CN217562118U - Multifunctional selective bleed-out alarm controller for induction furnace - Google Patents
Multifunctional selective bleed-out alarm controller for induction furnace Download PDFInfo
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- CN217562118U CN217562118U CN202221392408.4U CN202221392408U CN217562118U CN 217562118 U CN217562118 U CN 217562118U CN 202221392408 U CN202221392408 U CN 202221392408U CN 217562118 U CN217562118 U CN 217562118U
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Abstract
The utility model relates to a multifunctional selective bleed-out alarm controller for an induction furnace, which relates to the field of bleed-out alarm of the induction furnace and comprises a power supply module, an alarm module, a detection module and a switch selection module; the power supply module comprises a transformer and a rectifier and supplies power to the alarm module, the detection module and the switch selection module; the alarm module is used for monitoring the current or the voltage in the controller; the detection module comprises a side electrode and a bottom electrode and is used for detecting the leakage current of the furnace lining; the switch selection module is set to be a multifunctional selection switch, the fixed end of the multifunctional selection switch is electrically connected to one end of the bottom electrode, which is connected with the negative electrode of the voltage output end of the power supply module, and the movable end of the multifunctional selection switch comprises a grounding end, a ground-free testing end and a probe testing end; the grounding end is grounded, the no-ground test end is unloaded, and the probe test end is electrically connected with one end of the open-circuit probe; the method and the device have the effect of distinguishing false alarm and false alarm failure problems of the system of the induction furnace under different working conditions.
Description
Technical Field
The application relates to the technical field of electric induction furnace steel leakage alarming, in particular to a multifunctional selective steel leakage alarming controller for an electric induction furnace.
Background
The through-furnace bleed-out of the furnace body of the induction furnace refers to that molten steel contained in the furnace body penetrates through a refractory furnace lining and permeates to an induction coil of the furnace body. After the steel is tapped, the molten steel permeates into the inductance coil to cause serious accidents, if the steel is light, the inductance coil is burnt, and if the steel is heavy, the cooling water in the inductance coil is flushed into the molten steel in the furnace to cause the explosion of the furnace body.
The possible reasons for the breakout of the furnace are as follows: the furnace lining is eroded and thinned by molten steel for a long time, and the molten steel cannot bear the pressure of the molten steel, so that the molten steel penetrates through the furnace lining; the furnace lining is quenched and heated to generate cracks, and the molten steel penetrates through the induction coil along the cracks; when the furnace is charged, the large burden impacts the wall of the furnace lining to damage the furnace lining, and molten steel penetrates to the induction coil through the damaged part of the furnace lining.
For the problem of bleed-out of a furnace, equipment manufacturers are matched with a bleed-out alarm device at present. The traditional steel leakage alarm device is realized by adopting direct current injection and detecting the leakage current of a furnace lining between a bottom electrode and a side electrode. Specifically, the method comprises the following steps: arranging a furnace bottom probe from the furnace bottom to contact molten steel to serve as a bottom electrode, and grounding the bottom electrode; and arranging a stainless steel side net between the outer circle of the furnace lining and the coil permanent pouring layer, and arranging another furnace bottom probe from the side net lead to the furnace bottom to be used as a side electrode. And finally, leading the bottom electrode and the side electrode to a breakout alarm controller to serve as two input electrodes, detecting whether the furnace body passes through the furnace and breakout through detecting leakage current between the two electrodes by the breakout alarm controller, and reflecting the furnace lining from the leakage current after the furnace lining is thinned due to normal consumption. The working principle of the traditional steel leakage alarm is shown in figure 1. The traditional steel leakage alarm is mainly determined by the situation that the complex and changeable field situation often causes false alarm and missing alarm. For example: the lead of the side net or the side electrode 5 is damaged or grounded due to other reasons, and false alarm is caused because the bottom electrode 4 is grounded; or further: the bottom electrode 4 is open or is not completely contacted with the molten steel, and the alarm cannot be given out even if the molten steel permeates into the inductance coil, so that the alarm is missed.
