CN113828748A - Automatic control system and method for preventing molten steel from being oxidized in whole continuous casting process - Google Patents
Automatic control system and method for preventing molten steel from being oxidized in whole continuous casting process Download PDFInfo
- Publication number
- CN113828748A CN113828748A CN202010578468.4A CN202010578468A CN113828748A CN 113828748 A CN113828748 A CN 113828748A CN 202010578468 A CN202010578468 A CN 202010578468A CN 113828748 A CN113828748 A CN 113828748A
- Authority
- CN
- China
- Prior art keywords
- tundish
- gas
- pipeline
- purging
- molten steel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- 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
-
- 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
- B22D11/10—Supplying or treating molten metal
- B22D11/11—Treating the molten metal
- B22D11/111—Treating the molten metal by using protecting powders
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
- B22D41/50—Pouring-nozzles
- B22D41/58—Pouring-nozzles with gas injecting means
-
- 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
- Y02P10/10—Reduction of greenhouse gas [GHG] emissions
- Y02P10/143—Reduction of greenhouse gas [GHG] emissions of methane [CH4]
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Continuous Casting (AREA)
Abstract
The invention discloses an automatic control system and a method for preventing molten steel from being oxidized in the whole continuous casting process, which are respectively connected to a connecting position between a ladle discharging port and a long nozzle and a tundish, and comprise a long nozzle gas seal pipeline connected to the connecting position, a tundish purging and gas seal pipeline connected to the tundish and a tundish purging gas pipeline connected to the tundish; a gas mixing chamber is communicated between the tundish purging and gas sealing pipeline and the tundish purging gas pipeline; the long water gap gas seal pipeline, the tundish purging and gas seal pipeline and the tundish purging gas pipeline are also connected to a control terminal. The invention improves the automation degree of field operation, reduces the oxygen atmosphere of the tundish, reduces the nitrogen increase of continuous casting molten steel, and meets the continuous casting production requirements of various high-grade steel grades.
Description
Technical Field
The invention relates to a slab continuous casting technology, in particular to an automatic control system and method for preventing molten steel from being oxidized in the whole continuous casting process.
Background
In the continuous casting production process, secondary oxidation of molten steel is the most critical factor that deteriorates the quality of a cast slab, and prevention of secondary oxidation of molten steel in the continuous casting process is the goal of all continuous casting workers. The main technology for preventing secondary oxidation of molten steel in continuous casting at present is as follows: covering agent is put on the steel liquid surfaces of the steel ladle and the tundish, and the casting powder is added on the crystallizer to isolate the contact of the molten steel and air, so that the secondary oxidation of the molten steel is avoided.
However, the air suction phenomenon in the continuous casting process still exists because the negative pressure air suction caused by the existence of the fluidity of the molten steel and the covering agent can not completely cover the molten steel surface. Therefore, a method for protective pouring by using argon is developed in the industry, although various argon seals are used for preventing secondary oxidation, the method needs to be operated by operators according to different working conditions, the effect is unstable, the labor intensity and the operation safety of the operators are greatly improved, meanwhile, the effect of only blowing in and replacing by using argon is still not ideal, and the plate blank of the first furnace of the tundish still degrades more.
In the whole continuous casting process, molten steel mainly has three processes from a steel ladle to a tundish, wherein the three processes are easy to oxidize:
1) after baking, preparing a poured air tundish, wherein a large amount of air exists in the tundish, and molten steel initially entering the tundish is quickly oxidized;
2) when molten steel of a steel ladle enters a tundish, along with the downward flow of the molten steel at a high speed, a connecting part between a ladle down nozzle and a long nozzle becomes a negative pressure point for sucking air, so that the molten steel is oxidized;
3) in the pouring process, air exists between the liquid level of the tundish steel and the tundish cover, and molten steel is oxidized.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide an automatic control system and method for preventing molten steel from being oxidized in the whole continuous casting process, so that the automation degree of field operation is improved, the oxygen atmosphere of a tundish is reduced, the nitrogen increase of continuous casting molten steel is reduced, and the continuous casting production requirements of various high-grade steel grades are met.
In order to achieve the purpose, the invention adopts the following technical scheme:
on one hand, the automatic control system for preventing molten steel from being oxidized in the whole continuous casting process is respectively connected to a connecting position between a ladle discharging port and a long nozzle and a tundish and comprises a long nozzle gas seal pipeline connected to the connecting position, a tundish purging and gas seal pipeline connected to the tundish and a tundish purging gas pipeline connected to the tundish;
a gas mixing chamber is communicated between the tundish purging and gas sealing pipeline and the tundish purging gas pipeline;
the automatic control system also comprises a control terminal which is used for controlling the long water gap gas seal pipeline, the tundish purging and gas seal pipeline and the tundish purging gas pipeline.
