| 摘要 |
<p>PURPOSE:To ensure uniform melting of a scrap with a simplified structure in a direct arc furnace for melting the scrap by providing a control circuit for individually controlling an anode and a cathode which are made movable in their upper portions. CONSTITUTION:A direct arc furnace 9 is supplied with DC power from a DC power supply device 1, and arcing is produced between an upper movable electrode 2A of an anode and an upper movable electrode 2B of a cathode to melt a scrap 10. The upper movable electrodes 2A, 2B are individually elevated with the control circuit in an electrode elevation control device 6, and DC output voltage between both electrodes detected by a DC voltage detector 5 is set to a set value supplied from a voltage setting unit 4, and further arc voltage between the anode and the scrap and arc voltage between the cathode and the scrap is controlled to a regulated set value evaluated by multipliers 11A, 11B. Hereby, the needs of an exchange work of a furnace bottom electrode and of a device for the furnace bottom electrode.</p> |