Disclosure of Invention
The utility model aims at providing a multi-functional selection bleed-out alarm control ware for induction furnace.
The application provides a multi-functional selection breakout alarm controller for induction furnace adopts following technical scheme:
a multifunctional selective breakout alarm controller for an induction furnace comprises a power supply module, an alarm module, a detection module and a switch selection module;
the power supply module comprises a transformer and a rectifier and is used for converting alternating current into direct current and supplying power to the alarm module, the detection module and the switch selection module;
the alarm module is used for monitoring the current or voltage in the controller, comparing the current or voltage with a preset value, and alarming when the current or voltage exceeds the preset value;
the detection module comprises a side electrode and a bottom electrode and is used for detecting the magnitude of leakage current of the furnace lining, one end of the side electrode is electrically connected to the positive electrode of the voltage output end of the power supply module, and the other end of the side electrode is electrically connected with a stainless steel side net arranged between the excircle of the furnace lining and the coil permanent pouring layer; one end of the bottom electrode is electrically connected to the negative electrode of the voltage output end of the power supply module, and the other end of the bottom electrode is arranged at the bottom of the furnace and contacts molten steel;
the switch selection module is set to be a multifunctional selection switch, the fixed end of the multifunctional selection switch is electrically connected to one end of the bottom electrode connected with the negative electrode of the voltage output end of the power supply module, and the movable end of the multifunctional selection switch comprises a grounding end, an ungrounded test end and a probe test end; the grounding end is grounded, the no-ground test end is unloaded, and the probe test end is electrically connected with one end of the open-circuit probe.
By adopting the technical scheme, in the using process, the working principle is that the use condition of the furnace lining is still reflected by detecting the leakage current between the molten steel and the side electrode led out by the side net through direct current injection; different from the traditional controller, the utility model discloses multi-functional selection switch has been add. The additional arrangement of the multifunctional selection switch can discriminate the false alarm and the false alarm failure of the alarm controller. The multifunctional selector switch is provided with a grounding end, a ground-free testing end and a probe testing end which respectively correspond to a grounding operation gear, a ground-free testing function gear and a probe testing function gear. The discrimination process, namely the principle, is as follows: 1. when the leakage current suddenly increases (exceeds a set value), the switch can be selected to be a function level for testing without earth, if the leakage current is still large, the problem of steel leakage through a furnace is proved to occur, and if the leakage current suddenly decreases (returns to a normal value), the side net or the side electrode lead is possibly grounded for some reason. Because the former normal use of putting into operation selects ground connection operation shelves to also ground connection bottom electrode, so in case the side electrode also ground connection then alarm system forms the return circuit, triggers the warning, and its real molten steel does not permeate side net department this moment, belongs to the wrong report to police. When the switch is selected to test the functional level without ground, the grounding point of the bottom electrode is disconnected, and at the moment, if the leakage current returns to a normal value, false alarm caused by the grounding of the side net or the side electrode can be confirmed. 2. The alarm is put into use to select a grounding operation gear, if the leakage current still does not rise along with the normal use of the furnace lining, the switch can select a probe test function gear, and then the temporary detection probe is inserted into the molten steel from the furnace outlet to replace the bottom electrode, so the leakage current is still small, the furnace lining is better maintained, the leakage current is small, if the leakage current is suddenly increased, the circuit of the bottom electrode is open-circuited, possibly the bottom electrode is disconnected at a certain position, or the bottom electrode probe is contacted with the molten steel. It should be noted that during normal operation of the alarm, the grounded operating mode must be selected. Since the molten steel in the induction coil is induced with a levitation voltage, it is necessary to protect the operational safety of the operating firemen by grounding the bottom electrode. The ground-free test function file and the probe test function file are only used for discriminating false alarm and false alarm of the system, and cannot be used and operated all the time. The multifunctional selector switch is additionally arranged, so that the problems of false alarm and missed alarm of the system under different working conditions in the working process of the induction furnace can be screened out to the maximum extent.
