CN105112617B - Cold-rolled orientation silicon steel high-temperature annealing process - Google Patents
Cold-rolled orientation silicon steel high-temperature annealing process Download PDFInfo
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- CN105112617B CN105112617B CN201510615886.5A CN201510615886A CN105112617B CN 105112617 B CN105112617 B CN 105112617B CN 201510615886 A CN201510615886 A CN 201510615886A CN 105112617 B CN105112617 B CN 105112617B
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Abstract
The present invention discloses a kind of cold-rolled orientation silicon steel high-temperature annealing process, which uses pure dry hydrogen atmosphere instead decomposed ammonia, and danger coefficient is reduced under the premise of final products performance is not influenced, and achievees the purpose that energy-saving；By coil of strip shove charge, table sealing adds outer cover, heat temperature raising, and be first passed through 8m before heating3The N of/h2Air in stove is emptied, in 8m3The N of/h2Furnace body is warming up to 570 DEG C under protective atmosphere, 6m is used instead after being warming up to 570 DEG C3Decomposed ammonia carry out 20~30h of protection, then be warming up to 650 DEG C and keep the temperature 10~15h；1130 DEG C -1200 DEG C generation secondary recrystallizations are raised to 15~20 DEG C/h speed after heat preservation；3m is used in power-off instead3The decomposed ammonia protection of/h is cooled down, and 6m is changed to again to less than 1000 DEG C3The N of/h2450 DEG C are cooled to come out of the stove.
Description
Technical field
Cold-rolled orientation silicon steel high-temperature annealing process of the present invention, and in particular to chemical technology field, mechanical manufacturing field, metal
The technical fields such as material science, metal heat treatmet.
Background technology
The production technology of Ji Jia cold-rolled orientation silicon steels factory of the current country is to roll into the silicon steel for coating magnesia in stove, is done
Start to be passed through 8~10m after good sealing3N2, by the O in stove2It is started to warm up after emptying, temperature is raised to 570 DEG C in 2~3h
~600 DEG C, 15~30h is kept the temperature, protective atmosphere at this time is 6m3Decomposed ammonia；Then 650 DEG C are warming up in 1h, heat preservation
10~20h, this process whole process protection atmosphere are 6m3Decomposed ammonia；Then 1130 DEG C~1200 DEG C are warming up to, the temperature rise period
It heats up by the speed of 15 DEG C~20 DEG C/h, protective atmosphere 5m3Decomposed ammonia, heat preservation 24 when reaching 1130 DEG C~1200 DEG C~
30h, protective atmosphere 3m3Pure dry hydrogen；It is exactly finally temperature-fall period, when dropping to below 1000 DEG C for 1130 DEG C~1200 DEG C,
Use 3m instead3Decomposed ammonia, cooling rate uses 6m instead for 60 DEG C/h or so when dropping to less than 10003N2Start to do protection gas
Body, cooling rate are controlled between 10 DEG C~40 DEG C, and coil of strip is come out of the stove when less than 450 DEG C.
Above-mentioned technique switches atmosphere in the temperature for reaching high heat preservation, uses pure dry hydrogen atmosphere instead and carries out protection heating.Due to
At high temperature using pure hydrogen there are certain danger, it may cause furnace body if hydrogen is impure with certain oxygen and blow out,
Pure hydrogen will be significantly larger than decomposed ammonia on production cost, and production cost is high.
Invention content
The invention overcomes the deficiencies of the prior art, and provides a kind of cold-rolled orientation silicon steel high-temperature annealing process, should
Technique uses pure dry hydrogen atmosphere instead decomposed ammonia, and danger coefficient is reduced under the premise of final products performance is not influenced, and reaches section
The purpose that can be lowered consumption.
