CN104034157A - Runout alarm circuit of crucible electric induction furnace - Google Patents
Runout alarm circuit of crucible electric induction furnace Download PDFInfo
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- CN104034157A CN104034157A CN201410311785.4A CN201410311785A CN104034157A CN 104034157 A CN104034157 A CN 104034157A CN 201410311785 A CN201410311785 A CN 201410311785A CN 104034157 A CN104034157 A CN 104034157A
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Abstract
The invention provides a runout alarm circuit of a crucible electric induction furnace and belongs to the electronic technical field. The runout alarm circuit of the crucible electric induction furnace solves the problem that runout of a crucible electric induction furnace in the prior art cannot be detected. The runout alarm circuit of the crucible electric induction furnace comprises a molten steel electrode on the electric induction furnace, an internal cooling electrode in a cooling tank, an external cooling electrode outside a cooling pond, and an induction coil L, a lead is arranged in a molten steel furnace of the crucible electric induction furnace and connected with the molten steel electrode. The runout alarm circuit further comprises a conversion switch K, a switch K1, a switch K2, a switch K3, a switch K4, a switch K5, a bell DL, an alarm lamp, a contact KM, a transformer T and a switch ampere meter A1, the conversion switch K comprises two incoming line ends and two outgoing ends, and the two ends of the conversion switch K are connected with the live wire and the null line of a 220V alternating current power source respectively. The runout alarm circuit of the crucible electric induction furnace can detect leakage of the crucible electric induction furnace in time and guarantee reliable operation of the crucible electric induction furnace.
Description
Technical field
The invention belongs to electronic technology field, relate to a kind of crucible electric induction furnace runout warning circuit.
Background technology
Crucible electric induction furnace operation principle is based on electromagnetic induction and heating effect of current principle.When alternating current passes through induction coil, at coil, produce alternating magnetic field around, in stove, conductive material produces induced potential under action of alternating magnetic field. at furnace charge surface certain depth, form electric current.Furnace charge is by eddy heating for heating fusing.If fusing is ferrous metal material in stove. be in the effect that molten steel in high-intensity magnetic field is subject to electromagnetic force and produce strong motion.Magnetic field is called function composite by electromagnetic stirring to this effect of molten steel.
Runout warning device is the important protective device of crucible electric induction furnace, once there is runout, should be able to accurately report to the police, and prevents from that molten steel from spilling from furnace lining to burn out the collide generation of serious accidents such as setting off an explosion of the copper pipe of induction coil and high temperature liquid iron and inductor cooling water.Contingency and seriousness due to this accident generation, for guaranteeing operation that crucible electric induction furnace is safe and reliable and workman's personal safety, how to design electric furnace and fail to report the reliability and safety of alarm device in improving that crucible electric induction furnace is actual and using and become the problem that user studies, for effectively preventing the generation of this security incident, it is necessary on crucible electric induction furnace, installing runout warning device.
Summary of the invention
The present invention is directed to existing technology and have the problems referred to above, proposed a kind of crucible electric induction furnace runout warning circuit, this crucible electric induction furnace runout warning circuit can be hunted leak to crucible electric induction furnace in time, ensures electric furnace reliability service.
