CN112280932A - Process detection system for smelting molten state of scrap steel in electric arc furnace - Google Patents
Process detection system for smelting molten state of scrap steel in electric arc furnace Download PDFInfo
- Publication number
- CN112280932A CN112280932A CN202011325221.8A CN202011325221A CN112280932A CN 112280932 A CN112280932 A CN 112280932A CN 202011325221 A CN202011325221 A CN 202011325221A CN 112280932 A CN112280932 A CN 112280932A
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- Prior art keywords
- arc furnace
- electric arc
- transformer
- voltage
- voltage side
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- 238000010891 electric arc Methods 0.000 title claims abstract description 76
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 25
- 239000010959 steel Substances 0.000 title claims abstract description 25
- 238000003723 Smelting Methods 0.000 title claims abstract description 21
- 238000000034 method Methods 0.000 title claims abstract description 8
- 238000001514 detection method Methods 0.000 title abstract description 6
- 238000002844 melting Methods 0.000 claims abstract description 24
- 230000008018 melting Effects 0.000 claims abstract description 24
- 238000006073 displacement reaction Methods 0.000 claims abstract description 8
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 12
- 238000004458 analytical method Methods 0.000 claims description 4
- 238000004364 calculation method Methods 0.000 claims description 4
- 238000004904 shortening Methods 0.000 abstract description 3
- 238000005266 casting Methods 0.000 abstract description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 6
- 229910002804 graphite Inorganic materials 0.000 description 5
- 239000010439 graphite Substances 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000009628 steelmaking Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000011179 visual inspection Methods 0.000 description 1
Images
Classifications
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/52—Manufacture of steel in electric furnaces
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/52—Manufacture of steel in electric furnaces
- C21C2005/5288—Measuring or sampling devices
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
-
- 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
- Y02P10/25—Process efficiency
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
- Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
Abstract
The invention relates to a process detection system for an electric arc furnace smelting scrap steel melting state, which belongs to the field of metallurgical casting and comprises an electric arc furnace transformer, wherein a high-voltage side voltage transformer, a high-voltage circuit breaker, a high-voltage side zero-sequence current transformer and a series reactor are arranged on the high-voltage side of the electric arc furnace transformer; the low-voltage side of the electric arc furnace transformer is provided with a low-voltage side current transformer and an electrode lifting upright post, and the electrode lifting upright post is connected with an electrode and a displacement sensor. The invention reduces the electric energy quality fluctuation and load impact of the electric arc furnace and ensures the balance degree of the input power in the furnace; has important guiding significance for improving the smelting power factor of the electric arc furnace and shortening the smelting period of the electric arc furnace.
Description
Technical Field
The invention belongs to the field of metallurgical casting, and relates to a process detection system for the melting state of scrap steel smelted by an electric arc furnace.
Background
When the existing steelmaking electric arc furnace is produced, the melting state of scrap steel in the furnace is detected, most of the scrap steel depends on the manual experience of operators, and observation and judgment are carried out through visual inspection through a furnace door; or a noise detector is arranged in front of the furnace, and the melting state in the furnace is judged according to the change of the noise decibel; or the reference judgment is carried out by collecting the current of the power supply grid of the electric arc furnace according to the fluctuation of the current.
Because the production environment of the steelmaking electric arc furnace is severe, the randomness of the source of scrap steel raw materials is large, the load impact change of the electric arc furnace is large during melting, the interference on the power quality of a power grid is large, and an operator can have errors by observing and judging according to experience; an electric furnace production site belongs to a high-dust environment, and a sound collecting device is frequently blocked in use, so that inaccurate noise decibel detection is caused; the change of carbon spraying amount of the electric furnace has larger interference fluctuation to the electrode current.
The factors cause the unbalance of melting power in the electric arc furnace, the adjustment of electrode power is lagged, the smelting period of the electric arc furnace is prolonged, the erosion of refractory materials on the furnace wall is uneven, and the stable smelting production of the electric arc furnace is influenced.
Disclosure of Invention
In view of the above, the present invention provides a system for detecting the melting state of scrap steel in an electric arc furnace.