In order to solve the above-mentioned technical problem, the technical solution adopted by the present invention is：Cold-rolled orientation silicon steel high-temperature annealing process,
Include the following steps：
The first step：Coil of strip shove charge is first cleaned table using pressure-air before shove charge, by the dust in snorkel or
Other impurities purgings are clean, and matching charging tray and charging basket are then selected according to the coil diameter size of coil of strip, divide three layers by coil of strip
It is put into stove；
Second step：Table seals, and liner is covered on the coil of strip installed, is made above the seal groove and table of liner lower end
Sealing ring coincide, on table carry bolt liner and table are linked together, then in the cooling water of table bottom
Recirculated water is passed through in pipe to ensure that the ring flange of table and inner cover will not high temperature deformation；
Third walks：Add outer cover, outside the liner being sealed plus outer cover, outer cover use heated by natural gas or electrically heated mode
It is heated, table uses electrical heating；
4th step：Heat temperature raising is first passed through 5-8m before heating3The N of/h2Air in stove is emptied and then added
Heat；
5th step：Minimum living thermophase, in 5-8m3The N of/h2Furnace body is warming up to 530-570 DEG C under protective atmosphere, works as liter
Temperature is to using 3-6m instead after 530-570 DEG C3The decomposed ammonia of/h carries out 20~30h of protection, then heats up under same atmosphere
To 600-650 DEG C and keep the temperature 10~20h；
6th step：High holding stage is raised to after 1130 DEG C -1200 DEG C simultaneously with 15~20 DEG C/h speed after minimum living temperature
With 3-6m3The decomposed ammonia of/h carries out 20-25h of protection, occurs secondary recrystallization in the process, and to the silicon steel in stove into
Row purified treatment（Remove the objectionable impurities such as N, S in silicon steel）；
7th step：Temperature-fall period, after height heat preservation, 3-6m is used in power-off instead3The decomposed ammonia protection of/h is cooled down,
It is changed to 3-6m again to less than 1000 DEG C3The N of/h2400-550 DEG C are cooled to come out of the stove.
Preferably, in the 5th step, the water of constitution in magnesia is removed in minimum living thermophase, control dew point of atmosphere exists
0 DEG C hereinafter, prevent FeO and Fe in surface film oxide2SiO4Content increase, it is bad to the bottom layer quality formed later.
Preferably, in the 6th step, in high holding stage, 1000 DEG C of formation bottoms are warming up to, control atmosphere dew at this time
For point no more than -15 DEG C, entire temperature-rise period uses 5m3The decomposed ammonia of/h starts to be converted to gas when being raised to 1130~1200 DEG C
Atmosphere dew point is less than -60 DEG C of decomposed ammonia, and control flow is 6m3/ h heat preservations carry out purification annealing for 24 hours, make the decomposed ammonia of discharge
Dew point is not more than -20 DEG C.
The present invention has an advantageous effect in that compared with prior art：It is of the invention compared with existing method, existing side
Method is that section uses pure hydrogen between height is kept the temperature, and since the activity of hydrogen is very high, is easily exploded using hydrogen at high temperature, this hair
It is bright then in high holding stage using decomposed ammonia, it is more stable for decomposed ammonia relative hydrogen, also compared with hydrogen on production cost
Gas is low, and the present invention can play the role of reducing the probability and production cost that accident occurs.
Specific embodiment
Application principle, effect and effect of the present invention, is explained by the way that mode is implemented as follows.
Embodiment one
The cold-rolled orientation silicon steel high annealing production technology of the present invention, includes the following steps：
1st, coil of strip shove charge is first cleaned table using pressure-air before shove charge, by the dust in snorkel or other
Impurities purging is clean, then selects suitable charging tray and charging basket through size according to the volume of coil of strip, and coil of strip point is put into stove for three layers.
2nd, table seals.Liner is covered on the coil of strip installed, is made close above the seal groove and table of liner lower end
Seal coincide, and liner and table is linked together with the bolt carried on table, then in the cooling water pipe of table bottom
Recirculated water is passed through to ensure that the ring flange of table and inner cover will not high temperature deformation.
3rd, add outer cover, outside the liner being sealed plus outer cover, outer cover are heated by the way of heated by natural gas, table
Use electrical heating.
4th, heat temperature raising is first passed through 8m before heating3The pure N of/h2Air in stove is emptied and then heated.