The present invention realizes by following technical proposal: a kind of crucible electric induction furnace runout warning circuit, it is characterized in that, comprise the molten steel utmost point being arranged on electric furnace, be arranged on the cooling interior utmost point in cooler bin, be arranged on the cooling outer utmost point and induction coil L outside cooling bay, in the molten steel stove of crucible electric induction furnace, be provided with lead-in wire, described lead-in wire is connected with the molten steel utmost point, this crucible electric induction furnace runout warning circuit also comprises change-over switch K, K switch 1, K switch 2, K switch 3, K switch 4, K switch 5, electric bell DL, alarm lamp, contactor KM, transformer T and switching current Table A 1, described change-over switch K comprises two ends of incoming cables and two leading-out terminals, two ends of described change-over switch K respectively with the live wire of 220V AC power, zero line connects, the leading-out terminal of described change-over switch K is connected with normal open switch KM-1 one end of relay K M, the other end of described relay K M normal open switch KM-1 is connected with one end of electric bell DL, another leading-out terminal of described change-over switch K is connected with the other end of electric bell DL, described change-over switch K is connected with the connected node of relay K M normal open switch and normal open switch one end of switching current Table A, the other end of described switching current Table A normal open switch is connected with coil one end of relay K M, the normal open switch KM-2 of described relay K M is connected in parallel on the two ends of switching current Table A normal open switch, described switching current Table A normal open switch is connected with one end of the connected node of relay K M normal open switch KM-1 and the high voltage input of transformer T, the other end of described transformer T high voltage input is connected with the coil other end of relay K M1, and connected node is connected with the other end of electric bell DL, described alarm lamp is connected in parallel on electric bell DL two ends, two low-voltage outputs of described transformer T are connected with bridge rectifier, one end of described switching current Table A is connected with the cathode output end of bridge rectifier, the other end of described switching current Table A is connected with variable resistor R1, the other end of described variable resistor R is connected with K switch 5 one end, the other end of described K switch 5 is connected with the induction coil L in crucible electric induction furnace, the connected node of described variable resistor R1 and K switch 5 is connected with resistance R 2, one end of described K switch 4 is connected with one end of K switch 3, described resistance R 2 is connected on the connected node of K switch 4 and K switch 3, the other end of described K switch 3 is connected with the cooling interior utmost point, the other end of described K switch 4 is connected with the cooling outer utmost point, one end of described K switch 1 is connected with one end of K switch 2, the cathode output end of described bridge rectifier is connected with the connected node of K switch 2 with K switch 1, the other end ground connection of described K switch 1, the other end of described K switch 2 is connected with the molten steel utmost point.
Crucible electric induction furnace is normally worked, when staff suspects electric furnace runout, staff presses change-over switch K, 220V AC power is connected transformer T, transformer T carries out step-down by 22V high voltage, and by bridge rectifier, alternating current is made into low-voltage DC, provide safety to organize altogether voltage, safeguard work personnel's personal safety.When staff presses K switch 1 and K switch 5 simultaneously, detect whether ground connection of this crucible electric induction furnace runout warning circuit, can whether normally be connected with ground wire by sense switch K1, when staff presses K switch 1 and K switch 3 simultaneously, can detect the cooling interior utmost point and the ground connection that whether goes between, when staff presses K switch 1 and K switch 4 simultaneously, can detect whether ground connection of the cooling outer utmost point, when staff is to after this electric circuit inspection, can be to detecting the runout of crucible electric induction furnace, when staff presses K switch 2 and K switch 3, when if now electric furnace runout and molten steel flow in cooler bin, because molten steel has electric conductivity, now circuit forms loop, switching current Table A shows current values, switching current Table A has the characteristic of setting the automatic turn on-switch of current value, when the numerical value showing in switching current Table A is greater than zero, the normal open switch of switching current Table A is closed, engage relay KM, relay K M obtains electric, the normal open switch KM-1 of relay K M and normal open switch KM-2 are closed, alarm lamp is luminous, electric bell DL sounding, prove that runout phenomenon has appearred in crucible electric induction furnace, while molten steel has flow into cooler bin and has suffered, when should staff pressing K switch 2 and K switch 4, can detect molten steel and whether overflow cooler bin, when should staff pressing K switch 2 and K switch 5, can detect molten steel and whether drain to induction coil, by design and the operation of this circuit, can have a clear understanding of whether runout of crucible electric induction furnace, can know where judge molten steel has drained to, and is convenient to staff and sues and labours in time, avoids the generation of security incident simultaneously.
In above-mentioned crucible electric induction furnace runout warning circuit, between described change-over switch K and relay K M normal open switch KM-1, be in series with fusible link FU1, between described transformer T and bridge rectifier, be in series with fusible link FU2.Set up fusible link, while avoiding current overload, damage components and parts.
