To provide an operating method for the steel strip continuously processing line by which a line operation can be performed by maintaining the upstream side in the threading conditions, without being affected by the processing operation in the downstream side of the line, in the steel strip processing line (the delivery line of the continuously annealing furnace).
A looper 6 for storing the steel strip is provided between the upstream side processing portion (skin pass mill 2) and the downstream side processing portion (a side trimmer 6, an inspection room 9) and the looper 6 absorbs the difference of the line speeds between the upstream side and the downstream side. Even if the threading of the steel strip is suspended temporarily in the side trimmer 6 and the inspection room 9 in the downstream side, the operation of the skin pass mill 2 in the upstream side can be maintained. The steel strap storage in the looper 4 can be diminished by duly increasing the downstream side speed after reopening the threading of the downstream processing portion. Defects such as a stop mark (a rolling trace of the skin pass mill) and an accompanying yield loss can be dissolved without suspending the skin pass mill.
TAKAHARA KATSUAKI
NAKAGIRI SHINICHI