In order to achieve the purpose, the invention provides the following technical scheme:
a process detection system for the melting state of scrap steel smelted by an electric arc furnace comprises an electric arc furnace transformer, wherein a high-voltage side voltage transformer, a high-voltage circuit breaker, a high-voltage side zero sequence current transformer and a series reactor are arranged on the high-voltage side of the electric arc furnace transformer; the low-voltage side of the electric arc furnace transformer is provided with a low-voltage side current transformer and an electrode lifting upright post, and the electrode lifting upright post is connected with an electrode and a displacement sensor.
Further, an iron core current transformer is arranged on the body of the electric arc furnace transformer.
And the system controller is connected with a high-voltage side voltage transformer, a high-voltage circuit breaker, a high-voltage side zero-sequence current transformer, a series reactor, an iron core current transformer, a low-voltage side current transformer and a displacement sensor.
Further, the electric arc furnace transmits a power supply to the series reactor through the high-voltage circuit breaker, and then transmits the smelted electric energy to the electrode of the electric arc furnace through the electric arc furnace transformer, so that the electric energy required by smelting of the electric arc furnace is provided.
Further, the high-voltage side voltage transformer and the high-voltage side zero sequence current transformer respectively detect the voltage unbalance rate, the total voltage distortion rate and the zero sequence current value change rate of the electric arc furnace.
Further, under the condition that the high-voltage circuit breaker is disconnected, a gear switch of the series reactor is adjusted, a gear signal of the series reactor is detected, and the magnitude of a series reactance value of the circuit is calculated.
Further, the system controller collects the voltage unbalance rate, the zero sequence current value change rate and the iron core grounding current value change rate of the electric arc furnace transformer and the current unbalance rate and the working position change value of the electrode, carries out comprehensive analysis and calculation, judges the melting state of the scrap steel in the electric arc furnace, adjusts the output power of the electric arc furnace transformer and dynamically adapts to the melting rate of the scrap steel.
The invention has the beneficial effects that: the invention reduces the electric energy quality fluctuation and load impact of the electric arc furnace and ensures the balance degree of the input power in the furnace; has important guiding significance for improving the smelting power factor of the electric arc furnace and shortening the smelting period of the electric arc furnace.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the means of the instrumentalities and combinations particularly pointed out hereinafter.
Drawings
For the purposes of promoting a better understanding of the objects, aspects and advantages of the invention, reference will now be made to the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a view showing a structure of a process detecting system for detecting a molten state of scrap in electric arc furnace smelting.
Reference numerals: 1-high voltage side voltage transformer, 2-high voltage breaker, 3-high voltage side zero sequence current transformer, 4-series reactor, 5-arc furnace transformer, 6-iron core current transformer, 7-low voltage side current transformer, 8-electrode lifting column, 9 is displacement sensor, 10-electrode, 11-system controller.
Detailed Description
The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention in a schematic way, and the features in the following embodiments and examples may be combined with each other without conflict.
Wherein the showings are for the purpose of illustrating the invention only and not for the purpose of limiting the same, and in which there is shown by way of illustration only and not in the drawings in which there is no intention to limit the invention thereto; to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.
The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there is an orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "rear", etc., based on the orientation or positional relationship shown in the drawings, it is only for convenience of description and simplification of description, but it is not an indication or suggestion that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes, and are not to be construed as limiting the present invention, and the specific meaning of the terms may be understood by those skilled in the art according to specific situations.
As shown in FIG. 1, a process detecting system for detecting the melting state of scrap steel smelted in an electric arc furnace, wherein a set of voltage transformers and a set of zero sequence current transformers are arranged on the high voltage side of the electric arc furnace and used for respectively detecting the voltage unbalance rate, the total voltage distortion rate and the zero sequence current value change rate of the electric arc furnace; detecting a gear signal of a series reactor of the electric arc furnace, and calculating the magnitude of a series reactance value of a line; arranging an iron core current transformer on a transformer body of the transformer, and detecting the change rate of the iron core grounding current value of the transformer; arranging a group of current transformers on the low-voltage side of the transformer, and detecting the current unbalance rate and the total current distortion rate of the graphite electrode; arranging a displacement sensor in a lifting upright post of the graphite electrode to detect a working position change value of the graphite electrode; by acquiring the voltage unbalance rate, the zero sequence current value change rate and the iron core grounding current value change rate of the electric arc furnace and the changes of the current unbalance rate of the electrode and the electrode working position value, a system controller performs comprehensive analysis and calculation to judge the melting state of the scrap steel in the electric arc furnace, adjust the output power of the transformer and dynamically adapt to the melting rate of the scrap steel; the electric energy quality fluctuation and load impact of the electric arc furnace are reduced, and the balance degree of input power in the electric arc furnace is ensured; has important guiding significance for improving the smelting power factor of the electric arc furnace and shortening the smelting period of the electric arc furnace.