In above-mentioned crucible electric induction furnace runout warning circuit, between described bridge rectifier cathode output end and K switch 1 and the connected node of K switch 2, be in series with a Zener diode D and sampling resistor R3, described rectification circuit cathode output end is connected with the P utmost point of Zener diode D, the N utmost point of described Zener diode D is connected with one end of sampling resistor R3, and the other end of described sampling resistor R3 is connected with the connected node of K switch 2 with K switch 1.Set up Zener diode D and sampling resistor R3 can guarantee the stability of direct voltage output, thereby improve the reliability of this circuit.
In above-mentioned crucible electric induction furnace runout warning circuit, the cooling outer utmost point of described cooler bin is also connected with resistance R 4, resistance R 5, resistance R 6 and resistance R 7, one end of described resistance R 4, resistance R 5, resistance R 6 and resistance R 7 is connected with the cooling outer utmost point, other end ground connection.When crucible electric induction furnace runout, because the electric conductivity of molten iron tends to electric leakage, resistance eutral grounding can effectively be kept away to electricity, avoid causing casualties.
In above-mentioned crucible electric induction furnace runout warning circuit, described resistance R 4, resistance R 5, resistance R 6 and resistance R 7 are earth resistance, and resistance is identical.Improved and kept away electric effect, guaranteed crucible electric induction furnace reliability.
Compared with prior art, this has the following advantages for crucible electric induction furnace runout warning circuit: the stability that 1, can guarantee DC output voltage by Zener diode D and sampling resistor R3; 2, by the cooling outer earth resistance that resistance is set in extremely etc., resistance R 4, resistance R 5, resistance R 6 and resistance R 7, can effectively keep away electricity, and the electric leakage of avoiding electric furnace runout to cause causes casualties; 3, fusible link FU1 and fusible link FU2 can effectively protect this circuit, avoid the damage of components and parts.
Accompanying drawing explanation
Fig. 1 is circuit diagram of the present invention.
The specific embodiment
Be below specific embodiments of the invention by reference to the accompanying drawings, technical scheme of the present invention is further described, but the present invention be not limited to these embodiment.
As shown in Figure 1, a kind of crucible electric induction furnace runout warning circuit, comprise the molten steel utmost point (representing with a in the drawings) being arranged on electric furnace, be arranged on the cooling interior utmost point (representing with b in the drawings) in cooler bin and be arranged on the cooling outer utmost point (representing with c in the drawings) outside cooling bay, in the molten steel stove of crucible electric induction furnace, be provided with lead-in wire, lead-in wire is connected with the molten steel utmost point, this crucible electric induction furnace runout warning circuit also comprises change-over switch K, K switch 1, K switch 2, K switch 3, K switch 4, K switch 5, electric bell DL, alarm lamp, contactor KM, transformer T and switching current Table A 1, change-over switch K comprises two ends of incoming cables and two leading-out terminals, two ends of change-over switch K respectively with the live wire of 220V AC power, zero line connects, the leading-out terminal of change-over switch K is connected with one end of fusible link FU1, the other end of fusible link FU1 is connected with normal open switch KM-1 one end of relay K M, the other end of relay K M normal open switch KM-1 is connected with one end of electric bell DL, another leading-out terminal of change-over switch K is connected with the other end of electric bell DL, change-over switch K is connected with the connected node of relay K M normal open switch and normal open switch one end of switching current Table A, the other end of switching current Table A normal open switch is connected with coil one end of relay K M, the normal open switch KM-2 of relay K M is connected in parallel on the two ends of switching current Table A normal open switch, switching current Table A normal open switch is connected with one end of the connected node of relay K M normal open switch KM-1 and the high voltage input of transformer T, the other end of transformer T high voltage input is connected with the coil other end of relay K M1, and connected node is connected with the other end of electric bell DL, alarm lamp is connected in parallel on electric bell DL two