| 摘要 |
<p>PURPOSE:To ensure efficient and uniform melting in an initial melting process with simple constitution by providing a breaker for changing over and connecting the secondary output of a transformer to a rectifier and the movable electrode of a DC arc furnace for use as an AC arc furnace, as well. CONSTITUTION:There are provided breakers 8a and 8c for changing over and connecting the secondary output of transformers 3a to 3c to rectifiers 2b, 2d and 2f, and a movable electrode of a DC arc furnace 1. Furthermore, the secondary output of the transformers 3a to 3c is changed over for connection to the movable electrode of the DC furnace 1 in an initial melting process via the operation of the breakers 8a to 8c, thereby supplying an AC power supply to the movable electrode of the DC arc furnace 1 and using the furnace as an ordinary AC arc furnace via the employment of the position control of the movable electrode. According to the aforesaid construction, the DC arc furnace can be used as a three-phase AC furnace at an initial melting process. In addition, each electrode can be supplied with uniform currents independent of the poor conductivity of a furnace bottom electrode, an efficient and uniform melting process can be ensured.</p> |