The electric arc furnace transmits power to a series reactor 4 through a high-voltage circuit breaker 2, and transmits smelted electric energy to an electric arc furnace electrode 7 through an electric arc furnace transformer 5 to provide electric energy required by electric arc furnace smelting;
arranging a high-voltage side voltage transformer 1 and a high-voltage side zero sequence current transformer 3 on the high-voltage side of an electric arc furnace transformer 5, and respectively detecting the voltage unbalance rate, the total voltage distortion rate and the zero sequence current value change rate of the electric arc furnace;
under the condition that the high-voltage circuit breaker 2 is disconnected, adjusting a gear switch of the series reactor 4, detecting a gear signal of the series reactor 4, and calculating the magnitude of a series reactance value of a line;
an iron core current transformer 6 is arranged in the body of the electric arc furnace transformer 5, and the change rate of the iron core grounding current value of the electric arc furnace transformer 5 is detected;
arranging a group of low-voltage side current transformers 7 on the low-voltage side of the electric arc furnace transformer 5, and detecting the current unbalance rate and the total current distortion rate of the graphite electrode 10;
a displacement sensor 9 is arranged in the electrode lifting upright post 8 and is used for detecting the working position change value of the graphite electrode 10;
the system controller 11 collects the voltage unbalance rate, the zero sequence current value change rate and the iron core grounding current value change rate of the electric arc furnace transformer 5, the current unbalance rate and the working position change value of the electrode 10, performs comprehensive analysis and calculation, judges the melting state of the scrap steel in the electric arc furnace, adjusts the output power of the electric arc furnace transformer 5, and dynamically adapts to the melting rate of the scrap steel.
Finally, the above embodiments are only intended to illustrate the technical solutions of the present invention and not to limit the present invention, and although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions, and all of them should be covered by the claims of the present invention.
Claims (7)
1. The utility model provides a process detecting system of scrap steel melting state is smelted to electric-arc furnace which characterized in that: the high-voltage side zero-sequence current transformer is characterized by comprising an electric arc furnace transformer, wherein a high-voltage side voltage transformer, a high-voltage circuit breaker, a high-voltage side zero-sequence current transformer and a series reactor are arranged on the high-voltage side of the electric arc furnace transformer; the low-voltage side of the electric arc furnace transformer is provided with a low-voltage side current transformer and an electrode lifting upright post, and the electrode lifting upright post is connected with an electrode and a displacement sensor.
2. The system for detecting the melting state of scrap steel for electric arc furnace smelting according to claim 1, wherein: and an iron core current transformer is arranged on the body of the electric arc furnace transformer.
3. The system for detecting the melting state of scrap steel for electric arc furnace smelting according to claim 1, wherein: the system controller is connected with a high-voltage side voltage transformer, a high-voltage circuit breaker, a high-voltage side zero sequence current transformer, a series reactor, an iron core current transformer, a low-voltage side current transformer and a displacement sensor.
4. The system for detecting the melting state of scrap steel for electric arc furnace smelting according to claim 1, wherein: the electric arc furnace transmits a power supply to the series reactor through the high-voltage circuit breaker, and transmits smelted electric energy to the electrode of the electric arc furnace through the electric arc furnace transformer to provide the electric energy required by the electric arc furnace smelting.
5. The system for detecting the melting state of scrap steel for electric arc furnace smelting according to claim 1, wherein: and the high-voltage side voltage transformer and the high-voltage side zero sequence current transformer are used for respectively detecting the voltage unbalance rate, the total voltage distortion rate and the zero sequence current value change rate of the electric arc furnace.
6. The system for detecting the melting state of scrap steel for electric arc furnace smelting according to claim 1, wherein: under the condition that the high-voltage circuit breaker is disconnected, a gear switch of the series reactor is adjusted, a gear signal of the series reactor is detected, and the magnitude of a series reactance value of the circuit is calculated.
7. The system for detecting the melting state of scrap steel for electric arc furnace smelting according to claim 1, wherein: the system controller collects the voltage unbalance rate, the zero sequence current value change rate, the iron core grounding current value change rate, the current unbalance rate of the electrode and the working position change value of the electric arc furnace transformer, carries out comprehensive analysis and calculation, judges the melting state of the scrap steel in the electric arc furnace, adjusts the output power of the electric arc furnace transformer and dynamically adapts to the melting rate of the scrap steel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011325221.8A CN112280932A (en) | 2020-11-23 | 2020-11-23 | Process detection system for smelting molten state of scrap steel in electric arc furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011325221.8A CN112280932A (en) | 2020-11-23 | 2020-11-23 | Process detection system for smelting molten state of scrap steel in electric arc furnace |
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| Publication Number | Publication Date |
|---|---|
| CN112280932A true CN112280932A (en) | 2021-01-29 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202011325221.8A Pending CN112280932A (en) | 2020-11-23 | 2020-11-23 | Process detection system for smelting molten state of scrap steel in electric arc furnace |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113915999A (en) * | 2021-09-17 | 2022-01-11 | 中冶赛迪工程技术股份有限公司 | Intermediate frequency induction electric arc furnace and smelting control method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09280736A (en) * | 1996-04-09 | 1997-10-31 | Toyota Motor Corp | Melting-down detecting method in melting furnace |
| JPH09300054A (en) * | 1996-05-13 | 1997-11-25 | Nippon Steel Corp | Device and method for detecting invasion of molten metal in pouring system continuous casting, and method for shutting off molten metal |
| JPH10245690A (en) * | 1997-03-04 | 1998-09-14 | Nikko Kinzoku Kk | Detection of abnormality of electrolytic smelting and abnormality detection system for executing the same |
| JP2002322518A (en) * | 2000-04-18 | 2002-11-08 | Mitsubishi Materials Corp | Method and system for monitoring furnace condition in separating furnace, method and system for operating matte smelting facility, and program and recording medium for recording this program |
| CN201828130U (en) * | 2009-08-27 | 2011-05-11 | 钢铁普蓝特克股份有限公司 | Electric arc melting equipment |
| CN104965949A (en) * | 2015-06-30 | 2015-10-07 | 东北大学 | Method for monitoring faults in smelting process of multimode magnesia electrical smelting furnace |
-
2020
- 2020-11-23 CN CN202011325221.8A patent/CN112280932A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09280736A (en) * | 1996-04-09 | 1997-10-31 | Toyota Motor Corp | Melting-down detecting method in melting furnace |
| JPH09300054A (en) * | 1996-05-13 | 1997-11-25 | Nippon Steel Corp | Device and method for detecting invasion of molten metal in pouring system continuous casting, and method for shutting off molten metal |
| JPH10245690A (en) * | 1997-03-04 | 1998-09-14 | Nikko Kinzoku Kk | Detection of abnormality of electrolytic smelting and abnormality detection system for executing the same |
| JP2002322518A (en) * | 2000-04-18 | 2002-11-08 | Mitsubishi Materials Corp | Method and system for monitoring furnace condition in separating furnace, method and system for operating matte smelting facility, and program and recording medium for recording this program |
| CN201828130U (en) * | 2009-08-27 | 2011-05-11 | 钢铁普蓝特克股份有限公司 | Electric arc melting equipment |
| CN104965949A (en) * | 2015-06-30 | 2015-10-07 | 东北大学 | Method for monitoring faults in smelting process of multimode magnesia electrical smelting furnace |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113915999A (en) * | 2021-09-17 | 2022-01-11 | 中冶赛迪工程技术股份有限公司 | Intermediate frequency induction electric arc furnace and smelting control method |
| CN113915999B (en) * | 2021-09-17 | 2024-01-23 | 中冶赛迪工程技术股份有限公司 | Medium frequency induction arc furnace and smelting control method |
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