Preferably, the multifunctional selector switch is a single-pole three-throw switch.
By adopting the technical scheme, the single-pole triple-throw switch is simple in structure, low in cost and easy to realize.
Preferably, the alarm module comprises a voltage comparator and a sliding rheostat, one input end of the voltage comparator is electrically connected to the movable end of the sliding rheostat, and two fixed ends of the sliding rheostat are connected in series between the positive electrode of the voltage output end of the power supply module and the side electrode; the other input end of the voltage comparator is electrically connected to the output end of a reference voltage.
By adopting the technical scheme, the voltage in the main loop is collected through the comparator and compared with the preset voltage, so that the current of the main loop of the controller is judged.
Preferably, the alarm module further comprises an alarm element electrically connected to an output terminal of the voltage comparator.
By adopting the technical scheme, the working personnel can be reminded to check in time by observing the alarm element.
Preferably, the alarm module comprises an ammeter, and the ammeter is connected in series between the positive electrode of the voltage output end of the power supply module and the side electrode.
By adopting the technical scheme, the state of the alarm controller can be checked by checking the indicating number of the ammeter, so that the state of the induction furnace is judged.
Preferably, the alarm module includes a voltmeter and a resistor, the resistor is connected in series between the positive electrode of the voltage output end of the power supply module and the side electrode, and the voltmeter is electrically connected to two ends of the resistor.
By adopting the technical scheme, the state of the alarm controller can be checked by checking the number indicated by the voltmeter, so that the state of the induction furnace is judged.
Preferably, the multifunctional selective breakout alarm controller further comprises a current limiting resistor R connected in series between the sliding rheostat and the side electrode.
By adopting the technical scheme, if the resistance of the furnace lining is 0, for example, steel penetration occurs, the circuit has the risk of large short circuit, the current-limiting resistor R can play a role in clamping voltage, and the circuit is maintained not to be burnt.
Preferably, the multifunctional selective breakout alarm controller further comprises a filter inductor L and a bypass capacitor C, the filter inductor L is connected in series between the current limiting resistor R and the side electrode, one end of the bypass capacitor C is electrically connected to one end of the filter inductor L far away from the side electrode, and the other end of the bypass capacitor C is electrically connected to the negative electrode of the voltage output end of the power supply module.
By adopting the technical scheme, because the coil in the furnace lining is provided with the alternating current, when steel leakage or fault occurs, a high-voltage alternating current can be induced on the side electrode, so that an LC filter circuit can be formed by the filter inductor L and the bypass capacitor C, the alternating current which is possibly led from the resistance of the furnace lining from the side electrode can be reduced, and the use of an alarm module is not easily influenced; the potential at the connecting point between the bypass capacitor C and the filter inductor L can be reduced by changing the inductance value of the filter inductor L and the capacitance value of the bypass capacitor C, so that the purpose of voltage reduction can be achieved.
In summary, the present application includes at least one of the following beneficial technical effects:
the multifunctional selection switch is additionally arranged on the basis of the original traditional breakout alarm, so that the problems of false alarm and missing alarm of the system under different working conditions in the working process of the induction furnace can be screened to the maximum extent.
Drawings
FIG. 1 is a working principle of a traditional breakout alarm in the embodiment of the application;
FIG. 2 is a working schematic diagram of a multifunctional selective breakout alarm in the embodiment of the application;
reference numerals: 1. a power supply module; 2. an alarm module; 3. a switch selection module; 4. a bottom electrode; 5. a side electrode; 6. an open circuit detection bar; 7. the equivalent resistance of the furnace lining.
Detailed Description
The present application is described in further detail below with reference to figures 1-2.
