CN109628716A - High-performance tinplate production technology - Google Patents
High-performance tinplate production technology Download PDFInfo
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- CN109628716A CN109628716A CN201811636326.8A CN201811636326A CN109628716A CN 109628716 A CN109628716 A CN 109628716A CN 201811636326 A CN201811636326 A CN 201811636326A CN 109628716 A CN109628716 A CN 109628716A
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- Prior art keywords
- rolling
- degree
- temperature
- performance
- tinplate
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Classifications
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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
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
-
- 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
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0236—Cold rolling
-
- 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
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
- C21D8/0273—Final recrystallisation annealing
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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 kind of high-performance tinplate production technologies, are prepared using secondary cold-rolling ferrostan technique, wherein 1): when sorting, selecting SPHC low carbon steel plate, the hardness of hot rolling is in the range of T2.5, and carbon content is between 3-5；2): after pickling, when first time cold rolling, the deflection of first time is controlled, according to the requirement of deflection, the control of secondary cold rolling surplus within ± 1 UM of 14 UM, to guarantee the abundance of the drafts of secondary cold-rolling；3): when degreasing, guaranteeing that surface cleaning is clean, when bulk-breaking, by coil diameter control within 1.4 meters, volume size is consistent；4): strictly managing temperature when bell-type annealing, carry out secondary rolling in time.Present invention process is unique, and the tinplate intensity produced is good, and hardness is uniform, and crystallizes uniformly, and ductility is good, and version type is smooth, and being conducive to user reduces product thickness, reduces cost, in tinplate industry, has huge economic value, is worthy to be popularized.
Description
Technical field
The present invention relates to a kind of high-performance tinplate production technologies.
Background technique
Tinplate is huge with measuring in the industry, in the prior art, when meeting high hardness, typically only by
The method for increasing thickness achieves the goal, if can be reduced thickness, but has both high rigidity, can substantially reduce cost, people are always
It is dedicated to obtaining such improvement.
Summary of the invention
Technical problem to be solved by the invention is to provide the low thickness, high hard that a kind of finished product hardness can reach DR7-DR8
The high-performance tinplate production technology of degree, high extensibility.
The present invention is achieved through the following technical solutions:
High-performance tinplate production technology is prepared using secondary cold-rolling ferrostan technique, wherein
1): when sorting, selecting SPHC low carbon steel plate, the hardness of hot rolling is in the range of T2.5, and carbon content is between 3-5；Hair
Bright people passes through multiple experiment, and discovery can only select the raw material of T2.5 hardness just can make DR7-DR8 according to the production technology
High performance plate, above or below T2.5, the product worked it out can be partially soft, or partially hard；Why select carbon content in 3-5
Between, it is because carbon content range determines that finished material comes out later hardness range, this range is optimal.Preferably, choosing
When material, the steel plate with a thickness of 2.75mm is selected.
2): after pickling, when first time cold rolling, the deflection of first time is controlled, according to the requirement of deflection,
Secondary cold rolling surplus is controlled in 14UM ± 1UM, to guarantee the abundance of the drafts of secondary cold-rolling；If drafts is insufficient, firmly
Degree can not reach requirement.
3): when degreasing, guarantee that surface cleaning is clean, when bulk-breaking, by coil diameter control within 1.4 meters, volume size
Unanimously；Bell-type annealing Shi Jinlu in this way is put uniformly, and being heated will be uniform.
4): specific as follows when bell-type annealing:
(a) after in-furnace temperature reaches 400 degree, control rate of warming is 30-40 degree/hour, and temperature is added to from 400 degree
580 degree；In annealing, this is step key, and in order to guarantee hardness, the speed of heating determines the size of the thermal coefficient of steel, in steel
Carbon content and alloy amount be affected to heat transfer, heating speed has to slowly, avoid internal-external temperature difference excessive, and causes tissue
With the unevenness of performance, this section is exactly the stage of strip tissue crystals, and is controlled and can be protected in this stepwise heating speed
It is uniform to demonstrate,prove strip tissue crystals, guarantees that hardness is high, through overtesting, it is found that this temperature range and heating speed are most suitable.As
It is preferred that control rate of warming is 30-40 degree/hour after in-furnace temperature reaches 400 degree.
(b) when temperature reaches 580 degree, start to keep the temperature, soaking time is 14-16 hours；14-16 hours soaking times
The temperature of volume temperature is controlled at 580 degree, thermally equivalent state would be to the heated of volume in this way, to guarantee that crystal grain is equal in strip
It is even, this important function is played to the determination of hardness, moreover it is possible to guarantee the flexibility of finished product.Preferably, soaking time is 15 hours.
