CN106670416B - One kind being suitable for carbon, silicon, the Uncrossed grade transition method of manganese element content - Google Patents
One kind being suitable for carbon, silicon, the Uncrossed grade transition method of manganese element content Download PDFInfo
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- CN106670416B CN106670416B CN201710017855.9A CN201710017855A CN106670416B CN 106670416 B CN106670416 B CN 106670416B CN 201710017855 A CN201710017855 A CN 201710017855A CN 106670416 B CN106670416 B CN 106670416B
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- steel
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/16—Controlling or regulating processes or operations
- B22D11/18—Controlling or regulating processes or operations for pouring
- B22D11/181—Controlling or regulating processes or operations for pouring responsive to molten metal level or slag level
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/16—Controlling or regulating processes or operations
- B22D11/20—Controlling or regulating processes or operations for removing cast stock
Abstract
The invention discloses one kind being suitable for the Uncrossed grade transition methods of chemical element contents such as carbon, silicon, manganese, belongs to technical field of ferrous metallurgy.This method is cast different steel grades using same continuous casting production, also, multiple chemical elements such as these steel grade carbon, silicon, manganese do not intersect, and successfully key is the stability contorting of the low liquid level of tundish and the accurate assurance of retention time.The present invention need not increase additional equipment, it is easy to operation, the useless base amount generated is few, by taking the continuous casting production of the band Ba Yan of molten steel net weight 45t as an example, steel scrap amount need not consume new continuous casting production substantially in 35t or so, it need not reorganize and pour time, cutting head cutting tail is not needed, production cost is greatly reduced, the smelting particularly suitable for the small lot high-quality steel with specific use produces.
Description
Technical field
The invention belongs to technical field of ferrous metallurgy, more particularly to a kind of carbon, silicon, manganese element content of being suitable for is not intersected
Grade transition method.
Background technology
With the development of national economy, demand of the country to the steel grade with specific use is more and more, such as extraordinary weldering
Silk steel, Bearing with high properties steel, pinion steel etc., still, the demand of these steel grades is frequently not very big, also, different clients are wanted
The chemical composition asked may also can be not quite similar, this just brings prodigious difficulty to the smelting of continuous casting.If one is poured secondary
Two or three stove steel is arranged, and pours time the first stove often due to the reason of the aspects such as molding casting and temperature are higher, the quality of steel
Generally will not be very high, meanwhile, no matter how much one poured time stove number, a continuous casting production will be consumed, continuous casting production
Cost is generally tens of thousands of yuan, and such casting sequence is few, therefore the increase that the costs of steel will be drastically is found a kind of suitable
It is extremely urgent for the Uncrossed grade transition method of carbon, silicon, manganese element content.
For the steel grade that carbon, silicon, manganese chemical element content intersect, as long as controlling the constituent content of transition heat at two
The transposition section of steel grade just can meet the requirement of two steel grades simultaneously, and many steel mills are all using the method now, but right
In carbon, silicon, the Uncrossed steel grade of manganese element content, since chemical composition section does not intersect, different steel grades are suitble to the temperature of casting
Degree also differs larger, meanwhile, the steel scrap of generation will also lack as far as possible, this just pours to company and brings prodigious difficulty, still, if
If succeeding in developing, the reduction for production cost, the enhancing of the market competitiveness, it will generate very important influence.
Invention content
The main problem that the application solves is to provide suitable for carbon, silicon, the Uncrossed grade transition of manganese element content
Method, with solve cannot achieve reduce carbon, silicon, manganese element content Uncrossed different steel grade continuous casting cost the technical issues of.