Preferably, the long nozzle gas seal pipeline, the tundish purging pipeline and the gas seal pipeline all adopt argon gas; the tundish purging gas pipeline adopts natural gas.
Preferably, the long nozzle gas seal pipeline comprises a first gas conveying pipe, and a first regulating valve, a first cut-off valve and a first flowmeter are sequentially arranged on the first gas conveying pipe along the gas conveying direction; and/or
Middle package sweeps and gas seal pipeline includes the gaseous conveyer pipe of second, be equipped with second governing valve, second trip valve and second flowmeter in proper order along gas conveying direction on the gaseous conveyer pipe of second, the gaseous conveyer pipe of second with gas mixing chamber intercommunication, gas mixing chamber pass through the gas pipeline with middle package intercommunication.
Preferably, the tundish purging gas pipeline comprises a third gas conveying pipe, a third regulating valve, a third stop valve and a third flow meter are sequentially arranged on the third gas conveying pipe along the gas conveying direction, the third gas conveying pipe is communicated with the gas mixing chamber, and the gas mixing chamber is communicated with the tundish through a gas pipeline.
On the other hand, the automatic control method for preventing molten steel from being oxidized in the whole continuous casting process controls the tundish purging and gas seal pipeline and the tundish purging gas pipeline through the control terminal in the system so as to realize automatic control of tundish purging and gas seal;
and controlling the long nozzle gas seal pipeline to realize the automatic control of the ladle long nozzle gas seal.
Preferably, the automatic control of the tundish purging and the gas seal comprises:
blowing argon into the tundish by using the tundish blowing and air sealing pipeline after preheating of the tundish is finished and before pouring is prepared, and replacing air in the tundish;
when argon is blown in, the tundish blowing gas pipeline blows natural gas into the tundish, and the air which is not fully replaced is consumed by combustion in the tundish, so that the air in the tundish is fully replaced;
and when the pouring of the tundish is started, after a covering agent is thrown on the surface of the molten steel in the tundish, automatically switching the amount of argon for blowing to the amount of argon for gas sealing, and closing the purging gas pipeline of the tundish until the pouring of the tundish is finished.
Preferably, the amount of argon for blowing is 3000-8000 l/min, and the pressure is 0.6-0.8 MPa; and/or the amount of argon for air sealing is 1000-3000 l/min, and the pressure is 0.6-0.8 MPa.
Preferably, the amount of the natural gas is 3 to 5% of the amount of the argon gas for blowing.
Preferably, the automatic control of the tundish purging and the gas seal further comprises the following steps:
1) setting the amount of argon for blowing and the amount of argon for gas sealing on the control terminal, setting the amount of natural gas according to 3-5% of the amount of argon for blowing, and selecting an automatic mode;
2) when the preheating of the tundish is finished, after the control terminal gives a preheating finishing signal, a second cut-off valve in the tundish purging and gas seal pipeline is automatically opened, and a second regulating valve in the tundish purging and gas seal pipeline regulates the flow to a set value of the amount of argon for blowing according to a second flowmeter in the tundish purging and gas seal pipeline;
3) meanwhile, a third cut-off valve in the tundish purging gas pipeline is automatically opened, a third regulating valve in the tundish purging gas pipeline regulates the flow to a set value of the natural gas amount according to a third flow meter in the tundish purging gas pipeline, and the tundish purging is started;
4) when the tundish starts to pour, the molten steel in the tundish is weighed to be more than or equal to 15-20 tons, and after a covering agent is added to the surface of the molten steel in the tundish, the third cut-off valve and the third regulating valve are automatically closed;
5) meanwhile, the second regulating valve regulates the flow to a set value of the argon amount for gas seal according to the second flowmeter, the tundish blowing is finished, and the gas seal is started;
6) and when the pouring of the tundish is finished, weighing the molten steel in the tundish is less than or equal to 10 tons, automatically closing the second stop valve and the second regulating valve, and finishing the gas seal.
Preferably, in the step 4), the covering agent is added before the first furnace of the tundish is started to be poured and the argon purging is closed;
the covering agent is added into the first furnace of the tundish according to the weight of 1-1.5% of the rated molten steel of the tundish, and then added according to the weight of 0.1-0.2% of the molten steel of each furnace of the tundish;
and when molten steel is exposed on the surface of the molten steel in the tundish, supplementing the covering agent at the exposed position.
