| 摘要 |
Provided are a facility and a method for manufacturing a continuous hot-dip zinc-coated steel sheet, whereby it becomes possible to ensure the maintenance of quality and a plating property of a plated product at high levels and in a steady manner. A facility for manufacturing a continuous hot-dip zinc-coated steel sheet, in which a continuous annealing furnace, which is a furnace partitioned into three zones in total, i.e., a heating zone for heating a steel strip that is a strip-shaped steel sheet to be passed through the furnace, a burning zone for burning the steel strip and a cooling zone for cooling the steel strip arranged in this order as observed from the upstream side of a passage through which the steel strip passes, is directly connected to a hot-melt zinc plating bath through a snout which is a closed space passage for directly sending the steel strip from the furnace into the plating bath. The facility is characterized by being provided with: a dew point meter and a suction outlet port and a blowing port both for a gas in the furnace, all of which are provided in any one of the three zones; gas circulation passages to a refiner that is a water removal apparatus provided outside the furnace, wherein the gas circulation passages are formed separately in the zones in each of which the refiner is connected to the suction outlet port and the blowing port; and a dew point meter and a humidifier for humidifying the inside of the snout, both of which are provided in the snout. The facility is also characterized in that the refiner can operate in such a manner that the measurement value by the dew point meter in each of the connected zones coincides with an intended dew point in each of the gas circulation passages, and the humidifier can operate in such a manner that the measurement value by the dew point meter in the snout coincides with an intended dew point for the snout. |