In order to solve the above-mentioned technical problem, it is Uncrossed different suitable for carbon, silicon, manganese element content that the invention discloses one kind
Steel grade even pours method, including step is implemented as follows：
1) it even pours and subcontracts：Direct casting M stove steel grade A, N stove steel grade B, M stove steel grades A normally casts, and subcontracts, works as continuous casting
When pouring basket liquid level is reduced to height H1, it is denoted as moment T1, pouring basket liquid level continues to reduce, and is reduced to higher than limiting altitude 50mm
Left and right, is advisable higher than limiting altitude 40-60mm, later, starts the first stove steel grade B that casts, subcontracts, pouring basket liquid level is kept to be in
Between limiting altitude and limiting altitude+150mm, after being kept for a period of time, the rapid pouring basket liquid level that promoted is to height H2, when being denoted as
T2 is carved, continues to lift up pouring basket liquid level later until normal casting liquid level；
2) throwing：Before moment T2, pulling rate is operated by the requirement of steel grade A, after moment T2, pulling rate by steel grade B requirement
Operation；The continuous casting billet pulled out between moment T1 to T2 is all sentenced useless；Preceding 2 strands that pull-out is often flowed after moment T2 are cast at every
Base respectively takes a sample end to end, detects the chemical composition of strand, and the qualified strand of ingredient is determined as qualified base end to end, individually
Storage；After follow-up strand rolling, every carries out being mingled with analyte detection.
Further, during the step 1) is even poured and subcontracted, casting M stove steel grade A continuous casting platforms temperature is compared with other stove steel
5-30 DEG C high, preferably higher than normal 10-20 DEG C of cast temperature when kind A casting, when the first stove steel grade B casts, continuous casting platform temperature
5-30 DEG C high, preferably higher than normal 10-20 DEG C of cast temperature when casting compared with other stove steel grades B.
Further, during the step 1) is even poured and subcontracted, the height H1 requires to determine according to steel grade A to field trash.
When to be mingled with species more by steel grade A, when content is high and the requirements such as inclusion content are difficult to control, H1 numerical value is larger；When steel grade A is mingled with
Species are few, and H1 numerical value is smaller when being easy to control, preferably 300,350 or 400mm of H1 numerical value.
Further, during the step 1) is even poured and subcontracted, the limiting altitude is according to tundish structure and deformation extent
It determines.Limiting altitude is also referred to as critical altitude, and the acquisition modes of critical altitude are obtained according to each tundish model, and the present invention is herein
It is not set forth in detail.It, can be using 150mm as limiting altitude value when obtaining difficult.
Further, during the step 1) is even poured and subcontracted, it is one heat steel that the time of the holding, which no less than draws steel amount,
Kind of B opens when pouring the time used in 2 times of molten steel amount in tundish.The retention time is advisable for 10-30min.
Further, during the step 1) is even poured and subcontracted, requirements of the height H2 according to steel grade B to field trash is true
It is fixed.When to be mingled with species more by steel grade B, when content is high and the requirements such as inclusion content are difficult to control, H2 numerical value is larger；As steel grade B
H2 numerical value is smaller when it is few to be mingled with species, and being easy to control, preferably 300,350 or 400mm of H2 numerical value.
Compared with prior art, of the present invention a kind of suitable for carbon, silicon, the Uncrossed different steel grade of manganese element content
Method is poured by company, has reached following effect：
(1) easy to operation, additional equipment need not be increased；
(2) continuous casting billet to sentence useless amount less, by taking the continuous casting production of the band Ba Yan of molten steel net weight 45t as an example, steel scrap amount base
This control is in 35t or so；
(3) new continuous casting production need not be consumed, need not reorganize and pour time, not need cutting head cutting tail, drop significantly
Low production cost.
Specific implementation mode
Some vocabulary has such as been used to censure particular step in specification and claim.Those skilled in the art answer
It is understood that those skilled in the art may call same step with different nouns.This specification and claims not with
The difference of step title is used as the mode for distinguishing step, but is used as the criterion of differentiation with the purpose of implementation steps.Such as exist
The "comprising" of specification and claim mentioned in is an open language in the whole text, therefore should be construed to " include but do not limit
In "." substantially " refer in receivable error range, those skilled in the art can be described within a certain error range solution
Technical problem basically reaches the technique effect.Specification subsequent descriptions are to implement the better embodiment of the application, so described
Description is being not limited to scope of the present application for the purpose of the rule for illustrating the application.The protection domain of the application
When subject to appended claims institute defender.