Preferably, the automatic control of the ladle long nozzle gas seal comprises:
before pouring of the tundish is started, argon gas flow for gas sealing is set on the control terminal, an automatic mode is selected, and when the rotary arm carrying the ladle reaches a pouring position, the long nozzle gas sealing pipeline blows the argon gas flow for gas sealing into the connecting position of the long nozzle and the upper and lower nozzles of the ladle for gas sealing.
Preferably, the automatic control of the gas seal of the ladle long nozzle further comprises the following steps:
s1, before pouring of the tundish is started, setting argon flow for air sealing on the control terminal, and selecting an automatic mode;
s2, when the rotating arm carrying the ladle reaches the pouring position, a first cut-off valve in the long nozzle gas seal pipeline is automatically opened, a first regulating valve in the long nozzle gas seal pipeline regulates the flow to a set value of argon flow for gas seal according to a first flow meter in the long nozzle gas seal pipeline, and the ladle long nozzle gas seal starts to be carried out;
s3, when the pouring of the tundish is finished and the rotary arm leaves the pouring position, the first cut-off valve is automatically closed, the rotary arm carries the next ladle to the pouring position, and the first cut-off valve is automatically opened;
and S4, circularly performing the steps S1 to S3 until a pouring end signal is input to the control terminal, and ending the air sealing of the ladle long nozzle.
The automatic control system and the method for preventing molten steel from being oxidized in the whole continuous casting process can be widely applied to casting machine control systems of various continuous casting machines, have the advantages of reducing the oxygen content in a tundish, reducing the operation strength, avoiding the close-distance operation between workers and molten steel in a steel ladle, improving the operation safety and the automation degree, and improving the slab quality, have important significance, and are particularly suitable for the pouring of various high-grade steel grades in continuous casting.
Drawings
FIG. 1 is a schematic diagram of a configuration framework of the system of the present invention;
FIG. 2 is a schematic flow diagram of automatic tundish purge and gas seal control in the process of the present invention;
FIG. 3 is a schematic flow chart of the automatic control of the ladle long nozzle gas seal in the method of the invention.
Detailed Description
The technical scheme of the invention is further explained by combining the drawings and the embodiment.
Referring to fig. 1, the automatic control system for preventing molten steel from being oxidized in the whole continuous casting process, provided by the present invention, is connected to the connection position between the down nozzle and the long nozzle 2 of the ladle 1 and the tundish 3, respectively, and comprises a long nozzle gas seal pipeline 100 connected to the connection position between the down nozzle and the long nozzle 2 of the ladle 1, a tundish purge and gas seal pipeline 200 connected to the tundish 3, and a tundish purge gas pipeline 300 connected to the tundish 3.
The automatic control system also comprises a control terminal which is used for remotely and automatically controlling the long-nozzle gas seal pipeline 100, the tundish purging and gas seal pipeline 200 and the tundish purging gas pipeline 300. Argon is adopted for the long nozzle gas seal pipeline 100 and the tundish purging and gas seal pipeline 200.
The tundish purge gas line 300 is natural gas.
The long nozzle gas seal pipeline 100 comprises a first gas delivery pipe, and a first regulating valve 101, a first cut-off valve 102 and a first flowmeter 103 are sequentially arranged on the first gas delivery pipe along the gas delivery direction.
The tundish purging and gas seal pipeline 200 comprises a second gas conveying pipe, a second regulating valve 201, a second stop valve 202 and a second flowmeter 203 are sequentially arranged on the second gas conveying pipe along the gas conveying direction, the second gas conveying pipe is communicated with a gas mixing chamber 4, and the gas mixing chamber 4 is communicated with a tundish 3 through a gas pipeline.
The tundish purge gas pipeline 300 comprises a third gas conveying pipe, a third regulating valve 301, a third stop valve 302 and a third flow meter 303 are sequentially arranged on the third gas conveying pipe along the gas conveying direction, the third gas conveying pipe is communicated with a gas mixing chamber 4, and the gas mixing chamber 4 is communicated with the tundish 3 through a gas pipeline.
The invention also provides an automatic control method for preventing molten steel from being oxidized in the whole continuous casting process, and the tundish purging and gas seal pipeline 200 and the tundish purging gas pipeline 300 are controlled by the control terminal so as to realize the flow of automatic tundish purging and gas seal control.
And the long nozzle gas seal pipeline 100 is controlled through the control terminal, so that the automatic control process of the ladle long nozzle gas seal is realized.
