Teach you how to operate the induction melting furnace

Start-up standard of induction melting furnace:

Before starting up, check whether the electrical circuit is good, whether the components are damaged, whether each contact point is loose or disconnected

Phenomenon, if the above situation occurs, the power supply can be turned on after the fault is eliminated.

(1) Call the substation staff on duty to close the switch cabinet of the induction melting furnace, power the induction melting furnace, and sign the power transmission record;

(2) Wear gloves and close the six manual switches under the power distribution cabinet, and observe whether the incoming voltmeter on the panel matches the supply voltage, and the three-phase incoming voltage is required to be balanced;

(3) Start the incoming line voltmeter on the power supply cabinet to display the power supply voltage, the power-on indicator light (yellow) is on, and the inverter power signal light (red) is on, first turn the power potentiometer counterclockwise to the zero position (to the end), and press the inverter The work button (green), the inverter work indicator light (green) is on, and the pointer of the DC voltmeter on the door panel should be below zero scale;

(4) Liter power. First, adjust the power potentiometer clockwise slightly. At this time, pay attention to the establishment of the intermediate frequency and hear the whistling sound, indicating that the intermediate frequency power supply has been started successfully. Only then can the power potentiometer be allowed to rotate slowly in the clockwise direction, and not pull it up quickly. Power, increase the power slowly, if the IF frequency is still not established, turn the potentiometer back and restart;

(5) When the power is turned on, if there is no or abnormal sound at the intermediate frequency frequency, it should not be forced to start, then the potentiometer should be retracted counterclockwise to the end, and then restarted. If several times are unsuccessful, it should be shut down and checked;

(6) At the initial stage of loading (when continuously loading steel ingots), the power should be adjusted to 2000kW, so that the power adjustment potentiometer should have a margin (the potentiometer must not be adjusted to full) to prevent sudden increase in power and current due to the loading process High, causing damage to the thyristor. After the loading is completed, slowly increase the power to more than 3000kW;

(7) In the middle and late stages of smelting, the power should be reduced to 2000kW (reduced power). After the filling is completed, slowly adjust the power to more than 3000kW to prevent the sudden increase in power and current during the charging process. Impact damage of the thyristor;

(8) If there is material buildup in the furnace, do not fully adjust the power potentiometer at this time, and do not operate at high power. The power should be controlled at 2000kW to prevent the steel ingots from falling into the furnace suddenly, causing a sudden increase in power and current. , Causing impact damage to the thyristor;

(9) During the smelting process, if the system suddenly trips, you should carefully identify the cause of the trip, and carefully check the power cabinet and the intermediate frequency power system for leaks, normal pressure, and signs of ignition. Do not restart the intermediate frequency power supply blindly. , To prevent the expansion of the fault, causing damage to the power system, thyristor and main board;

(10) The normal relationship between current and voltage when the power is adjusted to the full power potentiometer is:

IF voltage = DC voltage x 1.3

DC voltage = incoming line voltage x 1.3

DC current = incoming line current x 1.2

(11) After confirming that everything is normal after closing, hang the (power transmission) sign on the manual brake.

Induction melting furnace shutdown standard

(1) First turn the power potentiometer counterclockwise to the end. When the DC ammeter, DC voltmeter, frequency meter, intermediate frequency voltmeter, and power meter on the inverter power cabinet are all zero, press the inverter stop button (red), The inverter stop indicator light (red) is on.

(2) Pull down the six manual switches at the lower part of the power distribution cabinet, and hang up the (power failure) sign.

(3) Notify the substation on-duty personnel to disconnect the switchgear and cut off the power to the induction melting furnace.

(4) During the operation of the inverter power supply, the electrical instruments should be recorded and monitored as required. If abnormal conditions are found, the machine should be shut down and the cause should be checked immediately, and the operation can be continued after the fault is eliminated.

(5) During the operation of the inverter power supply, if water leakage or blockage is found in the waterway and water-cooling components, the machine should be shut down and checked and dealt with. After repairing and drying with a hair dryer, it can be turned on and used again.

(6) During the operation of the inverter power supply, it is strictly forbidden to conduct tilting observation, tilting tapping, and feeding operations with power on. The above operations must be performed after stopping the inverter power supply.