5th, minimum living thermophase, in 8m3The pure N of/h2Furnace body is quickly warming up to 570 DEG C under protective atmosphere, when being warming up to 570
Use 6m after DEG C instead3The decomposed ammonia of/h carries out protection 20h, is then rapidly heated under same atmosphere to 650 DEG C and kept the temperature
10h.The effect in this stage is to remove the water of constitution in magnesia, and control dew point of atmosphere is below 0 DEG C.Prevent surface film oxide
Middle FeO and Fe2SiO4Content increases, bad to the bottom layer quality formed later.
6th, it is secondary with 15~20 DEG C/h speed to be raised to 1130 DEG C -1200 DEG C generations after minimum living temperature slowly for high holding stage
Recrystallization.1000 DEG C of formation bottoms are warming up to, dew point of atmosphere are controlled to use 5m no more than the entire temperature-rise periods of -15 DEG C of at this time3/h
Decomposed ammonia, start to be converted to the decomposed ammonia that dew point of atmosphere is less than -60 DEG C when being raised to 1185 DEG C, control flow is 6m3/h
Heat preservation carries out purification annealing for 24 hours, and the decomposed ammonia dew point of discharge is made to be not more than -20 DEG C.
7th, temperature-fall period, after height heat preservation, 3m is used in power-off instead3The decomposed ammonia protection of/h is cooled down, to 1000 DEG C
It is changed to 6m again below3The N of/h2400 DEG C are cooled to come out of the stove.
Embodiment two
1st, coil of strip shove charge is first cleaned table using pressure-air before shove charge, by the dust in snorkel or other
Impurities purging is clean, then selects suitable charging tray and charging basket through size according to the volume of coil of strip, and coil of strip point is put into stove for three layers.
2nd, table seals, and liner is covered on the coil of strip installed, is made close above the seal groove and table of liner lower end
Seal coincide, and liner and table is linked together with the bolt carried on table, then in the cooling water pipe of table bottom
Recirculated water is passed through to ensure that the ring flange of table and inner cover will not high temperature deformation.
3rd, add outer cover, outside the liner being sealed plus outer cover, outer cover are heated by the way of heated by natural gas, table
Use electrical heating.
4th, heat temperature raising is first passed through 8m before heating3The pure N of/h2Air in stove is emptied and then heated.
5th, minimum living thermophase, in 8m3The pure N of/h2Furnace body is quickly warming up to 570 DEG C under protective atmosphere, when being warming up to 570
Use 6m after DEG C instead3The decomposed ammonia of/h carries out protection 30h, is then rapidly heated under same atmosphere to 650 DEG C and kept the temperature
10h.The effect in this stage is to remove the water of constitution in magnesia, and control dew point of atmosphere is below 0 DEG C.Prevent surface film oxide
Middle FeO and Fe2SiO4Content increases, bad to the bottom layer quality formed later.
6th, it is secondary with 15~20 DEG C/h speed to be raised to 1130 DEG C -1200 DEG C generations after minimum living temperature slowly for high holding stage
Recrystallization.1000 DEG C of formation bottoms are warming up to, controlling dew point of atmosphere at this time, entire temperature-rise period uses 5m no more than -15 DEG C3/h
Decomposed ammonia, start to be converted to the decomposed ammonia that dew point of atmosphere is less than -60 DEG C when being raised to 1185 DEG C, control flow is 6m3/h
Heat preservation 20h carries out purification annealing, and the decomposed ammonia dew point of discharge is made to be not more than -20 DEG C.
7th, temperature-fall period, after height heat preservation, 3m is used in power-off instead3The decomposed ammonia protection of/h is cooled down, to 1000 DEG C
It is changed to 6m again below3The N of/h2450 DEG C are cooled to come out of the stove.
Embodiment three
1st, coil of strip shove charge is first cleaned table using pressure-air before shove charge, by the dust in snorkel or other
Impurities purging is clean, then selects suitable charging tray and charging basket through size according to the volume of coil of strip, and coil of strip point is put into stove for three layers.