The flow of tundish purging and air seal automatic control comprises the following steps:
when the continuous casting starts to pour, a large amount of air exists in the preheated air tundish, and oxidation reaction is generated after molten steel enters, so that the quality of the molten steel is seriously deteriorated, and the quality of a continuous casting initial plate blank is degraded. After preheating of the tundish 3 is finished and before pouring is prepared, a certain amount of argon is blown into the tundish 3 through the tundish blowing and air sealing pipeline 200, and air in the tundish 3 is replaced;
while argon is blown in, the tundish blowing gas pipeline 300 blows natural gas into the tundish, so that air which is not fully replaced is combusted and consumed in the tundish 3 and oxygen brought in when argon is blown in, and the air in the tundish 3 is fully replaced;
when pouring of the tundish 3 is started, a certain amount of molten steel is contained in the tundish 3, and after the covering agent is thrown into the surface of the molten steel, the amount of argon for blowing is automatically switched to the amount of argon for gas sealing, and natural gas blowing of the tundish purging gas pipeline 300 is closed until pouring of the tundish 3 is finished.
The amount of argon gas to be blown in is 3000 to 8000l/min, and the pressure is 0.6 to 0.8 MPa.
The amount of argon gas for air sealing is 1000-3000 l/min, and the pressure is 0.6-0.8 MPa.
The natural gas amount is 3-5% of the argon amount for blowing.
Referring to fig. 2, the automatic control of the tundish purge and the gas seal further includes the following steps:
1) setting an argon amount for blowing and an argon amount for gas sealing (different according to steel type registration requirements and tundish capacity) on a control terminal, setting a natural gas amount according to 3-5% of the argon amount for blowing, and selecting an automatic mode;
2) when the preheating of the tundish 3 is finished, after an operator gives a preheating finishing signal at a control terminal, a second cut-off valve 202 in the tundish purging and gas seal pipeline 200 is automatically opened, and a second regulating valve 201 in the tundish purging and gas seal pipeline 200 regulates the flow to a set value of the amount of argon for blowing according to a second flow meter 203 in the tundish purging and gas seal pipeline 200;
3) meanwhile, a third cut-off valve 302 in the tundish purging gas pipeline 300 is automatically opened, a third regulating valve 301 in the tundish purging gas pipeline 300 regulates the flow to a set value of the natural gas amount according to a third flow meter 303 in the tundish purging gas pipeline 300, and the tundish purging is started;
4) when the tundish 3 starts to pour, the molten steel in the tundish 3 is weighed to be more than or equal to X tons (generally 15-20 tons can be set according to the molten steel weighing of the tundish 3 when the covering agent is put into the tundish 3), and after the covering agent is added to the surface of the molten steel in the tundish 3, the third stop valve 302 and the third regulating valve 301 are automatically closed;
5) meanwhile, the flow of the second regulating valve 201 is regulated to a set value of the argon gas for gas seal according to the second flowmeter 203, the purging of the tundish is finished, and the gas seal of the tundish is started;
6) when pouring of the tundish 3 is finished, the weight of molten steel in the tundish 3 is less than or equal to 10 tons, the second stop valve 202 and the second regulating valve 201 are automatically closed, and the air seal of the tundish is finished.
In step 4), the requirements for the addition process of the covering agent are as follows:
pouring in a first furnace of the tundish 3, and adding a covering agent before argon purging is closed;
the adding amount of the covering agent in the first furnace of the tundish 3 is 1-1.5% of the rated weight of the molten steel of the tundish 3, and then 0.1-0.2% of the weight of the molten steel of each furnace of the tundish 3;
when molten steel is exposed on the surface of the molten steel in the tundish 3, covering agent is added at the exposed position.
The automatic control process of the ladle long nozzle air seal comprises the following steps:
and controlling automatic argon sealing by using the position information of the ladle 1. Before pouring of the tundish 3 is started, an operator sets the flow rate of argon gas for gas sealing on a control terminal, selects an automatic mode, and when a swing arm (see a or B in fig. 1 again) carrying the ladle 3 reaches a pouring position, the long nozzle gas sealing pipeline 100 blows the flow rate of argon gas for gas sealing into a connecting position of the long nozzle 2 and a lower nozzle on the ladle 1 for gas sealing.
The flow of argon gas for air sealing is 10-15 m3The pressure is between 0.6 and 0.8 MPa.
Please refer to fig. 3, the automatic control of the ladle long nozzle gas seal further includes the following steps:
s1, before pouring of the tundish 3 is started, an operator sets the argon flow for air sealing on the control terminal and selects an automatic mode;
s2, when the rotating arm carrying the ladle 1 reaches the pouring position, the first cut-off valve 102 in the long nozzle gas seal pipeline 100 is automatically opened, the first regulating valve 101 in the long nozzle gas seal pipeline 100 regulates the flow to the set value of argon flow for gas seal according to the first flow meter 103 in the long nozzle gas seal pipeline 100, and the ladle long nozzle gas seal starts to be carried out;
s3, when the pouring of the middle ladle 3 is finished and the rotary arm leaves the pouring position, the first cut-off valve 102 is automatically closed, the rotary arm carries the next ladle 1 to the pouring position, and the first cut-off valve 102 is automatically opened;
and S4, circularly performing the steps S1 to S3 until the operator inputs a pouring end signal on the control terminal and the air sealing of the ladle long nozzle is finished.
