To avoid wasteful power consumption and the like by surely determining completion of dissolution of scrap.
A dissolution state determination device of an arc furnace includes a noise meter 71 detecting noise generated in the arc furnace and outputting a sound signal 71a corresponding to intensity of detected sound, a frequency analyzing device 72 analyzing a frequency of the sound signal 71a and obtaining a frequency-intensity signal 72a, and a control device 4 determining the completion of dissolution when a state that at least a part of signal component of the frequency-intensity signal 72a is included in a first detection region, in the first detection region set in a region centered on a frequency of an even multiple of basic frequency, within a prescribed signal intensity range, and all of signal components of the frequency-intensity signal 72a are included in second and third detection regions in the second and third detection regions respectively set in prescribed signal intensity ranges in frequency regions at a low frequency side and high frequency side with respect to the frequency of the even multiple, is kept for a prescribed time or more.
OHASHI TAKAHIRO
SATO MITSUHIKO
KITABAYASHI SHOJI
KAMESHIMA TAKATOSHI
TAKAMIYA HITOSHIGE
SASAKI SHOJI
GODO SEITETSU
| JPH1183330A | 1999-03-26 | |||
| JPH02101381A | 1990-04-13 | |||
| JPS59205189A | 1984-11-20 | |||
| JPH1183330A | 1999-03-26 | |||
| JPH02101381A | 1990-04-13 | |||
| JPS59205189A | 1984-11-20 |
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