ends, two low-voltage outputs of transformer T are connected with bridge rectifier, a low-voltage output of transformer T is connected with one end of fusible link FU2, the other end of fusible link FU2 is connected with the ac input end of bridge rectifier, another low-voltage output of transformer is connected with another ac input end of bridge rectifier, one end of switching current Table A is connected with the cathode output end of bridge rectifier, the other end of switching current Table A is connected with variable resistor R1, the other end of variable resistor R is connected with K switch 5 one end, the other end of K switch 5 connects and is connected with the induction coil L of crucible electric induction furnace, the connected node of variable resistor R1 and K switch 5 is connected with resistance R 2, one end of K switch 4 is connected with one end of K switch 3, resistance R 2 is connected on the connected node of K switch 4 and K switch 3, the other end of K switch 3 is connected with the cooling interior utmost point, the other end of K switch 4 is connected with the cooling outer utmost point, one end of K switch 1 is connected with one end of K switch 2, between bridge rectifier cathode output end and K switch 1 and the connected node of K switch 2, be in series with Zener diode D and sampling resistor R3, rectification circuit cathode output end is connected with the P utmost point of Zener diode D, the N utmost point of Zener diode D is connected with one end of sampling resistor R3, the other end of sampling resistor R3 is connected with the connected node of K switch 2 with K switch 1, the other end ground connection of K switch 1, the other end of K switch 2 is connected with the molten steel utmost point, the cooling outer utmost point of cooler bin is also connected with the earth resistance that four resistances are 10 Ω, be respectively resistance R 4, resistance R 5, resistance R 6 and resistance R 7, resistance R 4, resistance R 5, one end of resistance R 6 and resistance R 7 is connected with the cooling outer utmost point, other end ground connection is when crucible electric induction furnace leaks electricity, will be electrical ground, avoid causing casualties, guarantee crucible electric induction furnace reliability.
The operation principle of this crucible electric induction furnace runout warning circuit is as follows: crucible electric induction furnace is normally worked, when staff suspects electric furnace runout, staff presses change-over switch K, 220V AC power is connected transformer T, transformer T carries out step-down by 22V high voltage, and by bridge rectifier, alternating current is made into low-voltage DC, provide safety to organize altogether voltage, safeguard work personnel's personal safety.When staff presses K switch 1 and K switch 5 simultaneously, whether whether ground connection can be connected normal by sense switch K1 with ground wire to detect this crucible electric induction furnace runout warning circuit, when staff presses K switch 1 and K switch 3 simultaneously, can detect the cooling interior utmost point and the ground connection that whether goes between, when staff presses K switch 1 and K switch 4 simultaneously, can detect whether ground connection of the cooling outer utmost point, when staff is to after this electric circuit inspection, can be to detecting the runout of crucible electric induction furnace, when staff presses K switch 2 and K switch 3, when if now electric furnace runout and molten steel flow in cooler bin, because molten steel has electric conductivity, now circuit forms loop, switching current Table A shows current values, switching current Table A has the characteristic of setting the automatic turn on-switch of current value, when the numerical value showing in switching current Table A is greater than zero, the normal open switch of switching current Table A is closed, engage relay KM, relay K M obtains electric, the normal open switch KM-1 of relay K M and normal open switch KM-2 are closed, alarm lamp is luminous, electric bell DL sounding, prove that runout phenomenon has appearred in crucible electric induction furnace, while molten steel has flow into cooler bin and has suffered, when should staff pressing K switch 2 and K switch 4, can detect molten steel and whether overflow cooler bin, when should staff pressing K switch 2 and K switch 5, can detect molten steel and whether drain to induction coil, by design and the operation of this circuit, can have a clear understanding of whether runout of crucible electric induction furnace, can know where judge molten steel has drained to, and is convenient to staff and sues and labours in time, avoids the generation of security incident simultaneously.