Example 1
The invention discloses a 1# continuous casting machine in a steel plant of a certain iron and steel enterprise, which adopts the method of the invention: before pouring the tundish 3, an operator sets the argon gas amount for purging to 4000L/min and the argon gas amount for gas seal to 1000L/min, sets the natural gas amount to 150L/min, sets the tonnage of the tundish 3 to 15 tons at the purging end and the argon seal starting point, and sets the argon gas flow for gas seal of the long nozzle to 15m3And h, selecting the automatic mode for the blowing of the tundish, the air seal control and the air seal control of the ladle long nozzle.
When the preheating of the tundish 3 is finished, an operator gives a preheating finishing signal at a control terminal (L1), the second stop valve 202 is automatically opened, and the second regulating valve 201 regulates the flow to the set value 4000L/min according to the second flowmeter 203; and simultaneously, the third stop valve 302 is automatically opened, the third regulating valve 301 regulates the flow to the set value of 150L/min according to the third flow meter 303, and the argon purging of the tundish is started.
When the pivoting arm A reaches the pouring position, the first shut-off valve 102 opens automatically and the first regulating valve 101 opens according to the first flowThe meter 103 regulates the flow to a set value of 15m3And h, argon sealing of the long nozzle is started.
When the molten steel enters the tundish 3 from the ladle 1 at the beginning of pouring and the weight of the molten steel in the tundish 3 is more than or equal to 15 tons, 500kg of covering agent is uniformly added on the surface of the molten steel in the tundish 3, and the third regulating valve 301 and the third stop valve 302 are closed; meanwhile, the flow is regulated to the argon sealing argon flow rate of 1000L/min by the second regulating valve 201, the tundish purging is terminated, and the argon sealing is started.
When the rotary arm A leaves the pouring position, the first cut-off valve 102 is automatically closed, and after an operator sends a pouring end signal at a control terminal (L1), the first regulating valve 101 is automatically closed, and the argon sealing of the ladle long nozzle is automatically ended.
After casting of each ladle 1, 50kg of covering agent is uniformly added on the surface of the molten steel in the tundish 3.
Before pouring is finished, when the weight of the molten steel in the tundish 3 is less than or equal to 10 tons, the second stop valve 202 and the second regulating valve 201 are automatically closed, argon sealing is finished, and the purging of the tundish and the automatic argon sealing control process are finished.
Before and after the method is adopted, the oxygen partial pressure in the tundish 3 is detected and compared with the following results: the oxygen partial pressure (Po2) in the tundish 3 before use was 4%, and the oxygen partial pressure (Po2) in the tundish after use was 1%; the steel water sample [ N ] in the tundish 3 is tested, 3PPM is added to the [ N ] before use compared with the previous procedure, and 1PPM is added to the [ N ] after use compared with the previous procedure.
Example 2
The invention discloses a 3# continuous casting machine in a steel plant of a certain iron and steel enterprise, which adopts the method of the invention: before pouring the tundish 3, an operator sets the argon amount for purging to be 5000L/min and the argon amount for gas seal to be 2000L/min, sets the natural gas amount to be 200L/min, sets the tonnage of the tundish 3 to be 20 tons at the purging end and the argon seal starting point, and sets the argon flow for gas seal of the long nozzle to be 15m3And h, selecting the automatic mode for the blowing of the tundish, the air seal control and the air seal control of the ladle long nozzle.
When the preheating of the tundish 3 is finished, an operator gives a preheating finishing signal at a control terminal (L1), the second stop valve 202 is automatically opened, and the second regulating valve 201 regulates the flow to a set value of 5000L/min according to the second flowmeter 203; and simultaneously, the third stop valve 302 is automatically opened, the third regulating valve 301 regulates the flow to the set value of 200L/min according to the third flow meter 303, and the argon purging of the tundish is started.
When the rotary arm A reaches the pouring position, the first cut-off valve 102 is automatically opened, and the first regulating valve 101 regulates the flow rate to a set value of 15m according to the first flowmeter 1033And h, argon sealing of the long nozzle is started.
When the molten steel enters the tundish 3 from the ladle 1 at the beginning of pouring and the weight of the molten steel in the tundish 3 is more than or equal to 15 tons, 750kg of covering agent is uniformly added on the surface of the molten steel in the tundish 3, and the third regulating valve 301 and the third stop valve 302 are closed; meanwhile, the flow is regulated to 2000L/min of argon sealing argon flow by the second regulating valve 201, the tundish purging is stopped, and the argon sealing is started.