2nd, table seals, and liner is covered on the coil of strip installed, is made close above the seal groove and table of liner lower end
Seal coincide, and liner and table is linked together with the bolt carried on table, then in the cooling water pipe of table bottom
Recirculated water is passed through to ensure that the ring flange of table and inner cover will not high temperature deformation.
3rd, add outer cover, outside the liner being sealed plus outer cover, outer cover are heated by the way of heated by natural gas, table
Use electrical heating.
4th, heat temperature raising is first passed through 8m before heating3The pure N of/h2Air in stove is emptied and then heated.
5th, minimum living thermophase, in 8m3The pure N of/h2Furnace body is quickly warming up to 570 DEG C under protective atmosphere, when being warming up to 570
Use 6m after DEG C instead3The decomposed ammonia of/h carries out protection 30h, is then rapidly heated under same atmosphere to 650 DEG C and kept the temperature
15h.The effect in this stage is to remove the water of constitution in magnesia, and control dew point of atmosphere is below 0 DEG C.Prevent surface film oxide
Middle FeO and Fe2SiO4Content increases, bad to the bottom layer quality formed later.
6th, it is secondary with 15~20 DEG C/h speed to be raised to 1130 DEG C -1200 DEG C generations after minimum living temperature slowly for high holding stage
Recrystallization.1000 DEG C of formation bottoms are warming up to, dew point of atmosphere are controlled to be not more than -15 DEG C at this time.Entire temperature-rise period uses 5m3/h
Decomposed ammonia, start to be converted to the decomposed ammonia that dew point of atmosphere is less than -60 DEG C when being raised to 1170 DEG C, control flow is 6m3/h
Heat preservation carries out purification annealing for 24 hours, and the decomposed ammonia dew point of discharge is made to be not more than -20 DEG C.
7th, temperature-fall period, after height heat preservation, 3m is used in power-off instead3The decomposed ammonia protection of/h is cooled down, to 1000 DEG C
It is changed to 6m again below3The N of/h2500 DEG C are cooled to come out of the stove.
In conclusion cold-rolled orientation silicon steel high-temperature annealing process of the present invention, there is probability that reduction accident occurs and energy saving
The advantages of consumption reduction.
The present invention is explained in detail above in conjunction with embodiment, but the present invention is not limited to above-described embodiment, at this
In the knowledge that field those of ordinary skill has, various changes can also be made under the premise of present inventive concept is not departed from
Change.
Claims (1)
1. cold-rolled orientation silicon steel high-temperature annealing process, which is characterized in that include the following steps：
The first step：Coil of strip shove charge is first cleaned table using pressure-air before shove charge, by the dust in snorkel or other
Impurities purging is clean, and matching charging tray and charging basket are then selected according to the coil diameter size of coil of strip, and coil of strip point is put into for three layers
In stove；
Second step：Table seals, and liner is covered on the coil of strip installed, is made close above the seal groove and table of liner lower end
Seal coincide, and liner and table is linked together with the bolt carried on table, then in the cooling water pipe of table bottom
Recirculated water is passed through to ensure that the ring flange of table and inner cover will not high temperature deformation；
Third walks：Add outer cover, outside the liner being sealed plus outer cover, outer cover are carried out using heated by natural gas or electrically heated mode
Heating, table use electrical heating；
4th step：Heat temperature raising is first passed through 5-8m before heating3The N of/h2Air in stove is emptied and then heated；
5th step：Minimum living thermophase, in 5-8m3The N of/h2Furnace body is warming up to 530 DEG C -570 DEG C under protective atmosphere, works as heating
3-6m is used instead after to 530 DEG C-570 DEG C3The decomposed ammonia of/h carries out 20~30h of protection, then heats up under same atmosphere
To 600 DEG C -650 DEG C and keep the temperature 10~20h；The water of constitution in magnesia is removed in minimum living thermophase, control dew point of atmosphere exists
0 DEG C hereinafter, prevent FeO and Fe in surface film oxide2SiO4Content increase, it is bad to the bottom layer quality formed later；
6th step：High holding stage, be raised to after 1130 DEG C-1200 DEG C with 15~20 DEG C/h speed after minimum living temperature and with 3-
6m3The decomposed ammonia of/h carries out 20-25h of protection, and secondary recrystallization occurs in the process, and the silicon steel in stove is carried out net
Change is handled, that is, removes N, S objectionable impurities in silicon steel；In high holding stage, 1000 DEG C of formation bottoms are warming up to, control gas at this time
Atmosphere dew point is not more than-15 DEG C, and entire temperature-rise period uses 3-6m3The decomposed ammonia of/h starts to turn when being raised to 1130~1200 DEG C
The decomposed ammonia that dew point of atmosphere is less than-60 DEG C is changed to, control flow is 3-6m3/ h keeps the temperature 20-25h progress high temperature purifications and moves back
Fire makes the decomposed ammonia dew point of discharge be not more than -20 DEG C；
7th step：Temperature-fall period, after height heat preservation, 3-6m is used in power-off instead3The decomposed ammonia protection of/h is cooled down, to 1000
3-6m is changed to below DEG C again3The N of/h2400-550 DEG C are cooled to come out of the stove.