(c) Temperature fall after keeping the temperature, in Temperature fall to after 530 degree, mentioning heating mantles, the air-cooled and hot blow of progress,
At this moment the oil and gas and water in inner cover is driven away using protective gas, after air-cooled to 280 degree, then carry out water cooling to can just go out after 80 degree
Furnace；
(d) when falling to a certain temperature wait roll up temperature, milling train secondary cold-rolling is sent immediately, and the pumping of cold-rolling equipment is regulated in rolling
The position of roller guarantees that version type is smooth.Preferably, sending milling train secondary cold-rolling when rolling up temperature drop to 50 degree or less.Preferably,
When second of cold rolling, controlled rolling passage is 2 times, and with the rolling of uniform speed, mill speed is 750-800 per minute
Rice.Such product, hardness is up to standard and hardness is uniform, and allowance control is good, while guaranteeing hardness, because crystallization is equal
Even, the flexibility of material also can guarantee.
Preferably, process flow in the bell type annealing furnace are as follows: coil of strip shove charge → placement inner cover → locking inner cover → cold
State leakage check vacuumizes → heating mantles placement, igniting → nitrogen charging hydrogen shield → heat preservation → Thermal Sealing inspection → air cooling
→ water cooling → finally vacuumizing → locks release → inner cover and removes, comes out of the stove
More preferably, annealing medium: natural gas, Annealing Protection gas: 75% hydrogen, 25% nitrogen.
The beneficial effects of the present invention are:
High-performance tinplate production technology of the invention, technique are unique, by the improvement to entire technique, the horse produced
Mouth iron intensity is good, and hardness is uniform, and version type is smooth, can achieve in the case where plate is very thin, the effect that hardness is very big, and crystallizes
Uniformly, ductility is good, is ideal packaging material for food and the favorite packaging material for food of middle east, and product
Various performances can reach client and preferably require.The plate that the present invention obtains is only 0.13MM- in finished product thickness
When 0.5MM, hardness can reach DR7-DR8, be pervious technique have no idea realize, be conducive to user reduce product thickness,
Cost is reduced, in tinplate industry, has huge economic value, is worthy to be popularized.
Detailed description of the invention
The present invention is described in detail by following specific embodiments and drawings for ease of explanation,.
Fig. 1 is the tension test curve graph of the finished product one of present invention process preparation；
Fig. 2 is the tension test curve graph of the finished product two of present invention process preparation.
Specific embodiment
High-performance tinplate production technology, is prepared using secondary cold-rolling ferrostan technique, and finished product hardness can reach
DR7-DR8, wherein
1): when sorting, selecting SPHC low carbon steel plate, the hardness of hot rolling is in the range of T2.5, and carbon content is between 3-5；Hair
Bright people passes through multiple experiment, and discovery can only select the raw material of T2.5 hardness just can make DR7-DR8 according to the production technology
High performance plate, above or below T2.5, the product worked it out can be partially soft, or partially hard；Why select carbon content in 3-5
Between, it is because carbon content range determines that finished material comes out later hardness range, this range is optimal.When sorting, selection
With a thickness of the steel plate of 2.75mm.
2): after pickling, when first time cold rolling, the deflection of first time is controlled, according to the requirement of deflection,
Secondary cold rolling surplus is controlled in 14UM ± 1UM, to guarantee the abundance of the drafts of secondary cold-rolling；If drafts is insufficient, meeting
Hardness does not reach requirement.
3): when degreasing, guarantee that surface cleaning is clean, when bulk-breaking, by coil diameter control within 1.4 meters, volume size
Unanimously；Bell-type annealing Shi Jinlu in this way is put uniformly, and being heated will be uniform.
4): specific as follows when bell-type annealing:
(a) after in-furnace temperature reaches 400 degree, control rate of warming is 35 degree/hour, and temperature is added to 580 from 400 degree
Degree；In annealing, this is step key, and in order to guarantee hardness, the speed of heating determines the size of the thermal coefficient of steel, in steel
Carbon content and alloy amount are affected to heat transfer, and heating speed has to slowly, avoid internal-external temperature difference excessive, and cause tissue and
The unevenness of performance, this section are exactly the stage of strip tissue crystals, and are controlled and can be guaranteed in this stepwise heating speed
Strip tissue crystals are uniform, guarantee that hardness is high, through overtesting, it is found that this temperature range and heating speed are most suitable.
(b) when temperature reaches 580 degree, start to keep the temperature, soaking time is 15 hours；15 hours soaking times are volume temperature
Temperature control at 580 degree, thermally equivalent state would be to the heated of volume in this way, it is right to guarantee that crystal grain is uniform in strip
The determination of hardness plays this important function, moreover it is possible to guarantee the flexibility of finished product.