When the rotary arm A leaves the pouring position, the first cut-off valve 102 is automatically closed, and after an operator sends a pouring end signal at a control terminal (L1), the first regulating valve 101 is automatically closed, and the argon sealing of the ladle long nozzle is automatically ended.
After casting of each ladle 1, 80kg of covering agent is uniformly added on the surface of the molten steel of the tundish 3.
Before pouring is finished, when the weight of the molten steel in the tundish 3 is less than or equal to 10 tons, the second stop valve 202 and the second regulating valve 201 are automatically closed, argon sealing is finished, and the purging of the tundish and the automatic argon sealing control process are finished.
Before and after the method is adopted, the oxygen partial pressure in the tundish 3 is detected and compared with the following results: the oxygen partial pressure (Po2) in the tundish 3 before use was 4%, and the oxygen partial pressure (Po2) in the tundish after use was 0.7%; the steel water sample [ N ] in the tundish 3 is tested, 3PPM is added to the [ N ] before use compared with the former process, and 0PPM is added to the [ N ] after use compared with the former process.
It should be understood by those skilled in the art that the above embodiments are only for illustrating the present invention and are not to be used as a limitation of the present invention, and that changes and modifications to the above described embodiments are within the scope of the claims of the present invention as long as they are within the spirit and scope of the present invention.
Claims (12)
1. The utility model provides an automatic control system that continuous casting overall process prevents molten steel oxidation, links to respectively on the hookup location between mouth of a river and the long mouth of a river under the ladle, on the pouring basket, its characterized in that: the device comprises a long water gap gas seal pipeline connected to the connecting position, a tundish purging and gas seal pipeline connected to the tundish, and a tundish purging gas pipeline connected to the tundish;
a gas mixing chamber is communicated between the tundish purging and gas sealing pipeline and the tundish purging gas pipeline;
the automatic control system also comprises a control terminal which is used for controlling the long water gap gas seal pipeline, the tundish purging and gas seal pipeline and the tundish purging gas pipeline.
2. The automatic control system for preventing molten steel from being oxidized in the whole continuous casting process according to claim 1, characterized in that: argon is adopted for the long nozzle gas seal pipeline and the tundish purging and gas seal pipeline; the tundish purging gas pipeline adopts natural gas.
3. The automatic control system for preventing molten steel from being oxidized in the whole continuous casting process according to claim 2, wherein: the long nozzle gas seal pipeline comprises a first gas conveying pipe, and a first regulating valve, a first cut-off valve and a first flowmeter are sequentially arranged on the first gas conveying pipe along the gas conveying direction; and/or
Middle package sweeps and gas seal pipeline includes the gaseous conveyer pipe of second, be equipped with second governing valve, second trip valve and second flowmeter in proper order along gas conveying direction on the gaseous conveyer pipe of second, the gaseous conveyer pipe of second with gas mixing chamber intercommunication, gas mixing chamber pass through the gas pipeline with middle package intercommunication.
4. The automatic control system for preventing molten steel from being oxidized in the whole continuous casting process according to claim 2, wherein: middle package sweeps the gas pipeline and includes third gas delivery pipe, be equipped with third governing valve, third trip valve and third flow meter in proper order along gas conveying direction on the third gas delivery pipe, third gas delivery pipe with the gas mixing chamber intercommunication, the gas mixing chamber pass through the gas pipeline with middle package intercommunication.
5. An automatic control method for preventing molten steel from being oxidized in the whole continuous casting process is characterized in that: the tundish purging and gas sealing pipeline and the tundish purging gas pipeline are controlled by the control terminal in the system according to any one of claims 1 to 4, so that automatic tundish purging and gas sealing control is realized;
and controlling the long nozzle gas seal pipeline to realize the automatic control of the ladle long nozzle gas seal.
6. The automatic control method for preventing molten steel from being oxidized in the whole continuous casting process according to claim 5, wherein the automatic control of the tundish purge and the gas seal comprises:
blowing argon into the tundish by using the tundish blowing and air sealing pipeline after preheating of the tundish is finished and before pouring is prepared, and replacing air in the tundish;
when argon is blown in, the tundish blowing gas pipeline blows natural gas into the tundish, and the air which is not fully replaced is consumed by combustion in the tundish, so that the air in the tundish is fully replaced;
and when the pouring of the tundish is started, after a covering agent is thrown on the surface of the molten steel in the tundish, automatically switching the amount of argon for blowing to the amount of argon for gas sealing, and closing the purging gas pipeline of the tundish until the pouring of the tundish is finished.
