1, characterized in that: the martensite structure area content of the ferritic stainless steel after the cover annealing is controlled to be less than or equal to 0.1 percent.
4. The bell annealing process of hot rolled ferritic stainless steel according to claim 1, characterized in that: the ferrite stainless steel comprises the following components in percentage by mass: c is less than or equal to 0.12 percent, Si is less than or equal to 1.0 percent, Mn is less than or equal to 1.0 percent, P is less than or equal to 0.04 percent, S is less than or equal to 0.03 percent, Cr is 16.00 to 18.00 percent, and the balance is Fe and inevitable impurities.
5. The bell annealing process of hot rolled ferritic stainless steel according to any of claims 1 to 4 characterized in that: the yield strength of the ferritic stainless steel after the cover annealing is 260-330 MPa, the tensile strength is 440-520 MPa, the elongation is 26-33%, and the hardness is 135-150 HV.
6. The bell annealing process of hot rolled ferritic stainless steel according to claim 5, characterized in that: the deviation of the yield strength and the elongation percentage of the ferritic stainless steel after the cover annealing at the head and the tail is controlled within 5 percent.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4571273A (en) * | 1983-07-05 | 1986-02-18 | Ebner-Industrieofenbau Ing. Josef Ebner Kg | Process of heating and cooling charges in batch-process industrial furnaces |
| CN101760606A (en) * | 2008-12-26 | 2010-06-30 | 宁波宝新不锈钢有限公司 | Control method of protective atmosphere of stainless steel cover type annealing furnace |
| CN102586580A (en) * | 2012-03-12 | 2012-07-18 | 溧阳市宏大机械设备有限公司 | Bell-type furnace annealing process for BSYE-N steel belt |
| CN110331261A (en) * | 2019-08-20 | 2019-10-15 | 山西太钢不锈钢股份有限公司 | Think gauge low chrome ferritic stainless steel hot rolling curtain cover annealing method |
| CN113430339A (en) * | 2021-06-04 | 2021-09-24 | 唐山钢铁集团有限责任公司 | Control method of protective atmosphere of bell-type annealing furnace |
| CN114045380A (en) * | 2021-11-09 | 2022-02-15 | 山西太钢不锈钢股份有限公司 | Control method for annealing stamp of 400 series stainless steel bell-type furnace |
-
2022
- 2022-05-07 CN CN202210492903.0A patent/CN114959194A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4571273A (en) * | 1983-07-05 | 1986-02-18 | Ebner-Industrieofenbau Ing. Josef Ebner Kg | Process of heating and cooling charges in batch-process industrial furnaces |
| CN101760606A (en) * | 2008-12-26 | 2010-06-30 | 宁波宝新不锈钢有限公司 | Control method of protective atmosphere of stainless steel cover type annealing furnace |
| CN102586580A (en) * | 2012-03-12 | 2012-07-18 | 溧阳市宏大机械设备有限公司 | Bell-type furnace annealing process for BSYE-N steel belt |
| CN110331261A (en) * | 2019-08-20 | 2019-10-15 | 山西太钢不锈钢股份有限公司 | Think gauge low chrome ferritic stainless steel hot rolling curtain cover annealing method |
| CN113430339A (en) * | 2021-06-04 | 2021-09-24 | 唐山钢铁集团有限责任公司 | Control method of protective atmosphere of bell-type annealing furnace |
| CN114045380A (en) * | 2021-11-09 | 2022-02-15 | 山西太钢不锈钢股份有限公司 | Control method for annealing stamp of 400 series stainless steel bell-type furnace |
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