Referring to fig. 1, it is a circuit diagram of the working principle of the traditional steel leakage alarm. The traditional breakout alarm comprises a power supply module 1, an alarm module 2 and a detection module. The power supply module 1 comprises a transformer and a rectifier, wherein the transformer changes the value of alternating voltage to enable the voltage value to meet the power supply requirement of the alarm; the rectifier converts alternating current to direct current. The controller has a bottom electrode 4 and a side electrode 5 in its circuit, respectively, and the bottom electrode 4 and the side electrode 5 are used for monitoring the change of the resistance value of the electric furnace to determine whether the steel leakage occurs. In the schematic diagram of the circuit, a component between the bottom electrode 4 and the side electrode 5 is a furnace lining equivalent resistor 7. The alarm module 2 is mainly used for monitoring the current change on the electric furnace body by acquiring the voltage in the circuit through the comparator, and alarming when abnormality occurs. In order to observe specific current change more conveniently, an ammeter is also connected in series in the circuit.
The traditional steel leakage alarm is mainly determined by the fact that the complex and variable field conditions often cause the situations of false alarm and missed alarm.
For example: the lead of the side net or the side electrode 5 is damaged or grounded due to other reasons, and false alarm is caused because the bottom electrode 4 is grounded; or further: the bottom electrode 4 is open or is not completely contacted with the molten steel, and the alarm cannot be given out even if the molten steel permeates into the inductance coil, so that the alarm is missed.
In this embodiment: referring to fig. 2, the multifunctional selective breakout alarm controller for the induction furnace comprises a power supply module 1, an alarm module 2, a detection module and a switch selection module 3. The power supply module 1, the alarm module 2 and the detection module are not much different from the traditional alarm, and a switch selection module 3 is mainly added.
The power supply module 1 comprises a transformer and a rectifier and is used for converting alternating current into direct current which is stably output and meets the requirements and supplying power to the alarm module 2, the detection module and the switch selection module 3.
And the alarm module 2 is used for monitoring the current or the voltage in the controller, comparing the current or the voltage with a preset value, and giving an alarm when the current or the voltage exceeds the preset value. The alarm module 2 adopts a voltage comparator and a slide rheostat, the voltage comparator collects the voltage in the main loop through the slide rheostat and compares the voltage with a reference voltage, and a comparison result is output. When the circuit is abnormal, the output end of the voltage comparator outputs an alarm signal, so that the current of the main loop of the controller can be indirectly judged. In order to remind the working personnel to check alarm information more timely, the output end of the voltage comparator can be electrically connected with an alarm element, and the alarm element can be an LED lamp or a buzzer or other elements playing an alarm role.
Besides the current of the main loop can be checked through the ammeter, the change of the voltage on the resistor in the circuit can be indirectly observed through setting the voltmeter and the resistor, so that the change of the current in the circuit is judged, and then the state of the induction furnace is judged.
The detection module comprises a side electrode 5 and a bottom electrode 4, and is used for detecting the size of the leakage current of the furnace lining, and the corresponding schematic diagram is used for detecting the equivalent resistance 7 of the furnace lining. One end of the side electrode 5 is electrically connected to the positive pole of the voltage output terminal of the power supply module 1, and the ammeter is connected in series between the side electrode 5 and the positive pole of the voltage output terminal of the power supply module 1. The other end of the side electrode 5 is electrically connected to one end of the lining equivalent resistance 7. One end of the bottom electrode 4 is electrically connected to the negative electrode of the voltage output end of the power supply module 1, and the other end of the furnace lining equivalent resistor 7 is electrically connected.
The switch selection module 3 is configured as a multifunctional selection switch, and the multifunctional selection switch in the present application may be configured as a single-pole three-throw switch or other switches capable of implementing the same function. The multifunctional selector switch comprises a fixed end and three movable ends. The fixed end of the multifunctional selection switch is electrically connected to one end of the bottom electrode 4 connected with the negative electrode of the voltage output end of the power supply module 1; the movable end of the multifunctional selection switch comprises a grounding end, a no-ground test end and a probe test end; the grounding end is grounded, the no-ground test end is unloaded, and the probe test end is electrically connected with one end of the open-circuit probe 6. Wherein, the open-circuit detecting rod 6 is arranged on the furnace platform and can be temporarily inserted into the molten steel from the furnace mouth to replace the bottom electrode 4.