7. The automatic control method for preventing molten steel from being oxidized in the whole continuous casting process according to claim 6, wherein: the amount of argon for blowing is 3000-8000 l/min, and the pressure is 0.6-0.8 MPa; and/or the amount of argon for air sealing is 1000-3000 l/min, and the pressure is 0.6-0.8 MPa.
8. The automatic control method for preventing molten steel from being oxidized in the whole continuous casting process according to claim 7, wherein: the natural gas amount is 3-5% of the argon gas amount for blowing.
9. The automatic control method for preventing oxidation of molten steel throughout continuous casting according to any one of claims 6 to 8, wherein the automatic control of tundish purge and gas seal further comprises the steps of:
1) setting the amount of argon for blowing and the amount of argon for gas sealing on the control terminal, setting the amount of natural gas according to 3-5% of the amount of argon for blowing, and selecting an automatic mode;
2) when the preheating of the tundish is finished, after the control terminal gives a preheating finishing signal, a second cut-off valve in the tundish purging and gas seal pipeline is automatically opened, and a second regulating valve in the tundish purging and gas seal pipeline regulates the flow to a set value of the amount of argon for blowing according to a second flowmeter in the tundish purging and gas seal pipeline;
3) meanwhile, a third cut-off valve in the tundish purging gas pipeline is automatically opened, a third regulating valve in the tundish purging gas pipeline regulates the flow to a set value of the natural gas amount according to a third flow meter in the tundish purging gas pipeline, and the tundish purging is started;
4) when the tundish starts to pour, the molten steel in the tundish is weighed to be more than or equal to 15-20 tons, and after a covering agent is added to the surface of the molten steel in the tundish, the third cut-off valve and the third regulating valve are automatically closed;
5) meanwhile, the second regulating valve regulates the flow to a set value of the argon amount for gas seal according to the second flowmeter, the tundish blowing is finished, and the gas seal is started;
6) and when the pouring of the tundish is finished, weighing the molten steel in the tundish is less than or equal to 10 tons, automatically closing the second stop valve and the second regulating valve, and finishing the gas seal.
10. The automatic control method for preventing molten steel from being oxidized in the whole continuous casting process according to claim 9, wherein: in the step 4), the covering agent is added before the first furnace of the tundish is started to be poured and the argon purging is closed;
the covering agent is added into the first furnace of the tundish according to the weight of 1-1.5% of the rated molten steel of the tundish, and then added according to the weight of 0.1-0.2% of the molten steel of each furnace of the tundish;
and when molten steel is exposed on the surface of the molten steel in the tundish, supplementing the covering agent at the exposed position.
11. The automatic control method for preventing molten steel from being oxidized in the whole continuous casting process according to claim 5, wherein the automatic control of the gas seal of the ladle long nozzle comprises:
before pouring of the tundish is started, argon gas flow for gas sealing is set on the control terminal, an automatic mode is selected, and when the rotary arm carrying the ladle reaches a pouring position, the long nozzle gas sealing pipeline blows the argon gas flow for gas sealing into the connecting position of the long nozzle and the upper and lower nozzles of the ladle for gas sealing.
12. The automatic control method for preventing molten steel from being oxidized in the whole continuous casting process according to claim 11, wherein the automatic control of the gas seal of the ladle shroud further comprises the steps of:
s1, before pouring of the tundish is started, setting argon flow for air sealing on the control terminal, and selecting an automatic mode;
s2, when the rotating arm carrying the ladle reaches the pouring position, a first cut-off valve in the long nozzle gas seal pipeline is automatically opened, a first regulating valve in the long nozzle gas seal pipeline regulates the flow to a set value of argon flow for gas seal according to a first flow meter in the long nozzle gas seal pipeline, and the ladle long nozzle gas seal starts to be carried out;
s3, when the pouring of the tundish is finished and the rotary arm leaves the pouring position, the first cut-off valve is automatically closed, the rotary arm carries the next ladle to the pouring position, and the first cut-off valve is automatically opened;
and S4, circularly performing the steps S1 to S3 until a pouring end signal is input to the control terminal, and ending the air sealing of the ladle long nozzle.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010578468.4A CN113828748B (en) | 2020-06-23 | 2020-06-23 | Automatic control system and method for preventing molten steel from being oxidized in whole continuous casting process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010578468.4A CN113828748B (en) | 2020-06-23 | 2020-06-23 | Automatic control system and method for preventing molten steel from being oxidized in whole continuous casting process |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113828748A true CN113828748A (en) | 2021-12-24 |