(c) Temperature fall after keeping the temperature, in Temperature fall to after 530 degree, mentioning heating mantles, the air-cooled and hot blow of progress,
At this moment the oil and gas and water in inner cover is driven away using protective gas, after air-cooled to 280 degree, then carry out water cooling to can just go out after 80 degree
Furnace；
(d) when falling to a certain temperature wait roll up temperature, milling train secondary cold-rolling is sent immediately, and the pumping of cold-rolling equipment is regulated in rolling
The position of roller guarantees that version type is smooth.When reaching 50 degree wait roll up temperature, milling train secondary cold-rolling is sent immediately.When second of cold rolling, control
Rolling pass processed is 2 times, and with the rolling of uniform speed, mill speed is 750-800 meters per minute.Such product, hardness reach
It marks and hardness is uniform, allowance control is good, and while guaranteeing hardness, because crystallization is uniformly, the flexibility of material can also be protected
Card.
Process flow in the bell type annealing furnace are as follows: coil of strip shove charge → placement inner cover → locking inner cover → cold conditions sealing inspection
It looks into, vacuumize → heating mantles placement, igniting → nitrogen charging hydrogen shield → heat preservation → Thermal Sealing inspection → air cooling → water cooling
→ finally vacuumizing → locks release → inner cover and removes, comes out of the stove
Annealing medium: natural gas, Annealing Protection gas: 75% hydrogen, 25% nitrogen.
Finished product test
One: 0.220mm thickness tinplate SPCC material of finished product, extension test speed: 100.000mm/min, stress strain curve figure
See attached drawing 1, as a result as follows:
Table one
Two: 0.140mm thickness tinplate SPCC material of finished product, extension test speed: 100.000mm/min, stress strain curve figure
See attached drawing 2, as a result as follows:
Table two
It can be seen from upper two table according to the present invention technique preparation two finished products, thickness 0.13-0.5mm feelings
Under condition, tensile strength is above 530MPa, that is, illustrates that its hardness number reaches DR7-DR8, in addition, it can be seen that theirs is disconnected
It splits elongation more than 5%, prolongs higher than the 2-3% of the tinplate product of condition of equivalent thickness under the secondary cold-rolling technique of conventional
The latitude of emulsion.
In the past, client can only improve the thickness of tinplate, but high-performance Ma Kou of the invention to reach hardness requirement
Iron, under the requirement for meeting high rigidity, minimum thickness can achieve 0.14-0.18mm, can only reach the horse of the hardness before
The 2/3 of mouth iron thickness is the specialities specifically for market food service industry of inventor's research and development, just because of it has both height firmly
Degree, thin thickness allow to substitute original widely used light-weighted aluminum products, after plating, anti-corrosive properties, tension
Property can also match in excellence or beauty with aluminum products.Moreover, not only cost is lower than original aluminum products for finished product of the invention, intensity also compares aluminum
Product are good, and improve on the slave integrated artistic for passing through inventor, especially improve the temperature control process such as annealing, reach
While rationally control secondary cold-rolling technique improves intensity, material internal crystallization is also made uniformly to ensure that good extension
Property, become the ideal packaging material for food of the country such as Middle East.
Especially, for food cans packaging when, pervious three-piece can produce (in the past, because the hardness of material with
Extensibility problem, these three parts of tank bottom, can body, cover can only all use different raw materials to prepare respectively) become two-piece can life
(now, using high-performance tinplate produced by the present invention, can achieve tank bottom and can body can use same material and be made into for production
One, i.e., high-performance tinplate finished product of the invention, because it is with high rigidity and extensibility, therefore now only needs cover list
Solely stock and preparation), and tank bottom and can body become an entirety, leakproofness and intensity are better than three-piece can, additionally improve
The production efficiency of rear end tank client reduces client cost, therefore the present invention has great economic value.
High-performance tinplate production technology of the invention, technique are unique, by the improvement to entire technique, the horse produced
Mouth iron intensity is good, and hardness is uniform, and version type is smooth, can achieve in the case where plate is very thin, the effect that hardness is very big, extensibility
Superior, component is light, is ideal packaging material for food and the favorite packaging material for food of middle east, and product
Various performances can reach client and preferably require.The plate that the present invention obtains is only 0.13MM-0.5MM in finished product thickness
When, hardness can reach DR7-DR8, be pervious technique have no idea realize, be conducive to user reduce product thickness, reduce at
This, in tinplate industry, has huge economic value, is worthy to be popularized.
The above description is merely a specific embodiment, but scope of protection of the present invention is not limited thereto, any
The change or replacement expected without creative work, should be covered by the protection scope of the present invention.Therefore, of the invention
Protection scope should be determined by the scope of protection defined in the claims.