Embodiment 1
The present embodiment 1 provides a kind of No. 45 steel of production and method is poured by the company of 60CrMnBA.Certain produces 13 stove steel, 1-
12 stoves are No. 45 steel, and last 1 stove is 60CrMnBA, and specific implementation step is：
1) it even pours and subcontracts：No. 45 steel of 1-11 stoves are normally cast, and when the 12nd steel of stove 45 is cast, steel casts platform than before
15 DEG C of heating is subcontracted after the completion of the casting of the 12nd steel of stove 45, pouring basket liquid level is gradually dropped to 300mm (H1), records the time 23:
45 (T1), liquid level continue to drop to 200mm or so (limit liquid level 150mm), start the 1st stove 60CrMnBA that casts, and when casting protects
16 DEG C when demonstrate,proving steel casting platform higher than normal casting 60CrMnBA, pouring basket liquid level rises, and ensures pouring basket liquid level in 200-270mm
Between, retention time 20min.Pouring basket liquid level is promoted to 300mm or so (H2) rapidly later, is recorded the time：00:07
(T2), pouring basket liquid level continues to improve later, it is known that reaches normal casting liquid level 800mm；
2) throwing：Since the pulling rate of No. 45 steel and 60CrMnBA is 0.75m/min, process pulling rate guarantor is even poured in this time
It holds constant；23:45-00:The continuous casting billet pulled out in 07 (T1-T2) period is all sentenced useless；0:Often stream is drawn after 07 (T2)
Preceding 2 strands gone out take a sample end to end in every strand, and the chemical composition of strand is detected according to table 3, and ingredient is whole
Positioned at 3 range of table, it is determined as qualification, individually stores, it is also all qualified that follow-up rolling is mingled with analyte detection.
It pours process with company and is operated according to normal flow.
Detection：
No. 45 steel：It is 1-12 stoves 45 that the chemical composition of detection 1-12 No. 45 steel of stove, testing result are required according to table 1
The chemical composition of steel is located at the range of table 1, No. 45 steel qualifications that company pours.
60CrMnBA：It is the 13rd stove that the chemical composition of the 60CrMnBA of the 13rd stove of detection, testing result are required according to table 2
The chemical composition of 60CrMnBA is located at the range of table 2, and the 60CrMnBA that company pours is qualified.
The requirement of 1 45 steel chemical composition of table, %
| Steel grade | C | Si | Mn | Cr≤ | P≤ | S≤ | Ni≤ | Cu≤ |
| 45 | 0.42-0.50 | 0.17-0.37 | 0.50-0.80 | 0.25 | 0.03 | 0.03 | 0.3 | 0.25 |
The requirement of 2 60CrMnBA chemical compositions of table, %
The 13rd stove 60CrMnBA of table 3 often flows the chemical composition ranges section of preceding 2 semifinished products, %
Embodiment 2
The present embodiment 2, which provides, a kind of producing S20C-Cr and method is poured by the company of 52CrMoV4.Certain produces 9 stove steel, and preceding 7
Stove is S20C-Cr, and last 2 stove is 52CrMoV4, and specific implementation step is：
1) it even pours and subcontracts：Preceding 6 stove S20C-Cr normally casts, and when the 7th stove S20C-Cr casts, steel casting platform rises than before
16 DEG C of temperature is subcontracted after the completion of the 7th stove S20C-Cr casting, pouring basket liquid level is gradually dropped to 400mm (H1), records the time 22:22
(T1), liquid level continues to drop to 200mm or so (limit liquid level 150mm), starts the 1st stove 52CrMoV4 that casts, and when casting ensures
17 DEG C when steel casts platform higher than normal casting 52CrMoV4, pouring basket liquid level rises, ensure pouring basket liquid level 190-260mm it
Between, retention time 15min.Pouring basket liquid level is promoted to 400mm or so (H2) rapidly later, is recorded the time：22:40
(T2), pouring basket liquid level continues to improve later, it is known that reaches normal casting liquid level 800mm；
2) throwing：22:The pulling rate 0.8m/min throwings of S20C-Cr before 40,22:According to the pulling rate of 52CrMoV4 after 40
0.75m/min throwings；22:22-22:The continuous casting billet pulled out in 40 (T1-T2) periods is all sentenced useless；22:40 (T2) it
Preceding 2 strands for often flowing pull-out afterwards take a sample in every strand, the chemical composition of strand are detected according to table 6 end to end,
Ingredient is entirely located in 3 range of table, is determined as qualification, individually stores, and it is also all qualified that follow-up rolling is mingled with analyte detection.