The controller also comprises a current limiting resistor R connected in series between the slide rheostat and the side electrode 5, if the lining resistance is 0, such as steel penetration, the circuit has a large short circuit risk, and the current limiting resistor R can play a role in clamping voltage to maintain the circuit not to be burnt.
Since the coil in the furnace is ac, a higher voltage ac may be induced in the side electrode 5 when a breakout or a fault occurs. Therefore, the multifunctional selective breakout alarm controller further comprises a filter inductance L and a bypass capacitor C, the filter inductance L is connected in series between the current limiting resistor R and the side electrode 5, one end of the bypass capacitor C is electrically connected to one end of the filter inductance L remote from the side electrode 5, and the other end of the bypass capacitor C is electrically connected to the negative electrode of the voltage output terminal of the power supply module 1. An LC filter circuit can be formed by the filter inductor L and the bypass capacitor C, and the alternating current which is possibly led from the side electrode 5 to the furnace lining equivalent resistor 7 can be reduced, so that the use of the alarm module 2 is not easily influenced; the potential at the connecting point between the bypass capacitor C and the filter inductor L can be reduced by changing the inductance value of the filter inductor L and the capacitance value of the bypass capacitor C, so that the purpose of voltage reduction can be achieved.
The implementation principle of the embodiment of the application is as follows: the main working principle of the device is that the leakage current between the molten steel and the side electrode 5 led out by the side net is detected through direct current injection to reflect the use condition of the furnace lining. Different from the traditional controller, the utility model discloses multi-functional selection switch has been add. The additional arrangement of the multifunctional selection switch can discriminate the false alarm and the false alarm failure of the alarm controller.
The discrimination process, namely the principle, is as follows:
1. when the leakage current suddenly increases (exceeds a set value), the switch can be selected to be a function level for testing without earth, if the leakage current is still large, the problem of steel leakage through a furnace is proved to occur, and if the leakage current suddenly decreases (returns to a normal value), the side net or the lead of the side electrode 5 is possibly grounded due to some reason.
Because the bottom electrode 4 is grounded when the grounding operation gear is normally used originally, once the side electrode 5 is grounded, the alarm system forms a loop to trigger alarm, and at the moment, the molten steel does not permeate into the side net, so that the false alarm is realized. When the switch is selected to test the functional level ungrounded, the grounding of the bottom electrode 4 is disconnected, and if the leakage current returns to a normal value, it can be verified that this is indeed a false alarm due to the grounding of the side grid or the side electrode 5.
2. The alarm is put into use to select a grounding operation gear, if the leakage current still does not rise along with the normal use of the furnace lining, the switch can select a probe test function gear, then the temporary detection probe is inserted into the molten steel from the furnace outlet to replace the bottom electrode 4, so the leakage current is still small, the maintenance of the furnace lining is better, the leakage current is smaller, if the leakage current is increased suddenly, the circuit of the bottom electrode 4 is open-circuited, possibly the bottom electrode 4 is disconnected at a certain position, and possibly a probe of the bottom electrode 4 is in contact with the molten steel.
It should be noted that the ground operating range must be selected for normal operation of the alarm. Since the molten steel in the induction coil is induced with a levitation voltage, it is necessary to protect the operational safety of the operating firemen by grounding through the bottom electrode 4. The no-ground test function file and the probe test function file are only used for discriminating false alarm and false alarm of the system and cannot be used and operated all the time.
The embodiments of the present invention are preferred embodiments of the present application, and the protection scope of the present application is not limited thereby, wherein like parts are denoted by like reference numerals. Therefore: equivalent changes in structure, shape and principle of the present application shall be covered by the protection scope of the present application.