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| CN106435102B (en) * | 2016-08-17 | 2020-10-16 | 包头市威丰稀土电磁材料股份有限公司 | Tunnel type oriented silicon steel continuous high-temperature annealing process |
| CN109022701A (en) * | 2018-09-21 | 2018-12-18 | 蚌埠市双环电子集团股份有限公司 | A kind of soft magnetic materials annealing heat-treatment method |
| CN112593053A (en) * | 2020-12-14 | 2021-04-02 | 海安华诚新材料有限公司 | Oriented silicon steel high-temperature annealing process with low gas consumption optimization cost |
| CN113174468B (en) * | 2021-04-30 | 2023-03-24 | 福建省奥克兰光电科技有限公司 | Two-stage annealing process for high-temperature annealing and low-heat-preservation stage of oriented silicon steel bell-type furnace |
| CN113174469B (en) * | 2021-04-30 | 2023-03-24 | 福建省奥克兰光电科技有限公司 | Energy-saving process for high-temperature annealing and low-heat-preservation stage of oriented silicon steel bell-type furnace |
| CN113293280B (en) * | 2021-06-03 | 2022-06-17 | 包头威丰新材料有限公司 | Continuous high-temperature bell-type annealing furnace for oriented silicon steel and annealing process thereof |
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| US6451128B1 (en) * | 1997-06-27 | 2002-09-17 | Pohang Iron & Steel Co., Ltd. | Method for manufacturing high magnetic flux denshy grain oriented electrical steel sheet based on low temperature slab heating method |
| KR100514790B1 (en) * | 2000-12-19 | 2005-09-14 | 주식회사 포스코 | A method for manufacturing grain-oriented electrical steel sheet with superior magnetic property using the low temperature heating method |
| CN102021282A (en) * | 2009-09-21 | 2011-04-20 | 宝山钢铁股份有限公司 | Annealing separant for preparing grain-oriented silicon steel and using method thereof |
| CN102560236B (en) * | 2010-12-17 | 2013-07-31 | 鞍钢股份有限公司 | Preparation method of common oriented silicon steel |
| CN103667874A (en) * | 2013-05-20 | 2014-03-26 | 新万鑫（福建）精密薄板有限公司 | Production method for shortening furnace time of oriented silicon steel during high-temperature annealing period |
| CN104630619B (en) * | 2015-02-09 | 2016-09-21 | 武汉钢铁(集团)公司 | The high silicon steel of a kind of CSP production and preparation method |
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Denomination of invention: High-temperature annealing process of cold-rolled oriented silicone steel Effective date of registration: 20190926 Granted publication date: 20180612 Pledgee: China Postal Savings Bank Limited by Share Ltd Baotou branch Pledgor: Baotou Weifeng rare earth magnetic materials Limited by Share Ltd Registration number: Y2019150000006 |
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