It pours process with company and is operated according to normal flow.
Detection：
S20C-Cr：It is 1-7 stoves that the chemical composition of detection 1-7 stoves S20C-Cr, testing result are required according to table 4
The chemical composition of S20C-Cr is located at the range of table 4, and the S20C-Cr that company pours is qualified.
52CrMoV4：It is 8-9 stoves that the chemical composition of the 52CrMoV4 of detection 8-9 stoves, testing result are required according to table 5
The chemical composition of 52CrMoV4 be located at the range of table 5, the 52CrMoV4 that company pours is qualified.
The requirement of table 4S20C-Cr chemical compositions, %
The requirement of 5 52CrMoV4 chemical compositions of table, %
The 8th stove 52CrMoV4 of table 6 often flows the chemical composition ranges section of preceding 2 semifinished products, %
Compared with prior art, of the present invention a kind of suitable for carbon, silicon, the Uncrossed different steel grade of manganese element content
Method is poured by company, has reached following effect：
(1) easy to operation, additional equipment need not be increased；
(2) continuous casting billet to sentence useless amount less, save resource, improve productivity；
(3) new continuous casting production need not be consumed, need not reorganize and pour time, not need cutting head cutting tail, drop significantly
Low production cost.
Several preferred embodiments of the application have shown and described in above description, but as previously described, it should be understood that the application
Be not limited to form disclosed herein, be not to be taken as excluding other embodiments, and can be used for various other combinations,
Modification and environment, and the above teachings or related fields of technology or knowledge can be passed through in application contemplated scope described herein
It is modified.And changes and modifications made by those skilled in the art do not depart from spirit and scope, then it all should be in this Shen
It please be in the protection domain of appended claims.
Claims (6)
1. one kind being suitable for carbon, silicon, the Uncrossed grade transition method of manganese element content, which is characterized in that including following real
Apply step：
1) it even pours and subcontracts：Direct casting M stove steel grade A, N stove steel grade B, M stove steel grades A normally casts, and subcontracts, among continuous casting
When packet liquid level is reduced to height H1, it is denoted as moment T1, pouring basket liquid level continues to reduce, and is reduced to higher than limiting altitude 40-60mm,
Later, start the first stove steel grade B that casts, subcontract, pouring basket liquid level is kept to be between limiting altitude and limiting altitude+150mm,
After being kept for a period of time, the rapid pouring basket liquid level that promoted is denoted as moment T2, it is straight to continue to lift up pouring basket liquid level later to height H2
To normal casting liquid level；
2) throwing：Before moment T2, pulling rate is operated by the requirement of steel grade A, and after moment T2, pulling rate is operated by the requirement of steel grade B；
The continuous casting billet pulled out between moment T1 to T2 is all sentenced useless；Preceding 2 strands that pull-out is often flowed after moment T2, in the head of every strand
Tail respectively takes a sample, detects the chemical composition of strand, and the qualified strand of ingredient is determined as qualified base end to end, individually stores；
After follow-up strand rolling, every carries out being mingled with analyte detection.