Claims (8)
1. A multifunctional selective breakout alarm controller for an induction furnace is characterized by comprising a power supply module (1), an alarm module (2), a detection module and a switch selection module (3);
the power supply module (1) comprises a transformer and a rectifier and is used for converting alternating current into direct current and supplying power to the alarm module (2), the detection module and the switch selection module (3);
the alarm module (2) is used for monitoring the current or voltage in the controller, comparing the current or voltage with a preset value, and alarming when the current or voltage exceeds the preset value;
the detection module comprises a side electrode (5) and a bottom electrode (4) and is used for detecting the leakage current of the furnace lining, one end of the side electrode (5) is electrically connected to the positive electrode of the voltage output end of the power supply module (1), and the other end of the side electrode is electrically connected with a stainless steel side net arranged between the excircle of the furnace lining and the coil permanent pouring layer; one end of the bottom electrode (4) is electrically connected to the negative electrode of the voltage output end of the power supply module (1), and the other end of the bottom electrode is arranged at the bottom of the furnace and contacts molten steel;
the switch selection module (3) is set to be a multifunctional selection switch, the fixed end of the multifunctional selection switch is electrically connected to one end, connected with the negative electrode of the voltage output end of the power supply module (1), of the bottom electrode (4), and the movable end of the multifunctional selection switch comprises a grounding end, a ground-free testing end and a probe testing end; the grounding end is grounded, the no-ground test end is unloaded, and the probe test end is electrically connected with one end of an open-circuit probe (6).
2. The multifunctional selective breakout alarm controller for an induction furnace according to claim 1, wherein the multifunctional selective switch is a single-pole triple-throw switch.
3. A multifunctional selective breakout alarm controller for an induction furnace according to claim 1, characterized in that the alarm module (2) comprises a voltage comparator with one of its input terminals electrically connected to the movable terminal of the slide rheostat with its two stationary terminals connected in series between the positive pole of the voltage output of the power supply module (1) and the side electrode (5); the other input end of the voltage comparator is electrically connected to the output end of a reference voltage.
4. A multifunctional selective breakout alarm controller for an induction furnace according to claim 3, characterized in that the alarm module (2) further comprises an alarm element electrically connected to the output of the voltage comparator.
5. A multifunctional selective breakout alarm controller for an induction furnace according to claim 3, characterized in that the alarm module (2) comprises an ammeter connected in series between the positive pole of the voltage output of the power supply module (1) and the side electrode (5).
6. A multifunctional selective breakout alarm controller for an induction furnace according to claim 3, characterized in that the alarm module (2) comprises a voltmeter and a resistor, the resistor being connected in series between the positive pole of the voltage output of the power supply module (1) and the side electrode (5), the voltmeter being electrically connected to both ends of the resistor.
7. A multifunctional selective breakout alarm controller for an induction furnace according to claim 5, characterized in that it further comprises a current limiting resistor R connected in series between the sliding varistor and the side electrode (5).
8. The multifunctional selective breakout warning controller for an induction furnace according to claim 7, characterized in that it further comprises a filter inductance L connected in series between the current limiting resistor R and the side electrode (5), and a bypass capacitor C, one end of which is electrically connected to the end of the filter inductance L remote from the side electrode (5), the other end of which is electrically connected to the negative pole of the voltage output of the power supply module (1).
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| CN202221392408.4U CN217562118U (en) | 2022-05-25 | 2022-05-25 | Multifunctional selective bleed-out alarm controller for induction furnace |
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| CN202221392408.4U CN217562118U (en) | 2022-05-25 | 2022-05-25 | Multifunctional selective bleed-out alarm controller for induction furnace |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116124389A (en) * | 2023-04-19 | 2023-05-16 | 合智熔炼装备（上海）有限公司 | Crucible leakage detection pre-judging device and detection method thereof |
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2022
- 2022-05-25 CN CN202221392408.4U patent/CN217562118U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116124389A (en) * | 2023-04-19 | 2023-05-16 | 合智熔炼装备（上海）有限公司 | Crucible leakage detection pre-judging device and detection method thereof |
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