Claims (5)
1. high-performance tinplate production technology, which is characterized in that prepared using secondary cold-rolling ferrostan technique, wherein
1): when sorting, selecting SPHC low carbon steel plate, the hardness of hot rolling is in the range of T2.5, and carbon content is between 3-5；
2): after pickling, when first time cold rolling, the deflection of first time is controlled, according to the requirement of deflection, second
Cold rolling surplus control within 14UM ± 1UM, to guarantee the abundance of the drafts of secondary cold-rolling；
3): when degreasing, guaranteeing that surface cleaning is clean, when bulk-breaking, by coil diameter control within 1.4 meters, volume size is consistent；
4): specific as follows when bell-type annealing:
(a) after in-furnace temperature reaches 400 degree, control rate of warming is 30-40 degree/hour, and temperature is added to 580 from 400 degree
Degree；
(b) when temperature reaches 580 degree, start to keep the temperature, soaking time is 14-16 hours；
(c) Temperature fall after keeping the temperature, in Temperature fall to after 530 degree, mentioning heating mantles, the air-cooled and hot blow of progress, at this moment
The oil and gas and water in inner cover is driven away using protective gas, after air-cooled to 280 degree, then carries out water cooling to can just come out of the stove after 80 degree；
(d) when falling to a certain temperature wait roll up temperature, milling train secondary cold-rolling is sent immediately, the roller of smoking of cold-rolling equipment is regulated in rolling
Position guarantees that version type is smooth.
2. high-performance tinplate production technology according to claim 1, which is characterized in that when sorting, select steel plate thickness
For 2.75mm.
3. high-performance tinplate production technology according to claim 1, which is characterized in that when second of cold rolling, control
Rolling pass processed is 2 times, and mill speed is 750-800 meters per minute.
4. high-performance tinplate production technology according to claim 1, which is characterized in that Annealing Protection in bell type annealing furnace
Gas is 75% hydrogen, 25% nitrogen.
5. high-performance tinplate production technology according to claim 1, which is characterized in that temperature drop to be rolled up is to 50 degree or less
When, send milling train secondary cold-rolling.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811636326.8A CN109628716A (en) | 2018-12-29 | 2018-12-29 | High-performance tinplate production technology |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811636326.8A CN109628716A (en) | 2018-12-29 | 2018-12-29 | High-performance tinplate production technology |
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| Publication Number | Publication Date |
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| CN109628716A true CN109628716A (en) | 2019-04-16 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811636326.8A Pending CN109628716A (en) | 2018-12-29 | 2018-12-29 | High-performance tinplate production technology |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112280944A (en) * | 2020-10-16 | 2021-01-29 | 粤海中粤(中山)马口铁工业有限公司 | Annealing method of tinplate substrate |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5669388A (en) * | 1979-11-08 | 1981-06-10 | Toyo Kohan Co Ltd | Preparation of raw tinplate excellent in wettability of sn plated layer and corrosion resistance of product |
| CN101649381A (en) * | 2009-09-10 | 2010-02-17 | 武汉钢铁(集团)公司 | Method for producing secondary cold-rolling tinning original plate |
| CN102794301A (en) * | 2012-08-03 | 2012-11-28 | 莱芜市泰山冷轧板有限公司 | Manufacture method of cold-rolled electrolytic tin substrate |
| CN105798061A (en) * | 2016-03-23 | 2016-07-27 | 天津炬坤金属科技有限公司 | Cold rolling method of ultrathin precise medium-width tinplate substrate of 0.05-0.1 mm with mirror surface light |
| CN107177788A (en) * | 2017-06-01 | 2017-09-19 | 首钢总公司 | A kind of secondary cold-rolling tin plate and its production method |
-
2018
- 2018-12-29 CN CN201811636326.8A patent/CN109628716A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5669388A (en) * | 1979-11-08 | 1981-06-10 | Toyo Kohan Co Ltd | Preparation of raw tinplate excellent in wettability of sn plated layer and corrosion resistance of product |
| CN101649381A (en) * | 2009-09-10 | 2010-02-17 | 武汉钢铁(集团)公司 | Method for producing secondary cold-rolling tinning original plate |
| CN102794301A (en) * | 2012-08-03 | 2012-11-28 | 莱芜市泰山冷轧板有限公司 | Manufacture method of cold-rolled electrolytic tin substrate |
| CN105798061A (en) * | 2016-03-23 | 2016-07-27 | 天津炬坤金属科技有限公司 | Cold rolling method of ultrathin precise medium-width tinplate substrate of 0.05-0.1 mm with mirror surface light |
| CN107177788A (en) * | 2017-06-01 | 2017-09-19 | 首钢总公司 | A kind of secondary cold-rolling tin plate and its production method |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112280944A (en) * | 2020-10-16 | 2021-01-29 | 粤海中粤(中山)马口铁工业有限公司 | Annealing method of tinplate substrate |
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