2. according to claim 1 be suitable for carbon, silicon, the Uncrossed grade transition method of manganese element content, feature
It is, during the step 1) is even poured and is subcontracted, casting M stove steel grade A continuous casting platforms temperature high 5- when casting compared with other stove steel grades A
30 DEG C, when the first stove steel grade B casts, continuous casting platform temperature is 5-30 DEG C high when casting compared with other stove steel grades B.
3. according to claim 1 be suitable for carbon, silicon, the Uncrossed grade transition method of manganese element content, feature
It is, during the step 1) is even poured and subcontracted, the height H1 requires to determine according to steel grade A to field trash.
4. according to claim 1 be suitable for carbon, silicon, the Uncrossed grade transition method of manganese element content, feature
It is, during the step 1) is even poured and subcontracted, the limiting altitude is determined according to tundish structure and deformation extent.
5. according to claim 1 be suitable for carbon, silicon, the Uncrossed grade transition method of manganese element content, feature
It is, during the step 1) is even poured and subcontracted, it is that the first stove steel grade B is opened among when pouring that the time of the holding, which no less than draws steel amount,
Time in packet used in 2 times of molten steel amount.
6. according to claim 1 be suitable for carbon, silicon, the Uncrossed grade transition method of manganese element content, feature
It is, during the step 1) is even poured and subcontracted, requirements of the height H2 according to steel grade B to field trash determines.
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| CN107999717A (en) * | 2017-12-11 | 2018-05-08 | 南京钢铁股份有限公司 | A kind of generous specification slab grade transition production technology |
| CN111331096B (en) * | 2020-03-19 | 2022-02-25 | 山西太钢不锈钢股份有限公司 | Method for eliminating bubbles of duplex stainless steel |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06210415A (en) * | 1993-01-12 | 1994-08-02 | Sumitomo Metal Ind Ltd | Method for preventing flow-out of slag in tundish |
| CN102266927A (en) * | 2011-08-01 | 2011-12-07 | 东北大学 | Control method for molten-steel casting sequence of continuous casting machine |
| CN103406513A (en) * | 2013-08-23 | 2013-11-27 | 山西太钢不锈钢股份有限公司 | Continuous casting method of dissimilar stainless steel |
| CN103706775A (en) * | 2013-12-13 | 2014-04-09 | 内蒙古包钢钢联股份有限公司 | Operation method for simultaneously casting secondary and special steel type long continuous castings through continuous casting machine for wide and thick plates |
| CN104561826A (en) * | 2014-11-26 | 2015-04-29 | 南京钢铁股份有限公司 | Low-alloy high-strength structural steel Q460C strip steel and production process thereof |
| CN105483310A (en) * | 2015-11-23 | 2016-04-13 | 东北大学 | Steelmaking batch grouping and production scheduling method for whole process production |
-
2017
- 2017-01-11 CN CN201710017855.9A patent/CN106670416B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06210415A (en) * | 1993-01-12 | 1994-08-02 | Sumitomo Metal Ind Ltd | Method for preventing flow-out of slag in tundish |
| CN102266927A (en) * | 2011-08-01 | 2011-12-07 | 东北大学 | Control method for molten-steel casting sequence of continuous casting machine |
| CN103406513A (en) * | 2013-08-23 | 2013-11-27 | 山西太钢不锈钢股份有限公司 | Continuous casting method of dissimilar stainless steel |
| CN103706775A (en) * | 2013-12-13 | 2014-04-09 | 内蒙古包钢钢联股份有限公司 | Operation method for simultaneously casting secondary and special steel type long continuous castings through continuous casting machine for wide and thick plates |
| CN104561826A (en) * | 2014-11-26 | 2015-04-29 | 南京钢铁股份有限公司 | Low-alloy high-strength structural steel Q460C strip steel and production process thereof |
| CN105483310A (en) * | 2015-11-23 | 2016-04-13 | 东北大学 | Steelmaking batch grouping and production scheduling method for whole process production |
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