| CN113828748B CN113828748B (en) | 2023-04-11 |
Family
ID=78963824
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010578468.4A Active CN113828748B (en) | 2020-06-23 | 2020-06-23 | Automatic control system and method for preventing molten steel from being oxidized in whole continuous casting process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113828748B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4062397A (en) * | 1976-03-16 | 1977-12-13 | Cashdollar Sr Robert E | Protection against oxidation of molten metal streams in continuous casting |
| JP2007260741A (en) * | 2006-03-29 | 2007-10-11 | Jfe Steel Kk | Method of starting continuous casting of molten steel |
| CN203330387U (en) * | 2013-06-11 | 2013-12-11 | 鞍钢股份有限公司 | Fire sealing device capable of preventing molten steel from secondary oxidation |
| CN206536025U (en) * | 2017-02-15 | 2017-10-03 | 唐山钢铁集团有限责任公司 | A kind of tundish cover of continuous casting tundish with Argon function |
| CN210587156U (en) * | 2019-07-16 | 2020-05-22 | 宝山钢铁股份有限公司 | Robot steel ladle pouring long nozzle with argon sealing device |
-
2020
- 2020-06-23 CN CN202010578468.4A patent/CN113828748B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4062397A (en) * | 1976-03-16 | 1977-12-13 | Cashdollar Sr Robert E | Protection against oxidation of molten metal streams in continuous casting |
| JP2007260741A (en) * | 2006-03-29 | 2007-10-11 | Jfe Steel Kk | Method of starting continuous casting of molten steel |
| CN203330387U (en) * | 2013-06-11 | 2013-12-11 | 鞍钢股份有限公司 | Fire sealing device capable of preventing molten steel from secondary oxidation |
| CN206536025U (en) * | 2017-02-15 | 2017-10-03 | 唐山钢铁集团有限责任公司 | A kind of tundish cover of continuous casting tundish with Argon function |
| CN210587156U (en) * | 2019-07-16 | 2020-05-22 | 宝山钢铁股份有限公司 | Robot steel ladle pouring long nozzle with argon sealing device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113828748B (en) | 2023-04-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112481551B (en) | Steel WB36V for power station and smelting and continuous casting production process thereof | |
| CN1621538A (en) | Production method for reducing and fining the high-carbon chromium bearing steel D-type impurity | |
| CN107234217B (en) | A kind of ar blowing refining method for producing SPHC steel grades | |
| CN111910040B (en) | Method for stably controlling oxidability of ultra-low carbon steel top slag | |
| CN102787202A (en) | Method for controlling nitrogen content of low nitrogen steel | |
| CN115433809B (en) | Steel smelting production method for high-strength prestressed steel strand with excellent drawing performance | |
| CN108893576A (en) | The smelting process of welding rod steel H08A | |
| CN111485052A (en) | Smelting method of 97-grade ultrahigh-strength cord steel | |
| CN113828748B (en) | Automatic control system and method for preventing molten steel from being oxidized in whole continuous casting process | |
| CN109161639B (en) | Smelting process of DT4 magnetic pole and magnetic yoke steel of main magnet of 250MeV superconducting cyclotron | |
| CN112981032B (en) | Method for smelting low-titanium high-carbon chromium bearing steel by high-titanium molten iron | |
| CN108555273B (en) | Method for improving ladle self-opening rate by bottom blowing inert gas | |
| CN214270950U (en) | LF stove is concise blows slag face deoxidation device | |
| CN113774188A (en) | Premelted refining slag, preparation method and application of premelted refining slag in refining of high-purity manganese 25 ultrahigh-manganese steel material | |
| CN208293030U (en) | A kind of ladle bottom blowing air brick volume control device | |
| CN214349596U (en) | Long-acting anti-blocking protection device for blowing argon at bottom of intermediate frequency furnace and casting ladle | |
| CN115780753A (en) | Bottom argon blowing control device of continuous casting ladle turret and method for removing impurities through soft blowing | |
| CN212293649U (en) | HIsmelt technology composite desulfurization recarburization device | |
| CN107838388A (en) | A kind of continuous casting production Argon metallurgical plant and argon gas control method | |
| CN217677621U (en) | Molten iron desulphurization blowing system | |
| CN220361982U (en) | Novel ladle for realizing automatic casting and self-guiding of molten steel without drainage sand | |
| CN111136248B (en) | Intelligent control method and intelligent supply system for magnesium melt pouring pipe protective gas | |
| CN111041154B (en) | Slag-iron separation device on slag conveyor and use method thereof | |
| CN109128120B (en) | Method for improving self-casting rate of X7Ni9 steel | |
| CN214517476U (en) | Powder spraying device for improving ingot casting defects and ingot casting equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |