CN111577685B - Electric arc furnace hydraulic system control method - Google Patents
Electric arc furnace hydraulic system control method Download PDFInfo
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- CN111577685B CN111577685B CN202010454772.8A CN202010454772A CN111577685B CN 111577685 B CN111577685 B CN 111577685B CN 202010454772 A CN202010454772 A CN 202010454772A CN 111577685 B CN111577685 B CN 111577685B
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- hydraulic
- hydraulic pump
- pressure
- control system
- electric arc
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
- F15B11/17—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors using two or more pumps
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/024—Pressure relief valves
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B19/00—Testing; Calibrating; Fault detection or monitoring; Simulation or modelling of fluid-pressure systems or apparatus not otherwise provided for
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/04—Special measures taken in connection with the properties of the fluid
- F15B21/042—Controlling the temperature of the fluid
- F15B21/0423—Cooling
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/08—Servomotor systems incorporating electrically operated control means
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
- F27B3/10—Details, accessories, or equipment peculiar to hearth-type furnaces
- F27B3/28—Arrangement of controlling, monitoring, alarm or the like devices
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
Abstract
The invention relates to a control method of a hydraulic system of an electric arc furnace, wherein a pressure transmitter is arranged on a system oil circuit of a hydraulic station, the pressure transmitter monitors the pressure of the system oil circuit, when the pressure value reaches 11.5-12.5 MPa, the pressure transmitter feeds back to the hydraulic control system, and the hydraulic control system sends out a signal for controlling the stop of a hydraulic pump motor corresponding to a hydraulic pump; when the pressure value reaches 9.5-10.5 MPa, the pressure transmitter feeds back to the hydraulic control system, and the hydraulic control system sends out a signal for controlling the starting of the hydraulic pump motor. By the control method, under the condition of meeting the power required by the work of the electric arc furnace, the hydraulic pump motor can work intermittently, so that energy can be saved, and the problem of power consumption caused by long-time continuous work of the hydraulic pump motor in the prior art is solved.
Description
Technical Field
The invention relates to the technical field of electric arc furnace control, in particular to a method for controlling a hydraulic system of an electric arc furnace.
Background
The electro-fused corundum is prepared by melting industrial alumina or calcined alumina serving as a raw material in an electric arc furnace at a high temperature, is an important raw material for preparing high-grade refractory materials, and is also widely used in the abrasive industry. The fused corundum has the advantages of simple process, short flow, low product cost and the like and excellent performance, the raw materials can be used as aggregate and matrix to produce unshaped refractory materials, and the fused corundum brick is widely applied to high-temperature kilns and high-temperature metallurgical equipment. According to different technological requirements, different kinds of fused corundum such as fused brown corundum, fused sub-white corundum, fused compact corundum, fused plate corundum and the like can be obtained.
The electric arc furnace for smelting corundum is also called ore furnace, and uses ore with high resistivity as raw material, and the lower portion of electrode is generally buried in furnace material in the course of working, and its heating principle is: the heat generated by the resistance of the furnace burden when the current passes through the furnace burden is utilized, and the heat generated by the electric arc between the electrode and the furnace burden is also utilized; and is therefore also referred to as an arc or resistance furnace.
The electric arc furnace mainly comprises a furnace body, a transformer, a voltage and current regulating system, an electrode rod hydraulic lifting system, a hydraulic furnace tilting system and the like. The whole equipment is provided with a set of hydraulic station which comprises three 22KW plunger pumps (hydraulic pumps), only one pump is started in normal operation, and one pump is started and the other pump is standby during furnace tilting operation; the hydraulic station is also provided with a 2.2kw cooling circulation pump. The hydraulic station is equipped with 4 accumulator cylinders for pressure storage.
In the smelting process, the electrode rod hydraulic lifting system always works, so that a hydraulic pump needs to be started during operation, and the pressure needs to be kept at about 12 MPa.
According to long-term observation, the up-and-down swing range of the electrode of the electric melting furnace is not large, the use pressure and the oil flow are small, only the pressure required in the furnace tilting process is slightly large, but the furnace tilting process is a few minutes. The motor of the hydraulic pump is 22KW, even if the hydraulic pump is in an unloading state most of the time, the motor is kept on all the time, and even if the load is only half of the load when the pressure is loaded, the electricity consumption per hour is over 14 degrees. The oil temperature of the hydraulic pump can be increased immediately after the hydraulic pump runs for a long time, a circulating pump needs to be started for a long time, and the motor of the circulating pump is 2.2KW and is electrified at 2 degrees per hour. The whole hydraulic station consumes more than 17 degrees of electricity per hour. Each electric arc furnace is used for smelting for 20 hours every day, and the electric energy consumption is about 340 degrees probably. Each device is started for 300 days in a year, and the total power consumption is about 96000 degrees.
The invention patent of the publication number CN101782321B discloses an automatic electrode adjusting device of a direct current electric arc furnace and a control method thereof, which achieve the purpose of energy saving by adjusting and controlling the arc voltage and the arc flow, but still solve the problem that the prior hydraulic system control mode has large power consumption.
Disclosure of Invention
The invention aims to provide a method for controlling a hydraulic system of an electric arc furnace, which aims to solve the problem of high power consumption of the existing hydraulic system control mode.
In order to achieve the purpose, the invention adopts the following technical scheme:
a control method of a hydraulic system of an electric arc furnace is characterized in that a pressure transmitter is arranged on a system oil circuit of a hydraulic station, the pressure transmitter monitors the pressure of the system oil circuit, when the pressure value reaches 11.5-12.5 MPa, the pressure transmitter feeds back to the hydraulic control system, and the hydraulic control system sends out a signal for controlling the stop of a hydraulic pump motor corresponding to a hydraulic pump; when the pressure value reaches 9.5-10.5 MPa, the pressure transmitter feeds back to the hydraulic control system, and the hydraulic control system sends out a signal for controlling the starting of the hydraulic pump motor.
Further, when the pressure value reaches 12MPa, the pressure transmitter feeds back to the hydraulic control system, and the hydraulic control system sends out a signal for controlling the stop of a hydraulic pump motor corresponding to the hydraulic pump; when the pressure value reaches 10MPa, the pressure transmitter feeds back to the hydraulic control system, and the hydraulic control system sends out a signal for controlling the starting of the hydraulic pump motor.
Further, a hydraulic pump motor corresponding to one hydraulic pump in the hydraulic station is started or stopped according to the judgment of the pressure value, and the hydraulic pump is marked as a first hydraulic pump.
Further, when the furnace cover lifting condition of the electric arc furnace is met, the hydraulic control system stops judging the signal fed back by the pressure transmitter, and the stopping time is 100-140 seconds, so that the output pressure can meet the pressure value required by the furnace cover lifting and is more than 12.8 MPa.
Furthermore, the hydraulic station also comprises a second hydraulic pump, and when furnace tilting operation is carried out, two hydraulic pumps are required to be started; when the furnace tilting condition is met, rotating a furnace tilting button, and sequentially starting a first hydraulic pump and a second hydraulic pump, wherein the starting time interval of the first hydraulic pump and the second hydraulic pump is 3 seconds; after 100-140 seconds, the first hydraulic pump and the second hydraulic pump are sequentially closed; in the tilting operation process, the hydraulic control system stops judging the signal fed back by the pressure transmitter.
Further, after starting for 120 seconds, the first hydraulic pump and the second hydraulic pump are sequentially closed.
Furthermore, the first hydraulic pump and the second hydraulic pump are plunger pumps, and the rated pressure is 13 MPa.
Further, the unloading valve of the hydraulic pump is opened while the hydraulic pump motor is stopped.
The invention has the beneficial effects that:
the hydraulic system pressure value is monitored by arranging the pressure transmitter, after the pressure value exceeds the set pressure upper limit, a signal is fed back and the hydraulic pump motor is controlled to stop, when the system pressure value is reduced to reach the set pressure lower limit, the hydraulic pump motor is automatically started, and the hydraulic pump works to boost. By the control method, the hydraulic pump motor works intermittently, and the machine can be stopped for about 30 to 40 minutes in each period, so that the energy-saving effect is achieved; the hydraulic pump is not directly continuous work, then the circulating pump that plays the cooling effect also need not work all the time, further improves energy-conserving effect.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below.
The embodiment of the invention comprises the following steps:
a control method for the hydraulic system of electric arc furnace features that a pressure transmitter is arranged on the system oil line of hydraulic station. The hydraulic station is also in the prior art and comprises three hydraulic pumps, namely a first hydraulic pump, a second hydraulic pump and a third hydraulic pump, which all adopt plunger pumps, and the rated pressure is 13 MPa. In normal operation of the arc furnace, the electrode is lifted, the first hydraulic pump is operated, and the power of the corresponding hydraulic pump motor is 22 KW. According to the invention, the pressure transmitter is additionally arranged, the pressure signal is fed back to the hydraulic control system, and the hydraulic control system controls the starting or stopping of the hydraulic pump motor, so that the hydraulic pump motor can intermittently work, namely the first hydraulic pump intermittently works. The set position of the pressure transmitter is explained as follows: the oil way is arranged between the energy storage oil cylinder and the hydraulic pump; or can also be arranged on the output oil path of the energy storage oil cylinder.
The pressure transmitter monitors the pressure of an oil path of the system, when the pressure value reaches 12MPa, the pressure transmitter feeds back to the hydraulic control system, and the hydraulic control system sends out a signal for controlling the stop of a hydraulic pump motor corresponding to the first hydraulic pump; the hydraulic control system comprises a PLC controller. When the pressure value is reduced to 10MPa, the pressure transmitter feeds back to the hydraulic control system, and the hydraulic control system sends out a signal for controlling the starting of the hydraulic pump motor, so that the pressure of the system is increased. The hydraulic pump pressure is restored to 12MPa, and a time of about 20 seconds is required.
When the motor of the hydraulic pump stops, the unloading valve of the first hydraulic pump is opened for a few seconds, such as 5 to 6 seconds, so that the damage of mechanical inertia to the hydraulic pump and the mechanical structure of the motor when the motor stops can be reduced.
Because the pressure and the oil flow required by the electrode lifting drive of the electric arc furnace are small, the hydraulic pump motor works intermittently, so that the system pressure is in the range of 10-12 MPa, and the power requirement of the electrode lifting action can be met. The cycle period is about 30-40 minutes, namely the hydraulic pump motor can be stopped for such a long time each time. The first hydraulic pump does not work continuously for a long time, so that a circulating pump motor of the hydraulic station can work intermittently without working all the time. In conclusion, compared with the working mode of the existing system, the control method can save the electric energy by 280 degrees every day.
When the furnace cover lifting condition of the electric arc furnace is met, the hydraulic control system stops judging the signal fed back by the pressure transmitter, and the stopping time is 120 seconds. That is, the pressure transmitter can continue to monitor, but does not judge the pressure signal, the starting and stopping actions of the hydraulic pump motor are not influenced by the pressure signal of the system, and the judgment principle can be set through the PLC. In the time period, the system pressure can meet the pressure value of more than 12.8MPa required by the lifting of the furnace cover. If the judgment on the signal fed back by the pressure transmitter is not stopped, the pressure provided by the first hydraulic pump cannot exceed 12MPa and the pressure within the range of 10-12 MPa, so that the pressure required by the lifting of the furnace cover cannot be met. If the furnace cover lifting condition of the electric arc furnace is met, the hydraulic pump motor corresponding to the first hydraulic pump is in a stop state, the hydraulic pump motor is started, if the hydraulic pump motor is in a working state, the hydraulic pump motor continues working, so that the system pressure rises, and the process of boosting and furnace cover lifting actions can be completed by the system pressure within the time range of 120 seconds.
When the furnace tilting operation is carried out, the requirement can be met only by opening the two hydraulic pumps when the large flow is needed. When the furnace tilting condition is met, the furnace tilting button is rotated, the second hydraulic pump is in a standby state, the first hydraulic pump and the second hydraulic pump are started in sequence, the starting time interval of the first hydraulic pump and the second hydraulic pump is 3 seconds, and in order to prevent the two hydraulic pump motors from being started simultaneously, the influence of overlarge current on the system stability is caused.
After 120 seconds, the first hydraulic pump and the second hydraulic pump are sequentially closed; during the tilting operation, the hydraulic control system also stops judging the signal fed back by the pressure transmitter, because the upper limit of the system pressure is not required to be controlled to be 12MPa in the process. After the 120 seconds, the hydraulic control system judges the pressure signal fed back by the pressure transmitter, and the pressure of the control system is within the range of 10-12 MPa, so that the aim of saving electricity is fulfilled.
In other embodiments, the upper and lower limits of the monitored pressure may also be adjusted, for example, the upper limit of the pressure may also be set to 11.5 or 12.5MPa, when the system pressure reaches the upper limit, the pressure transmitter feeds back to the hydraulic control system, and the hydraulic control system sends a signal for controlling the stop of the hydraulic pump motor corresponding to the hydraulic pump. The lower pressure limit can be adjusted, the lower pressure limit can be set to 9.5 or 10.5MPa, when the system pressure reaches the lower limit, the pressure transmitter feeds back to the hydraulic control system, and the hydraulic control system sends out a signal for controlling the starting of the hydraulic pump motor.
In other embodiments, the stop monitoring time of the pressure transmitter can be set to be 100 seconds or 140 seconds during the operation of the furnace cover according to different electric arc furnaces or different production requirements.
In other embodiments, the first hydraulic pump and the second hydraulic pump may be sequentially turned off after 100 seconds or 140 seconds during the tilting operation, or the time value within the range may be set according to the difference of the electric arc furnace or the difference of the production requirement.
The present invention is not limited to the above-mentioned preferred embodiments, and any other products in various forms can be obtained by anyone in the light of the present invention, but any changes in the shape or structure thereof, which have the same or similar technical solutions as those of the present application, fall within the protection scope of the present invention.
Claims (7)
1. A method for controlling a hydraulic system of an electric arc furnace is characterized by comprising the following steps: the method comprises the following steps that a pressure transmitter is arranged on a system oil path of a hydraulic station, the pressure transmitter monitors the pressure of the system oil path, when the pressure value reaches 11.5-12.5 MPa, the pressure transmitter feeds back to a hydraulic control system, and the hydraulic control system sends out a signal for controlling the stop of a hydraulic pump motor corresponding to a hydraulic pump; when the pressure value reaches 9.5-10.5 MPa, the pressure transmitter feeds back to the hydraulic control system, the hydraulic control system sends out a signal for controlling the starting of the hydraulic pump motor, when the furnace cover lifting condition of the electric arc furnace is met, the hydraulic control system stops judging the signal fed back by the pressure transmitter, and the stopping time is 100-140 seconds, so that the output pressure can meet the pressure value required by the lifting of the furnace cover and is more than 12.8 MPa.
2. The electric arc furnace hydraulic system control method according to claim 1, characterized in that: when the pressure value reaches 12MPa, the pressure transmitter feeds back to the hydraulic control system, and the hydraulic control system sends out a signal for controlling the stop of a hydraulic pump motor corresponding to the hydraulic pump; when the pressure value reaches 10MPa, the pressure transmitter feeds back to the hydraulic control system, and the hydraulic control system sends out a signal for controlling the starting of the hydraulic pump motor.
3. The electric arc furnace hydraulic system control method according to claim 1 or 2, characterized in that: and starting or stopping a hydraulic pump motor corresponding to one hydraulic pump in the hydraulic station according to the judgment of the pressure value, wherein the hydraulic pump is marked as a first hydraulic pump.
4. The electric arc furnace hydraulic system control method according to claim 3, characterized in that: the hydraulic station also comprises a second hydraulic pump, and when furnace tilting operation is carried out, the two hydraulic pumps need to be started; when the furnace tilting condition is met, rotating a furnace tilting button, and sequentially starting a first hydraulic pump and a second hydraulic pump, wherein the starting time interval of the first hydraulic pump and the second hydraulic pump is 3 seconds; after 100-140 seconds, the first hydraulic pump and the second hydraulic pump are sequentially closed; in the tilting operation process, the hydraulic control system stops judging the signal fed back by the pressure transmitter.
5. The electric arc furnace hydraulic system control method according to claim 4, characterized in that: and after starting for 120 seconds, the first hydraulic pump and the second hydraulic pump are sequentially closed.
6. The electric arc furnace hydraulic system control method according to claim 4, characterized in that: the first hydraulic pump and the second hydraulic pump are plunger pumps, and the rated pressure is 13 MPa.
7. The electric arc furnace hydraulic system control method according to claim 1 or 2, characterized in that: and opening an unloading valve of the hydraulic pump while the motor of the hydraulic pump stops.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010454772.8A CN111577685B (en) | 2020-05-26 | 2020-05-26 | Electric arc furnace hydraulic system control method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010454772.8A CN111577685B (en) | 2020-05-26 | 2020-05-26 | Electric arc furnace hydraulic system control method |
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| CN111577685A CN111577685A (en) | 2020-08-25 |
| CN111577685B true CN111577685B (en) | 2022-03-15 |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0183284A1 (en) * | 1984-10-04 | 1986-06-04 | Pennsylvania Engineering Corporation | Arc furnace burner control method and apparatus |
| JPS61153375A (en) * | 1984-12-26 | 1986-07-12 | 新日本製鐵株式会社 | Method of operating hydraulic drive for arc furnace |
| CN103321974A (en) * | 2012-03-24 | 2013-09-25 | 何荣志 | Novel energy-saving hydraulic station |
| CN104728208A (en) * | 2015-03-17 | 2015-06-24 | 西南石油大学 | High-power hydraulic driving fracturing-pump pump station system |
| CN204461038U (en) * | 2014-12-30 | 2015-07-08 | 朱兴发 | Electric arc furnaces broken Electrode real-time online automatic detection and control device |
| CN108827012A (en) * | 2018-08-14 | 2018-11-16 | 沈阳创联工业技术有限公司 | Oil plant flue gas of heating furnace desulfurization air-introduced machine PLC frequency-converting speed-governing control system |
-
2020
- 2020-05-26 CN CN202010454772.8A patent/CN111577685B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0183284A1 (en) * | 1984-10-04 | 1986-06-04 | Pennsylvania Engineering Corporation | Arc furnace burner control method and apparatus |
| JPS61153375A (en) * | 1984-12-26 | 1986-07-12 | 新日本製鐵株式会社 | Method of operating hydraulic drive for arc furnace |
| CN103321974A (en) * | 2012-03-24 | 2013-09-25 | 何荣志 | Novel energy-saving hydraulic station |
| CN204461038U (en) * | 2014-12-30 | 2015-07-08 | 朱兴发 | Electric arc furnaces broken Electrode real-time online automatic detection and control device |
| CN104728208A (en) * | 2015-03-17 | 2015-06-24 | 西南石油大学 | High-power hydraulic driving fracturing-pump pump station system |
| CN108827012A (en) * | 2018-08-14 | 2018-11-16 | 沈阳创联工业技术有限公司 | Oil plant flue gas of heating furnace desulfurization air-introduced machine PLC frequency-converting speed-governing control system |
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| CN111577685A (en) | 2020-08-25 |
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