METHOD AND DEVICE FOR AUTOMATICALLY DETECTING THE INTACTNESS OF GROUND ELECTRODES IN THE BATH OF AN INDUCTION FURNACE AND INDUCTION FURNACE

摘要

A method and an apparatus for automatically detecting the intactness of ground electrodes in the bath of an induction furnace are described. According to the method a low DC or AC current is applied to an additional insulated electrode extending through the furnace bottom and being in connection with the melt. After melting of the charge this current is measured and compared with a reference value. If the magnitude of the current drops below the reference value an alarm signal is generated. Furthermore, methods and devices for localizing a ground fault are described. By this, the security of the operation of an induction furnace is improved.

主权项

1. A method for automatically detecting the intactness of ground electrodes in the bath of an induction furnace that has an induction furnace jacket with a refractory lining and an induction coil surrounding the same as well as a ground-fault detector with at least one bath ground electrode in the lower part of the refractory lining that extends through the furnace bottom and is in connection with the bath melt, the method comprising the following steps:
a low DC or AC current is supplied to an additional insulated electrode extending through the furnace bottom and being in connection with the melt, the current flowing from this electrode through the melt bath to the at least one bath ground electrode to ground, after melting of the charge this current is measured and is compared with a reference value, and an alarm signal indicating a defect of the bath ground electrode is generated when the magnitude of the current drops below the reference value.