冶炼磁性能差的钢种应注意的问题

1、冶炼一些导磁性能差或非磁性材料时，由于磁导率降低，使主磁通 减少，降低了热效率。

2、主磁通与漏磁通是同时存在的，往往漏磁通要比主磁通大，当冶炼导 磁性能差或非磁性材料钢种时，由于漏磁磁通的增大，表现出来的现象是直流电流大而中频感应电压(直流电压)低。

3、晶闸管的可靠换流是靠反向电压使晶闸管可靠关断实现的，如中频炉电 压和直流电压低，会使晶闸管换流困难，甚至会出现不关断直通短路现象，严重威胁中频炉及中频电源内部的晶闸管的安全运行。

4、导磁性能差的钢种有RH13、20Mn23AlV、45Mnl7A13_o冶炼上述导磁性能较差的钢种时，一定要忽略功率，密切注意电流的变化，一要使直流电流在KP管额定电流60%以下运行，二要注意直流电压，尽量使其高电压运行，以便使中频电源内部的晶闸管KK、KP管可靠换流。

Points for Attention in Smelting Steels with Poor Magnetic Properties

1. When smelting some materials with poor magnetic permeability or non-magnetic properties, the main magnetic flux is reduced due to the decrease of magnetic permeability, which reduces the thermal efficiency.

2. The main magnetic flux and the leakage magnetic flux exist at the same time, and the leakage magnetic flux is often larger than the main magnetic flux. When smelting the steel with poor magnetic permeability or non-magnetic material, the leakage magnetic flux increases. The phenomenon is that the DC current is large and the intermediate frequency induced voltage (DC voltage) is low.

3. Reliable commutation of the thyristor is achieved by the reverse voltage to make the thyristor reliably shut down. If the voltage of the induction melting furnace and the DC voltage are low, it will make the thyristor commutation difficult, and even the phenomenon of non-turn-off through short circuit will seriously threaten induction melting. Safe operation of the thyristor inside the furnace and the intermediate frequency power supply.

4. Steel grades with poor magnetic permeability include RH13, 20Mn23AlV, 45Mnl7A13o. When smelting the above-mentioned steel grades with poor magnetic permeability, you must ignore the power and pay close attention to the current changes. First, make the DC current 60% of the rated current of the KP tube. For the following operations, two should pay attention to the DC voltage, and try to make it run at a high voltage, so that the thyristor KK and KP inside the intermediate frequency power supply can be reliably commutated.