Claims (5)
1. a crucible electric induction furnace runout warning circuit, it is characterized in that, comprise the molten steel utmost point being arranged on electric furnace, be arranged on the cooling interior utmost point in cooler bin, be arranged on the cooling outer utmost point and induction coil L outside cooling bay, in the molten steel stove of crucible electric induction furnace, be provided with lead-in wire, described lead-in wire is connected with the molten steel utmost point, this crucible electric induction furnace runout warning circuit also comprises change-over switch K, K switch 1, K switch 2, K switch 3, K switch 4, K switch 5, electric bell DL, alarm lamp, contactor KM, transformer T and switching current Table A 1, described change-over switch K comprises two ends of incoming cables and two leading-out terminals, two ends of described change-over switch K respectively with the live wire of 220V AC power, zero line connects, the leading-out terminal of described change-over switch K is connected with normal open switch KM-1 one end of relay K M, the other end of described relay K M normal open switch KM-1 is connected with one end of electric bell DL, another leading-out terminal of described change-over switch K is connected with the other end of electric bell DL, described change-over switch K is connected with the connected node of relay K M normal open switch and normal open switch one end of switching current Table A, the other end of described switching current Table A normal open switch is connected with coil one end of relay K M, the normal open switch KM-2 of described relay K M is connected in parallel on the two ends of switching current Table A normal open switch, described switching current Table A normal open switch is connected with one end of the connected node of relay K M normal open switch KM-1 and the high voltage input of transformer T, the other end of described transformer T high voltage input is connected with the coil other end of relay K M1, and connected node is connected with the other end of electric bell DL, described alarm lamp is connected in parallel on electric bell DL two ends, two low-voltage outputs of described transformer T are connected with bridge rectifier, one end of described switching current Table A is connected with the cathode output end of bridge rectifier, the other end of described switching current Table A is connected with variable resistor R1, the other end of described variable resistor R is connected with K switch 5 one end, the other end of described K switch 5 is connected with the induction coil L in crucible electric induction furnace, the connected node of described variable resistor R1 and K switch 5 is connected with resistance R 2, one end of described K switch 4 is connected with one end of K switch 3, described resistance R 2 is connected on the connected node of K switch 4 and K switch 3, the other end of described K switch 3 is connected with the cooling interior utmost point, the other end of described K switch 4 is connected with the cooling outer utmost point, one end of described K switch 1 is connected with one end of K switch 2, the cathode output end of described bridge rectifier is connected with the connected node of K switch 2 with K switch 1, the other end ground connection of described K switch 1, the other end of described K switch 2 is connected with the molten steel utmost point.
2. crucible electric induction furnace runout warning circuit according to claim 1, is characterized in that, between described change-over switch K and relay K M normal open switch KM-1, is in series with fusible link FU1, between described transformer T and bridge rectifier, is in series with fusible link FU2.
3. crucible electric induction furnace runout warning circuit according to claim 1, it is characterized in that, between described bridge rectifier cathode output end and K switch 1 and the connected node of K switch 2, be in series with a Zener diode D and sampling resistor R3, described rectification circuit cathode output end is connected with the P utmost point of Zener diode D, the N utmost point of described Zener diode D is connected with one end of sampling resistor R3, and the other end of described sampling resistor R3 is connected with the connected node of K switch 2 with K switch 1.
4. according to the crucible electric induction furnace runout warning circuit described in claim 2 or 3, it is characterized in that, the cooling outer utmost point of described cooler bin is also connected with resistance R 4, resistance R 5, resistance R 6 and resistance R 7, one end of described resistance R 4, resistance R 5, resistance R 6 and resistance R 7 is connected with the cooling outer utmost point, other end ground connection.
5. crucible electric induction furnace runout warning circuit according to claim 4, is characterized in that, described resistance R 4, resistance R 5, resistance R 6 and resistance R 7 are earth resistance, and resistance is identical.
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| CN201410311785.4A CN104034157A (en) | 2014-07-02 | 2014-07-02 | Runout alarm circuit of crucible electric induction furnace |
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| CN201410311785.4A CN104034157A (en) | 2014-07-02 | 2014-07-02 | Runout alarm circuit of crucible electric induction furnace |
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| CN110514894A (en) * | 2019-07-24 | 2019-11-29 | 中石化南京工程有限公司 | A kind of electric furnace short net cooling water system design method based on electric leakage safety |
| CN112449454A (en) * | 2019-09-02 | 2021-03-05 | 富士电机株式会社 | Induction furnace and method for operating induction furnace |
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Application publication date: 20140910 |